GstFormat

GstFormat — Dynamically register new data formats

Synopsis

#include <gst/gst.h>

enum                GstFormat;
#define             GST_FORMAT_PERCENT_MAX
#define             GST_FORMAT_PERCENT_SCALE
struct              GstFormatDefinition;
const gchar *       gst_format_get_name                 (GstFormat format);
GQuark              gst_format_to_quark                 (GstFormat format);
GstFormat           gst_format_register                 (const gchar *nick,
                                                         const gchar *description);
GstFormat           gst_format_get_by_nick              (const gchar *nick);
gboolean            gst_formats_contains                (const GstFormat *formats,
                                                         GstFormat format);
const GstFormatDefinition * gst_format_get_details      (GstFormat format);
GstIterator *       gst_format_iterate_definitions      (void);

Description

GstFormats functions are used to register a new format to the gstreamer core. Formats can be used to perform seeking or conversions/query operations.

Details

enum GstFormat

typedef enum {
  GST_FORMAT_UNDEFINED 	=  0, /* must be first in list */
  GST_FORMAT_DEFAULT   	=  1,
  GST_FORMAT_BYTES   	=  2,
  GST_FORMAT_TIME 	=  3,
  GST_FORMAT_BUFFERS =  4,
  GST_FORMAT_PERCENT =  5
} GstFormat;

Standard predefined formats

GST_FORMAT_UNDEFINED

undefined format

GST_FORMAT_DEFAULT

the default format of the pad/element. This can be samples for raw audio, frames/fields for raw video (some, but not all, elements support this; use GST_FORMAT_TIME if you don't have a good reason to query for samples/frames)

GST_FORMAT_BYTES

bytes

GST_FORMAT_TIME

time in nanoseconds

GST_FORMAT_BUFFERS

buffers (few, if any, elements implement this as of May 2009)

GST_FORMAT_PERCENT

percentage of stream (few, if any, elements implement this as of May 2009)

GST_FORMAT_PERCENT_MAX

#define GST_FORMAT_PERCENT_MAX		G_GINT64_CONSTANT (1000000)

The PERCENT format is between 0 and this value


GST_FORMAT_PERCENT_SCALE

#define GST_FORMAT_PERCENT_SCALE G_GINT64_CONSTANT (10000)

The value used to scale down the reported PERCENT format value to its real value.


struct GstFormatDefinition

struct GstFormatDefinition {
  GstFormat    value;
  const gchar *nick;
  const gchar *description;
  GQuark       quark;
};

A format definition

GstFormat value;

The unique id of this format

const gchar *nick;

A short nick of the format

const gchar *description;

A longer description of the format

GQuark quark;

A quark for the nick

gst_format_get_name ()

const gchar *       gst_format_get_name                 (GstFormat format);

Get a printable name for the given format. Do not modify or free.

format :

a GstFormat

Returns :

a reference to the static name of the format or NULL if the format is unknown.

gst_format_to_quark ()

GQuark              gst_format_to_quark                 (GstFormat format);

Get the unique quark for the given format.

format :

a GstFormat

Returns :

the quark associated with the format or 0 if the format is unknown.

gst_format_register ()

GstFormat           gst_format_register                 (const gchar *nick,
                                                         const gchar *description);

Create a new GstFormat based on the nick or return an already registered format with that nick.

nick :

The nick of the new format

description :

The description of the new format

Returns :

A new GstFormat or an already registered format with the same nick. MT safe.

gst_format_get_by_nick ()

GstFormat           gst_format_get_by_nick              (const gchar *nick);

Return the format registered with the given nick.

nick :

The nick of the format

Returns :

The format with nick or GST_FORMAT_UNDEFINED if the format was not registered.

gst_formats_contains ()

gboolean            gst_formats_contains                (const GstFormat *formats,
                                                         GstFormat format);

See if the given format is inside the format array.

formats :

The format array to search

format :

the format to find

Returns :

TRUE if the format is found inside the array

gst_format_get_details ()

const GstFormatDefinition * gst_format_get_details      (GstFormat format);

Get details about the given format.

format :

The format to get details of

Returns :

The GstFormatDefinition for format or NULL on failure. MT safe.

gst_format_iterate_definitions ()

GstIterator *       gst_format_iterate_definitions      (void);

Iterate all the registered formats. The format definition is read only.

Returns :

a GstIterator of GstFormatDefinition. [transfer full]

See Also

GstPad, GstElement