PDF Surfaces: Cairo: A Vector Graphics Library

## PDF Surfaces PDF Surfaces — Rendering PDF documents |

## Functions

cairo_surface_t * | cairo_pdf_surface_create ()
cairo_surface_t * | cairo_pdf_surface_create_for_stream ()
void | cairo_pdf_surface_restrict_to_version ()
void | cairo_pdf_get_versions ()
const char * | cairo_pdf_version_to_string ()
void | cairo_pdf_surface_set_size ()
int | cairo_pdf_surface_add_outline ()
void | cairo_pdf_surface_set_metadata ()
void | cairo_pdf_surface_set_page_label ()
void | cairo_pdf_surface_set_thumbnail_size ()

## Types and Values

#define | CAIRO_HAS_PDF_SURFACE
#define | CAIRO_PDF_OUTLINE_ROOT
enum | cairo_pdf_outline_flags_t
enum | cairo_pdf_metadata_t
enum | cairo_pdf_version_t

## Description

The PDF surface is used to render cairo graphics to Adobe PDF files and is a multi-page vector surface backend.

The following mime types are supported: `CAIRO_MIME_TYPE_JPEG`, `CAIRO_MIME_TYPE_JP2`, `CAIRO_MIME_TYPE_UNIQUE_ID`, `CAIRO_MIME_TYPE_JBIG2`, `CAIRO_MIME_TYPE_JBIG2_GLOBAL`, `CAIRO_MIME_TYPE_JBIG2_GLOBAL_ID`, `CAIRO_MIME_TYPE_CCITT_FAX`, `CAIRO_MIME_TYPE_CCITT_FAX_PARAMS`.

### JBIG2 Images

JBIG2 data in PDF must be in the embedded format as described in ISO/IEC 11544. Image specific JBIG2 data must be in `CAIRO_MIME_TYPE_JBIG2`. Any global segments in the JBIG2 data (segments with page association field set to 0) must be in `CAIRO_MIME_TYPE_JBIG2_GLOBAL`. The global data may be shared by multiple images. All images sharing the same global data must set `CAIRO_MIME_TYPE_JBIG2_GLOBAL_ID` to a unique identifier. At least one of the images must provide the global data using `CAIRO_MIME_TYPE_JBIG2_GLOBAL`. The global data will only be embedded once and shared by all JBIG2 images with the same `CAIRO_MIME_TYPE_JBIG2_GLOBAL_ID`.

### CCITT Fax Images

The `CAIRO_MIME_TYPE_CCITT_FAX` mime data requires a number of decoding parameters These parameters are specified using `CAIRO_MIME_TYPE_CCITT_FAX_PARAMS`.

`CAIRO_MIME_TYPE_CCITT_FAX_PARAMS` mime data must contain a string of the form "param1=value1 param2=value2 ...".

`Columns` : [required] An integer specifying the width of the image in pixels.

`Rows` : [required] An integer specifying the height of the image in scan lines.

`K` : [optional] An integer identifying the encoding scheme used. < 0 is 2 dimensional Group 4, = 0 is Group3 1 dimensional, > 0 is mixed 1 and 2 dimensional encoding. Default is 0.

`EndOfLine` : [optional] If true end-of-line bit patterns are present. Default is false.

`EncodedByteAlign` : [optional] If true the end of line is padded with 0 bits so the next line begins on a byte boundary. Default is false.

`EndOfBlock` : [optional] If true the data contains an end-of-block pattern. Default is true.

`BlackIs1` : [optional] If true 1 bits are black pixels. Default is false.

`DamagedRowsBeforeError` : [optional] An integer specifying the number of damages rows tolerated before an error occurs. Default is 0.

Boolean values may be "true" or "false", or 1 or 0.

These parameters are the same as the CCITTFaxDecode parameters in the PostScript Language Reference and Portable Document Format (PDF). Refer to these documents for further details.

An example `CAIRO_MIME_TYPE_CCITT_FAX_PARAMS` string is:

    "Columns=10230 Rows=40000 K=1 EndOfLine=true EncodedByteAlign=1 BlackIs1=false"

## Functions

### cairo_pdf_surface_create ()

    cairo_surface_t *
    cairo_pdf_surface_create (const char *filename,
                              double width_in_points,
                              double height_in_points);

Creates a PDF surface of the specified size in points to be written to `filename` .

#### Parameters

filename | a filename for the PDF output (must be writable), `NULL` may be used to specify no output. This will generate a PDF surface that may be queried and used as a source, without generating a temporary file. |
width_in_points | width of the surface, in points (1 point == 1/72.0 inch) |
height_in_points | height of the surface, in points (1 point == 1/72.0 inch) |

#### Returns

a pointer to the newly created surface. The caller owns the surface and should call `cairo_surface_destroy()` when done with it.

This function always returns a valid pointer, but it will return a pointer to a "nil" surface if an error such as out of memory occurs. You can use `cairo_surface_status()` to check for this.

Since: 1.2

### cairo_pdf_surface_create_for_stream ()

    cairo_surface_t *
    cairo_pdf_surface_create_for_stream (cairo_write_func_t write_func,
                                         void *closure,
                                         double width_in_points,
                                         double height_in_points);

Creates a PDF surface of the specified size in points to be written incrementally to the stream represented by `write_func` and `closure` .

#### Parameters

write_func | a cairo_write_func_t to accept the output data, may be `NULL` to indicate a no-op `write_func` . With a no-op `write_func` , the surface may be queried or used as a source without generating any temporary files. |
closure | the closure argument for `write_func` |
width_in_points | width of the surface, in points (1 point == 1/72.0 inch) |
height_in_points | height of the surface, in points (1 point == 1/72.0 inch) |

#### Returns

a pointer to the newly created surface. The caller owns the surface and should call `cairo_surface_destroy()` when done with it.

This function always returns a valid pointer, but it will return a pointer to a "nil" surface if an error such as out of memory occurs. You can use `cairo_surface_status()` to check for this.

Since: 1.2

### cairo_pdf_surface_restrict_to_version ()

    void
    cairo_pdf_surface_restrict_to_version (cairo_surface_t *surface,
                                           cairo_pdf_version_t version);

Restricts the generated PDF file to `version` . See `cairo_pdf_get_versions()` for a list of available version values that can be used here.

This function should only be called before any drawing operations have been performed on the given surface. The simplest way to do this is to call this function immediately after creating the surface.

#### Parameters

surface | a PDF cairo_surface_t |
version | PDF version |

Since: 1.10

### cairo_pdf_get_versions ()

    void
    cairo_pdf_get_versions (cairo_pdf_version_t const **versions,
                            int *num_versions);

Used to retrieve the list of supported versions. See `cairo_pdf_surface_restrict_to_version()`.

#### Parameters

versions | supported version list |
num_versions | list length |

Since: 1.10

### cairo_pdf_version_to_string ()

    const char *
    cairo_pdf_version_to_string (cairo_pdf_version_t version);

Get the string representation of the given `version` id. This function will return `NULL` if `version` isn't valid. See `cairo_pdf_get_versions()` for a way to get the list of valid version ids.

#### Parameters

version | a version id |

#### Returns

the string associated to given version.

Since: 1.10

### cairo_pdf_surface_set_size ()

    void
    cairo_pdf_surface_set_size (cairo_surface_t *surface,
                                double width_in_points,
                                double height_in_points);

Changes the size of a PDF surface for the current (and subsequent) pages.

This function should only be called before any drawing operations have been performed on the current page. The simplest way to do this is to call this function immediately after creating the surface or immediately after completing a page with either `cairo_show_page()` or `cairo_copy_page()`.

#### Parameters

surface | a PDF cairo_surface_t |
width_in_points | new surface width, in points (1 point == 1/72.0 inch) |
height_in_points | new surface height, in points (1 point == 1/72.0 inch) |

Since: 1.2

### cairo_pdf_surface_add_outline ()

    int
    cairo_pdf_surface_add_outline (cairo_surface_t *surface,
                                   int parent_id,
                                   const char *utf8,
                                   const char *link_attribs,
                                   cairo_pdf_outline_flags_t flags);

Add an item to the document outline hierarchy with the name `utf8` that links to the location specified by `link_attribs` . Link attributes have the same keys and values as the Link Tag, excluding the "rect" attribute. The item will be a child of the item with id `parent_id` . Use `CAIRO_PDF_OUTLINE_ROOT` as the parent id of top level items.

#### Parameters

surface | a PDF cairo_surface_t |
parent_id | the id of the parent item or `CAIRO_PDF_OUTLINE_ROOT` if this is a top level item. |
utf8 | the name of the outline |
link_attribs | the link attributes specifying where this outline links to |
flags | outline item flags |

#### Returns

the id for the added item.

Since: 1.16

### cairo_pdf_surface_set_metadata ()

    void
    cairo_pdf_surface_set_metadata (cairo_surface_t *surface,
                                    cairo_pdf_metadata_t metadata,
                                    const char *utf8);

Set document metadata. The `CAIRO_PDF_METADATA_CREATE_DATE` and `CAIRO_PDF_METADATA_MOD_DATE` values must be in ISO-8601 format: YYYY-MM-DDThh:mm:ss. An optional timezone of the form "[+/-]hh:mm" or "Z" for UTC time can be appended. All other metadata values can be any UTF-8 string.

For example:

    1
    2
    cairo_pdf_surface_set_metadata (surface, CAIRO_PDF_METADATA_TITLE, "My Document");
    cairo_pdf_surface_set_metadata (surface, CAIRO_PDF_METADATA_CREATE_DATE, "2015-12-31T23:59+02:00");

#### Parameters

surface | a PDF cairo_surface_t |
metadata | The metadata item to set. |
utf8 | metadata value |

Since: 1.16

### cairo_pdf_surface_set_page_label ()

    void
    cairo_pdf_surface_set_page_label (cairo_surface_t *surface,
                                      const char *utf8);

Set page label for the current page.

#### Parameters

surface | a PDF cairo_surface_t |
utf8 | The page label. |

Since: 1.16

### cairo_pdf_surface_set_thumbnail_size ()

    void
    cairo_pdf_surface_set_thumbnail_size (cairo_surface_t *surface,
                                          int width,
                                          int height);

Set the thumbnail image size for the current and all subsequent pages. Setting a width or height of 0 disables thumbnails for the current and subsequent pages.

#### Parameters

surface | a PDF cairo_surface_t |
width | Thumbnail width. |
height | Thumbnail height |

Since: 1.16

## Types and Values

### CAIRO_HAS_PDF_SURFACE

    #define CAIRO_HAS_PDF_SURFACE 1

Defined if the PDF surface backend is available. This macro can be used to conditionally compile backend-specific code.

Since: 1.2

### CAIRO_PDF_OUTLINE_ROOT

    #define CAIRO_PDF_OUTLINE_ROOT 0

The root outline item in `cairo_pdf_surface_add_outline()`.

Since: 1.16

### enum cairo_pdf_outline_flags_t

cairo_pdf_outline_flags_t is used by the `cairo_pdf_surface_add_outline()` function specify the attributes of an outline item. These flags may be bitwise-or'd to produce any combination of flags.

#### Members

CAIRO_PDF_OUTLINE_FLAG_OPEN | The outline item defaults to open in the PDF viewer (Since 1.16) |
CAIRO_PDF_OUTLINE_FLAG_BOLD | The outline item is displayed by the viewer in bold text (Since 1.16) |
CAIRO_PDF_OUTLINE_FLAG_ITALIC | The outline item is displayed by the viewer in italic text (Since 1.16) |

Since: 1.16

### enum cairo_pdf_metadata_t

cairo_pdf_metadata_t is used by the `cairo_pdf_surface_set_metadata()` function specify the metadata to set.

#### Members

CAIRO_PDF_METADATA_TITLE | The document title (Since 1.16) |
CAIRO_PDF_METADATA_AUTHOR | The document author (Since 1.16) |
CAIRO_PDF_METADATA_SUBJECT | The document subject (Since 1.16) |
CAIRO_PDF_METADATA_KEYWORDS | The document keywords (Since 1.16) |
CAIRO_PDF_METADATA_CREATOR | The document creator (Since 1.16) |
CAIRO_PDF_METADATA_CREATE_DATE | The document creation date (Since 1.16) |
CAIRO_PDF_METADATA_MOD_DATE | The document modification date (Since 1.16) |

Since: 1.16

### enum cairo_pdf_version_t

cairo_pdf_version_t is used to describe the version number of the PDF specification that a generated PDF file will conform to.

#### Members

CAIRO_PDF_VERSION_1_4 | The version 1.4 of the PDF specification. (Since 1.10) |
CAIRO_PDF_VERSION_1_5 | The version 1.5 of the PDF specification. (Since 1.10) |

Since: 1.10

## See Also

cairo_surface_t