/* GStreamer
 *
 * Copyright (C) 2001-2002 Ronald Bultje <rbultje@ronald.bitfreak.net>
 *               2006 Edgard Lima <edgard.lima@gmail.com>
 *
 * gstv4l2object.c: base class for V4L2 elements
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as published
 * by the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version. This library is distributed in the hope
 * that it will be useful, but WITHOUT ANY WARRANTY; without even the
 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 * PURPOSE.  See the GNU Library General Public License for more details.
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301,
 * USA.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <sys/file.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/ioctl.h>


#ifdef HAVE_GUDEV
#include <gudev/gudev.h>
#endif

#include "ext/videodev2.h"
#include "gstv4l2object.h"
#include "gstv4l2tuner.h"
#include "gstv4l2colorbalance.h"

#include "gst/gst-i18n-plugin.h"

#include <gst/video/video.h>
#include <gst/allocators/gstdmabuf.h>

GST_DEBUG_CATEGORY_EXTERN (v4l2_debug);
#define GST_CAT_DEFAULT v4l2_debug

#define DEFAULT_PROP_DEVICE_NAME        NULL
#define DEFAULT_PROP_DEVICE_FD          -1
#define DEFAULT_PROP_FLAGS              0
#define DEFAULT_PROP_TV_NORM            0
#define DEFAULT_PROP_IO_MODE            GST_V4L2_IO_AUTO

#define ENCODED_BUFFER_SIZE             (2 * 1024 * 1024)

enum
{
  PROP_0,
  V4L2_STD_OBJECT_PROPS,
};

/*
 * common format / caps utilities:
 */
typedef enum
{
  GST_V4L2_RAW = 1 << 0,
  GST_V4L2_CODEC = 1 << 1,
  GST_V4L2_TRANSPORT = 1 << 2,
  GST_V4L2_NO_PARSE = 1 << 3,
  GST_V4L2_ALL = 0xffff
} GstV4L2FormatFlags;

typedef struct
{
  guint32 format;
  gboolean dimensions;
  GstV4L2FormatFlags flags;
} GstV4L2FormatDesc;

static const GstV4L2FormatDesc gst_v4l2_formats[] = {
  /* RGB formats */
  {V4L2_PIX_FMT_RGB332, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_ARGB555, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_XRGB555, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_ARGB555X, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_XRGB555X, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_RGB565, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_RGB565X, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_BGR666, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_BGR24, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_RGB24, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_ABGR32, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_XBGR32, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_ARGB32, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_XRGB32, TRUE, GST_V4L2_RAW},

  /* Deprecated Packed RGB Image Formats (alpha ambiguity) */
  {V4L2_PIX_FMT_RGB444, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_RGB555, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_RGB555X, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_BGR32, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_RGB32, TRUE, GST_V4L2_RAW},

  /* Grey formats */
  {V4L2_PIX_FMT_GREY, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_Y4, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_Y6, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_Y10, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_Y12, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_Y16, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_Y16_BE, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_Y10BPACK, TRUE, GST_V4L2_RAW},

  /* Palette formats */
  {V4L2_PIX_FMT_PAL8, TRUE, GST_V4L2_RAW},

  /* Chrominance formats */
  {V4L2_PIX_FMT_UV8, TRUE, GST_V4L2_RAW},

  /* Luminance+Chrominance formats */
  {V4L2_PIX_FMT_YVU410, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YVU420, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YVU420M, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YUYV, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YYUV, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YVYU, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_UYVY, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_VYUY, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YUV422P, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YUV411P, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_Y41P, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YUV444, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YUV555, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YUV565, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YUV32, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YUV410, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YUV420, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_YUV420M, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_HI240, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_HM12, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_M420, TRUE, GST_V4L2_RAW},

  /* two planes -- one Y, one Cr + Cb interleaved  */
  {V4L2_PIX_FMT_NV12, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV12M, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV12MT, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV12MT_16X16, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV21, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV21M, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV16, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV16M, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV61, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV61M, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV24, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_NV42, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_XV15, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_XV20, TRUE, GST_V4L2_RAW},

  /* Bayer formats - see http://www.siliconimaging.com/RGB%20Bayer.htm */
  {V4L2_PIX_FMT_SBGGR8, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_SGBRG8, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_SGRBG8, TRUE, GST_V4L2_RAW},
  {V4L2_PIX_FMT_SRGGB8, TRUE, GST_V4L2_RAW},

  /* compressed formats */
  {V4L2_PIX_FMT_MJPEG, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_JPEG, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_PJPG, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_DV, FALSE, GST_V4L2_TRANSPORT},
  {V4L2_PIX_FMT_MPEG, FALSE, GST_V4L2_TRANSPORT},
  {V4L2_PIX_FMT_FWHT, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_H264, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_H264_NO_SC, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_H264_MVC, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_HEVC, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_H263, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_MPEG1, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_MPEG2, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_MPEG4, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_XVID, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_VC1_ANNEX_G, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_VC1_ANNEX_L, FALSE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_VP8, FALSE, GST_V4L2_CODEC | GST_V4L2_NO_PARSE},
  {V4L2_PIX_FMT_VP9, FALSE, GST_V4L2_CODEC | GST_V4L2_NO_PARSE},

  /*  Vendor-specific formats   */
  {V4L2_PIX_FMT_WNVA, TRUE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_SN9C10X, TRUE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_PWC1, TRUE, GST_V4L2_CODEC},
  {V4L2_PIX_FMT_PWC2, TRUE, GST_V4L2_CODEC},
};

#define GST_V4L2_FORMAT_COUNT (G_N_ELEMENTS (gst_v4l2_formats))

static GSList *gst_v4l2_object_get_format_list (GstV4l2Object * v4l2object);


#define GST_TYPE_V4L2_DEVICE_FLAGS (gst_v4l2_device_get_type ())
static GType
gst_v4l2_device_get_type (void)
{
  static GType v4l2_device_type = 0;

  if (v4l2_device_type == 0) {
    static const GFlagsValue values[] = {
      {V4L2_CAP_VIDEO_CAPTURE, "Device supports video capture", "capture"},
      {V4L2_CAP_VIDEO_OUTPUT, "Device supports video playback", "output"},
      {V4L2_CAP_VIDEO_OVERLAY, "Device supports video overlay", "overlay"},

      {V4L2_CAP_VBI_CAPTURE, "Device supports the VBI capture", "vbi-capture"},
      {V4L2_CAP_VBI_OUTPUT, "Device supports the VBI output", "vbi-output"},

      {V4L2_CAP_TUNER, "Device has a tuner or modulator", "tuner"},
      {V4L2_CAP_AUDIO, "Device has audio inputs or outputs", "audio"},

      {0, NULL, NULL}
    };

    v4l2_device_type =
        g_flags_register_static ("GstV4l2DeviceTypeFlags", values);
  }

  return v4l2_device_type;
}

#define GST_TYPE_V4L2_TV_NORM (gst_v4l2_tv_norm_get_type ())
static GType
gst_v4l2_tv_norm_get_type (void)
{
  static GType v4l2_tv_norm = 0;

  if (!v4l2_tv_norm) {
    static const GEnumValue tv_norms[] = {
      {0, "none", "none"},

      {V4L2_STD_NTSC, "NTSC", "NTSC"},
      {V4L2_STD_NTSC_M, "NTSC-M", "NTSC-M"},
      {V4L2_STD_NTSC_M_JP, "NTSC-M-JP", "NTSC-M-JP"},
      {V4L2_STD_NTSC_M_KR, "NTSC-M-KR", "NTSC-M-KR"},
      {V4L2_STD_NTSC_443, "NTSC-443", "NTSC-443"},

      {V4L2_STD_PAL, "PAL", "PAL"},
      {V4L2_STD_PAL_BG, "PAL-BG", "PAL-BG"},
      {V4L2_STD_PAL_B, "PAL-B", "PAL-B"},
      {V4L2_STD_PAL_B1, "PAL-B1", "PAL-B1"},
      {V4L2_STD_PAL_G, "PAL-G", "PAL-G"},
      {V4L2_STD_PAL_H, "PAL-H", "PAL-H"},
      {V4L2_STD_PAL_I, "PAL-I", "PAL-I"},
      {V4L2_STD_PAL_DK, "PAL-DK", "PAL-DK"},
      {V4L2_STD_PAL_D, "PAL-D", "PAL-D"},
      {V4L2_STD_PAL_D1, "PAL-D1", "PAL-D1"},
      {V4L2_STD_PAL_K, "PAL-K", "PAL-K"},
      {V4L2_STD_PAL_M, "PAL-M", "PAL-M"},
      {V4L2_STD_PAL_N, "PAL-N", "PAL-N"},
      {V4L2_STD_PAL_Nc, "PAL-Nc", "PAL-Nc"},
      {V4L2_STD_PAL_60, "PAL-60", "PAL-60"},

      {V4L2_STD_SECAM, "SECAM", "SECAM"},
      {V4L2_STD_SECAM_B, "SECAM-B", "SECAM-B"},
      {V4L2_STD_SECAM_G, "SECAM-G", "SECAM-G"},
      {V4L2_STD_SECAM_H, "SECAM-H", "SECAM-H"},
      {V4L2_STD_SECAM_DK, "SECAM-DK", "SECAM-DK"},
      {V4L2_STD_SECAM_D, "SECAM-D", "SECAM-D"},
      {V4L2_STD_SECAM_K, "SECAM-K", "SECAM-K"},
      {V4L2_STD_SECAM_K1, "SECAM-K1", "SECAM-K1"},
      {V4L2_STD_SECAM_L, "SECAM-L", "SECAM-L"},
      {V4L2_STD_SECAM_LC, "SECAM-Lc", "SECAM-Lc"},

      {0, NULL, NULL}
    };

    v4l2_tv_norm = g_enum_register_static ("V4L2_TV_norms", tv_norms);
  }

  return v4l2_tv_norm;
}

GType
gst_v4l2_io_mode_get_type (void)
{
  static GType v4l2_io_mode = 0;

  if (!v4l2_io_mode) {
    static const GEnumValue io_modes[] = {
      {GST_V4L2_IO_AUTO, "GST_V4L2_IO_AUTO", "auto"},
      {GST_V4L2_IO_RW, "GST_V4L2_IO_RW", "rw"},
      {GST_V4L2_IO_MMAP, "GST_V4L2_IO_MMAP", "mmap"},
      {GST_V4L2_IO_USERPTR, "GST_V4L2_IO_USERPTR", "userptr"},
      {GST_V4L2_IO_DMABUF, "GST_V4L2_IO_DMABUF", "dmabuf"},
      {GST_V4L2_IO_DMABUF_IMPORT, "GST_V4L2_IO_DMABUF_IMPORT",
          "dmabuf-import"},

      {0, NULL, NULL}
    };
    v4l2_io_mode = g_enum_register_static ("GstV4l2IOMode", io_modes);
  }
  return v4l2_io_mode;
}

void
gst_v4l2_object_install_properties_helper (GObjectClass * gobject_class,
    const char *default_device)
{
  g_object_class_install_property (gobject_class, PROP_DEVICE,
      g_param_spec_string ("device", "Device", "Device location",
          default_device, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
  g_object_class_install_property (gobject_class, PROP_DEVICE_NAME,
      g_param_spec_string ("device-name", "Device name",
          "Name of the device", DEFAULT_PROP_DEVICE_NAME,
          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
  g_object_class_install_property (gobject_class, PROP_DEVICE_FD,
      g_param_spec_int ("device-fd", "File descriptor",
          "File descriptor of the device", -1, G_MAXINT, DEFAULT_PROP_DEVICE_FD,
          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
  g_object_class_install_property (gobject_class, PROP_FLAGS,
      g_param_spec_flags ("flags", "Flags", "Device type flags",
          GST_TYPE_V4L2_DEVICE_FLAGS, DEFAULT_PROP_FLAGS,
          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  /**
   * GstV4l2Src:brightness:
   *
   * Picture brightness, or more precisely, the black level
   */
  g_object_class_install_property (gobject_class, PROP_BRIGHTNESS,
      g_param_spec_int ("brightness", "Brightness",
          "Picture brightness, or more precisely, the black level", G_MININT,
          G_MAXINT, 0,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | GST_PARAM_CONTROLLABLE));
  /**
   * GstV4l2Src:contrast:
   *
   * Picture contrast or luma gain
   */
  g_object_class_install_property (gobject_class, PROP_CONTRAST,
      g_param_spec_int ("contrast", "Contrast",
          "Picture contrast or luma gain", G_MININT,
          G_MAXINT, 0,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | GST_PARAM_CONTROLLABLE));
  /**
   * GstV4l2Src:saturation:
   *
   * Picture color saturation or chroma gain
   */
  g_object_class_install_property (gobject_class, PROP_SATURATION,
      g_param_spec_int ("saturation", "Saturation",
          "Picture color saturation or chroma gain", G_MININT,
          G_MAXINT, 0,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | GST_PARAM_CONTROLLABLE));
  /**
   * GstV4l2Src:hue:
   *
   * Hue or color balance
   */
  g_object_class_install_property (gobject_class, PROP_HUE,
      g_param_spec_int ("hue", "Hue",
          "Hue or color balance", G_MININT,
          G_MAXINT, 0,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | GST_PARAM_CONTROLLABLE));

  /**
   * GstV4l2Src:norm:
   *
   * TV norm
   */
  g_object_class_install_property (gobject_class, PROP_TV_NORM,
      g_param_spec_enum ("norm", "TV norm",
          "video standard",
          GST_TYPE_V4L2_TV_NORM, DEFAULT_PROP_TV_NORM,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  /**
   * GstV4l2Src:io-mode:
   *
   * IO Mode
   */
  g_object_class_install_property (gobject_class, PROP_IO_MODE,
      g_param_spec_enum ("io-mode", "IO mode",
          "I/O mode",
          GST_TYPE_V4L2_IO_MODE, DEFAULT_PROP_IO_MODE,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  /**
   * GstV4l2Src:extra-controls:
   *
   * Additional v4l2 controls for the device. The controls are identified
   * by the control name (lowercase with '_' for any non-alphanumeric
   * characters).
   *
   * Since: 1.2
   */
  g_object_class_install_property (gobject_class, PROP_EXTRA_CONTROLS,
      g_param_spec_boxed ("extra-controls", "Extra Controls",
          "Extra v4l2 controls (CIDs) for the device",
          GST_TYPE_STRUCTURE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  /**
   * GstV4l2Src:pixel-aspect-ratio:
   *
   * The pixel aspect ratio of the device. This overwrites the pixel aspect
   * ratio queried from the device.
   *
   * Since: 1.2
   */
  g_object_class_install_property (gobject_class, PROP_PIXEL_ASPECT_RATIO,
      g_param_spec_string ("pixel-aspect-ratio", "Pixel Aspect Ratio",
          "Overwrite the pixel aspect ratio of the device", "1/1",
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  /**
   * GstV4l2Src:force-aspect-ratio:
   *
   * When enabled, the pixel aspect ratio queried from the device or set
   * with the pixel-aspect-ratio property will be enforced.
   *
   * Since: 1.2
   */
  g_object_class_install_property (gobject_class, PROP_FORCE_ASPECT_RATIO,
      g_param_spec_boolean ("force-aspect-ratio", "Force aspect ratio",
          "When enabled, the pixel aspect ratio will be enforced", TRUE,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  /**
   * GstV4l2Src:force-ntsc-tv:
   *
   * When enabled, capture NTSC DV (720x480i) content from
   * NTSC TV D1 (720x486i) source.
   */
  g_object_class_install_property (gobject_class, PROP_FORCE_NTSC_TV,
      g_param_spec_boolean ("force-ntsc-tv", "Capture NTSC DV from NTSC TV D1",
          "When enabled, capture NTSC DV (720x480i) content from NTSC TV D1 (720x486i) source.",
          FALSE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
}

void
gst_v4l2_object_install_m2m_properties_helper (GObjectClass * gobject_class)
{
  g_object_class_install_property (gobject_class, PROP_DEVICE,
      g_param_spec_string ("device", "Device", "Device location",
          NULL, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_DEVICE_NAME,
      g_param_spec_string ("device-name", "Device name",
          "Name of the device", DEFAULT_PROP_DEVICE_NAME,
          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_DEVICE_FD,
      g_param_spec_int ("device-fd", "File descriptor",
          "File descriptor of the device", -1, G_MAXINT, DEFAULT_PROP_DEVICE_FD,
          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_OUTPUT_IO_MODE,
      g_param_spec_enum ("output-io-mode", "Output IO mode",
          "Output side I/O mode (matches sink pad)",
          GST_TYPE_V4L2_IO_MODE, DEFAULT_PROP_IO_MODE,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_CAPTURE_IO_MODE,
      g_param_spec_enum ("capture-io-mode", "Capture IO mode",
          "Capture I/O mode (matches src pad)",
          GST_TYPE_V4L2_IO_MODE, DEFAULT_PROP_IO_MODE,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_EXTRA_CONTROLS,
      g_param_spec_boxed ("extra-controls", "Extra Controls",
          "Extra v4l2 controls (CIDs) for the device",
          GST_TYPE_STRUCTURE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
}

/* Support for 32bit off_t, this wrapper is casting off_t to gint64 */
#ifdef HAVE_LIBV4L2
#if SIZEOF_OFF_T < 8

static gpointer
v4l2_mmap_wrapper (gpointer start, gsize length, gint prot, gint flags, gint fd,
    off_t offset)
{
  return v4l2_mmap (start, length, prot, flags, fd, (gint64) offset);
}

#define v4l2_mmap v4l2_mmap_wrapper

#endif /* SIZEOF_OFF_T < 8 */
#endif /* HAVE_LIBV4L2 */

GstV4l2Object *
gst_v4l2_object_new (GstElement * element,
    GstObject * debug_object,
    enum v4l2_buf_type type,
    const char *default_device,
    GstV4l2GetInOutFunction get_in_out_func,
    GstV4l2SetInOutFunction set_in_out_func,
    GstV4l2UpdateFpsFunction update_fps_func)
{
  GstV4l2Object *v4l2object;

  /*
   * some default values
   */
  v4l2object = g_new0 (GstV4l2Object, 1);

  v4l2object->type = type;
  v4l2object->formats = NULL;

  v4l2object->element = element;
  v4l2object->dbg_obj = debug_object;
  v4l2object->get_in_out_func = get_in_out_func;
  v4l2object->set_in_out_func = set_in_out_func;
  v4l2object->update_fps_func = update_fps_func;

  v4l2object->video_fd = -1;
  v4l2object->active = FALSE;
  v4l2object->videodev = g_strdup (default_device);

  v4l2object->norms = NULL;
  v4l2object->channels = NULL;
  v4l2object->colors = NULL;

  v4l2object->keep_aspect = TRUE;
  v4l2object->force_ntsc_tv = FALSE;

  v4l2object->n_v4l2_planes = 0;
  v4l2object->no_initial_format = FALSE;
  v4l2object->sync_chan.enabled = FALSE;
  v4l2object->xlnx_ll = FALSE;
  v4l2object->xlnx_ll_dma_started = FALSE;

  /* We now disable libv4l2 by default, but have an env to enable it. */
#ifdef HAVE_LIBV4L2
  if (g_getenv ("GST_V4L2_USE_LIBV4L2")) {
    v4l2object->fd_open = v4l2_fd_open;
    v4l2object->close = v4l2_close;
    v4l2object->dup = v4l2_dup;
    v4l2object->ioctl = v4l2_ioctl;
    v4l2object->read = v4l2_read;
    v4l2object->mmap = v4l2_mmap;
    v4l2object->munmap = v4l2_munmap;
  } else
#endif
  {
    v4l2object->fd_open = NULL;
    v4l2object->close = close;
    v4l2object->dup = dup;
    v4l2object->ioctl = ioctl;
    v4l2object->read = read;
    v4l2object->mmap = mmap;
    v4l2object->munmap = munmap;
  }

  return v4l2object;
}

static gboolean gst_v4l2_object_clear_format_list (GstV4l2Object * v4l2object);


void
gst_v4l2_object_destroy (GstV4l2Object * v4l2object)
{
  g_return_if_fail (v4l2object != NULL);

  g_free (v4l2object->videodev);

  g_free (v4l2object->channel);

  if (v4l2object->formats) {
    gst_v4l2_object_clear_format_list (v4l2object);
  }

  if (v4l2object->probed_caps) {
    gst_caps_unref (v4l2object->probed_caps);
  }

  if (v4l2object->extra_controls) {
    gst_structure_free (v4l2object->extra_controls);
  }

  g_free (v4l2object);
}


static gboolean
gst_v4l2_object_clear_format_list (GstV4l2Object * v4l2object)
{
  g_slist_foreach (v4l2object->formats, (GFunc) g_free, NULL);
  g_slist_free (v4l2object->formats);
  v4l2object->formats = NULL;

  return TRUE;
}

static gint
gst_v4l2_object_prop_to_cid (guint prop_id)
{
  gint cid = -1;

  switch (prop_id) {
    case PROP_BRIGHTNESS:
      cid = V4L2_CID_BRIGHTNESS;
      break;
    case PROP_CONTRAST:
      cid = V4L2_CID_CONTRAST;
      break;
    case PROP_SATURATION:
      cid = V4L2_CID_SATURATION;
      break;
    case PROP_HUE:
      cid = V4L2_CID_HUE;
      break;
    default:
      GST_WARNING ("unmapped property id: %d", prop_id);
  }
  return cid;
}


gboolean
gst_v4l2_object_set_property_helper (GstV4l2Object * v4l2object,
    guint prop_id, const GValue * value, GParamSpec * pspec)
{
  switch (prop_id) {
    case PROP_DEVICE:
      gst_v4l2_object_set_device (v4l2object, g_value_get_string (value));
      break;
    case PROP_BRIGHTNESS:
    case PROP_CONTRAST:
    case PROP_SATURATION:
    case PROP_HUE:
    {
      gint cid = gst_v4l2_object_prop_to_cid (prop_id);

      if (cid != -1) {
        if (GST_V4L2_IS_OPEN (v4l2object)) {
          gst_v4l2_set_attribute (v4l2object, cid, g_value_get_int (value));
        }
      }
      return TRUE;
    }
      break;
    case PROP_TV_NORM:
      v4l2object->tv_norm = g_value_get_enum (value);
      break;
#if 0
    case PROP_CHANNEL:
      if (GST_V4L2_IS_OPEN (v4l2object)) {
        GstTuner *tuner = GST_TUNER (v4l2object->element);
        GstTunerChannel *channel = gst_tuner_find_channel_by_name (tuner,
            (gchar *) g_value_get_string (value));

        if (channel) {
          /* like gst_tuner_set_channel (tuner, channel)
             without g_object_notify */
          gst_v4l2_tuner_set_channel (v4l2object, channel);
        }
      } else {
        g_free (v4l2object->channel);
        v4l2object->channel = g_value_dup_string (value);
      }
      break;
    case PROP_FREQUENCY:
      if (GST_V4L2_IS_OPEN (v4l2object)) {
        GstTuner *tuner = GST_TUNER (v4l2object->element);
        GstTunerChannel *channel = gst_tuner_get_channel (tuner);

        if (channel &&
            GST_TUNER_CHANNEL_HAS_FLAG (channel, GST_TUNER_CHANNEL_FREQUENCY)) {
          /* like
             gst_tuner_set_frequency (tuner, channel, g_value_get_ulong (value))
             without g_object_notify */
          gst_v4l2_tuner_set_frequency (v4l2object, channel,
              g_value_get_ulong (value));
        }
      } else {
        v4l2object->frequency = g_value_get_ulong (value);
      }
      break;
#endif

    case PROP_IO_MODE:
      v4l2object->req_mode = g_value_get_enum (value);
      break;
    case PROP_CAPTURE_IO_MODE:
      g_return_val_if_fail (!V4L2_TYPE_IS_OUTPUT (v4l2object->type), FALSE);
      v4l2object->req_mode = g_value_get_enum (value);
      break;
    case PROP_OUTPUT_IO_MODE:
      g_return_val_if_fail (V4L2_TYPE_IS_OUTPUT (v4l2object->type), FALSE);
      v4l2object->req_mode = g_value_get_enum (value);
      break;
    case PROP_EXTRA_CONTROLS:{
      const GstStructure *s = gst_value_get_structure (value);

      if (v4l2object->extra_controls)
        gst_structure_free (v4l2object->extra_controls);

      v4l2object->extra_controls = s ? gst_structure_copy (s) : NULL;
      if (GST_V4L2_IS_OPEN (v4l2object))
        gst_v4l2_set_controls (v4l2object, v4l2object->extra_controls);
      break;
    }
    case PROP_PIXEL_ASPECT_RATIO:
      if (v4l2object->par) {
        g_value_unset (v4l2object->par);
        g_free (v4l2object->par);
      }
      v4l2object->par = g_new0 (GValue, 1);
      g_value_init (v4l2object->par, GST_TYPE_FRACTION);
      if (!g_value_transform (value, v4l2object->par)) {
        g_warning ("Could not transform string to aspect ratio");
        gst_value_set_fraction (v4l2object->par, 1, 1);
      }

      GST_DEBUG_OBJECT (v4l2object->dbg_obj, "set PAR to %d/%d",
          gst_value_get_fraction_numerator (v4l2object->par),
          gst_value_get_fraction_denominator (v4l2object->par));
      break;
    case PROP_FORCE_ASPECT_RATIO:
      v4l2object->keep_aspect = g_value_get_boolean (value);
      break;
    case PROP_FORCE_NTSC_TV:
      v4l2object->force_ntsc_tv = g_value_get_boolean (value);
      break;
    default:
      return FALSE;
      break;
  }
  return TRUE;
}


gboolean
gst_v4l2_object_get_property_helper (GstV4l2Object * v4l2object,
    guint prop_id, GValue * value, GParamSpec * pspec)
{
  switch (prop_id) {
    case PROP_DEVICE:
      g_value_set_string (value, v4l2object->videodev);
      break;
    case PROP_DEVICE_NAME:
    {
      const guchar *name = NULL;

      if (GST_V4L2_IS_OPEN (v4l2object))
        name = v4l2object->vcap.card;

      g_value_set_string (value, (gchar *) name);
      break;
    }
    case PROP_DEVICE_FD:
    {
      if (GST_V4L2_IS_OPEN (v4l2object))
        g_value_set_int (value, v4l2object->video_fd);
      else
        g_value_set_int (value, DEFAULT_PROP_DEVICE_FD);
      break;
    }
    case PROP_FLAGS:
    {
      guint flags = 0;

      if (GST_V4L2_IS_OPEN (v4l2object)) {
        flags |= v4l2object->device_caps &
            (V4L2_CAP_VIDEO_CAPTURE |
            V4L2_CAP_VIDEO_OUTPUT |
            V4L2_CAP_VIDEO_OVERLAY |
            V4L2_CAP_VBI_CAPTURE |
            V4L2_CAP_VBI_OUTPUT | V4L2_CAP_TUNER | V4L2_CAP_AUDIO);

        if (v4l2object->device_caps & V4L2_CAP_VIDEO_CAPTURE_MPLANE)
          flags |= V4L2_CAP_VIDEO_CAPTURE;

        if (v4l2object->device_caps & V4L2_CAP_VIDEO_OUTPUT_MPLANE)
          flags |= V4L2_CAP_VIDEO_OUTPUT;
      }
      g_value_set_flags (value, flags);
      break;
    }
    case PROP_BRIGHTNESS:
    case PROP_CONTRAST:
    case PROP_SATURATION:
    case PROP_HUE:
    {
      gint cid = gst_v4l2_object_prop_to_cid (prop_id);

      if (cid != -1) {
        if (GST_V4L2_IS_OPEN (v4l2object)) {
          gint v;
          if (gst_v4l2_get_attribute (v4l2object, cid, &v)) {
            g_value_set_int (value, v);
          }
        }
      }
      return TRUE;
    }
      break;
    case PROP_TV_NORM:
      g_value_set_enum (value, v4l2object->tv_norm);
      break;
    case PROP_IO_MODE:
      g_value_set_enum (value, v4l2object->req_mode);
      break;
    case PROP_CAPTURE_IO_MODE:
      g_return_val_if_fail (!V4L2_TYPE_IS_OUTPUT (v4l2object->type), FALSE);
      g_value_set_enum (value, v4l2object->req_mode);
      break;
    case PROP_OUTPUT_IO_MODE:
      g_return_val_if_fail (V4L2_TYPE_IS_OUTPUT (v4l2object->type), FALSE);
      g_value_set_enum (value, v4l2object->req_mode);
      break;
    case PROP_EXTRA_CONTROLS:
      gst_value_set_structure (value, v4l2object->extra_controls);
      break;
    case PROP_PIXEL_ASPECT_RATIO:
      if (v4l2object->par)
        g_value_transform (v4l2object->par, value);
      break;
    case PROP_FORCE_ASPECT_RATIO:
      g_value_set_boolean (value, v4l2object->keep_aspect);
      break;
    case PROP_FORCE_NTSC_TV:
      g_value_set_boolean (value, v4l2object->force_ntsc_tv);
      break;
    default:
      return FALSE;
      break;
  }
  return TRUE;
}

static void
gst_v4l2_get_driver_min_buffers (GstV4l2Object * v4l2object)
{
  struct v4l2_control control = { 0, };

  g_return_if_fail (GST_V4L2_IS_OPEN (v4l2object));

  if (V4L2_TYPE_IS_OUTPUT (v4l2object->type))
    control.id = V4L2_CID_MIN_BUFFERS_FOR_OUTPUT;
  else
    control.id = V4L2_CID_MIN_BUFFERS_FOR_CAPTURE;

  if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_G_CTRL, &control) == 0) {
    GST_DEBUG_OBJECT (v4l2object->dbg_obj,
        "driver requires a minimum of %d buffers", control.value);
    v4l2object->min_buffers = control.value;
  } else {
    v4l2object->min_buffers = 0;
  }
}

static void
gst_v4l2_set_defaults (GstV4l2Object * v4l2object)
{
  GstTunerNorm *norm = NULL;
  GstTunerChannel *channel = NULL;
  GstTuner *tuner;

  if (!GST_IS_TUNER (v4l2object->element))
    return;

  tuner = GST_TUNER (v4l2object->element);

  if (v4l2object->tv_norm)
    norm = gst_v4l2_tuner_get_norm_by_std_id (v4l2object, v4l2object->tv_norm);
  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "tv_norm=0x%" G_GINT64_MODIFIER "x, "
      "norm=%p", (guint64) v4l2object->tv_norm, norm);
  if (norm) {
    gst_tuner_set_norm (tuner, norm);
  } else {
    norm =
        GST_TUNER_NORM (gst_tuner_get_norm (GST_TUNER (v4l2object->element)));
    if (norm) {
      v4l2object->tv_norm =
          gst_v4l2_tuner_get_std_id_by_norm (v4l2object, norm);
      gst_tuner_norm_changed (tuner, norm);
    }
  }

  if (v4l2object->channel)
    channel = gst_tuner_find_channel_by_name (tuner, v4l2object->channel);
  if (channel) {
    gst_tuner_set_channel (tuner, channel);
  } else {
    channel =
        GST_TUNER_CHANNEL (gst_tuner_get_channel (GST_TUNER
            (v4l2object->element)));
    if (channel) {
      g_free (v4l2object->channel);
      v4l2object->channel = g_strdup (channel->label);
      gst_tuner_channel_changed (tuner, channel);
    }
  }

  if (channel
      && GST_TUNER_CHANNEL_HAS_FLAG (channel, GST_TUNER_CHANNEL_FREQUENCY)) {
    if (v4l2object->frequency != 0) {
      gst_tuner_set_frequency (tuner, channel, v4l2object->frequency);
    } else {
      v4l2object->frequency = gst_tuner_get_frequency (tuner, channel);
      if (v4l2object->frequency == 0) {
        /* guess */
        gst_tuner_set_frequency (tuner, channel, 1000);
      } else {
      }
    }
  }
}

gboolean
gst_v4l2_object_open (GstV4l2Object * v4l2object)
{
  if (gst_v4l2_open (v4l2object))
    gst_v4l2_set_defaults (v4l2object);
  else
    return FALSE;

  return TRUE;
}

gboolean
gst_v4l2_object_open_shared (GstV4l2Object * v4l2object, GstV4l2Object * other)
{
  gboolean ret;

  ret = gst_v4l2_dup (v4l2object, other);

  return ret;
}

gboolean
gst_v4l2_object_close (GstV4l2Object * v4l2object)
{
  if (!gst_v4l2_close (v4l2object))
    return FALSE;

  gst_caps_replace (&v4l2object->probed_caps, NULL);

  /* reset our copy of the device caps */
  v4l2object->device_caps = 0;

  if (v4l2object->formats) {
    gst_v4l2_object_clear_format_list (v4l2object);
  }

  if (v4l2object->par) {
    g_value_unset (v4l2object->par);
    g_free (v4l2object->par);
    v4l2object->par = NULL;
  }

  if (v4l2object->channel) {
    g_free (v4l2object->channel);
    v4l2object->channel = NULL;
  }

  return TRUE;
}

static struct v4l2_fmtdesc *
gst_v4l2_object_get_format_from_fourcc (GstV4l2Object * v4l2object,
    guint32 fourcc)
{
  struct v4l2_fmtdesc *fmt;
  GSList *walk;

  if (fourcc == 0)
    return NULL;

  walk = gst_v4l2_object_get_format_list (v4l2object);
  while (walk) {
    fmt = (struct v4l2_fmtdesc *) walk->data;
    if (fmt->pixelformat == fourcc)
      return fmt;
    /* special case for jpeg */
    if (fmt->pixelformat == V4L2_PIX_FMT_MJPEG ||
        fmt->pixelformat == V4L2_PIX_FMT_JPEG ||
        fmt->pixelformat == V4L2_PIX_FMT_PJPG) {
      if (fourcc == V4L2_PIX_FMT_JPEG || fourcc == V4L2_PIX_FMT_MJPEG ||
          fourcc == V4L2_PIX_FMT_PJPG) {
        return fmt;
      }
    }
    walk = g_slist_next (walk);
  }

  return NULL;
}



/* complete made up ranking, the values themselves are meaningless */
/* These ranks MUST be X such that X<<15 fits on a signed int - see
   the comment at the end of gst_v4l2_object_format_get_rank. */
#define YUV_BASE_RANK     1000
#define JPEG_BASE_RANK     500
#define DV_BASE_RANK       200
#define RGB_BASE_RANK      100
#define YUV_ODD_BASE_RANK   50
#define RGB_ODD_BASE_RANK   25
#define BAYER_BASE_RANK     15
#define S910_BASE_RANK      10
#define GREY_BASE_RANK       5
#define PWC_BASE_RANK        1

static gint
gst_v4l2_object_format_get_rank (const struct v4l2_fmtdesc *fmt)
{
  guint32 fourcc = fmt->pixelformat;
  gboolean emulated = ((fmt->flags & V4L2_FMT_FLAG_EMULATED) != 0);
  gint rank = 0;

  switch (fourcc) {
    case V4L2_PIX_FMT_MJPEG:
    case V4L2_PIX_FMT_PJPG:
      rank = JPEG_BASE_RANK;
      break;
    case V4L2_PIX_FMT_JPEG:
      rank = JPEG_BASE_RANK + 1;
      break;
    case V4L2_PIX_FMT_MPEG:    /* MPEG          */
      rank = JPEG_BASE_RANK + 2;
      break;

    case V4L2_PIX_FMT_RGB332:
    case V4L2_PIX_FMT_ARGB555:
    case V4L2_PIX_FMT_XRGB555:
    case V4L2_PIX_FMT_RGB555:
    case V4L2_PIX_FMT_ARGB555X:
    case V4L2_PIX_FMT_XRGB555X:
    case V4L2_PIX_FMT_RGB555X:
    case V4L2_PIX_FMT_BGR666:
    case V4L2_PIX_FMT_RGB565:
    case V4L2_PIX_FMT_RGB565X:
    case V4L2_PIX_FMT_RGB444:
    case V4L2_PIX_FMT_Y4:
    case V4L2_PIX_FMT_Y6:
    case V4L2_PIX_FMT_Y10:
    case V4L2_PIX_FMT_Y12:
    case V4L2_PIX_FMT_Y10BPACK:
    case V4L2_PIX_FMT_YUV555:
    case V4L2_PIX_FMT_YUV565:
    case V4L2_PIX_FMT_YUV32:
    case V4L2_PIX_FMT_NV12MT_16X16:
    case V4L2_PIX_FMT_NV42:
    case V4L2_PIX_FMT_H264_MVC:
      rank = RGB_ODD_BASE_RANK;
      break;

    case V4L2_PIX_FMT_RGB24:
    case V4L2_PIX_FMT_BGR24:
      rank = RGB_BASE_RANK - 1;
      break;

    case V4L2_PIX_FMT_RGB32:
    case V4L2_PIX_FMT_BGR32:
    case V4L2_PIX_FMT_ABGR32:
    case V4L2_PIX_FMT_XBGR32:
    case V4L2_PIX_FMT_ARGB32:
    case V4L2_PIX_FMT_XRGB32:
      rank = RGB_BASE_RANK;
      break;

    case V4L2_PIX_FMT_GREY:    /*  8  Greyscale     */
      rank = GREY_BASE_RANK;
      break;

    case V4L2_PIX_FMT_NV12:    /* 12  Y/CbCr 4:2:0  */
    case V4L2_PIX_FMT_NV12M:   /* Same as NV12      */
    case V4L2_PIX_FMT_NV12MT:  /* NV12 64x32 tile   */
    case V4L2_PIX_FMT_NV21:    /* 12  Y/CrCb 4:2:0  */
    case V4L2_PIX_FMT_NV21M:   /* Same as NV21      */
    case V4L2_PIX_FMT_YYUV:    /* 16  YUV 4:2:2     */
    case V4L2_PIX_FMT_HI240:   /*  8  8-bit color   */
    case V4L2_PIX_FMT_NV16:    /* 16  Y/CbCr 4:2:2  */
    case V4L2_PIX_FMT_NV16M:   /* Same as NV16      */
    case V4L2_PIX_FMT_NV61:    /* 16  Y/CrCb 4:2:2  */
    case V4L2_PIX_FMT_NV61M:   /* Same as NV61      */
    case V4L2_PIX_FMT_NV24:    /* 24  Y/CrCb 4:4:4  */
    case V4L2_PIX_FMT_XV15:
    case V4L2_PIX_FMT_XV20:
      rank = YUV_ODD_BASE_RANK;
      break;

    case V4L2_PIX_FMT_YVU410:  /* YVU9,  9 bits per pixel */
      rank = YUV_BASE_RANK + 3;
      break;
    case V4L2_PIX_FMT_YUV410:  /* YUV9,  9 bits per pixel */
      rank = YUV_BASE_RANK + 2;
      break;
    case V4L2_PIX_FMT_YUV420:  /* I420, 12 bits per pixel */
    case V4L2_PIX_FMT_YUV420M:
      rank = YUV_BASE_RANK + 7;
      break;
    case V4L2_PIX_FMT_YUYV:    /* YUY2, 16 bits per pixel */
      rank = YUV_BASE_RANK + 10;
      break;
    case V4L2_PIX_FMT_YVU420:  /* YV12, 12 bits per pixel */
      rank = YUV_BASE_RANK + 6;
      break;
    case V4L2_PIX_FMT_UYVY:    /* UYVY, 16 bits per pixel */
      rank = YUV_BASE_RANK + 9;
      break;
    case V4L2_PIX_FMT_YUV444:
      rank = YUV_BASE_RANK + 6;
      break;
    case V4L2_PIX_FMT_Y41P:    /* Y41P, 12 bits per pixel */
      rank = YUV_BASE_RANK + 5;
      break;
    case V4L2_PIX_FMT_YUV411P: /* Y41B, 12 bits per pixel */
      rank = YUV_BASE_RANK + 4;
      break;
    case V4L2_PIX_FMT_YUV422P: /* Y42B, 16 bits per pixel */
      rank = YUV_BASE_RANK + 8;
      break;

    case V4L2_PIX_FMT_DV:
      rank = DV_BASE_RANK;
      break;

    case V4L2_PIX_FMT_WNVA:    /* Winnov hw compres */
      rank = 0;
      break;

    case V4L2_PIX_FMT_SBGGR8:
    case V4L2_PIX_FMT_SGBRG8:
    case V4L2_PIX_FMT_SGRBG8:
    case V4L2_PIX_FMT_SRGGB8:
      rank = BAYER_BASE_RANK;
      break;

    case V4L2_PIX_FMT_SN9C10X:
      rank = S910_BASE_RANK;
      break;

    case V4L2_PIX_FMT_PWC1:
      rank = PWC_BASE_RANK;
      break;
    case V4L2_PIX_FMT_PWC2:
      rank = PWC_BASE_RANK;
      break;

    default:
      rank = 0;
      break;
  }

  /* All ranks are below 1<<15 so a shift by 15
   * will a) make all non-emulated formats larger
   * than emulated and b) will not overflow
   */
  if (!emulated)
    rank <<= 15;

  return rank;
}



static gint
format_cmp_func (gconstpointer a, gconstpointer b)
{
  const struct v4l2_fmtdesc *fa = a;
  const struct v4l2_fmtdesc *fb = b;

  if (fa->pixelformat == fb->pixelformat)
    return 0;

  return gst_v4l2_object_format_get_rank (fb) -
      gst_v4l2_object_format_get_rank (fa);
}

/******************************************************
 * gst_v4l2_object_fill_format_list():
 *   create list of supported capture formats
 * return value: TRUE on success, FALSE on error
 ******************************************************/
static gboolean
gst_v4l2_object_fill_format_list (GstV4l2Object * v4l2object,
    enum v4l2_buf_type type)
{
  gint n;
  struct v4l2_fmtdesc *format;

  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "getting src format enumerations");

  /* format enumeration */
  for (n = 0;; n++) {
    format = g_new0 (struct v4l2_fmtdesc, 1);

    format->index = n;
    format->type = type;

    if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_ENUM_FMT, format) < 0) {
      if (errno == EINVAL) {
        g_free (format);
        break;                  /* end of enumeration */
      } else {
        goto failed;
      }
    }

    GST_LOG_OBJECT (v4l2object->dbg_obj, "index:       %u", format->index);
    GST_LOG_OBJECT (v4l2object->dbg_obj, "type:        %d", format->type);
    GST_LOG_OBJECT (v4l2object->dbg_obj, "flags:       %08x", format->flags);
    GST_LOG_OBJECT (v4l2object->dbg_obj, "description: '%s'",
        format->description);
    GST_LOG_OBJECT (v4l2object->dbg_obj, "pixelformat: %" GST_FOURCC_FORMAT,
        GST_FOURCC_ARGS (format->pixelformat));

    /* sort formats according to our preference;  we do this, because caps
     * are probed in the order the formats are in the list, and the order of
     * formats in the final probed caps matters for things like fixation */
    v4l2object->formats = g_slist_insert_sorted (v4l2object->formats, format,
        (GCompareFunc) format_cmp_func);
  }

#ifndef GST_DISABLE_GST_DEBUG
  {
    GSList *l;

    GST_INFO_OBJECT (v4l2object->dbg_obj, "got %d format(s):", n);
    for (l = v4l2object->formats; l != NULL; l = l->next) {
      format = l->data;

      GST_INFO_OBJECT (v4l2object->dbg_obj,
          "  %" GST_FOURCC_FORMAT "%s", GST_FOURCC_ARGS (format->pixelformat),
          ((format->flags & V4L2_FMT_FLAG_EMULATED)) ? " (emulated)" : "");
    }
  }
#endif

  return TRUE;

  /* ERRORS */
failed:
  {
    g_free (format);

    if (v4l2object->element)
      return FALSE;

    GST_ELEMENT_ERROR (v4l2object->element, RESOURCE, SETTINGS,
        (_("Failed to enumerate possible video formats device '%s' can work "
                "with"), v4l2object->videodev),
        ("Failed to get number %d in pixelformat enumeration for %s. (%d - %s)",
            n, v4l2object->videodev, errno, g_strerror (errno)));

    return FALSE;
  }
}

/*
  * Get the list of supported capture formats, a list of
  * <code>struct v4l2_fmtdesc</code>.
  */
static GSList *
gst_v4l2_object_get_format_list (GstV4l2Object * v4l2object)
{
  if (!v4l2object->formats) {

    /* check usual way */
    gst_v4l2_object_fill_format_list (v4l2object, v4l2object->type);

    /* if our driver supports multi-planar
     * and if formats are still empty then we can workaround driver bug
     * by also looking up formats as if our device was not supporting
     * multiplanar */
    if (!v4l2object->formats) {
      switch (v4l2object->type) {
        case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
          gst_v4l2_object_fill_format_list (v4l2object,
              V4L2_BUF_TYPE_VIDEO_CAPTURE);
          break;

        case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
          gst_v4l2_object_fill_format_list (v4l2object,
              V4L2_BUF_TYPE_VIDEO_OUTPUT);
          break;

        default:
          break;
      }
    }
  }
  return v4l2object->formats;
}

static GstVideoFormat
gst_v4l2_object_v4l2fourcc_to_video_format (guint32 fourcc)
{
  GstVideoFormat format;

  switch (fourcc) {
    case V4L2_PIX_FMT_GREY:    /*  8  Greyscale     */
      format = GST_VIDEO_FORMAT_GRAY8;
      break;
    case V4L2_PIX_FMT_Y16:
      format = GST_VIDEO_FORMAT_GRAY16_LE;
      break;
    case V4L2_PIX_FMT_Y16_BE:
      format = GST_VIDEO_FORMAT_GRAY16_BE;
      break;
    case V4L2_PIX_FMT_XRGB555:
    case V4L2_PIX_FMT_RGB555:
      format = GST_VIDEO_FORMAT_RGB15;
      break;
    case V4L2_PIX_FMT_XRGB555X:
    case V4L2_PIX_FMT_RGB555X:
      format = GST_VIDEO_FORMAT_BGR15;
      break;
    case V4L2_PIX_FMT_RGB565:
      format = GST_VIDEO_FORMAT_RGB16;
      break;
    case V4L2_PIX_FMT_RGB24:
      format = GST_VIDEO_FORMAT_RGB;
      break;
    case V4L2_PIX_FMT_BGR24:
      format = GST_VIDEO_FORMAT_BGR;
      break;
    case V4L2_PIX_FMT_XRGB32:
    case V4L2_PIX_FMT_RGB32:
      format = GST_VIDEO_FORMAT_xRGB;
      break;
    case V4L2_PIX_FMT_XBGR32:
    case V4L2_PIX_FMT_BGR32:
      format = GST_VIDEO_FORMAT_BGRx;
      break;
    case V4L2_PIX_FMT_ABGR32:
      format = GST_VIDEO_FORMAT_BGRA;
      break;
    case V4L2_PIX_FMT_ARGB32:
      format = GST_VIDEO_FORMAT_ARGB;
      break;
    case V4L2_PIX_FMT_NV12:
    case V4L2_PIX_FMT_NV12M:
      format = GST_VIDEO_FORMAT_NV12;
      break;
    case V4L2_PIX_FMT_NV12MT:
      format = GST_VIDEO_FORMAT_NV12_64Z32;
      break;
    case V4L2_PIX_FMT_NV21:
    case V4L2_PIX_FMT_NV21M:
      format = GST_VIDEO_FORMAT_NV21;
      break;
    case V4L2_PIX_FMT_YVU410:
      format = GST_VIDEO_FORMAT_YVU9;
      break;
    case V4L2_PIX_FMT_YUV410:
      format = GST_VIDEO_FORMAT_YUV9;
      break;
    case V4L2_PIX_FMT_YUV420:
    case V4L2_PIX_FMT_YUV420M:
      format = GST_VIDEO_FORMAT_I420;
      break;
    case V4L2_PIX_FMT_YUYV:
      format = GST_VIDEO_FORMAT_YUY2;
      break;
    case V4L2_PIX_FMT_YVU420:
      format = GST_VIDEO_FORMAT_YV12;
      break;
    case V4L2_PIX_FMT_UYVY:
      format = GST_VIDEO_FORMAT_UYVY;
      break;
    case V4L2_PIX_FMT_YUV411P:
      format = GST_VIDEO_FORMAT_Y41B;
      break;
    case V4L2_PIX_FMT_YUV422P:
      format = GST_VIDEO_FORMAT_Y42B;
      break;
    case V4L2_PIX_FMT_YVYU:
      format = GST_VIDEO_FORMAT_YVYU;
      break;
    case V4L2_PIX_FMT_NV16:
    case V4L2_PIX_FMT_NV16M:
      format = GST_VIDEO_FORMAT_NV16;
      break;
    case V4L2_PIX_FMT_NV61:
    case V4L2_PIX_FMT_NV61M:
      format = GST_VIDEO_FORMAT_NV61;
      break;
    case V4L2_PIX_FMT_NV24:
      format = GST_VIDEO_FORMAT_NV24;
      break;
    case V4L2_PIX_FMT_XV15:
      format = GST_VIDEO_FORMAT_NV12_10LE32;
      break;
    case V4L2_PIX_FMT_XV20:
      format = GST_VIDEO_FORMAT_NV16_10LE32;
      break;
    default:
      format = GST_VIDEO_FORMAT_UNKNOWN;
      break;
  }

  return format;
}

static gboolean
gst_v4l2_object_v4l2fourcc_is_rgb (guint32 fourcc)
{
  gboolean ret = FALSE;

  switch (fourcc) {
    case V4L2_PIX_FMT_XRGB555:
    case V4L2_PIX_FMT_RGB555:
    case V4L2_PIX_FMT_XRGB555X:
    case V4L2_PIX_FMT_RGB555X:
    case V4L2_PIX_FMT_RGB565:
    case V4L2_PIX_FMT_RGB24:
    case V4L2_PIX_FMT_BGR24:
    case V4L2_PIX_FMT_XRGB32:
    case V4L2_PIX_FMT_RGB32:
    case V4L2_PIX_FMT_XBGR32:
    case V4L2_PIX_FMT_BGR32:
    case V4L2_PIX_FMT_ABGR32:
    case V4L2_PIX_FMT_ARGB32:
    case V4L2_PIX_FMT_SBGGR8:
    case V4L2_PIX_FMT_SGBRG8:
    case V4L2_PIX_FMT_SGRBG8:
    case V4L2_PIX_FMT_SRGGB8:
      ret = TRUE;
      break;
    default:
      break;
  }

  return ret;
}

static GstStructure *
gst_v4l2_object_v4l2fourcc_to_bare_struct (guint32 fourcc)
{
  GstStructure *structure = NULL;

  switch (fourcc) {
    case V4L2_PIX_FMT_MJPEG:   /* Motion-JPEG */
    case V4L2_PIX_FMT_PJPG:    /* Progressive-JPEG */
    case V4L2_PIX_FMT_JPEG:    /* JFIF JPEG */
      structure = gst_structure_new_empty ("image/jpeg");
      break;
    case V4L2_PIX_FMT_MPEG1:
      structure = gst_structure_new ("video/mpeg",
          "mpegversion", G_TYPE_INT, 2, NULL);
      break;
    case V4L2_PIX_FMT_MPEG2:
      structure = gst_structure_new ("video/mpeg",
          "mpegversion", G_TYPE_INT, 2, NULL);
      break;
    case V4L2_PIX_FMT_MPEG4:
    case V4L2_PIX_FMT_XVID:
      structure = gst_structure_new ("video/mpeg",
          "mpegversion", G_TYPE_INT, 4, "systemstream",
          G_TYPE_BOOLEAN, FALSE, NULL);
      break;
    case V4L2_PIX_FMT_FWHT:
      structure = gst_structure_new_empty ("video/x-fwht");
      break;
    case V4L2_PIX_FMT_H263:
      structure = gst_structure_new ("video/x-h263",
          "variant", G_TYPE_STRING, "itu", NULL);
      break;
    case V4L2_PIX_FMT_H264:    /* H.264 */
      structure = gst_structure_new ("video/x-h264",
          "stream-format", G_TYPE_STRING, "byte-stream", "alignment",
          G_TYPE_STRING, "au", NULL);
      break;
    case V4L2_PIX_FMT_H264_NO_SC:
      structure = gst_structure_new ("video/x-h264",
          "stream-format", G_TYPE_STRING, "avc", "alignment",
          G_TYPE_STRING, "au", NULL);
      break;
    case V4L2_PIX_FMT_HEVC:    /* H.265 */
      structure = gst_structure_new ("video/x-h265",
          "stream-format", G_TYPE_STRING, "byte-stream", "alignment",
          G_TYPE_STRING, "au", NULL);
      break;
    case V4L2_PIX_FMT_VC1_ANNEX_G:
    case V4L2_PIX_FMT_VC1_ANNEX_L:
      structure = gst_structure_new ("video/x-wmv",
          "wmvversion", G_TYPE_INT, 3, "format", G_TYPE_STRING, "WVC1", NULL);
      break;
    case V4L2_PIX_FMT_VP8:
      structure = gst_structure_new_empty ("video/x-vp8");
      break;
    case V4L2_PIX_FMT_VP9:
      structure = gst_structure_new_empty ("video/x-vp9");
      break;
    case V4L2_PIX_FMT_GREY:    /*  8  Greyscale     */
    case V4L2_PIX_FMT_Y16:
    case V4L2_PIX_FMT_Y16_BE:
    case V4L2_PIX_FMT_XRGB555:
    case V4L2_PIX_FMT_RGB555:
    case V4L2_PIX_FMT_XRGB555X:
    case V4L2_PIX_FMT_RGB555X:
    case V4L2_PIX_FMT_RGB565:
    case V4L2_PIX_FMT_RGB24:
    case V4L2_PIX_FMT_BGR24:
    case V4L2_PIX_FMT_RGB32:
    case V4L2_PIX_FMT_XRGB32:
    case V4L2_PIX_FMT_ARGB32:
    case V4L2_PIX_FMT_BGR32:
    case V4L2_PIX_FMT_XBGR32:
    case V4L2_PIX_FMT_ABGR32:
    case V4L2_PIX_FMT_NV12:    /* 12  Y/CbCr 4:2:0  */
    case V4L2_PIX_FMT_NV12M:
    case V4L2_PIX_FMT_NV12MT:
    case V4L2_PIX_FMT_NV21:    /* 12  Y/CrCb 4:2:0  */
    case V4L2_PIX_FMT_NV21M:
    case V4L2_PIX_FMT_NV16:    /* 16  Y/CbCr 4:2:2  */
    case V4L2_PIX_FMT_NV16M:
    case V4L2_PIX_FMT_NV61:    /* 16  Y/CrCb 4:2:2  */
    case V4L2_PIX_FMT_NV61M:
    case V4L2_PIX_FMT_NV24:    /* 24  Y/CrCb 4:4:4  */
    case V4L2_PIX_FMT_YVU410:
    case V4L2_PIX_FMT_YUV410:
    case V4L2_PIX_FMT_YUV420:  /* I420/IYUV */
    case V4L2_PIX_FMT_YUV420M:
    case V4L2_PIX_FMT_YUYV:
    case V4L2_PIX_FMT_YVU420:
    case V4L2_PIX_FMT_UYVY:
    case V4L2_PIX_FMT_YUV422P:
    case V4L2_PIX_FMT_YVYU:
    case V4L2_PIX_FMT_YUV411P:
    case V4L2_PIX_FMT_XV15:
    case V4L2_PIX_FMT_XV20:{
      GstVideoFormat format;
      format = gst_v4l2_object_v4l2fourcc_to_video_format (fourcc);
      if (format != GST_VIDEO_FORMAT_UNKNOWN)
        structure = gst_structure_new ("video/x-raw",
            "format", G_TYPE_STRING, gst_video_format_to_string (format), NULL);
      break;
    }
    case V4L2_PIX_FMT_DV:
      structure =
          gst_structure_new ("video/x-dv", "systemstream", G_TYPE_BOOLEAN, TRUE,
          NULL);
      break;
    case V4L2_PIX_FMT_MPEG:    /* MPEG          */
      structure = gst_structure_new ("video/mpegts",
          "systemstream", G_TYPE_BOOLEAN, TRUE, NULL);
      break;
    case V4L2_PIX_FMT_WNVA:    /* Winnov hw compres */
      break;
    case V4L2_PIX_FMT_SBGGR8:
    case V4L2_PIX_FMT_SGBRG8:
    case V4L2_PIX_FMT_SGRBG8:
    case V4L2_PIX_FMT_SRGGB8:
      structure = gst_structure_new ("video/x-bayer", "format", G_TYPE_STRING,
          fourcc == V4L2_PIX_FMT_SBGGR8 ? "bggr" :
          fourcc == V4L2_PIX_FMT_SGBRG8 ? "gbrg" :
          fourcc == V4L2_PIX_FMT_SGRBG8 ? "grbg" :
          /* fourcc == V4L2_PIX_FMT_SRGGB8 ? */ "rggb", NULL);
      break;
    case V4L2_PIX_FMT_SN9C10X:
      structure = gst_structure_new_empty ("video/x-sonix");
      break;
    case V4L2_PIX_FMT_PWC1:
      structure = gst_structure_new_empty ("video/x-pwc1");
      break;
    case V4L2_PIX_FMT_PWC2:
      structure = gst_structure_new_empty ("video/x-pwc2");
      break;
    case V4L2_PIX_FMT_RGB332:
    case V4L2_PIX_FMT_BGR666:
    case V4L2_PIX_FMT_ARGB555X:
    case V4L2_PIX_FMT_RGB565X:
    case V4L2_PIX_FMT_RGB444:
    case V4L2_PIX_FMT_YYUV:    /* 16  YUV 4:2:2     */
    case V4L2_PIX_FMT_HI240:   /*  8  8-bit color   */
    case V4L2_PIX_FMT_Y4:
    case V4L2_PIX_FMT_Y6:
    case V4L2_PIX_FMT_Y10:
    case V4L2_PIX_FMT_Y12:
    case V4L2_PIX_FMT_Y10BPACK:
    case V4L2_PIX_FMT_YUV444:
    case V4L2_PIX_FMT_YUV555:
    case V4L2_PIX_FMT_YUV565:
    case V4L2_PIX_FMT_Y41P:
    case V4L2_PIX_FMT_YUV32:
    case V4L2_PIX_FMT_NV12MT_16X16:
    case V4L2_PIX_FMT_NV42:
    case V4L2_PIX_FMT_H264_MVC:
    default:
      GST_DEBUG ("Unsupported fourcc 0x%08x %" GST_FOURCC_FORMAT,
          fourcc, GST_FOURCC_ARGS (fourcc));
      break;
  }

  return structure;
}

GstStructure *
gst_v4l2_object_v4l2fourcc_to_structure (guint32 fourcc)
{
  GstStructure *template;
  gint i;

  template = gst_v4l2_object_v4l2fourcc_to_bare_struct (fourcc);

  if (template == NULL)
    goto done;

  for (i = 0; i < GST_V4L2_FORMAT_COUNT; i++) {
    if (gst_v4l2_formats[i].format != fourcc)
      continue;

    if (gst_v4l2_formats[i].dimensions) {
      gst_structure_set (template,
          "width", GST_TYPE_INT_RANGE, 1, GST_V4L2_MAX_SIZE,
          "height", GST_TYPE_INT_RANGE, 1, GST_V4L2_MAX_SIZE,
          "framerate", GST_TYPE_FRACTION_RANGE, 0, 1, G_MAXINT, 1, NULL);
    }
    break;
  }

done:
  return template;
}

#define SYNC_IP_DEV_ENCODER "/dev/xlnxsync0"

static gboolean
xlnx_ll_supported (void)
{
  return g_file_test (SYNC_IP_DEV_ENCODER, G_FILE_TEST_EXISTS);
}

static GstCaps *
gst_v4l2_object_get_caps_helper (GstV4L2FormatFlags flags)
{
  GstStructure *structure;
  GstCaps *caps;
  guint i;

  caps = gst_caps_new_empty ();
  for (i = 0; i < GST_V4L2_FORMAT_COUNT; i++) {

    if ((gst_v4l2_formats[i].flags & flags) == 0)
      continue;

    structure =
        gst_v4l2_object_v4l2fourcc_to_bare_struct (gst_v4l2_formats[i].format);

    if (structure) {
      GstStructure *alt_s = NULL;

      if (gst_v4l2_formats[i].dimensions) {
        gst_structure_set (structure,
            "width", GST_TYPE_INT_RANGE, 1, GST_V4L2_MAX_SIZE,
            "height", GST_TYPE_INT_RANGE, 1, GST_V4L2_MAX_SIZE,
            "framerate", GST_TYPE_FRACTION_RANGE, 0, 1, G_MAXINT, 1, NULL);
      }

      switch (gst_v4l2_formats[i].format) {
        case V4L2_PIX_FMT_RGB32:
          alt_s = gst_structure_copy (structure);
          gst_structure_set (alt_s, "format", G_TYPE_STRING, "ARGB", NULL);
          break;
        case V4L2_PIX_FMT_BGR32:
          alt_s = gst_structure_copy (structure);
          gst_structure_set (alt_s, "format", G_TYPE_STRING, "BGRA", NULL);
        default:
          break;
      }

      gst_caps_append_structure (caps, structure);

      if (alt_s)
        gst_caps_append_structure (caps, alt_s);

      if (gst_structure_has_name (structure, "video/x-raw")) {
        /* Add an 'alternate' variant of the caps with the feature */
        alt_s = gst_structure_copy (structure);
        gst_structure_set (alt_s, "interlace-mode", G_TYPE_STRING, "alternate",
            NULL);

        gst_caps_append_structure (caps, alt_s);
        gst_caps_set_features (caps, gst_caps_get_size (caps) - 1,
            gst_caps_features_new (GST_CAPS_FEATURE_FORMAT_INTERLACED, NULL));
      }
    }
  }

  return gst_caps_simplify (caps);
}

GstCaps *
gst_v4l2_object_get_all_caps (void)
{
  static GstCaps *caps = NULL;

  if (g_once_init_enter (&caps)) {
    GstCaps *all_caps = gst_v4l2_object_get_caps_helper (GST_V4L2_ALL);
    GST_MINI_OBJECT_FLAG_SET (all_caps, GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED);
    g_once_init_leave (&caps, all_caps);
  }

  return caps;
}

GstCaps *
gst_v4l2_object_get_raw_caps (void)
{
  static GstCaps *caps = NULL;

  if (g_once_init_enter (&caps)) {
    GstCaps *raw_caps = gst_v4l2_object_get_caps_helper (GST_V4L2_RAW);
    GST_MINI_OBJECT_FLAG_SET (raw_caps, GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED);
    g_once_init_leave (&caps, raw_caps);
  }

  return caps;
}

GstCaps *
gst_v4l2_object_get_codec_caps (void)
{
  static GstCaps *caps = NULL;

  if (g_once_init_enter (&caps)) {
    GstCaps *codec_caps = gst_v4l2_object_get_caps_helper (GST_V4L2_CODEC);
    GST_MINI_OBJECT_FLAG_SET (codec_caps, GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED);
    g_once_init_leave (&caps, codec_caps);
  }

  return caps;
}

/* collect data for the given caps
 * @caps: given input caps
 * @format: location for the v4l format
 * @w/@h: location for width and height
 * @fps_n/@fps_d: location for framerate
 * @size: location for expected size of the frame or 0 if unknown
 */
static gboolean
gst_v4l2_object_get_caps_info (GstV4l2Object * v4l2object, GstCaps * caps,
    struct v4l2_fmtdesc **format, GstVideoInfo * info)
{
  GstStructure *structure;
  guint32 fourcc = 0, fourcc_nc = 0;
  const gchar *mimetype;
  struct v4l2_fmtdesc *fmt = NULL;

  structure = gst_caps_get_structure (caps, 0);

  mimetype = gst_structure_get_name (structure);

  if (!gst_video_info_from_caps (info, caps))
    goto invalid_format;

  if (g_str_equal (mimetype, "video/x-raw")) {
    switch (GST_VIDEO_INFO_FORMAT (info)) {
      case GST_VIDEO_FORMAT_I420:
        fourcc = V4L2_PIX_FMT_YUV420;
        fourcc_nc = V4L2_PIX_FMT_YUV420M;
        break;
      case GST_VIDEO_FORMAT_YUY2:
        fourcc = V4L2_PIX_FMT_YUYV;
        break;
      case GST_VIDEO_FORMAT_UYVY:
        fourcc = V4L2_PIX_FMT_UYVY;
        break;
      case GST_VIDEO_FORMAT_YV12:
        fourcc = V4L2_PIX_FMT_YVU420;
        break;
      case GST_VIDEO_FORMAT_Y41B:
        fourcc = V4L2_PIX_FMT_YUV411P;
        break;
      case GST_VIDEO_FORMAT_Y42B:
        fourcc = V4L2_PIX_FMT_YUV422P;
        break;
      case GST_VIDEO_FORMAT_NV12:
        fourcc = V4L2_PIX_FMT_NV12;
        fourcc_nc = V4L2_PIX_FMT_NV12M;
        break;
      case GST_VIDEO_FORMAT_NV12_64Z32:
        fourcc_nc = V4L2_PIX_FMT_NV12MT;
        break;
      case GST_VIDEO_FORMAT_NV12_10LE32:
        fourcc = V4L2_PIX_FMT_XV15;
        break;
      case GST_VIDEO_FORMAT_NV16_10LE32:
        fourcc = V4L2_PIX_FMT_XV20;
        break;
      case GST_VIDEO_FORMAT_NV21:
        fourcc = V4L2_PIX_FMT_NV21;
        fourcc_nc = V4L2_PIX_FMT_NV21M;
        break;
      case GST_VIDEO_FORMAT_NV16:
        fourcc = V4L2_PIX_FMT_NV16;
        fourcc_nc = V4L2_PIX_FMT_NV16M;
        break;
      case GST_VIDEO_FORMAT_NV61:
        fourcc = V4L2_PIX_FMT_NV61;
        fourcc_nc = V4L2_PIX_FMT_NV61M;
        break;
      case GST_VIDEO_FORMAT_NV24:
        fourcc = V4L2_PIX_FMT_NV24;
        break;
      case GST_VIDEO_FORMAT_YVYU:
        fourcc = V4L2_PIX_FMT_YVYU;
        break;
      case GST_VIDEO_FORMAT_RGB15:
        fourcc = V4L2_PIX_FMT_RGB555;
        fourcc_nc = V4L2_PIX_FMT_XRGB555;
        break;
      case GST_VIDEO_FORMAT_RGB16:
        fourcc = V4L2_PIX_FMT_RGB565;
        break;
      case GST_VIDEO_FORMAT_RGB:
        fourcc = V4L2_PIX_FMT_RGB24;
        break;
      case GST_VIDEO_FORMAT_BGR:
        fourcc = V4L2_PIX_FMT_BGR24;
        break;
      case GST_VIDEO_FORMAT_xRGB:
        fourcc = V4L2_PIX_FMT_RGB32;
        fourcc_nc = V4L2_PIX_FMT_XRGB32;
        break;
      case GST_VIDEO_FORMAT_ARGB:
        fourcc = V4L2_PIX_FMT_RGB32;
        fourcc_nc = V4L2_PIX_FMT_ARGB32;
        break;
      case GST_VIDEO_FORMAT_BGRx:
        fourcc = V4L2_PIX_FMT_BGR32;
        fourcc_nc = V4L2_PIX_FMT_XBGR32;
        break;
      case GST_VIDEO_FORMAT_BGRA:
        fourcc = V4L2_PIX_FMT_BGR32;
        fourcc_nc = V4L2_PIX_FMT_ABGR32;
        break;
      case GST_VIDEO_FORMAT_GRAY8:
        fourcc = V4L2_PIX_FMT_GREY;
        break;
      case GST_VIDEO_FORMAT_GRAY16_LE:
        fourcc = V4L2_PIX_FMT_Y16;
        break;
      case GST_VIDEO_FORMAT_GRAY16_BE:
        fourcc = V4L2_PIX_FMT_Y16_BE;
        break;
      default:
        break;
    }
  } else {
    if (g_str_equal (mimetype, "video/mpegts")) {
      fourcc = V4L2_PIX_FMT_MPEG;
    } else if (g_str_equal (mimetype, "video/x-dv")) {
      fourcc = V4L2_PIX_FMT_DV;
    } else if (g_str_equal (mimetype, "image/jpeg")) {
      fourcc = V4L2_PIX_FMT_JPEG;
    } else if (g_str_equal (mimetype, "video/mpeg")) {
      gint version;
      if (gst_structure_get_int (structure, "mpegversion", &version)) {
        switch (version) {
          case 1:
            fourcc = V4L2_PIX_FMT_MPEG1;
            break;
          case 2:
            fourcc = V4L2_PIX_FMT_MPEG2;
            break;
          case 4:
            fourcc = V4L2_PIX_FMT_MPEG4;
            fourcc_nc = V4L2_PIX_FMT_XVID;
            break;
          default:
            break;
        }
      }
    } else if (g_str_equal (mimetype, "video/x-fwht")) {
      fourcc = V4L2_PIX_FMT_FWHT;
    } else if (g_str_equal (mimetype, "video/x-h263")) {
      fourcc = V4L2_PIX_FMT_H263;
    } else if (g_str_equal (mimetype, "video/x-h264")) {
      const gchar *stream_format =
          gst_structure_get_string (structure, "stream-format");
      if (g_str_equal (stream_format, "avc"))
        fourcc = V4L2_PIX_FMT_H264_NO_SC;
      else
        fourcc = V4L2_PIX_FMT_H264;
    } else if (g_str_equal (mimetype, "video/x-h265")) {
      fourcc = V4L2_PIX_FMT_HEVC;
    } else if (g_str_equal (mimetype, "video/x-vp8")) {
      fourcc = V4L2_PIX_FMT_VP8;
    } else if (g_str_equal (mimetype, "video/x-vp9")) {
      fourcc = V4L2_PIX_FMT_VP9;
    } else if (g_str_equal (mimetype, "video/x-bayer")) {
      const gchar *format = gst_structure_get_string (structure, "format");
      if (format) {
        if (!g_ascii_strcasecmp (format, "bggr"))
          fourcc = V4L2_PIX_FMT_SBGGR8;
        else if (!g_ascii_strcasecmp (format, "gbrg"))
          fourcc = V4L2_PIX_FMT_SGBRG8;
        else if (!g_ascii_strcasecmp (format, "grbg"))
          fourcc = V4L2_PIX_FMT_SGRBG8;
        else if (!g_ascii_strcasecmp (format, "rggb"))
          fourcc = V4L2_PIX_FMT_SRGGB8;
      }
    } else if (g_str_equal (mimetype, "video/x-sonix")) {
      fourcc = V4L2_PIX_FMT_SN9C10X;
    } else if (g_str_equal (mimetype, "video/x-pwc1")) {
      fourcc = V4L2_PIX_FMT_PWC1;
    } else if (g_str_equal (mimetype, "video/x-pwc2")) {
      fourcc = V4L2_PIX_FMT_PWC2;
    }
  }


  /* Prefer the contiguous if supported */
  v4l2object->prefered_non_contiguous = FALSE;

  if (fourcc)
    fmt = gst_v4l2_object_get_format_from_fourcc (v4l2object, fourcc);
  else if (fourcc == 0)
    goto unhandled_format;

  if (fmt == NULL) {
    fmt = gst_v4l2_object_get_format_from_fourcc (v4l2object, fourcc_nc);
    v4l2object->prefered_non_contiguous = TRUE;
  }

  if (fmt == NULL)
    goto unsupported_format;

  *format = fmt;

  return TRUE;

  /* ERRORS */
invalid_format:
  {
    GST_DEBUG_OBJECT (v4l2object, "invalid format");
    return FALSE;
  }
unhandled_format:
  {
    GST_DEBUG_OBJECT (v4l2object, "unhandled format");
    return FALSE;
  }
unsupported_format:
  {
    GST_DEBUG_OBJECT (v4l2object, "unsupported format");
    return FALSE;
  }
}

static gboolean
gst_v4l2_object_get_nearest_size (GstV4l2Object * v4l2object,
    guint32 pixelformat, gint * width, gint * height);

static void
gst_v4l2_object_add_aspect_ratio (GstV4l2Object * v4l2object, GstStructure * s)
{
  if (v4l2object->keep_aspect && v4l2object->par)
    gst_structure_set_value (s, "pixel-aspect-ratio", v4l2object->par);
}

/* returns TRUE if the value was changed in place, otherwise FALSE */
static gboolean
gst_v4l2src_value_simplify (GValue * val)
{
  /* simplify list of one value to one value */
  if (GST_VALUE_HOLDS_LIST (val) && gst_value_list_get_size (val) == 1) {
    const GValue *list_val;
    GValue new_val = G_VALUE_INIT;

    list_val = gst_value_list_get_value (val, 0);
    g_value_init (&new_val, G_VALUE_TYPE (list_val));
    g_value_copy (list_val, &new_val);
    g_value_unset (val);
    *val = new_val;
    return TRUE;
  }

  return FALSE;
}

static gboolean
gst_v4l2_object_set_low_latency_capture_mode (GstV4l2Object * v4l2object,
    gboolean enable)
{
  struct v4l2_control control = { 0, };

  control.id = V4L2_CID_XILINX_LOW_LATENCY;
  control.value = enable ? XVIP_LOW_LATENCY_ENABLE : XVIP_LOW_LATENCY_DISABLE;

  if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_S_CTRL, &control) != 0) {
    GST_WARNING_OBJECT (v4l2object->dbg_obj,
        "Failed to enable low latency on capture device");
    return FALSE;
  }

  return TRUE;
}

static gboolean
gst_v4l2_object_get_interlace_mode (enum v4l2_field field,
    GstVideoInterlaceMode * interlace_mode)
{
  switch (field) {
    case V4L2_FIELD_ANY:
      GST_ERROR
          ("Driver bug detected - check driver with v4l2-compliance from http://git.linuxtv.org/v4l-utils.git\n");
      /* fallthrough */
    case V4L2_FIELD_NONE:
      *interlace_mode = GST_VIDEO_INTERLACE_MODE_PROGRESSIVE;
      return TRUE;
    case V4L2_FIELD_INTERLACED:
    case V4L2_FIELD_INTERLACED_TB:
    case V4L2_FIELD_INTERLACED_BT:
      *interlace_mode = GST_VIDEO_INTERLACE_MODE_INTERLEAVED;
      return TRUE;
    case V4L2_FIELD_ALTERNATE:
      *interlace_mode = GST_VIDEO_INTERLACE_MODE_ALTERNATE;
      return TRUE;
    default:
      GST_ERROR ("Unknown enum v4l2_field %d", field);
      return FALSE;
  }
}

static gboolean
gst_v4l2_object_get_colorspace (struct v4l2_format *fmt,
    GstVideoColorimetry * cinfo)
{
  gboolean is_rgb =
      gst_v4l2_object_v4l2fourcc_is_rgb (fmt->fmt.pix.pixelformat);
  enum v4l2_colorspace colorspace;
  enum v4l2_quantization range;
  enum v4l2_ycbcr_encoding matrix;
  enum v4l2_xfer_func transfer;
  gboolean ret = TRUE;

  if (V4L2_TYPE_IS_MULTIPLANAR (fmt->type)) {
    colorspace = fmt->fmt.pix_mp.colorspace;
    range = fmt->fmt.pix_mp.quantization;
    matrix = fmt->fmt.pix_mp.ycbcr_enc;
    transfer = fmt->fmt.pix_mp.xfer_func;
  } else {
    colorspace = fmt->fmt.pix.colorspace;
    range = fmt->fmt.pix.quantization;
    matrix = fmt->fmt.pix.ycbcr_enc;
    transfer = fmt->fmt.pix.xfer_func;
  }

  /* First step, set the defaults for each primaries */
  switch (colorspace) {
    case V4L2_COLORSPACE_SMPTE170M:
      cinfo->range = GST_VIDEO_COLOR_RANGE_16_235;
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_BT601;
      cinfo->transfer = GST_VIDEO_TRANSFER_BT709;
      cinfo->primaries = GST_VIDEO_COLOR_PRIMARIES_SMPTE170M;
      break;
    case V4L2_COLORSPACE_REC709:
      cinfo->range = GST_VIDEO_COLOR_RANGE_16_235;
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_BT709;
      cinfo->transfer = GST_VIDEO_TRANSFER_BT709;
      cinfo->primaries = GST_VIDEO_COLOR_PRIMARIES_BT709;
      break;
    case V4L2_COLORSPACE_SRGB:
    case V4L2_COLORSPACE_JPEG:
      cinfo->range = GST_VIDEO_COLOR_RANGE_0_255;
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_BT601;
      cinfo->transfer = GST_VIDEO_TRANSFER_SRGB;
      cinfo->primaries = GST_VIDEO_COLOR_PRIMARIES_BT709;
      break;
    case V4L2_COLORSPACE_OPRGB:
      cinfo->range = GST_VIDEO_COLOR_RANGE_16_235;
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_BT601;
      cinfo->transfer = GST_VIDEO_TRANSFER_ADOBERGB;
      cinfo->primaries = GST_VIDEO_COLOR_PRIMARIES_ADOBERGB;
      break;
    case V4L2_COLORSPACE_BT2020:
      cinfo->range = GST_VIDEO_COLOR_RANGE_16_235;
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_BT2020;
      cinfo->transfer = GST_VIDEO_TRANSFER_BT2020_12;
      cinfo->primaries = GST_VIDEO_COLOR_PRIMARIES_BT2020;
      break;
    case V4L2_COLORSPACE_SMPTE240M:
      cinfo->range = GST_VIDEO_COLOR_RANGE_16_235;
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_SMPTE240M;
      cinfo->transfer = GST_VIDEO_TRANSFER_SMPTE240M;
      cinfo->primaries = GST_VIDEO_COLOR_PRIMARIES_SMPTE240M;
      break;
    case V4L2_COLORSPACE_470_SYSTEM_M:
      cinfo->range = GST_VIDEO_COLOR_RANGE_16_235;
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_BT601;
      cinfo->transfer = GST_VIDEO_TRANSFER_BT709;
      cinfo->primaries = GST_VIDEO_COLOR_PRIMARIES_BT470M;
      break;
    case V4L2_COLORSPACE_470_SYSTEM_BG:
      cinfo->range = GST_VIDEO_COLOR_RANGE_16_235;
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_BT601;
      cinfo->transfer = GST_VIDEO_TRANSFER_BT709;
      cinfo->primaries = GST_VIDEO_COLOR_PRIMARIES_BT470BG;
      break;
    case V4L2_COLORSPACE_RAW:
      /* Explicitly unknown */
      cinfo->range = GST_VIDEO_COLOR_RANGE_UNKNOWN;
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_UNKNOWN;
      cinfo->transfer = GST_VIDEO_TRANSFER_UNKNOWN;
      cinfo->primaries = GST_VIDEO_COLOR_PRIMARIES_UNKNOWN;
      break;
    default:
      GST_DEBUG ("Unknown enum v4l2_colorspace %d", colorspace);
      ret = FALSE;
      break;
  }

  if (!ret)
    goto done;

  /* Second step, apply any custom variation */
  switch (range) {
    case V4L2_QUANTIZATION_FULL_RANGE:
      cinfo->range = GST_VIDEO_COLOR_RANGE_0_255;
      break;
    case V4L2_QUANTIZATION_LIM_RANGE:
      cinfo->range = GST_VIDEO_COLOR_RANGE_16_235;
      break;
    case V4L2_QUANTIZATION_DEFAULT:
      /* replicated V4L2_MAP_QUANTIZATION_DEFAULT macro behavior */
      if (is_rgb && colorspace == V4L2_COLORSPACE_BT2020)
        cinfo->range = GST_VIDEO_COLOR_RANGE_16_235;
      else if (is_rgb || matrix == V4L2_YCBCR_ENC_XV601
          || matrix == V4L2_YCBCR_ENC_XV709
          || colorspace == V4L2_COLORSPACE_JPEG)
        cinfo->range = GST_VIDEO_COLOR_RANGE_0_255;
      else
        cinfo->range = GST_VIDEO_COLOR_RANGE_16_235;
      break;
    default:
      GST_WARNING ("Unknown enum v4l2_quantization value %d", range);
      cinfo->range = GST_VIDEO_COLOR_RANGE_UNKNOWN;
      break;
  }

  switch (matrix) {
    case V4L2_YCBCR_ENC_XV601:
    case V4L2_YCBCR_ENC_SYCC:
      GST_FIXME ("XV601 and SYCC not defined, assuming 601");
      /* fallthrough */
    case V4L2_YCBCR_ENC_601:
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_BT601;
      break;
    case V4L2_YCBCR_ENC_XV709:
      GST_FIXME ("XV709 not defined, assuming 709");
      /* fallthrough */
    case V4L2_YCBCR_ENC_709:
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_BT709;
      break;
    case V4L2_YCBCR_ENC_BT2020_CONST_LUM:
      GST_FIXME ("BT2020 with constant luma is not defined, assuming BT2020");
      /* fallthrough */
    case V4L2_YCBCR_ENC_BT2020:
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_BT2020;
      break;
    case V4L2_YCBCR_ENC_SMPTE240M:
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_SMPTE240M;
      break;
    case V4L2_YCBCR_ENC_DEFAULT:
      /* nothing, just use defaults for colorspace */
      break;
    default:
      GST_WARNING ("Unknown enum v4l2_ycbcr_encoding value %d", matrix);
      cinfo->matrix = GST_VIDEO_COLOR_MATRIX_UNKNOWN;
      break;
  }

  /* Set identity matrix for R'G'B' formats to avoid creating
   * confusion. This though is cosmetic as it's now properly ignored by
   * the video info API and videoconvert. */
  if (is_rgb)
    cinfo->matrix = GST_VIDEO_COLOR_MATRIX_RGB;

  switch (transfer) {
    case V4L2_XFER_FUNC_709:
      if (colorspace == V4L2_COLORSPACE_BT2020 && fmt->fmt.pix.height >= 2160)
        cinfo->transfer = GST_VIDEO_TRANSFER_BT2020_12;
      else
        cinfo->transfer = GST_VIDEO_TRANSFER_BT709;
      break;
    case V4L2_XFER_FUNC_SRGB:
      cinfo->transfer = GST_VIDEO_TRANSFER_SRGB;
      break;
    case V4L2_XFER_FUNC_OPRGB:
      cinfo->transfer = GST_VIDEO_TRANSFER_ADOBERGB;
      break;
    case V4L2_XFER_FUNC_SMPTE240M:
      cinfo->transfer = GST_VIDEO_TRANSFER_SMPTE240M;
      break;
    case V4L2_XFER_FUNC_NONE:
      GST_WARNING
          ("GAMMA 10, 18, 20, 22, 28 transfer functions all share the same V4L2 enumeration. Force caps to be renegotiated with upstream elements' caps");
      ret = FALSE;
      break;
    case V4L2_XFER_FUNC_DEFAULT:
      /* nothing, just use defaults for colorspace */
      break;
    default:
      GST_WARNING ("Unknown enum v4l2_xfer_func value %d", transfer);
      cinfo->transfer = GST_VIDEO_TRANSFER_UNKNOWN;
      break;
  }

done:
  return ret;
}

static int
gst_v4l2_object_try_fmt (GstV4l2Object * v4l2object,
    struct v4l2_format *try_fmt)
{
  int fd = v4l2object->video_fd;
  struct v4l2_format fmt;
  int r;

  memcpy (&fmt, try_fmt, sizeof (fmt));
  r = v4l2object->ioctl (fd, VIDIOC_TRY_FMT, &fmt);

  if (r < 0 && errno == ENOTTY) {
    /* The driver might not implement TRY_FMT, in which case we will try
       S_FMT to probe */
    if (GST_V4L2_IS_ACTIVE (v4l2object))
      goto error;

    memcpy (&fmt, try_fmt, sizeof (fmt));
    r = v4l2object->ioctl (fd, VIDIOC_S_FMT, &fmt);
  }
  memcpy (try_fmt, &fmt, sizeof (fmt));

  return r;

error:
  memcpy (try_fmt, &fmt, sizeof (fmt));
  GST_WARNING_OBJECT (v4l2object->dbg_obj,
      "Unable to try format: %s", g_strerror (errno));
  return r;
}


static void
gst_v4l2_object_add_interlace_mode (GstV4l2Object * v4l2object,
    GstStructure * s, guint32 width, guint32 height, guint32 pixelformat)
{
  struct v4l2_format fmt;
  GValue interlace_formats = { 0, };
  enum v4l2_field formats[] = { V4L2_FIELD_NONE,
    V4L2_FIELD_INTERLACED, V4L2_FIELD_ALTERNATE
  };
  gsize i;
  GstVideoInterlaceMode interlace_mode, prev = -1;

  if (!g_str_equal (gst_structure_get_name (s), "video/x-raw"))
    return;

  if (v4l2object->never_interlaced) {
    gst_structure_set (s, "interlace-mode", G_TYPE_STRING, "progressive", NULL);
    return;
  }

  g_value_init (&interlace_formats, GST_TYPE_LIST);

  /* Try thrice - once for NONE, once for INTERLACED and once for ALTERNATE. */
  for (i = 0; i < G_N_ELEMENTS (formats); i++) {
    memset (&fmt, 0, sizeof (fmt));
    fmt.type = v4l2object->type;
    fmt.fmt.pix.width = width;
    fmt.fmt.pix.height = height;
    fmt.fmt.pix.pixelformat = pixelformat;
    fmt.fmt.pix.field = formats[i];

    if (fmt.fmt.pix.field == V4L2_FIELD_ALTERNATE)
      fmt.fmt.pix.height /= 2;

    if (!v4l2object->skip_try_fmt_probes
        && gst_v4l2_object_try_fmt (v4l2object, &fmt) != 0)
      continue;

    if (gst_v4l2_object_get_interlace_mode (fmt.fmt.pix.field, &interlace_mode)
        && prev != interlace_mode) {
      GValue interlace_enum = { 0, };
      const gchar *mode_string;
      g_value_init (&interlace_enum, G_TYPE_STRING);
      mode_string = gst_video_interlace_mode_to_string (interlace_mode);
      g_value_set_string (&interlace_enum, mode_string);
      gst_value_list_append_and_take_value (&interlace_formats,
          &interlace_enum);
      prev = interlace_mode;
    }
  }

  if (gst_v4l2src_value_simplify (&interlace_formats)
      || gst_value_list_get_size (&interlace_formats) > 0)
    gst_structure_take_value (s, "interlace-mode", &interlace_formats);
  else
    GST_WARNING_OBJECT (v4l2object, "Failed to determine interlace mode");

  return;
}

static void
gst_v4l2_object_fill_colorimetry_list (GValue * list,
    GstVideoColorimetry * cinfo)
{
  GValue colorimetry = G_VALUE_INIT;
  guint size;
  guint i;
  gboolean found = FALSE;

  g_value_init (&colorimetry, G_TYPE_STRING);
  g_value_take_string (&colorimetry, gst_video_colorimetry_to_string (cinfo));

  /* only insert if no duplicate */
  size = gst_value_list_get_size (list);
  for (i = 0; i < size; i++) {
    const GValue *tmp;

    tmp = gst_value_list_get_value (list, i);
    if (gst_value_compare (&colorimetry, tmp) == GST_VALUE_EQUAL) {
      found = TRUE;
      break;
    }
  }

  if (!found)
    gst_value_list_append_and_take_value (list, &colorimetry);
  else
    g_value_unset (&colorimetry);
}

static void
gst_v4l2_object_add_colorspace (GstV4l2Object * v4l2object, GstStructure * s,
    guint32 width, guint32 height, guint32 pixelformat)
{
  struct v4l2_format fmt;
  GValue list = G_VALUE_INIT;
  GstVideoColorimetry cinfo;
  enum v4l2_colorspace req_cspace;

  memset (&fmt, 0, sizeof (fmt));
  fmt.type = v4l2object->type;
  fmt.fmt.pix.width = width;
  fmt.fmt.pix.height = height;
  fmt.fmt.pix.pixelformat = pixelformat;

  g_value_init (&list, GST_TYPE_LIST);

  /* step 1: get device default colorspace and insert it first as
   * it should be the preferred one */
  if (gst_v4l2_object_try_fmt (v4l2object, &fmt) == 0) {
    if (gst_v4l2_object_get_colorspace (&fmt, &cinfo))
      gst_v4l2_object_fill_colorimetry_list (&list, &cinfo);
  }

  /* step 2: probe all colorspace other than default
   * We don't probe all colorspace, range, matrix and transfer combination to
   * avoid ioctl flooding which could greatly increase initialization time
   * with low-speed devices (UVC...) */
  for (req_cspace = V4L2_COLORSPACE_SMPTE170M;
      req_cspace <= V4L2_COLORSPACE_RAW; req_cspace++) {
    /* V4L2_COLORSPACE_BT878 is deprecated and shall not be used, so skip */
    if (req_cspace == V4L2_COLORSPACE_BT878)
      continue;

    if (V4L2_TYPE_IS_MULTIPLANAR (v4l2object->type))
      fmt.fmt.pix_mp.colorspace = req_cspace;
    else
      fmt.fmt.pix.colorspace = req_cspace;

    if (gst_v4l2_object_try_fmt (v4l2object, &fmt) == 0) {
      enum v4l2_colorspace colorspace;

      if (V4L2_TYPE_IS_MULTIPLANAR (v4l2object->type))
        colorspace = fmt.fmt.pix_mp.colorspace;
      else
        colorspace = fmt.fmt.pix.colorspace;

      if (colorspace == req_cspace) {
        if (gst_v4l2_object_get_colorspace (&fmt, &cinfo))
          gst_v4l2_object_fill_colorimetry_list (&list, &cinfo);
      }
    }
  }

  if (gst_value_list_get_size (&list) > 0)
    gst_structure_take_value (s, "colorimetry", &list);
  else
    g_value_unset (&list);

  return;
}

/* The frame interval enumeration code first appeared in Linux 2.6.19. */
static GstStructure *
gst_v4l2_object_probe_caps_for_format_and_size (GstV4l2Object * v4l2object,
    guint32 pixelformat,
    guint32 width, guint32 height, const GstStructure * template)
{
  gint fd = v4l2object->video_fd;
  struct v4l2_frmivalenum ival;
  guint32 num, denom;
  GstStructure *s;
  GValue rates = { 0, };

  memset (&ival, 0, sizeof (struct v4l2_frmivalenum));
  ival.index = 0;
  ival.pixel_format = pixelformat;
  ival.width = width;
  ival.height = height;

  GST_LOG_OBJECT (v4l2object->dbg_obj,
      "get frame interval for %ux%u, %" GST_FOURCC_FORMAT, width, height,
      GST_FOURCC_ARGS (pixelformat));

  /* keep in mind that v4l2 gives us frame intervals (durations); we invert the
   * fraction to get framerate */
  if (v4l2object->ioctl (fd, VIDIOC_ENUM_FRAMEINTERVALS, &ival) < 0)
    goto enum_frameintervals_failed;

  if (ival.type == V4L2_FRMIVAL_TYPE_DISCRETE) {
    GValue rate = { 0, };

    g_value_init (&rates, GST_TYPE_LIST);
    g_value_init (&rate, GST_TYPE_FRACTION);

    do {
      num = ival.discrete.numerator;
      denom = ival.discrete.denominator;

      if (num > G_MAXINT || denom > G_MAXINT) {
        /* let us hope we don't get here... */
        num >>= 1;
        denom >>= 1;
      }

      GST_LOG_OBJECT (v4l2object->dbg_obj, "adding discrete framerate: %d/%d",
          denom, num);

      /* swap to get the framerate */
      gst_value_set_fraction (&rate, denom, num);
      gst_value_list_append_value (&rates, &rate);

      ival.index++;
    } while (v4l2object->ioctl (fd, VIDIOC_ENUM_FRAMEINTERVALS, &ival) >= 0);
  } else if (ival.type == V4L2_FRMIVAL_TYPE_STEPWISE) {
    GValue min = { 0, };
    GValue step = { 0, };
    GValue max = { 0, };
    gboolean added = FALSE;
    guint32 minnum, mindenom;
    guint32 maxnum, maxdenom;

    g_value_init (&rates, GST_TYPE_LIST);

    g_value_init (&min, GST_TYPE_FRACTION);
    g_value_init (&step, GST_TYPE_FRACTION);
    g_value_init (&max, GST_TYPE_FRACTION);

    /* get the min */
    minnum = ival.stepwise.min.numerator;
    mindenom = ival.stepwise.min.denominator;
    if (minnum > G_MAXINT || mindenom > G_MAXINT) {
      minnum >>= 1;
      mindenom >>= 1;
    }
    GST_LOG_OBJECT (v4l2object->dbg_obj, "stepwise min frame interval: %d/%d",
        minnum, mindenom);
    gst_value_set_fraction (&min, minnum, mindenom);

    /* get the max */
    maxnum = ival.stepwise.max.numerator;
    maxdenom = ival.stepwise.max.denominator;
    if (maxnum > G_MAXINT || maxdenom > G_MAXINT) {
      maxnum >>= 1;
      maxdenom >>= 1;
    }

    GST_LOG_OBJECT (v4l2object->dbg_obj, "stepwise max frame interval: %d/%d",
        maxnum, maxdenom);
    gst_value_set_fraction (&max, maxnum, maxdenom);

    /* get the step */
    num = ival.stepwise.step.numerator;
    denom = ival.stepwise.step.denominator;
    if (num > G_MAXINT || denom > G_MAXINT) {
      num >>= 1;
      denom >>= 1;
    }

    if (num == 0 || denom == 0) {
      /* in this case we have a wrong fraction or no step, set the step to max
       * so that we only add the min value in the loop below */
      num = maxnum;
      denom = maxdenom;
    }

    /* since we only have gst_value_fraction_subtract and not add, negate the
     * numerator */
    GST_LOG_OBJECT (v4l2object->dbg_obj, "stepwise step frame interval: %d/%d",
        num, denom);
    gst_value_set_fraction (&step, -num, denom);

    while (gst_value_compare (&min, &max) != GST_VALUE_GREATER_THAN) {
      GValue rate = { 0, };

      num = gst_value_get_fraction_numerator (&min);
      denom = gst_value_get_fraction_denominator (&min);
      GST_LOG_OBJECT (v4l2object->dbg_obj, "adding stepwise framerate: %d/%d",
          denom, num);

      /* invert to get the framerate */
      g_value_init (&rate, GST_TYPE_FRACTION);
      gst_value_set_fraction (&rate, denom, num);
      gst_value_list_append_value (&rates, &rate);
      added = TRUE;

      /* we're actually adding because step was negated above. This is because
       * there is no _add function... */
      if (!gst_value_fraction_subtract (&min, &min, &step)) {
        GST_WARNING_OBJECT (v4l2object->dbg_obj, "could not step fraction!");
        break;
      }
    }
    if (!added) {
      /* no range was added, leave the default range from the template */
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "no range added, leaving default");
      g_value_unset (&rates);
    }
  } else if (ival.type == V4L2_FRMIVAL_TYPE_CONTINUOUS) {
    guint32 maxnum, maxdenom;

    g_value_init (&rates, GST_TYPE_FRACTION_RANGE);

    num = ival.stepwise.min.numerator;
    denom = ival.stepwise.min.denominator;
    if (num > G_MAXINT || denom > G_MAXINT) {
      num >>= 1;
      denom >>= 1;
    }

    maxnum = ival.stepwise.max.numerator;
    maxdenom = ival.stepwise.max.denominator;
    if (maxnum > G_MAXINT || maxdenom > G_MAXINT) {
      maxnum >>= 1;
      maxdenom >>= 1;
    }

    GST_LOG_OBJECT (v4l2object->dbg_obj,
        "continuous frame interval %d/%d to %d/%d", maxdenom, maxnum, denom,
        num);

    gst_value_set_fraction_range_full (&rates, maxdenom, maxnum, denom, num);
  } else {
    goto unknown_type;
  }

return_data:
  s = gst_structure_copy (template);
  gst_structure_set (s, "width", G_TYPE_INT, (gint) width,
      "height", G_TYPE_INT, (gint) height, NULL);

  gst_v4l2_object_add_aspect_ratio (v4l2object, s);
  gst_v4l2_object_add_interlace_mode (v4l2object, s, width, height,
      pixelformat);

  if (!v4l2object->skip_try_fmt_probes) {
    gst_v4l2_object_add_colorspace (v4l2object, s, width, height, pixelformat);
  }

  if (G_IS_VALUE (&rates)) {
    gst_v4l2src_value_simplify (&rates);
    /* only change the framerate on the template when we have a valid probed new
     * value */
    gst_structure_take_value (s, "framerate", &rates);
  } else if (v4l2object->type == V4L2_BUF_TYPE_VIDEO_CAPTURE ||
      v4l2object->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
    gst_structure_set (s, "framerate", GST_TYPE_FRACTION_RANGE, 0, 1, G_MAXINT,
        1, NULL);
  }
  return s;

  /* ERRORS */
enum_frameintervals_failed:
  {
    GST_DEBUG_OBJECT (v4l2object->dbg_obj,
        "Unable to enumerate intervals for %" GST_FOURCC_FORMAT "@%ux%u",
        GST_FOURCC_ARGS (pixelformat), width, height);
    goto return_data;
  }
unknown_type:
  {
    /* I don't see how this is actually an error, we ignore the format then */
    GST_WARNING_OBJECT (v4l2object->dbg_obj,
        "Unknown frame interval type at %" GST_FOURCC_FORMAT "@%ux%u: %u",
        GST_FOURCC_ARGS (pixelformat), width, height, ival.type);
    return NULL;
  }
}

static gint
sort_by_frame_size (GstStructure * s1, GstStructure * s2)
{
  int w1, h1, w2, h2;

  gst_structure_get_int (s1, "width", &w1);
  gst_structure_get_int (s1, "height", &h1);
  gst_structure_get_int (s2, "width", &w2);
  gst_structure_get_int (s2, "height", &h2);

  /* I think it's safe to assume that this won't overflow for a while */
  return ((w2 * h2) - (w1 * h1));
}

static void
check_alternate_and_append_struct (GstCaps * caps, GstStructure * s)
{
  const GValue *mode;
  GstCapsFeatures *features = NULL;

  mode = gst_structure_get_value (s, "interlace-mode");
  if (!mode)
    goto done;

  if (G_VALUE_HOLDS_STRING (mode)) {
    /* Add the INTERLACED feature if the mode is alternate */
    if (!g_strcmp0 (gst_structure_get_string (s, "interlace-mode"),
            "alternate"))
      features =
          gst_caps_features_new (GST_CAPS_FEATURE_FORMAT_INTERLACED, NULL);
  } else if (GST_VALUE_HOLDS_LIST (mode)) {
    /* If the mode is a list containing alternate, remove it from the list and add a
     * variant with interlace-mode=alternate and the INTERLACED feature. */
    GValue alter = G_VALUE_INIT;
    GValue inter = G_VALUE_INIT;

    g_value_init (&alter, G_TYPE_STRING);
    g_value_set_string (&alter, "alternate");

    /* Cannot use gst_value_can_intersect() as it requires args to have the
     * same type. */
    if (gst_value_intersect (&inter, mode, &alter)) {
      GValue minus_alter = G_VALUE_INIT;
      GstStructure *copy;

      gst_value_subtract (&minus_alter, mode, &alter);
      gst_structure_take_value (s, "interlace-mode", &minus_alter);

      copy = gst_structure_copy (s);
      gst_structure_take_value (copy, "interlace-mode", &inter);
      gst_caps_append_structure_full (caps, copy,
          gst_caps_features_new (GST_CAPS_FEATURE_FORMAT_INTERLACED, NULL));
    }
    g_value_unset (&alter);
  }

done:
  gst_caps_append_structure_full (caps, s, features);
}

static void
dup_struct_with_xlnx_ll (GstCaps * caps, GstStructure * s)
{
  GstStructure *copy;

  copy = gst_structure_copy (s);
  gst_caps_append_structure_full (caps, copy,
      gst_caps_features_new (GST_CAPS_FEATURE_MEMORY_XLNX_LL, NULL));
}

static void
gst_v4l2_object_update_and_append (GstV4l2Object * v4l2object,
    guint32 format, GstCaps * caps, GstStructure * s)
{
  GstStructure *alt_s = NULL;

  /* Encoded stream on output buffer need to be parsed */
  if (v4l2object->type == V4L2_BUF_TYPE_VIDEO_OUTPUT ||
      v4l2object->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
    gint i = 0;

    for (; i < GST_V4L2_FORMAT_COUNT; i++) {
      if (format == gst_v4l2_formats[i].format &&
          gst_v4l2_formats[i].flags & GST_V4L2_CODEC &&
          !(gst_v4l2_formats[i].flags & GST_V4L2_NO_PARSE)) {
        gst_structure_set (s, "parsed", G_TYPE_BOOLEAN, TRUE, NULL);
        break;
      }
    }
  }

  if (v4l2object->has_alpha_component &&
      (v4l2object->type == V4L2_BUF_TYPE_VIDEO_CAPTURE ||
          v4l2object->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)) {
    switch (format) {
      case V4L2_PIX_FMT_RGB32:
        alt_s = gst_structure_copy (s);
        gst_structure_set (alt_s, "format", G_TYPE_STRING, "ARGB", NULL);
        break;
      case V4L2_PIX_FMT_BGR32:
        alt_s = gst_structure_copy (s);
        gst_structure_set (alt_s, "format", G_TYPE_STRING, "BGRA", NULL);
        break;
      default:
        break;
    }
  }

  check_alternate_and_append_struct (caps, s);

  if (alt_s) {
    check_alternate_and_append_struct (caps, alt_s);
  }

  if ((v4l2object->type == V4L2_BUF_TYPE_VIDEO_CAPTURE
          || v4l2object->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
      && xlnx_ll_supported ()) {
    dup_struct_with_xlnx_ll (caps, s);
    if (alt_s) {
      dup_struct_with_xlnx_ll (caps, alt_s);
    }
  }
}

static GstCaps *
gst_v4l2_object_probe_caps_for_format (GstV4l2Object * v4l2object,
    guint32 pixelformat, const GstStructure * template)
{
  GstCaps *ret = gst_caps_new_empty ();
  GstStructure *tmp;
  gint fd = v4l2object->video_fd;
  struct v4l2_frmsizeenum size;
  GList *results = NULL;
  guint32 w, h;

  if (pixelformat == GST_MAKE_FOURCC ('M', 'P', 'E', 'G')) {
    gst_caps_append_structure (ret, gst_structure_copy (template));
    return ret;
  }

  memset (&size, 0, sizeof (struct v4l2_frmsizeenum));
  size.index = 0;
  size.pixel_format = pixelformat;

  GST_DEBUG_OBJECT (v4l2object->dbg_obj,
      "Enumerating frame sizes for %" GST_FOURCC_FORMAT,
      GST_FOURCC_ARGS (pixelformat));

  if (v4l2object->ioctl (fd, VIDIOC_ENUM_FRAMESIZES, &size) < 0)
    goto enum_framesizes_failed;

  if (size.type == V4L2_FRMSIZE_TYPE_DISCRETE) {
    do {
      GST_LOG_OBJECT (v4l2object->dbg_obj, "got discrete frame size %dx%d",
          size.discrete.width, size.discrete.height);

      w = MIN (size.discrete.width, G_MAXINT);
      h = MIN (size.discrete.height, G_MAXINT);

      if (w && h) {
        tmp =
            gst_v4l2_object_probe_caps_for_format_and_size (v4l2object,
            pixelformat, w, h, template);

        if (tmp)
          results = g_list_prepend (results, tmp);
      }

      size.index++;
    } while (v4l2object->ioctl (fd, VIDIOC_ENUM_FRAMESIZES, &size) >= 0);
    GST_DEBUG_OBJECT (v4l2object->dbg_obj,
        "done iterating discrete frame sizes");
  } else if (size.type == V4L2_FRMSIZE_TYPE_STEPWISE) {
    guint32 maxw, maxh, step_w, step_h;

    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "we have stepwise frame sizes:");
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "min width:   %d",
        size.stepwise.min_width);
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "min height:  %d",
        size.stepwise.min_height);
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "max width:   %d",
        size.stepwise.max_width);
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "min height:  %d",
        size.stepwise.max_height);
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "step width:  %d",
        size.stepwise.step_width);
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "step height: %d",
        size.stepwise.step_height);

    w = MAX (size.stepwise.min_width, 1);
    h = MAX (size.stepwise.min_height, 1);
    maxw = MIN (size.stepwise.max_width, G_MAXINT);
    maxh = MIN (size.stepwise.max_height, G_MAXINT);

    step_w = MAX (size.stepwise.step_width, 1);
    step_h = MAX (size.stepwise.step_height, 1);

    /* FIXME: check for sanity and that min/max are multiples of the steps */

    /* we only query details for the max width/height since it's likely the
     * most restricted if there are any resolution-dependent restrictions */
    tmp = gst_v4l2_object_probe_caps_for_format_and_size (v4l2object,
        pixelformat, maxw, maxh, template);

    if (tmp) {
      GValue step_range = G_VALUE_INIT;

      g_value_init (&step_range, GST_TYPE_INT_RANGE);
      gst_value_set_int_range_step (&step_range, w, maxw, step_w);
      gst_structure_set_value (tmp, "width", &step_range);

      gst_value_set_int_range_step (&step_range, h, maxh, step_h);
      gst_structure_take_value (tmp, "height", &step_range);

      /* no point using the results list here, since there's only one struct */
      gst_v4l2_object_update_and_append (v4l2object, pixelformat, ret, tmp);
    }
  } else if (size.type == V4L2_FRMSIZE_TYPE_CONTINUOUS) {
    guint32 maxw, maxh;

    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "we have continuous frame sizes:");
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "min width:   %d",
        size.stepwise.min_width);
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "min height:  %d",
        size.stepwise.min_height);
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "max width:   %d",
        size.stepwise.max_width);
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "min height:  %d",
        size.stepwise.max_height);

    w = MAX (size.stepwise.min_width, 1);
    h = MAX (size.stepwise.min_height, 1);
    maxw = MIN (size.stepwise.max_width, G_MAXINT);
    maxh = MIN (size.stepwise.max_height, G_MAXINT);

    tmp =
        gst_v4l2_object_probe_caps_for_format_and_size (v4l2object, pixelformat,
        w, h, template);
    if (tmp) {
      gst_structure_set (tmp, "width", GST_TYPE_INT_RANGE, (gint) w,
          (gint) maxw, "height", GST_TYPE_INT_RANGE, (gint) h, (gint) maxh,
          NULL);

      /* no point using the results list here, since there's only one struct */
      gst_v4l2_object_update_and_append (v4l2object, pixelformat, ret, tmp);
    }
  } else {
    goto unknown_type;
  }

  /* we use an intermediary list to store and then sort the results of the
   * probing because we can't make any assumptions about the order in which
   * the driver will give us the sizes, but we want the final caps to contain
   * the results starting with the highest resolution and having the lowest
   * resolution last, since order in caps matters for things like fixation. */
  results = g_list_sort (results, (GCompareFunc) sort_by_frame_size);
  while (results != NULL) {
    gst_v4l2_object_update_and_append (v4l2object, pixelformat, ret,
        results->data);
    results = g_list_delete_link (results, results);
  }

  if (gst_caps_is_empty (ret))
    goto enum_framesizes_no_results;

  return ret;

  /* ERRORS */
enum_framesizes_failed:
  {
    /* I don't see how this is actually an error */
    GST_DEBUG_OBJECT (v4l2object->dbg_obj,
        "Failed to enumerate frame sizes for pixelformat %" GST_FOURCC_FORMAT
        " (%s)", GST_FOURCC_ARGS (pixelformat), g_strerror (errno));
    goto default_frame_sizes;
  }
enum_framesizes_no_results:
  {
    /* it's possible that VIDIOC_ENUM_FRAMESIZES is defined but the driver in
     * question doesn't actually support it yet */
    GST_DEBUG_OBJECT (v4l2object->dbg_obj,
        "No results for pixelformat %" GST_FOURCC_FORMAT
        " enumerating frame sizes, trying fallback",
        GST_FOURCC_ARGS (pixelformat));
    goto default_frame_sizes;
  }
unknown_type:
  {
    GST_WARNING_OBJECT (v4l2object->dbg_obj,
        "Unknown frame sizeenum type for pixelformat %" GST_FOURCC_FORMAT
        ": %u", GST_FOURCC_ARGS (pixelformat), size.type);
    goto default_frame_sizes;
  }

default_frame_sizes:
  {
    gint min_w, max_w, min_h, max_h, fix_num = 0, fix_denom = 0;

    /* This code is for Linux < 2.6.19 */
    min_w = min_h = 1;
    max_w = max_h = GST_V4L2_MAX_SIZE;
    if (!gst_v4l2_object_get_nearest_size (v4l2object, pixelformat, &min_w,
            &min_h)) {
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "Could not probe minimum capture size for pixelformat %"
          GST_FOURCC_FORMAT, GST_FOURCC_ARGS (pixelformat));
    }
    if (!gst_v4l2_object_get_nearest_size (v4l2object, pixelformat, &max_w,
            &max_h)) {
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "Could not probe maximum capture size for pixelformat %"
          GST_FOURCC_FORMAT, GST_FOURCC_ARGS (pixelformat));
    }

    /* Since we can't get framerate directly, try to use the current norm */
    if (v4l2object->tv_norm && v4l2object->norms) {
      GList *norms;
      GstTunerNorm *norm = NULL;
      GstTunerNorm *current =
          gst_v4l2_tuner_get_norm_by_std_id (v4l2object, v4l2object->tv_norm);

      for (norms = v4l2object->norms; norms != NULL; norms = norms->next) {
        norm = (GstTunerNorm *) norms->data;
        if (!strcmp (norm->label, current->label))
          break;
      }
      /* If it's possible, set framerate to that (discrete) value */
      if (norm) {
        fix_num = gst_value_get_fraction_numerator (&norm->framerate);
        fix_denom = gst_value_get_fraction_denominator (&norm->framerate);
      }
    }

    tmp = gst_structure_copy (template);
    if (fix_num) {
      gst_structure_set (tmp, "framerate", GST_TYPE_FRACTION, fix_num,
          fix_denom, NULL);
    } else if (v4l2object->type == V4L2_BUF_TYPE_VIDEO_CAPTURE ||
        v4l2object->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
      /* if norm can't be used, copy the template framerate */
      gst_structure_set (tmp, "framerate", GST_TYPE_FRACTION_RANGE, 0, 1,
          G_MAXINT, 1, NULL);
    }

    if (min_w == max_w)
      gst_structure_set (tmp, "width", G_TYPE_INT, max_w, NULL);
    else
      gst_structure_set (tmp, "width", GST_TYPE_INT_RANGE, min_w, max_w, NULL);

    if (min_h == max_h)
      gst_structure_set (tmp, "height", G_TYPE_INT, max_h, NULL);
    else
      gst_structure_set (tmp, "height", GST_TYPE_INT_RANGE, min_h, max_h, NULL);

    gst_v4l2_object_add_aspect_ratio (v4l2object, tmp);

    /* We could consider setting interlace mode from min and max. */
    gst_v4l2_object_add_interlace_mode (v4l2object, tmp, max_w, max_h,
        pixelformat);

    if (!v4l2object->skip_try_fmt_probes) {
      /* We could consider to check colorspace for min too, in case it depends on
       * the size. But in this case, min and max could not be enough */
      gst_v4l2_object_add_colorspace (v4l2object, tmp, max_w, max_h,
          pixelformat);
    }

    gst_v4l2_object_update_and_append (v4l2object, pixelformat, ret, tmp);
    return ret;
  }
}

static gboolean
gst_v4l2_object_get_nearest_size (GstV4l2Object * v4l2object,
    guint32 pixelformat, gint * width, gint * height)
{
  struct v4l2_format fmt;
  gboolean ret = FALSE;
  GstVideoInterlaceMode interlace_mode;

  g_return_val_if_fail (width != NULL, FALSE);
  g_return_val_if_fail (height != NULL, FALSE);

  GST_LOG_OBJECT (v4l2object->dbg_obj,
      "getting nearest size to %dx%d with format %" GST_FOURCC_FORMAT,
      *width, *height, GST_FOURCC_ARGS (pixelformat));

  memset (&fmt, 0, sizeof (struct v4l2_format));

  /* get size delimiters */
  memset (&fmt, 0, sizeof (fmt));
  fmt.type = v4l2object->type;
  fmt.fmt.pix.width = *width;
  fmt.fmt.pix.height = *height;
  fmt.fmt.pix.pixelformat = pixelformat;
  fmt.fmt.pix.field = V4L2_FIELD_ANY;

  if (gst_v4l2_object_try_fmt (v4l2object, &fmt) < 0)
    goto error;

  GST_LOG_OBJECT (v4l2object->dbg_obj,
      "got nearest size %dx%d", fmt.fmt.pix.width, fmt.fmt.pix.height);

  *width = fmt.fmt.pix.width;
  *height = fmt.fmt.pix.height;

  if (!gst_v4l2_object_get_interlace_mode (fmt.fmt.pix.field, &interlace_mode)) {
    GST_WARNING_OBJECT (v4l2object->dbg_obj,
        "Unsupported field type for %" GST_FOURCC_FORMAT "@%ux%u: %u",
        GST_FOURCC_ARGS (pixelformat), *width, *height, fmt.fmt.pix.field);
    goto error;
  }

  ret = TRUE;

error:
  if (!ret) {
    GST_WARNING_OBJECT (v4l2object->dbg_obj,
        "Unable to try format: %s", g_strerror (errno));
  }

  return ret;
}

static gboolean
gst_v4l2_object_is_dmabuf_supported (GstV4l2Object * v4l2object)
{
  gboolean ret = TRUE;
  struct v4l2_exportbuffer expbuf = {
    .type = v4l2object->type,
    .index = -1,
    .plane = -1,
    .flags = O_CLOEXEC | O_RDWR,
  };

  if (v4l2object->fmtdesc->flags & V4L2_FMT_FLAG_EMULATED) {
    GST_WARNING_OBJECT (v4l2object->dbg_obj,
        "libv4l2 converter detected, disabling DMABuf");
    ret = FALSE;
  }

  /* Expected to fail, but ENOTTY tells us that it is not implemented. */
  v4l2object->ioctl (v4l2object->video_fd, VIDIOC_EXPBUF, &expbuf);
  if (errno == ENOTTY)
    ret = FALSE;

  return ret;
}

static gboolean
gst_v4l2_object_setup_pool (GstV4l2Object * v4l2object, GstCaps * caps)
{
  GstV4l2IOMode mode;

  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "initializing the %s system",
      V4L2_TYPE_IS_OUTPUT (v4l2object->type) ? "output" : "capture");

  GST_V4L2_CHECK_OPEN (v4l2object);
  GST_V4L2_CHECK_NOT_ACTIVE (v4l2object);

  /* find transport */
  mode = v4l2object->req_mode;

  if (v4l2object->device_caps & V4L2_CAP_READWRITE) {
    if (v4l2object->req_mode == GST_V4L2_IO_AUTO)
      mode = GST_V4L2_IO_RW;
  } else if (v4l2object->req_mode == GST_V4L2_IO_RW)
    goto method_not_supported;

  if (v4l2object->device_caps & V4L2_CAP_STREAMING) {
    if (v4l2object->req_mode == GST_V4L2_IO_AUTO) {
      if (!V4L2_TYPE_IS_OUTPUT (v4l2object->type) &&
          gst_v4l2_object_is_dmabuf_supported (v4l2object)) {
        mode = GST_V4L2_IO_DMABUF;
      } else {
        mode = GST_V4L2_IO_MMAP;
      }
    }
  } else if (v4l2object->req_mode == GST_V4L2_IO_MMAP ||
      v4l2object->req_mode == GST_V4L2_IO_DMABUF)
    goto method_not_supported;

  /* if still no transport selected, error out */
  if (mode == GST_V4L2_IO_AUTO)
    goto no_supported_capture_method;

  GST_INFO_OBJECT (v4l2object->dbg_obj, "accessing buffers via mode %d", mode);
  v4l2object->mode = mode;

  /* If min_buffers is not set, the driver either does not support the control or
     it has not been asked yet via propose_allocation/decide_allocation. */
  if (!v4l2object->min_buffers)
    gst_v4l2_get_driver_min_buffers (v4l2object);

  /* Map the buffers */
  GST_LOG_OBJECT (v4l2object->dbg_obj, "initiating buffer pool");

  if (!(v4l2object->pool = gst_v4l2_buffer_pool_new (v4l2object, caps)))
    goto buffer_pool_new_failed;

  GST_V4L2_SET_ACTIVE (v4l2object);

  return TRUE;

  /* ERRORS */
buffer_pool_new_failed:
  {
    GST_ELEMENT_ERROR (v4l2object->element, RESOURCE, READ,
        (_("Could not map buffers from device '%s'"),
            v4l2object->videodev),
        ("Failed to create buffer pool: %s", g_strerror (errno)));
    return FALSE;
  }
method_not_supported:
  {
    GST_ELEMENT_ERROR (v4l2object->element, RESOURCE, READ,
        (_("The driver of device '%s' does not support the IO method %d"),
            v4l2object->videodev, mode), (NULL));
    return FALSE;
  }
no_supported_capture_method:
  {
    GST_ELEMENT_ERROR (v4l2object->element, RESOURCE, READ,
        (_("The driver of device '%s' does not support any known IO "
                "method."), v4l2object->videodev), (NULL));
    return FALSE;
  }
}

static void
gst_v4l2_object_set_stride (GstVideoInfo * info, GstVideoAlignment * align,
    gint plane, gint stride)
{
  const GstVideoFormatInfo *finfo = info->finfo;

  if (GST_VIDEO_FORMAT_INFO_IS_TILED (finfo)) {
    gint x_tiles, y_tiles, ws, hs, tile_height, padded_height;


    ws = GST_VIDEO_FORMAT_INFO_TILE_WS (finfo);
    hs = GST_VIDEO_FORMAT_INFO_TILE_HS (finfo);
    tile_height = 1 << hs;

    padded_height = GST_VIDEO_FORMAT_INFO_SCALE_HEIGHT (finfo, plane,
        info->height + align->padding_top + align->padding_bottom);
    padded_height = GST_ROUND_UP_N (padded_height, tile_height);

    x_tiles = stride >> ws;
    y_tiles = padded_height >> hs;
    info->stride[plane] = GST_VIDEO_TILE_MAKE_STRIDE (x_tiles, y_tiles);
  } else {
    info->stride[plane] = stride;
  }
}

static void
gst_v4l2_object_extrapolate_info (GstV4l2Object * v4l2object,
    GstVideoInfo * info, GstVideoAlignment * align, gint stride)
{
  const GstVideoFormatInfo *finfo = info->finfo;
  gint i, estride, padded_height;
  gsize offs = 0;

  g_return_if_fail (v4l2object->n_v4l2_planes == 1);

  padded_height =
      GST_VIDEO_INFO_FIELD_HEIGHT (info) + align->padding_top +
      align->padding_bottom;

  for (i = 0; i < finfo->n_planes; i++) {
    estride = gst_v4l2_object_extrapolate_stride (finfo, i, stride);

    gst_v4l2_object_set_stride (info, align, i, estride);

    info->offset[i] = offs;
    offs += estride *
        GST_VIDEO_FORMAT_INFO_SCALE_HEIGHT (finfo, i, padded_height);

    GST_DEBUG_OBJECT (v4l2object->dbg_obj,
        "Extrapolated for plane %d with base stride %d: "
        "stride %d, offset %" G_GSIZE_FORMAT, i, stride, info->stride[i],
        info->offset[i]);
  }

  /* Update the image size according the amount of data we are going to
   * read/write. This workaround bugs in driver where the sizeimage provided
   * by TRY/S_FMT represent the buffer length (maximum size) rather then the expected
   * bytesused (buffer size). */
  if (offs < info->size)
    info->size = offs;
}

static void
gst_v4l2_object_save_format (GstV4l2Object * v4l2object,
    struct v4l2_fmtdesc *fmtdesc, struct v4l2_format *format,
    GstVideoInfo * info, GstVideoAlignment * align)
{
  const GstVideoFormatInfo *finfo = info->finfo;
  gboolean standard_stride = TRUE;
  gint stride, pstride, padded_width, padded_height, i;

  if (GST_VIDEO_INFO_FORMAT (info) == GST_VIDEO_FORMAT_ENCODED) {
    v4l2object->n_v4l2_planes = 1;
    info->size = format->fmt.pix.sizeimage;
    goto store_info;
  }

  /* adjust right padding */
  if (V4L2_TYPE_IS_MULTIPLANAR (v4l2object->type))
    stride = format->fmt.pix_mp.plane_fmt[0].bytesperline;
  else
    stride = format->fmt.pix.bytesperline;

  pstride = GST_VIDEO_FORMAT_INFO_PSTRIDE (finfo, 0);
  if (pstride) {
    padded_width = stride / pstride;
  } else {
    /* pstride can be 0 for complex formats */
    GST_WARNING_OBJECT (v4l2object->element,
        "format %s has a pstride of 0, cannot compute padded with",
        gst_video_format_to_string (GST_VIDEO_INFO_FORMAT (info)));
    padded_width = stride;
  }

  if (padded_width < format->fmt.pix.width)
    GST_WARNING_OBJECT (v4l2object->dbg_obj,
        "Driver bug detected, stride (%d) is too small for the width (%d)",
        padded_width, format->fmt.pix.width);

  align->padding_right = padded_width - info->width - align->padding_left;

  /* adjust bottom padding */
  padded_height = format->fmt.pix.height;

  if (GST_VIDEO_FORMAT_INFO_IS_TILED (finfo)) {
    guint hs, tile_height;

    hs = GST_VIDEO_FORMAT_INFO_TILE_HS (finfo);
    tile_height = 1 << hs;

    padded_height = GST_ROUND_UP_N (padded_height, tile_height);
  }

  align->padding_bottom =
      padded_height - GST_VIDEO_INFO_FIELD_HEIGHT (info) - align->padding_top;

  /* setup the strides and offset */
  if (V4L2_TYPE_IS_MULTIPLANAR (v4l2object->type)) {
    struct v4l2_pix_format_mplane *pix_mp = &format->fmt.pix_mp;

    /* figure out the frame layout */
    v4l2object->n_v4l2_planes = MAX (1, pix_mp->num_planes);
    info->size = 0;
    for (i = 0; i < v4l2object->n_v4l2_planes; i++) {
      stride = pix_mp->plane_fmt[i].bytesperline;

      if (info->stride[i] != stride)
        standard_stride = FALSE;

      gst_v4l2_object_set_stride (info, align, i, stride);
      info->offset[i] = info->size;
      info->size += pix_mp->plane_fmt[i].sizeimage;
    }

    /* Extrapolate stride if planar format are being set in 1 v4l2 plane */
    if (v4l2object->n_v4l2_planes < finfo->n_planes) {
      stride = format->fmt.pix_mp.plane_fmt[0].bytesperline;
      gst_v4l2_object_extrapolate_info (v4l2object, info, align, stride);
    }
  } else {
    /* only one plane in non-MPLANE mode */
    v4l2object->n_v4l2_planes = 1;
    info->size = format->fmt.pix.sizeimage;
    stride = format->fmt.pix.bytesperline;

    if (info->stride[0] != stride)
      standard_stride = FALSE;

    gst_v4l2_object_extrapolate_info (v4l2object, info, align, stride);
  }

  /* adjust the offset to take into account left and top */
  if (GST_VIDEO_FORMAT_INFO_IS_TILED (finfo)) {
    if ((align->padding_left + align->padding_top) > 0)
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "Left and top padding is not permitted for tiled formats");
  } else {
    for (i = 0; i < finfo->n_planes; i++) {
      gint vedge, hedge;

      /* FIXME we assume plane as component as this is true for all supported
       * format we support. */

      hedge = GST_VIDEO_FORMAT_INFO_SCALE_WIDTH (finfo, i, align->padding_left);
      vedge = GST_VIDEO_FORMAT_INFO_SCALE_HEIGHT (finfo, i, align->padding_top);

      info->offset[i] += (vedge * info->stride[i]) +
          (hedge * GST_VIDEO_INFO_COMP_PSTRIDE (info, i));
    }
  }

store_info:
  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "Got sizeimage %" G_GSIZE_FORMAT,
      info->size);

  /* to avoid copies we need video meta if there is padding */
  v4l2object->need_video_meta =
      ((align->padding_top + align->padding_left + align->padding_right +
          align->padding_bottom) != 0);

  /* ... or if stride is non "standard" */
  if (!standard_stride)
    v4l2object->need_video_meta = TRUE;

  /* ... or also video meta if we use multiple, non-contiguous, planes */
  if (v4l2object->n_v4l2_planes > 1)
    v4l2object->need_video_meta = TRUE;

  v4l2object->info = *info;
  v4l2object->align = *align;
  v4l2object->format = *format;
  v4l2object->fmtdesc = fmtdesc;

  /* if we have a framerate pre-calculate duration */
  if (info->fps_n > 0 && info->fps_d > 0) {
    v4l2object->duration = gst_util_uint64_scale_int (GST_SECOND, info->fps_d,
        info->fps_n);
    if (GST_VIDEO_INFO_INTERLACE_MODE (info) ==
        GST_VIDEO_INTERLACE_MODE_ALTERNATE)
      v4l2object->duration /= 2;
  } else {
    v4l2object->duration = GST_CLOCK_TIME_NONE;
  }
}

gint
gst_v4l2_object_extrapolate_stride (const GstVideoFormatInfo * finfo,
    gint plane, gint stride)
{
  gint estride;

  switch (finfo->format) {
    case GST_VIDEO_FORMAT_NV12:
    case GST_VIDEO_FORMAT_NV12_64Z32:
    case GST_VIDEO_FORMAT_NV21:
    case GST_VIDEO_FORMAT_NV16:
    case GST_VIDEO_FORMAT_NV61:
    case GST_VIDEO_FORMAT_NV24:
    case GST_VIDEO_FORMAT_NV12_10LE32:
    case GST_VIDEO_FORMAT_NV16_10LE32:
      estride = (plane == 0 ? 1 : 2) *
          GST_VIDEO_FORMAT_INFO_SCALE_WIDTH (finfo, plane, stride);
      break;
    default:
      estride = GST_VIDEO_FORMAT_INFO_SCALE_WIDTH (finfo, plane, stride);
      break;
  }

  return estride;
}

static enum v4l2_field
get_v4l2_field_for_info (GstVideoInfo * info)
{
  if (!GST_VIDEO_INFO_IS_INTERLACED (info))
    return V4L2_FIELD_NONE;

  if (GST_VIDEO_INFO_INTERLACE_MODE (info) ==
      GST_VIDEO_INTERLACE_MODE_ALTERNATE)
    return V4L2_FIELD_ALTERNATE;

  switch (GST_VIDEO_INFO_FIELD_ORDER (info)) {
    case GST_VIDEO_FIELD_ORDER_TOP_FIELD_FIRST:
      return V4L2_FIELD_INTERLACED_TB;
    case GST_VIDEO_FIELD_ORDER_BOTTOM_FIELD_FIRST:
      return V4L2_FIELD_INTERLACED_BT;
    case GST_VIDEO_FIELD_ORDER_UNKNOWN:
    default:
      return V4L2_FIELD_INTERLACED;
  }
}

static gboolean
gst_v4l2_video_colorimetry_matches (const GstVideoColorimetry * cinfo,
    const gchar * color)
{
  GstVideoColorimetry ci;
  static const GstVideoColorimetry ci_likely_jpeg = {
    GST_VIDEO_COLOR_RANGE_0_255, GST_VIDEO_COLOR_MATRIX_BT601,
    GST_VIDEO_TRANSFER_UNKNOWN, GST_VIDEO_COLOR_PRIMARIES_UNKNOWN
  };
  static const GstVideoColorimetry ci_jpeg = {
    GST_VIDEO_COLOR_RANGE_0_255, GST_VIDEO_COLOR_MATRIX_BT601,
    GST_VIDEO_TRANSFER_SRGB, GST_VIDEO_COLOR_PRIMARIES_BT709
  };

  if (!gst_video_colorimetry_from_string (&ci, color))
    return FALSE;

  if (gst_video_colorimetry_is_equal (&ci, cinfo))
    return TRUE;

  /* Allow 1:4:0:0 (produced by jpegdec) if the device expects 1:4:7:1 */
  if (gst_video_colorimetry_is_equal (&ci, &ci_likely_jpeg)
      && gst_video_colorimetry_is_equal (cinfo, &ci_jpeg))
    return TRUE;

  return FALSE;
}

static gboolean
gst_v4l2_object_set_format_full (GstV4l2Object * v4l2object, GstCaps * caps,
    gboolean try_only, GstV4l2Error * error)
{
  gint fd = v4l2object->video_fd;
  struct v4l2_format format;
  struct v4l2_streamparm streamparm;
  enum v4l2_field field;
  guint32 pixelformat;
  struct v4l2_fmtdesc *fmtdesc;
  GstVideoInfo info;
  GstVideoAlignment align;
  gint width, height, fps_n, fps_d;
  gint n_v4l_planes;
  gint i = 0;
  gboolean is_mplane;
  enum v4l2_colorspace colorspace = 0;
  enum v4l2_quantization range = 0;
  enum v4l2_ycbcr_encoding matrix = 0;
  enum v4l2_xfer_func transfer = 0;
  GstStructure *s;
  GstCapsFeatures *features;
  gboolean disable_colorimetry = FALSE;

  g_return_val_if_fail (!v4l2object->skip_try_fmt_probes ||
      gst_caps_is_writable (caps), FALSE);

  GST_V4L2_CHECK_OPEN (v4l2object);
  if (!try_only)
    GST_V4L2_CHECK_NOT_ACTIVE (v4l2object);

  is_mplane = V4L2_TYPE_IS_MULTIPLANAR (v4l2object->type);

  gst_video_info_init (&info);
  gst_video_alignment_reset (&align);

  if (!gst_v4l2_object_get_caps_info (v4l2object, caps, &fmtdesc, &info))
    goto invalid_caps;

  pixelformat = fmtdesc->pixelformat;
  width = GST_VIDEO_INFO_WIDTH (&info);
  height = GST_VIDEO_INFO_FIELD_HEIGHT (&info);
  fps_n = GST_VIDEO_INFO_FPS_N (&info);
  fps_d = GST_VIDEO_INFO_FPS_D (&info);

  if (v4l2object->force_ntsc_tv && height == 240) {
    height = 243;
    width = 720;
    GST_LOG_OBJECT (v4l2object->dbg_obj,
        "Forcing format to TV D1 NTSC (720x486i)");
  }

  /* if encoded format (GST_VIDEO_INFO_N_PLANES return 0)
   * or if contiguous is prefered */
  n_v4l_planes = GST_VIDEO_INFO_N_PLANES (&info);
  if (!n_v4l_planes || !v4l2object->prefered_non_contiguous)
    n_v4l_planes = 1;

  field = get_v4l2_field_for_info (&info);
  if (field != V4L2_FIELD_NONE)
    GST_DEBUG_OBJECT (v4l2object->element, "interlaced video");
  else
    GST_DEBUG_OBJECT (v4l2object->element, "progressive video");

  /* We first pick the main colorspace from the primaries */
  switch (info.colorimetry.primaries) {
    case GST_VIDEO_COLOR_PRIMARIES_BT709:
      /* There is two colorspaces using these primaries, use the range to
       * differentiate */
      if (info.colorimetry.range == GST_VIDEO_COLOR_RANGE_16_235)
        colorspace = V4L2_COLORSPACE_REC709;
      else
        colorspace = V4L2_COLORSPACE_SRGB;
      break;
    case GST_VIDEO_COLOR_PRIMARIES_BT2020:
      colorspace = V4L2_COLORSPACE_BT2020;
      break;
    case GST_VIDEO_COLOR_PRIMARIES_BT470M:
      colorspace = V4L2_COLORSPACE_470_SYSTEM_M;
      break;
    case GST_VIDEO_COLOR_PRIMARIES_BT470BG:
      colorspace = V4L2_COLORSPACE_470_SYSTEM_BG;
      break;
    case GST_VIDEO_COLOR_PRIMARIES_SMPTE170M:
      colorspace = V4L2_COLORSPACE_SMPTE170M;
      break;
    case GST_VIDEO_COLOR_PRIMARIES_SMPTE240M:
      colorspace = V4L2_COLORSPACE_SMPTE240M;
      break;

    case GST_VIDEO_COLOR_PRIMARIES_FILM:
    case GST_VIDEO_COLOR_PRIMARIES_UNKNOWN:
      /* We don't know, we will guess */
      break;

    default:
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "Unknown colorimetry primaries %d", info.colorimetry.primaries);
      break;
  }

  switch (info.colorimetry.range) {
    case GST_VIDEO_COLOR_RANGE_0_255:
      range = V4L2_QUANTIZATION_FULL_RANGE;
      break;
    case GST_VIDEO_COLOR_RANGE_16_235:
      range = V4L2_QUANTIZATION_LIM_RANGE;
      break;
    case GST_VIDEO_COLOR_RANGE_UNKNOWN:
      /* We let the driver pick a default one */
      break;
    default:
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "Unknown colorimetry range %d", info.colorimetry.range);
      break;
  }

  switch (info.colorimetry.matrix) {
    case GST_VIDEO_COLOR_MATRIX_RGB:
      /* Unspecified, leave to default */
      break;
      /* FCC is about the same as BT601 with less digit */
    case GST_VIDEO_COLOR_MATRIX_FCC:
    case GST_VIDEO_COLOR_MATRIX_BT601:
      matrix = V4L2_YCBCR_ENC_601;
      break;
    case GST_VIDEO_COLOR_MATRIX_BT709:
      matrix = V4L2_YCBCR_ENC_709;
      break;
    case GST_VIDEO_COLOR_MATRIX_SMPTE240M:
      matrix = V4L2_YCBCR_ENC_SMPTE240M;
      break;
    case GST_VIDEO_COLOR_MATRIX_BT2020:
      matrix = V4L2_YCBCR_ENC_BT2020;
      break;
    case GST_VIDEO_COLOR_MATRIX_UNKNOWN:
      /* We let the driver pick a default one */
      break;
    default:
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "Unknown colorimetry matrix %d", info.colorimetry.matrix);
      break;
  }

  switch (info.colorimetry.transfer) {
    case GST_VIDEO_TRANSFER_GAMMA18:
    case GST_VIDEO_TRANSFER_GAMMA20:
    case GST_VIDEO_TRANSFER_GAMMA22:
    case GST_VIDEO_TRANSFER_GAMMA28:
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "GAMMA 18, 20, 22, 28 transfer functions not supported");
      /* fallthrough */
    case GST_VIDEO_TRANSFER_GAMMA10:
      transfer = V4L2_XFER_FUNC_NONE;
      break;
    case GST_VIDEO_TRANSFER_BT2020_12:
    case GST_VIDEO_TRANSFER_BT709:
      transfer = V4L2_XFER_FUNC_709;
      break;
    case GST_VIDEO_TRANSFER_SMPTE240M:
      transfer = V4L2_XFER_FUNC_SMPTE240M;
      break;
    case GST_VIDEO_TRANSFER_SRGB:
      transfer = V4L2_XFER_FUNC_SRGB;
      break;
    case GST_VIDEO_TRANSFER_LOG100:
    case GST_VIDEO_TRANSFER_LOG316:
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "LOG 100, 316 transfer functions not supported");
      /* FIXME No known sensible default, maybe AdobeRGB ? */
      break;
    case GST_VIDEO_TRANSFER_UNKNOWN:
      /* We let the driver pick a default one */
      break;
    default:
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "Unknown colorimetry tranfer %d", info.colorimetry.transfer);
      break;
  }

  if (colorspace == 0) {
    /* Try to guess colorspace according to pixelformat and size */
    if (GST_VIDEO_INFO_IS_YUV (&info)) {
      if (range == V4L2_QUANTIZATION_FULL_RANGE
          && matrix == V4L2_YCBCR_ENC_601 && transfer == 0) {
        /* Full range BT.601 YCbCr encoding with unknown primaries and transfer
         * function most likely is JPEG */
        colorspace = V4L2_COLORSPACE_JPEG;
        transfer = V4L2_XFER_FUNC_SRGB;
      } else {
        /* SD streams likely use SMPTE170M and HD streams REC709 */
        if (width <= 720 && GST_VIDEO_INFO_HEIGHT (&info) <= 576)
          colorspace = V4L2_COLORSPACE_SMPTE170M;
        else
          colorspace = V4L2_COLORSPACE_REC709;
      }
    } else if (GST_VIDEO_INFO_IS_RGB (&info)) {
      colorspace = V4L2_COLORSPACE_SRGB;
      transfer = V4L2_XFER_FUNC_NONE;
    }
  }

  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "Desired format %dx%d, format "
      "%" GST_FOURCC_FORMAT " stride: %d", width, height,
      GST_FOURCC_ARGS (pixelformat), GST_VIDEO_INFO_PLANE_STRIDE (&info, 0));

  memset (&format, 0x00, sizeof (struct v4l2_format));
  format.type = v4l2object->type;

  if (is_mplane) {
    format.type = v4l2object->type;
    format.fmt.pix_mp.pixelformat = pixelformat;
    format.fmt.pix_mp.width = width;
    format.fmt.pix_mp.height = height;
    format.fmt.pix_mp.field = field;
    format.fmt.pix_mp.num_planes = n_v4l_planes;

    /* try to ask our prefered stride but it's not a failure if not
     * accepted */
    for (i = 0; i < n_v4l_planes; i++) {
      gint stride = GST_VIDEO_INFO_PLANE_STRIDE (&info, i);

      if (GST_VIDEO_FORMAT_INFO_IS_TILED (info.finfo))
        stride = GST_VIDEO_TILE_X_TILES (stride) <<
            GST_VIDEO_FORMAT_INFO_TILE_WS (info.finfo);

      format.fmt.pix_mp.plane_fmt[i].bytesperline = stride;
    }

    if (GST_VIDEO_INFO_FORMAT (&info) == GST_VIDEO_FORMAT_ENCODED)
      format.fmt.pix_mp.plane_fmt[0].sizeimage = ENCODED_BUFFER_SIZE;
  } else {
    gint stride = GST_VIDEO_INFO_PLANE_STRIDE (&info, 0);

    format.type = v4l2object->type;

    format.fmt.pix.width = width;
    format.fmt.pix.height = height;
    format.fmt.pix.pixelformat = pixelformat;
    format.fmt.pix.field = field;

    if (GST_VIDEO_FORMAT_INFO_IS_TILED (info.finfo))
      stride = GST_VIDEO_TILE_X_TILES (stride) <<
          GST_VIDEO_FORMAT_INFO_TILE_WS (info.finfo);

    /* try to ask our prefered stride */
    format.fmt.pix.bytesperline = stride;

    if (GST_VIDEO_INFO_FORMAT (&info) == GST_VIDEO_FORMAT_ENCODED)
      format.fmt.pix.sizeimage = ENCODED_BUFFER_SIZE;
  }

  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "Desired format is %dx%d, format "
      "%" GST_FOURCC_FORMAT ", nb planes %d", format.fmt.pix.width,
      format.fmt.pix_mp.height,
      GST_FOURCC_ARGS (format.fmt.pix.pixelformat),
      is_mplane ? format.fmt.pix_mp.num_planes : 1);

#ifndef GST_DISABLE_GST_DEBUG
  if (is_mplane) {
    for (i = 0; i < format.fmt.pix_mp.num_planes; i++)
      GST_DEBUG_OBJECT (v4l2object->dbg_obj, "  stride %d",
          format.fmt.pix_mp.plane_fmt[i].bytesperline);
  } else {
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "  stride %d",
        format.fmt.pix.bytesperline);
  }
#endif

  if (is_mplane) {
    format.fmt.pix_mp.colorspace = colorspace;
    format.fmt.pix_mp.quantization = range;
    format.fmt.pix_mp.ycbcr_enc = matrix;
    format.fmt.pix_mp.xfer_func = transfer;
  } else {
    format.fmt.pix.priv = V4L2_PIX_FMT_PRIV_MAGIC;
    format.fmt.pix.colorspace = colorspace;
    format.fmt.pix.quantization = range;
    format.fmt.pix.ycbcr_enc = matrix;
    format.fmt.pix.xfer_func = transfer;
  }

  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "Desired colorspace is %d:%d:%d:%d",
      colorspace, range, matrix, transfer);

  if (try_only) {
    if (v4l2object->ioctl (fd, VIDIOC_TRY_FMT, &format) < 0)
      goto try_fmt_failed;
  } else {
    if (v4l2object->ioctl (fd, VIDIOC_S_FMT, &format) < 0)
      goto set_fmt_failed;
  }

  if (is_mplane) {
    colorspace = format.fmt.pix_mp.colorspace;
    range = format.fmt.pix_mp.quantization;
    matrix = format.fmt.pix_mp.ycbcr_enc;
    transfer = format.fmt.pix_mp.xfer_func;
  } else {
    colorspace = format.fmt.pix.colorspace;
    range = format.fmt.pix.quantization;
    matrix = format.fmt.pix.ycbcr_enc;
    transfer = format.fmt.pix.xfer_func;
  }

  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "Got format of %dx%d, format "
      "%" GST_FOURCC_FORMAT ", nb planes %d, colorspace %d:%d:%d:%d",
      format.fmt.pix.width, format.fmt.pix_mp.height,
      GST_FOURCC_ARGS (format.fmt.pix.pixelformat),
      is_mplane ? format.fmt.pix_mp.num_planes : 1,
      colorspace, range, matrix, transfer);

#ifndef GST_DISABLE_GST_DEBUG
  if (is_mplane) {
    for (i = 0; i < format.fmt.pix_mp.num_planes; i++)
      GST_DEBUG_OBJECT (v4l2object->dbg_obj, "  stride %d, sizeimage %d",
          format.fmt.pix_mp.plane_fmt[i].bytesperline,
          format.fmt.pix_mp.plane_fmt[i].sizeimage);
  } else {
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "  stride %d, sizeimage %d",
        format.fmt.pix.bytesperline, format.fmt.pix.sizeimage);
  }
#endif

  if (format.fmt.pix.pixelformat != pixelformat)
    goto invalid_pixelformat;

  /* Only negotiate size with raw data.
   * For some codecs the dimensions are *not* in the bitstream, IIRC VC1
   * in ASF mode for example, there is also not reason for a driver to
   * change the size. */
  if (info.finfo->format != GST_VIDEO_FORMAT_ENCODED) {
    /* We can crop larger images */
    if (format.fmt.pix.width < width || format.fmt.pix.height < height)
      goto invalid_dimensions;

    /* Note, this will be adjusted if upstream has non-centered cropping. */
    align.padding_top = 0;
    align.padding_bottom = format.fmt.pix.height - height;
    align.padding_left = 0;
    align.padding_right = format.fmt.pix.width - width;
  }

  if (is_mplane && format.fmt.pix_mp.num_planes != n_v4l_planes)
    goto invalid_planes;

  /* used to check colorimetry and interlace mode fields presence */
  s = gst_caps_get_structure (caps, 0);

  if (!gst_v4l2_object_get_interlace_mode (format.fmt.pix.field,
          &info.interlace_mode))
    goto invalid_field;
  if (gst_structure_has_field (s, "interlace-mode")) {
    if (format.fmt.pix.field != field)
      goto invalid_field;
  }

  if (gst_v4l2_object_get_colorspace (&format, &info.colorimetry)) {
    s = gst_caps_get_structure (caps, 0);
    if (gst_structure_has_field (s, "colorimetry")) {
      if (!gst_v4l2_video_colorimetry_matches (&info.colorimetry,
              gst_structure_get_string (s, "colorimetry")))
        goto invalid_colorimetry;
    }
  } else {
    /* The driver (or libv4l2) is miss-behaving, allow caps to be renegotiated with upstream elements' caps */
    disable_colorimetry = TRUE;
  }

  /* In case we have skipped the try_fmt probes, we'll need to set the
   * colorimetry back into the caps. */
  if (v4l2object->skip_try_fmt_probes) {
    if (!disable_colorimetry && !gst_structure_has_field (s, "colorimetry")) {
      gchar *str = gst_video_colorimetry_to_string (&info.colorimetry);
      gst_structure_set (s, "colorimetry", G_TYPE_STRING, str, NULL);
      g_free (str);
    }
  }

  if (try_only)                 /* good enough for trying only */
    return TRUE;

  if (GST_VIDEO_INFO_HAS_ALPHA (&info)) {
    struct v4l2_control ctl = { 0, };
    ctl.id = V4L2_CID_ALPHA_COMPONENT;
    ctl.value = 0xff;

    if (v4l2object->ioctl (fd, VIDIOC_S_CTRL, &ctl) < 0)
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "Failed to set alpha component value");
  }

  /* Is there a reason we require the caller to always specify a framerate? */
  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "Desired framerate: %u/%u", fps_n,
      fps_d);

  memset (&streamparm, 0x00, sizeof (struct v4l2_streamparm));
  streamparm.type = v4l2object->type;

  if (v4l2object->ioctl (fd, VIDIOC_G_PARM, &streamparm) < 0)
    goto get_parm_failed;

  if (v4l2object->type == V4L2_BUF_TYPE_VIDEO_CAPTURE
      || v4l2object->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
    GST_VIDEO_INFO_FPS_N (&info) =
        streamparm.parm.capture.timeperframe.denominator;
    GST_VIDEO_INFO_FPS_D (&info) =
        streamparm.parm.capture.timeperframe.numerator;

    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "Got capture framerate: %u/%u",
        streamparm.parm.capture.timeperframe.denominator,
        streamparm.parm.capture.timeperframe.numerator);

    /* We used to skip frame rate setup if the camera was already setup
     * with the requested frame rate. This breaks some cameras though,
     * causing them to not output data (several models of Thinkpad cameras
     * have this problem at least).
     * So, don't skip. */
    GST_LOG_OBJECT (v4l2object->dbg_obj, "Setting capture framerate to %u/%u",
        fps_n, fps_d);
    /* We want to change the frame rate, so check whether we can. Some cheap USB
     * cameras don't have the capability */
    if ((streamparm.parm.capture.capability & V4L2_CAP_TIMEPERFRAME) == 0) {
      GST_DEBUG_OBJECT (v4l2object->dbg_obj,
          "Not setting capture framerate (not supported)");
      goto done;
    }

    /* Note: V4L2 wants the frame interval, we have the frame rate */
    streamparm.parm.capture.timeperframe.numerator = fps_d;
    streamparm.parm.capture.timeperframe.denominator = fps_n;

    /* some cheap USB cam's won't accept any change */
    if (v4l2object->ioctl (fd, VIDIOC_S_PARM, &streamparm) < 0)
      goto set_parm_failed;

    if (streamparm.parm.capture.timeperframe.numerator > 0 &&
        streamparm.parm.capture.timeperframe.denominator > 0) {
      /* get new values */
      fps_d = streamparm.parm.capture.timeperframe.numerator;
      fps_n = streamparm.parm.capture.timeperframe.denominator;

      GST_INFO_OBJECT (v4l2object->dbg_obj, "Set capture framerate to %u/%u",
          fps_n, fps_d);
    } else {
      /* fix v4l2 capture driver to provide framerate values */
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "Reuse caps framerate %u/%u - fix v4l2 capture driver", fps_n, fps_d);
    }

    GST_VIDEO_INFO_FPS_N (&info) = fps_n;
    GST_VIDEO_INFO_FPS_D (&info) = fps_d;
  } else if (v4l2object->type == V4L2_BUF_TYPE_VIDEO_OUTPUT
      || v4l2object->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
    GST_VIDEO_INFO_FPS_N (&info) =
        streamparm.parm.output.timeperframe.denominator;
    GST_VIDEO_INFO_FPS_D (&info) =
        streamparm.parm.output.timeperframe.numerator;

    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "Got output framerate: %u/%u",
        streamparm.parm.output.timeperframe.denominator,
        streamparm.parm.output.timeperframe.numerator);

    GST_LOG_OBJECT (v4l2object->dbg_obj, "Setting output framerate to %u/%u",
        fps_n, fps_d);
    if ((streamparm.parm.output.capability & V4L2_CAP_TIMEPERFRAME) == 0) {
      GST_DEBUG_OBJECT (v4l2object->dbg_obj,
          "Not setting output framerate (not supported)");
      goto done;
    }

    /* Note: V4L2 wants the frame interval, we have the frame rate */
    streamparm.parm.output.timeperframe.numerator = fps_d;
    streamparm.parm.output.timeperframe.denominator = fps_n;

    if (v4l2object->ioctl (fd, VIDIOC_S_PARM, &streamparm) < 0)
      goto set_parm_failed;

    if (streamparm.parm.output.timeperframe.numerator > 0 &&
        streamparm.parm.output.timeperframe.denominator > 0) {
      /* get new values */
      fps_d = streamparm.parm.output.timeperframe.numerator;
      fps_n = streamparm.parm.output.timeperframe.denominator;

      GST_INFO_OBJECT (v4l2object->dbg_obj, "Set output framerate to %u/%u",
          fps_n, fps_d);
    } else {
      /* fix v4l2 output driver to provide framerate values */
      GST_WARNING_OBJECT (v4l2object->dbg_obj,
          "Reuse caps framerate %u/%u - fix v4l2 output driver", fps_n, fps_d);
    }

    GST_VIDEO_INFO_FPS_N (&info) = fps_n;
    GST_VIDEO_INFO_FPS_D (&info) = fps_d;
  }

done:
  features = gst_caps_get_features (caps, 0);
  if (features &&
      gst_caps_features_contains (features, GST_CAPS_FEATURE_MEMORY_XLNX_LL)) {
    GST_DEBUG_OBJECT (v4l2object, "Found XLNX-LL memory feature");
    v4l2object->xlnx_ll = TRUE;
    /* HACK: Always reset low latency mode to ensure v4l2 cache is updated */
    if (!gst_v4l2_object_set_low_latency_capture_mode (v4l2object, FALSE))
      GST_ERROR_OBJECT (v4l2object, "Driver failed to deactivate XLNX-LL");
    if (!gst_v4l2_object_set_low_latency_capture_mode (v4l2object, TRUE)) {
      GST_ERROR_OBJECT (v4l2object, "Driver failed to activate XLNX-LL");
      v4l2object->xlnx_ll = FALSE;
    }
  }

  /* add boolean return, so we can fail on drivers bugs */
  gst_v4l2_object_save_format (v4l2object, fmtdesc, &format, &info, &align);

  /* now configure the pool */
  if (!gst_v4l2_object_setup_pool (v4l2object, caps))
    goto pool_failed;

  return TRUE;

  /* ERRORS */
invalid_caps:
  {
    GST_DEBUG_OBJECT (v4l2object->dbg_obj, "can't parse caps %" GST_PTR_FORMAT,
        caps);
    return FALSE;
  }
try_fmt_failed:
  {
    if (errno == EINVAL) {
      GST_V4L2_ERROR (error, RESOURCE, SETTINGS,
          (_("Device '%s' has no supported format"), v4l2object->videodev),
          ("Call to TRY_FMT failed for %" GST_FOURCC_FORMAT " @ %dx%d: %s",
              GST_FOURCC_ARGS (pixelformat), width, height,
              g_strerror (errno)));
    } else {
      GST_V4L2_ERROR (error, RESOURCE, FAILED,
          (_("Device '%s' failed during initialization"),
              v4l2object->videodev),
          ("Call to TRY_FMT failed for %" GST_FOURCC_FORMAT " @ %dx%d: %s",
              GST_FOURCC_ARGS (pixelformat), width, height,
              g_strerror (errno)));
    }
    return FALSE;
  }
set_fmt_failed:
  {
    if (errno == EBUSY) {
      GST_V4L2_ERROR (error, RESOURCE, BUSY,
          (_("Device '%s' is busy"), v4l2object->videodev),
          ("Call to S_FMT failed for %" GST_FOURCC_FORMAT " @ %dx%d: %s",
              GST_FOURCC_ARGS (pixelformat), width, height,
              g_strerror (errno)));
    } else if (errno == EINVAL) {
      GST_V4L2_ERROR (error, RESOURCE, SETTINGS,
          (_("Device '%s' has no supported format"), v4l2object->videodev),
          ("Call to S_FMT failed for %" GST_FOURCC_FORMAT " @ %dx%d: %s",
              GST_FOURCC_ARGS (pixelformat), width, height,
              g_strerror (errno)));
    } else {
      GST_V4L2_ERROR (error, RESOURCE, FAILED,
          (_("Device '%s' failed during initialization"),
              v4l2object->videodev),
          ("Call to S_FMT failed for %" GST_FOURCC_FORMAT " @ %dx%d: %s",
              GST_FOURCC_ARGS (pixelformat), width, height,
              g_strerror (errno)));
    }
    return FALSE;
  }
invalid_dimensions:
  {
    GST_V4L2_ERROR (error, RESOURCE, SETTINGS,
        (_("Device '%s' cannot capture at %dx%d"),
            v4l2object->videodev, width, height),
        ("Tried to capture at %dx%d, but device returned size %dx%d",
            width, height, format.fmt.pix.width, format.fmt.pix.height));
    return FALSE;
  }
invalid_pixelformat:
  {
    GST_V4L2_ERROR (error, RESOURCE, SETTINGS,
        (_("Device '%s' cannot capture in the specified format"),
            v4l2object->videodev),
        ("Tried to capture in %" GST_FOURCC_FORMAT
            ", but device returned format" " %" GST_FOURCC_FORMAT,
            GST_FOURCC_ARGS (pixelformat),
            GST_FOURCC_ARGS (format.fmt.pix.pixelformat)));
    return FALSE;
  }
invalid_planes:
  {
    GST_V4L2_ERROR (error, RESOURCE, SETTINGS,
        (_("Device '%s' does support non-contiguous planes"),
            v4l2object->videodev),
        ("Device wants %d planes", format.fmt.pix_mp.num_planes));
    return FALSE;
  }
invalid_field:
  {
    enum v4l2_field wanted_field;

    if (is_mplane)
      wanted_field = format.fmt.pix_mp.field;
    else
      wanted_field = format.fmt.pix.field;

    GST_V4L2_ERROR (error, RESOURCE, SETTINGS,
        (_("Device '%s' does not support %s interlacing"),
            v4l2object->videodev,
            field == V4L2_FIELD_NONE ? "progressive" : "interleaved"),
        ("Device wants %s interlacing",
            wanted_field == V4L2_FIELD_NONE ? "progressive" : "interleaved"));
    return FALSE;
  }
invalid_colorimetry:
  {
    gchar *wanted_colorimetry;

    wanted_colorimetry = gst_video_colorimetry_to_string (&info.colorimetry);

    GST_V4L2_ERROR (error, RESOURCE, SETTINGS,
        (_("Device '%s' does not support %s colorimetry"),
            v4l2object->videodev, gst_structure_get_string (s, "colorimetry")),
        ("Device wants %s colorimetry", wanted_colorimetry));

    g_free (wanted_colorimetry);
    return FALSE;
  }
get_parm_failed:
  {
    /* it's possible that this call is not supported */
    if (errno != EINVAL && errno != ENOTTY) {
      GST_V4L2_ERROR (error, RESOURCE, SETTINGS,
          (_("Could not get parameters on device '%s'"),
              v4l2object->videodev), GST_ERROR_SYSTEM);
    }
    goto done;
  }
set_parm_failed:
  {
    GST_V4L2_ERROR (error, RESOURCE, SETTINGS,
        (_("Video device did not accept new frame rate setting.")),
        GST_ERROR_SYSTEM);
    goto done;
  }
pool_failed:
  {
    /* setup_pool already send the error */
    return FALSE;
  }
}

gboolean
gst_v4l2_object_set_format (GstV4l2Object * v4l2object, GstCaps * caps,
    GstV4l2Error * error)
{
  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "Setting format to %" GST_PTR_FORMAT,
      caps);
  return gst_v4l2_object_set_format_full (v4l2object, caps, FALSE, error);
}

gboolean
gst_v4l2_object_try_format (GstV4l2Object * v4l2object, GstCaps * caps,
    GstV4l2Error * error)
{
  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "Trying format %" GST_PTR_FORMAT,
      caps);
  return gst_v4l2_object_set_format_full (v4l2object, caps, TRUE, error);
}

/**
 * gst_v4l2_object_acquire_format:
 * @v4l2object the object
 * @info a GstVideoInfo to be filled
 *
 * Acquire the driver choosen format. This is useful in decoder or encoder elements where
 * the output format is choosen by the HW.
 *
 * Returns: %TRUE on success, %FALSE on failure.
 */
gboolean
gst_v4l2_object_acquire_format (GstV4l2Object * v4l2object, GstVideoInfo * info)
{
  struct v4l2_fmtdesc *fmtdesc;
  struct v4l2_format fmt;
  struct v4l2_crop crop;
  struct v4l2_selection sel;
  struct v4l2_rect *r = NULL;
  GstVideoFormat format;
  guint width, height;
  GstVideoAlignment align;
  GstVideoInterlaceMode interlace_mode;

  gst_video_info_init (info);
  gst_video_alignment_reset (&align);

  memset (&fmt, 0x00, sizeof (struct v4l2_format));
  fmt.type = v4l2object->type;
  if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_G_FMT, &fmt) < 0)
    goto get_fmt_failed;

  fmtdesc = gst_v4l2_object_get_format_from_fourcc (v4l2object,
      fmt.fmt.pix.pixelformat);
  if (fmtdesc == NULL)
    goto unsupported_format;

  /* No need to care about mplane, the four first params are the same */
  format = gst_v4l2_object_v4l2fourcc_to_video_format (fmt.fmt.pix.pixelformat);

  /* fails if we do no translate the fmt.pix.pixelformat to GstVideoFormat */
  if (format == GST_VIDEO_FORMAT_UNKNOWN)
    goto unsupported_format;

  if (fmt.fmt.pix.width == 0 || fmt.fmt.pix.height == 0)
    goto invalid_dimensions;

  width = fmt.fmt.pix.width;
  height = fmt.fmt.pix.height;

  /* Use the default compose rectangle */
  memset (&sel, 0, sizeof (struct v4l2_selection));
  sel.type = v4l2object->type;
  sel.target = V4L2_SEL_TGT_COMPOSE;
  if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_G_SELECTION, &sel) >= 0) {
    r = &sel.r;
  } else {
    /* For ancient kernels, fall back to G_CROP */
    memset (&crop, 0, sizeof (struct v4l2_crop));
    crop.type = v4l2object->type;
    if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_G_CROP, &crop) >= 0)
      r = &crop.c;
  }
  if (r) {
    align.padding_left = r->left;
    align.padding_top = r->top;
    align.padding_right = width - r->width - r->left;
    align.padding_bottom = height - r->height - r->top;
    width = r->width;
    height = r->height;
  }

  switch (fmt.fmt.pix.field) {
    case V4L2_FIELD_ANY:
    case V4L2_FIELD_NONE:
      interlace_mode = GST_VIDEO_INTERLACE_MODE_PROGRESSIVE;
      break;
    case V4L2_FIELD_INTERLACED:
    case V4L2_FIELD_INTERLACED_TB:
    case V4L2_FIELD_INTERLACED_BT:
      interlace_mode = GST_VIDEO_INTERLACE_MODE_INTERLEAVED;
      break;
    case V4L2_FIELD_ALTERNATE:
      interlace_mode = GST_VIDEO_INTERLACE_MODE_ALTERNATE;
      break;
    default:
      goto unsupported_field;
  }

  gst_video_info_set_interlaced_format (info, format, interlace_mode, width,
      height);

  gst_v4l2_object_get_colorspace (&fmt, &info->colorimetry);

  gst_v4l2_object_save_format (v4l2object, fmtdesc, &fmt, info, &align);

  /* Shall we setup the pool ? */

  return TRUE;

get_fmt_failed:
  {
    GST_ELEMENT_WARNING (v4l2object->element, RESOURCE, SETTINGS,
        (_("Video device did not provide output format.")), GST_ERROR_SYSTEM);
    return FALSE;
  }
invalid_dimensions:
  {
    GST_ELEMENT_WARNING (v4l2object->element, RESOURCE, SETTINGS,
        (_("Video device returned invalid dimensions.")),
        ("Expected non 0 dimensions, got %dx%d", fmt.fmt.pix.width,
            fmt.fmt.pix.height));
    return FALSE;
  }
unsupported_field:
  {
    GST_ELEMENT_ERROR (v4l2object->element, RESOURCE, SETTINGS,
        (_("Video device uses an unsupported interlacing method.")),
        ("V4L2 field type %d not supported", fmt.fmt.pix.field));
    return FALSE;
  }
unsupported_format:
  {
    GST_ELEMENT_ERROR (v4l2object->element, RESOURCE, SETTINGS,
        (_("Video device uses an unsupported pixel format.")),
        ("V4L2 format %" GST_FOURCC_FORMAT " not supported",
            GST_FOURCC_ARGS (fmt.fmt.pix.pixelformat)));
    return FALSE;
  }
}

gboolean
gst_v4l2_object_set_crop (GstV4l2Object * obj)
{
  struct v4l2_selection sel = { 0 };
  struct v4l2_crop crop = { 0 };

  sel.type = obj->type;
  sel.target = V4L2_SEL_TGT_COMPOSE;
  sel.flags = 0;
  sel.r.left = obj->align.padding_left;
  sel.r.top = obj->align.padding_top;
  sel.r.width = obj->info.width;
  sel.r.height = GST_VIDEO_INFO_FIELD_HEIGHT (&obj->info);

  if (obj->force_ntsc_tv && sel.r.height == 240) {
    sel.r.height = 243;
    sel.r.width = 720;
    GST_LOG_OBJECT (obj->dbg_obj, "Forcing crop to TV D1 NTSC (720x486i)");
  }

  crop.type = obj->type;
  crop.c = sel.r;

  if (obj->align.padding_left + obj->align.padding_top +
      obj->align.padding_right + obj->align.padding_bottom == 0) {
    GST_DEBUG_OBJECT (obj->dbg_obj, "no cropping needed");
    return TRUE;
  }

  GST_DEBUG_OBJECT (obj->dbg_obj,
      "Desired cropping left %u, top %u, size %ux%u", crop.c.left, crop.c.top,
      crop.c.width, crop.c.height);

  if (obj->ioctl (obj->video_fd, VIDIOC_S_SELECTION, &sel) < 0) {
    if (errno != ENOTTY) {
      GST_WARNING_OBJECT (obj->dbg_obj,
          "Failed to set crop rectangle with VIDIOC_S_SELECTION: %s",
          g_strerror (errno));
      return FALSE;
    } else {
      if (obj->ioctl (obj->video_fd, VIDIOC_S_CROP, &crop) < 0) {
        GST_WARNING_OBJECT (obj->dbg_obj, "VIDIOC_S_CROP failed");
        return FALSE;
      }

      if (obj->ioctl (obj->video_fd, VIDIOC_G_CROP, &crop) < 0) {
        GST_WARNING_OBJECT (obj->dbg_obj, "VIDIOC_G_CROP failed");
        return FALSE;
      }

      sel.r = crop.c;
    }
  }

  GST_DEBUG_OBJECT (obj->dbg_obj,
      "Got cropping left %u, top %u, size %ux%u", crop.c.left, crop.c.top,
      crop.c.width, crop.c.height);

  return TRUE;
}

gboolean
gst_v4l2_object_caps_equal (GstV4l2Object * v4l2object, GstCaps * caps)
{
  GstStructure *config;
  GstCaps *oldcaps;
  gboolean ret;

  if (!v4l2object->pool)
    return FALSE;

  config = gst_buffer_pool_get_config (v4l2object->pool);
  gst_buffer_pool_config_get_params (config, &oldcaps, NULL, NULL, NULL);

  ret = oldcaps && gst_caps_is_equal (caps, oldcaps);

  gst_structure_free (config);

  return ret;
}

gboolean
gst_v4l2_object_caps_is_subset (GstV4l2Object * v4l2object, GstCaps * caps)
{
  GstStructure *config;
  GstCaps *oldcaps;
  gboolean ret;

  if (!v4l2object->pool)
    return FALSE;

  config = gst_buffer_pool_get_config (v4l2object->pool);
  gst_buffer_pool_config_get_params (config, &oldcaps, NULL, NULL, NULL);

  ret = oldcaps && gst_caps_is_subset (oldcaps, caps);

  gst_structure_free (config);

  return ret;
}

GstCaps *
gst_v4l2_object_get_current_caps (GstV4l2Object * v4l2object)
{
  GstStructure *config;
  GstCaps *oldcaps;

  if (!v4l2object->pool)
    return NULL;

  config = gst_buffer_pool_get_config (v4l2object->pool);
  gst_buffer_pool_config_get_params (config, &oldcaps, NULL, NULL, NULL);

  if (oldcaps)
    gst_caps_ref (oldcaps);

  gst_structure_free (config);

  return oldcaps;
}

gboolean
gst_v4l2_object_unlock (GstV4l2Object * v4l2object)
{
  gboolean ret = TRUE;

  GST_LOG_OBJECT (v4l2object->dbg_obj, "start flushing");

  if (v4l2object->pool && gst_buffer_pool_is_active (v4l2object->pool))
    gst_buffer_pool_set_flushing (v4l2object->pool, TRUE);

  return ret;
}

gboolean
gst_v4l2_object_unlock_stop (GstV4l2Object * v4l2object)
{
  gboolean ret = TRUE;

  GST_LOG_OBJECT (v4l2object->dbg_obj, "stop flushing");

  if (v4l2object->pool && gst_buffer_pool_is_active (v4l2object->pool))
    gst_buffer_pool_set_flushing (v4l2object->pool, FALSE);

  return ret;
}

gboolean
gst_v4l2_object_stop (GstV4l2Object * v4l2object)
{
  GST_DEBUG_OBJECT (v4l2object->dbg_obj, "stopping");

  if (!GST_V4L2_IS_OPEN (v4l2object))
    goto done;
  if (!GST_V4L2_IS_ACTIVE (v4l2object))
    goto done;

  if (v4l2object->pool) {
    if (!gst_v4l2_buffer_pool_orphan (&v4l2object->pool)) {
      GST_DEBUG_OBJECT (v4l2object->dbg_obj, "deactivating pool");
      gst_buffer_pool_set_active (v4l2object->pool, FALSE);
      gst_object_unref (v4l2object->pool);
    }
    v4l2object->pool = NULL;
  }

  if (v4l2object->sync_chan.enabled) {
    xvfbsync_enc_sync_chan_depopulate (&v4l2object->enc_sync_chan);
    close (v4l2object->syncip.fd);
    if (!gst_v4l2_object_set_low_latency_capture_mode (v4l2object, FALSE))
      GST_ERROR_OBJECT (v4l2object, "Driver failed to deactivate XLNX-LL");
  }

  GST_V4L2_SET_INACTIVE (v4l2object);

done:
  return TRUE;
}

GstCaps *
gst_v4l2_object_probe_caps (GstV4l2Object * v4l2object, GstCaps * filter)
{
  GstCaps *ret;
  GSList *walk;
  GSList *formats;

  formats = gst_v4l2_object_get_format_list (v4l2object);

  ret = gst_caps_new_empty ();

  if (v4l2object->keep_aspect && !v4l2object->par) {
    struct v4l2_cropcap cropcap;

    memset (&cropcap, 0, sizeof (cropcap));

    cropcap.type = v4l2object->type;
    if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_CROPCAP, &cropcap) < 0) {
      if (errno != ENOTTY)
        GST_WARNING_OBJECT (v4l2object->dbg_obj,
            "Failed to probe pixel aspect ratio with VIDIOC_CROPCAP: %s",
            g_strerror (errno));
    } else if (cropcap.pixelaspect.numerator && cropcap.pixelaspect.denominator) {
      v4l2object->par = g_new0 (GValue, 1);
      g_value_init (v4l2object->par, GST_TYPE_FRACTION);
      gst_value_set_fraction (v4l2object->par, cropcap.pixelaspect.numerator,
          cropcap.pixelaspect.denominator);
    }
  }

  for (walk = formats; walk; walk = walk->next) {
    struct v4l2_fmtdesc *format;
    GstStructure *template;
    GstCaps *tmp;

    format = (struct v4l2_fmtdesc *) walk->data;

    template = gst_v4l2_object_v4l2fourcc_to_bare_struct (format->pixelformat);

    if (!template) {
      GST_DEBUG_OBJECT (v4l2object->dbg_obj,
          "unknown format %" GST_FOURCC_FORMAT,
          GST_FOURCC_ARGS (format->pixelformat));
      continue;
    }

    /* If we have a filter, check if we need to probe this format or not */
    if (filter) {
      GstCaps *format_caps = gst_caps_new_empty ();

      gst_caps_append_structure (format_caps, gst_structure_copy (template));

      if (!gst_caps_can_intersect (format_caps, filter)) {
        gst_caps_unref (format_caps);
        gst_structure_free (template);
        continue;
      }

      gst_caps_unref (format_caps);
    }

    tmp = gst_v4l2_object_probe_caps_for_format (v4l2object,
        format->pixelformat, template);
    if (tmp)
      gst_caps_append (ret, tmp);

    gst_structure_free (template);
  }

  if (filter) {
    GstCaps *tmp;

    tmp = ret;
    ret = gst_caps_intersect_full (filter, ret, GST_CAPS_INTERSECT_FIRST);
    gst_caps_unref (tmp);
  }

  GST_INFO_OBJECT (v4l2object->dbg_obj, "probed caps: %" GST_PTR_FORMAT, ret);

  return ret;
}

GstCaps *
gst_v4l2_object_get_caps (GstV4l2Object * v4l2object, GstCaps * filter)
{
  GstCaps *ret;

  if (v4l2object->probed_caps == NULL)
    v4l2object->probed_caps = gst_v4l2_object_probe_caps (v4l2object, NULL);

  if (filter) {
    ret = gst_caps_intersect_full (filter, v4l2object->probed_caps,
        GST_CAPS_INTERSECT_FIRST);
  } else {
    ret = gst_caps_ref (v4l2object->probed_caps);
  }

  return ret;
}

static gboolean
gst_v4l2_object_match_buffer_layout (GstV4l2Object * obj, guint n_planes,
    gsize offset[GST_VIDEO_MAX_PLANES], gint stride[GST_VIDEO_MAX_PLANES],
    gsize buffer_size, guint padded_height)
{
  guint p;
  gboolean need_fmt_update = FALSE;

  if (n_planes != GST_VIDEO_INFO_N_PLANES (&obj->info)) {
    GST_WARNING_OBJECT (obj->dbg_obj,
        "Cannot match buffers with different number planes");
    return FALSE;
  }

  for (p = 0; p < n_planes; p++) {
    if (stride[p] < obj->info.stride[p]) {
      GST_DEBUG_OBJECT (obj->dbg_obj,
          "Not matching as remote stride %i is smaller than %i on plane %u",
          stride[p], obj->info.stride[p], p);
      return FALSE;
    } else if (stride[p] > obj->info.stride[p]) {
      GST_LOG_OBJECT (obj->dbg_obj,
          "remote stride %i is higher than %i on plane %u",
          stride[p], obj->info.stride[p], p);
      need_fmt_update = TRUE;
    }

    if (offset[p] < obj->info.offset[p]) {
      GST_DEBUG_OBJECT (obj->dbg_obj,
          "Not matching as offset %" G_GSIZE_FORMAT
          " is smaller than %" G_GSIZE_FORMAT " on plane %u",
          offset[p], obj->info.offset[p], p);
      return FALSE;
    } else if (offset[p] > obj->info.offset[p]) {
      GST_LOG_OBJECT (obj->dbg_obj,
          "Remote offset %" G_GSIZE_FORMAT
          " is higher than %" G_GSIZE_FORMAT " on plane %u",
          offset[p], obj->info.offset[p], p);
      need_fmt_update = TRUE;
    }
  }

  if (need_fmt_update) {
    struct v4l2_format format;
    gint wanted_stride[GST_VIDEO_MAX_PLANES] = { 0, };

    format = obj->format;

    if (padded_height) {
      GST_DEBUG_OBJECT (obj->dbg_obj, "Padded height %u", padded_height);

      obj->align.padding_bottom =
          padded_height - GST_VIDEO_INFO_FIELD_HEIGHT (&obj->info);
    } else {
      GST_WARNING_OBJECT (obj->dbg_obj,
          "Failed to compute padded height; keep the default one");
      padded_height = format.fmt.pix_mp.height;
    }

    /* update the current format with the stride we want to import from */
    if (V4L2_TYPE_IS_MULTIPLANAR (obj->type)) {
      guint i;

      GST_DEBUG_OBJECT (obj->dbg_obj, "Wanted strides:");

      for (i = 0; i < obj->n_v4l2_planes; i++) {
        gint plane_stride = stride[i];

        if (GST_VIDEO_FORMAT_INFO_IS_TILED (obj->info.finfo))
          plane_stride = GST_VIDEO_TILE_X_TILES (plane_stride) <<
              GST_VIDEO_FORMAT_INFO_TILE_WS (obj->info.finfo);

        format.fmt.pix_mp.plane_fmt[i].bytesperline = plane_stride;
        format.fmt.pix_mp.height = padded_height;
        wanted_stride[i] = plane_stride;
        GST_DEBUG_OBJECT (obj->dbg_obj, "    [%u] %i", i, wanted_stride[i]);
      }
    } else {
      gint plane_stride = stride[0];

      GST_DEBUG_OBJECT (obj->dbg_obj, "Wanted stride: %i", plane_stride);

      if (GST_VIDEO_FORMAT_INFO_IS_TILED (obj->info.finfo))
        plane_stride = GST_VIDEO_TILE_X_TILES (plane_stride) <<
            GST_VIDEO_FORMAT_INFO_TILE_WS (obj->info.finfo);

      format.fmt.pix.bytesperline = plane_stride;
      format.fmt.pix.height = padded_height;
      wanted_stride[0] = plane_stride;
    }

    if (obj->ioctl (obj->video_fd, VIDIOC_S_FMT, &format) < 0) {
      GST_WARNING_OBJECT (obj->dbg_obj,
          "Something went wrong trying to update current format: %s",
          g_strerror (errno));
      return FALSE;
    }

    gst_v4l2_object_save_format (obj, obj->fmtdesc, &format, &obj->info,
        &obj->align);

    if (V4L2_TYPE_IS_MULTIPLANAR (obj->type)) {
      guint i;

      for (i = 0; i < obj->n_v4l2_planes; i++) {
        if (format.fmt.pix_mp.plane_fmt[i].bytesperline != wanted_stride[i]) {
          GST_DEBUG_OBJECT (obj->dbg_obj,
              "[%i] Driver did not accept the new stride (wants %i, got %i)",
              i, wanted_stride[i], format.fmt.pix_mp.plane_fmt[i].bytesperline);
          return FALSE;
        }
      }

      if (format.fmt.pix_mp.height != padded_height) {
        GST_DEBUG_OBJECT (obj->dbg_obj,
            "Driver did not accept the padded height (wants %i, got %i)",
            padded_height, format.fmt.pix_mp.height);
      }
    } else {
      if (format.fmt.pix.bytesperline != wanted_stride[0]) {
        GST_DEBUG_OBJECT (obj->dbg_obj,
            "Driver did not accept the new stride (wants %i, got %i)",
            wanted_stride[0], format.fmt.pix.bytesperline);
        return FALSE;
      }

      if (format.fmt.pix.height != padded_height) {
        GST_DEBUG_OBJECT (obj->dbg_obj,
            "Driver did not accept the padded height (wants %i, got %i)",
            padded_height, format.fmt.pix.height);
      }
    }
  }

  if (obj->align.padding_bottom) {
    /* Crop because of vertical padding */
    GST_DEBUG_OBJECT (obj->dbg_obj, "crop because of bottom padding of %d",
        obj->align.padding_bottom);
    gst_v4l2_object_set_crop (obj);
  }

  return TRUE;
}

static gboolean
validate_video_meta_struct (GstV4l2Object * obj, const GstStructure * s)
{
  guint i;

  for (i = 0; i < gst_structure_n_fields (s); i++) {
    const gchar *name = gst_structure_nth_field_name (s, i);

    if (!g_str_equal (name, "padding-top")
        && !g_str_equal (name, "padding-bottom")
        && !g_str_equal (name, "padding-left")
        && !g_str_equal (name, "padding-right")) {
      GST_WARNING_OBJECT (obj->dbg_obj, "Unknown video meta field: '%s'", name);
      return FALSE;
    }
  }

  return TRUE;
}

static gboolean
gst_v4l2_object_match_buffer_layout_from_struct (GstV4l2Object * obj,
    const GstStructure * s, GstCaps * caps, guint buffer_size)
{
  GstVideoInfo info;
  GstVideoAlignment align;
  gsize plane_size[GST_VIDEO_MAX_PLANES];

  if (!validate_video_meta_struct (obj, s))
    return FALSE;

  if (!gst_video_info_from_caps (&info, caps)) {
    GST_WARNING_OBJECT (obj->dbg_obj, "Failed to create video info");
    return FALSE;
  }

  gst_video_alignment_reset (&align);

  gst_structure_get_uint (s, "padding-top", &align.padding_top);
  gst_structure_get_uint (s, "padding-bottom", &align.padding_bottom);
  gst_structure_get_uint (s, "padding-left", &align.padding_left);
  gst_structure_get_uint (s, "padding-right", &align.padding_right);

  if (align.padding_top || align.padding_bottom || align.padding_left ||
      align.padding_right) {
    GST_DEBUG_OBJECT (obj->dbg_obj,
        "Upstream requested padding (top: %d bottom: %d left: %d right: %d)",
        align.padding_top, align.padding_bottom, align.padding_left,
        align.padding_right);
  }

  if (!gst_video_info_align_full (&info, &align, plane_size)) {
    GST_WARNING_OBJECT (obj->dbg_obj, "Failed to align video info");
    return FALSE;
  }

  if (GST_VIDEO_INFO_SIZE (&info) != buffer_size) {
    GST_WARNING_OBJECT (obj->dbg_obj,
        "Requested buffer size (%d) doesn't match video info size (%"
        G_GSIZE_FORMAT ")", buffer_size, GST_VIDEO_INFO_SIZE (&info));
    return FALSE;
  }

  GST_DEBUG_OBJECT (obj->dbg_obj,
      "try matching buffer layout requested by downstream");

  gst_v4l2_object_match_buffer_layout (obj, GST_VIDEO_INFO_N_PLANES (&info),
      info.offset, info.stride, buffer_size,
      GST_VIDEO_INFO_PLANE_HEIGHT (&info, 0, plane_size));

  return TRUE;
}

gboolean
gst_v4l2_object_decide_allocation (GstV4l2Object * obj, GstQuery * query)
{
  GstCaps *caps;
  GstBufferPool *pool = NULL, *other_pool = NULL;
  GstStructure *config;
  guint size, min, max, own_min = 0;
  gboolean update;
  gboolean has_video_meta;
  gboolean can_share_own_pool, pushing_from_our_pool = FALSE;
  GstAllocator *allocator = NULL;
  GstAllocationParams params = { 0 };
  guint video_idx;

  GST_DEBUG_OBJECT (obj->dbg_obj, "decide allocation");

  g_return_val_if_fail (obj->type == V4L2_BUF_TYPE_VIDEO_CAPTURE ||
      obj->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE, FALSE);

  gst_query_parse_allocation (query, &caps, NULL);

  if (obj->pool == NULL) {
    if (!gst_v4l2_object_setup_pool (obj, caps))
      goto pool_failed;
  }

  if (gst_query_get_n_allocation_params (query) > 0)
    gst_query_parse_nth_allocation_param (query, 0, &allocator, &params);

  if (gst_query_get_n_allocation_pools (query) > 0) {
    gst_query_parse_nth_allocation_pool (query, 0, &pool, &size, &min, &max);
    update = TRUE;
  } else {
    pool = NULL;
    min = max = 0;
    size = 0;
    update = FALSE;
  }

  GST_DEBUG_OBJECT (obj->dbg_obj, "allocation: size:%u min:%u max:%u pool:%"
      GST_PTR_FORMAT, size, min, max, pool);

  has_video_meta =
      gst_query_find_allocation_meta (query, GST_VIDEO_META_API_TYPE,
      &video_idx);

  if (has_video_meta) {
    const GstStructure *params;
    gst_query_parse_nth_allocation_meta (query, video_idx, &params);

    if (params)
      gst_v4l2_object_match_buffer_layout_from_struct (obj, params, caps, size);
  }

  can_share_own_pool = (has_video_meta || !obj->need_video_meta);

  gst_v4l2_get_driver_min_buffers (obj);
  /* We can't share our own pool, if it exceed V4L2 capacity */
  if (min + obj->min_buffers + 1 > VIDEO_MAX_FRAME)
    can_share_own_pool = FALSE;

  /* select a pool */
  switch (obj->mode) {
    case GST_V4L2_IO_RW:
      if (pool) {
        /* in READ/WRITE mode, prefer a downstream pool because our own pool
         * doesn't help much, we have to write to it as well */
        GST_DEBUG_OBJECT (obj->dbg_obj,
            "read/write mode: using downstream pool");
        /* use the bigest size, when we use our own pool we can't really do any
         * other size than what the hardware gives us but for downstream pools
         * we can try */
        size = MAX (size, obj->info.size);
      } else if (can_share_own_pool) {
        /* no downstream pool, use our own then */
        GST_DEBUG_OBJECT (obj->dbg_obj,
            "read/write mode: no downstream pool, using our own");
        pool = gst_object_ref (obj->pool);
        size = obj->info.size;
        pushing_from_our_pool = TRUE;
      }
      break;

    case GST_V4L2_IO_USERPTR:
    case GST_V4L2_IO_DMABUF_IMPORT:
      /* in importing mode, prefer our own pool, and pass the other pool to
       * our own, so it can serve itself */
      if (pool == NULL)
        goto no_downstream_pool;
      gst_v4l2_buffer_pool_set_other_pool (GST_V4L2_BUFFER_POOL (obj->pool),
          pool);
      other_pool = pool;
      gst_object_unref (pool);
      pool = gst_object_ref (obj->pool);
      size = obj->info.size;
      break;

    case GST_V4L2_IO_MMAP:
    case GST_V4L2_IO_DMABUF:
      /* in streaming mode, prefer our own pool */
      /* Check if we can use it ... */
      if (can_share_own_pool) {
        if (pool)
          gst_object_unref (pool);
        pool = gst_object_ref (obj->pool);
        size = obj->info.size;
        GST_DEBUG_OBJECT (obj->dbg_obj,
            "streaming mode: using our own pool %" GST_PTR_FORMAT, pool);
        pushing_from_our_pool = TRUE;
      } else if (pool) {
        GST_DEBUG_OBJECT (obj->dbg_obj,
            "streaming mode: copying to downstream pool %" GST_PTR_FORMAT,
            pool);
      } else {
        GST_DEBUG_OBJECT (obj->dbg_obj,
            "streaming mode: no usable pool, copying to generic pool");
        size = MAX (size, obj->info.size);
      }
      break;
    case GST_V4L2_IO_AUTO:
    default:
      GST_WARNING_OBJECT (obj->dbg_obj, "unhandled mode");
      break;
  }

  if (size == 0)
    goto no_size;

  /* If pushing from our own pool, configure it with queried minimum,
   * otherwise use the minimum required */
  if (pushing_from_our_pool) {
    /* When pushing from our own pool, we need what downstream one, to be able
     * to fill the pipeline, the minimum required to decoder according to the
     * driver and 2 more, so we don't endup up with everything downstream or
     * held by the decoder. We account 2 buffers for v4l2 so when one is being
     * pushed downstream the other one can already be queued for the next
     * frame. */
    own_min = min + obj->min_buffers + 2;

    /* If no allocation parameters where provided, allow for a little more
     * buffers and enable copy threshold */
    if (!update) {
      own_min += 2;
      gst_v4l2_buffer_pool_copy_at_threshold (GST_V4L2_BUFFER_POOL (pool),
          TRUE);
    } else {
      gst_v4l2_buffer_pool_copy_at_threshold (GST_V4L2_BUFFER_POOL (pool),
          FALSE);
    }

  } else {
    /* In this case we'll have to configure two buffer pool. For our buffer
     * pool, we'll need what the driver one, and one more, so we can dequeu */
    own_min = obj->min_buffers + 1;
    own_min = MAX (own_min, GST_V4L2_MIN_BUFFERS (obj));

    /* for the downstream pool, we keep what downstream wants, though ensure
     * at least a minimum if downstream didn't suggest anything (we are
     * expecting the base class to create a default one for the context) */
    min = MAX (min, GST_V4L2_MIN_BUFFERS (obj));

    /* To import we need the other pool to hold at least own_min */
    if (obj->pool == pool)
      min += own_min;

    /* For Xilinx Low Latency mode need to have same buffers in own pool as
       downstream buffers so that no buffer get queued and no buffer slot get
       programmed until downstream has completed previous buffer */
    if (obj->xlnx_ll)
      own_min = min;
  }

  /* Request a bigger max, if one was suggested but it's too small */
  if (max != 0)
    max = MAX (min, max);

  /* First step, configure our own pool */
  config = gst_buffer_pool_get_config (obj->pool);

  if (obj->need_video_meta || has_video_meta) {
    GST_DEBUG_OBJECT (obj->dbg_obj, "activate Video Meta");
    gst_buffer_pool_config_add_option (config,
        GST_BUFFER_POOL_OPTION_VIDEO_META);
  }

  gst_buffer_pool_config_set_allocator (config, allocator, &params);
  gst_buffer_pool_config_set_params (config, caps, size, own_min, 0);

  GST_DEBUG_OBJECT (obj->dbg_obj, "setting own pool config to %"
      GST_PTR_FORMAT, config);

  /* Our pool often need to adjust the value */
  if (!gst_buffer_pool_set_config (obj->pool, config)) {
    config = gst_buffer_pool_get_config (obj->pool);

    GST_DEBUG_OBJECT (obj->dbg_obj, "own pool config changed to %"
        GST_PTR_FORMAT, config);

    /* our pool will adjust the maximum buffer, which we are fine with */
    if (!gst_buffer_pool_set_config (obj->pool, config))
      goto config_failed;
  }

  /* Now configure the other pool if different */
  if (obj->pool != pool)
    other_pool = pool;

  if (other_pool) {
    config = gst_buffer_pool_get_config (other_pool);
    gst_buffer_pool_config_set_allocator (config, allocator, &params);
    gst_buffer_pool_config_set_params (config, caps, size, min, max);

    GST_DEBUG_OBJECT (obj->dbg_obj, "setting other pool config to %"
        GST_PTR_FORMAT, config);

    /* if downstream supports video metadata, add this to the pool config */
    if (has_video_meta) {
      GST_DEBUG_OBJECT (obj->dbg_obj, "activate Video Meta");
      gst_buffer_pool_config_add_option (config,
          GST_BUFFER_POOL_OPTION_VIDEO_META);
    }

    if (!gst_buffer_pool_set_config (other_pool, config)) {
      config = gst_buffer_pool_get_config (other_pool);

      if (!gst_buffer_pool_config_validate_params (config, caps, size, min,
              max)) {
        gst_structure_free (config);
        goto config_failed;
      }

      if (!gst_buffer_pool_set_config (other_pool, config))
        goto config_failed;
    }
  }

  if (pool) {
    /* For simplicity, simply read back the active configuration, so our base
     * class get the right information */
    config = gst_buffer_pool_get_config (pool);
    gst_buffer_pool_config_get_params (config, NULL, &size, &min, &max);
    gst_structure_free (config);
  }

  if (update)
    gst_query_set_nth_allocation_pool (query, 0, pool, size, min, max);
  else
    gst_query_add_allocation_pool (query, pool, size, min, max);

  if (allocator)
    gst_object_unref (allocator);

  if (pool)
    gst_object_unref (pool);

  return TRUE;

pool_failed:
  {
    /* setup_pool already send the error */
    goto cleanup;
  }
config_failed:
  {
    GST_ELEMENT_ERROR (obj->element, RESOURCE, SETTINGS,
        (_("Failed to configure internal buffer pool.")), (NULL));
    goto cleanup;
  }
no_size:
  {
    GST_ELEMENT_ERROR (obj->element, RESOURCE, SETTINGS,
        (_("Video device did not suggest any buffer size.")), (NULL));
    goto cleanup;
  }
cleanup:
  {
    if (allocator)
      gst_object_unref (allocator);

    if (pool)
      gst_object_unref (pool);
    return FALSE;
  }
no_downstream_pool:
  {
    GST_ELEMENT_ERROR (obj->element, RESOURCE, SETTINGS,
        (_("No downstream pool to import from.")),
        ("When importing DMABUF or USERPTR, we need a pool to import from"));
    return FALSE;
  }
}

gboolean
gst_v4l2_object_propose_allocation (GstV4l2Object * obj, GstQuery * query)
{
  GstBufferPool *pool;
  /* we need at least 2 buffers to operate */
  guint size, min, max;
  GstCaps *caps;
  gboolean need_pool;

  /* Set defaults allocation parameters */
  size = obj->info.size;
  min = GST_V4L2_MIN_BUFFERS (obj);
  max = VIDEO_MAX_FRAME;

  gst_query_parse_allocation (query, &caps, &need_pool);

  if (caps == NULL)
    goto no_caps;

  switch (obj->mode) {
    case GST_V4L2_IO_MMAP:
    case GST_V4L2_IO_DMABUF:
      if ((pool = obj->pool))
        gst_object_ref (pool);
      break;
    default:
      pool = NULL;
      break;
  }

  if (pool != NULL) {
    GstCaps *pcaps;
    GstStructure *config;

    /* we had a pool, check caps */
    config = gst_buffer_pool_get_config (pool);
    gst_buffer_pool_config_get_params (config, &pcaps, NULL, NULL, NULL);

    GST_DEBUG_OBJECT (obj->dbg_obj,
        "we had a pool with caps %" GST_PTR_FORMAT, pcaps);
    if (!gst_caps_is_equal (caps, pcaps)) {
      gst_structure_free (config);
      gst_object_unref (pool);
      goto different_caps;
    }
    gst_structure_free (config);
  }
  gst_v4l2_get_driver_min_buffers (obj);

  min = MAX (obj->min_buffers, GST_V4L2_MIN_BUFFERS (obj));

  gst_query_add_allocation_pool (query, pool, size, min, max);

  /* we also support various metadata */
  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, NULL);

  if (pool)
    gst_object_unref (pool);

  return TRUE;

  /* ERRORS */
no_caps:
  {
    GST_DEBUG_OBJECT (obj->dbg_obj, "no caps specified");
    return FALSE;
  }
different_caps:
  {
    /* different caps, we can't use this pool */
    GST_DEBUG_OBJECT (obj->dbg_obj, "pool has different caps");
    return FALSE;
  }
}

gboolean
gst_v4l2_object_try_import (GstV4l2Object * obj, GstBuffer * buffer)
{
  GstVideoMeta *vmeta;
  guint n_mem = gst_buffer_n_memory (buffer);

  /* only import if requested */
  switch (obj->mode) {
    case GST_V4L2_IO_USERPTR:
    case GST_V4L2_IO_DMABUF_IMPORT:
      break;
    default:
      GST_DEBUG_OBJECT (obj->dbg_obj,
          "The io-mode does not enable importation");
      return FALSE;
  }

  vmeta = gst_buffer_get_video_meta (buffer);
  if (!vmeta && obj->need_video_meta) {
    GST_DEBUG_OBJECT (obj->dbg_obj, "Downstream buffer uses standard "
        "stride/offset while the driver does not.");
    return FALSE;
  }

  /* we need matching strides/offsets and size */
  if (vmeta) {
    guint plane_height[GST_VIDEO_MAX_PLANES] = { 0, };

    gst_video_meta_get_plane_height (vmeta, plane_height);

    if (!gst_v4l2_object_match_buffer_layout (obj, vmeta->n_planes,
            vmeta->offset, vmeta->stride, gst_buffer_get_size (buffer),
            plane_height[0]))
      return FALSE;
  }

  /* we can always import single memory buffer, but otherwise we need the same
   * amount of memory object. */
  if (n_mem != 1 && n_mem != obj->n_v4l2_planes) {
    GST_DEBUG_OBJECT (obj->dbg_obj, "Can only import %i memory, "
        "buffers contains %u memory", obj->n_v4l2_planes, n_mem);
    return FALSE;
  }

  /* For DMABuf importation we need DMABuf of course */
  if (obj->mode == GST_V4L2_IO_DMABUF_IMPORT) {
    guint i;

    for (i = 0; i < n_mem; i++) {
      GstMemory *mem = gst_buffer_peek_memory (buffer, i);

      if (!gst_is_dmabuf_memory (mem)) {
        GST_DEBUG_OBJECT (obj->dbg_obj, "Cannot import non-DMABuf memory.");
        return FALSE;
      }
    }
  }

  /* for the remaining, only the kernel driver can tell */
  return TRUE;
}

void
gst_v4l2_object_set_device (GstV4l2Object * v4l2object, const gchar * device)
{
  g_free (v4l2object->videodev);
  v4l2object->videodev = g_strdup (device);
}

gboolean
gst_v4l2_object_get_exclusive_lock (GstV4l2Object * v4l2object)
{
  g_return_val_if_fail (GST_V4L2_IS_OPEN (v4l2object), FALSE);

  return flock (v4l2object->video_fd, LOCK_EX | LOCK_NB) == 0;
}

gboolean
gst_v4l2_object_release_exclusive_lock (GstV4l2Object * v4l2object)
{
  g_return_val_if_fail (GST_V4L2_IS_OPEN (v4l2object), FALSE);

  return flock (v4l2object->video_fd, LOCK_UN | LOCK_NB) == 0;
}
