GstFormat

GstFormat — Dynamically register new formats

Synopsis


#include <gst/gst.h>


enum        GstFormat;
#define     GST_FORMAT_PERCENT_MAX
#define     GST_FORMAT_PERCENT_SCALE
struct      GstFormatDefinition;
#define     GST_FORMATS_FUNCTION            (type, functionname, ...)
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);
G_CONST_RETURN GstFormatDefinition* gst_format_get_details
                                            (GstFormat format);
G_CONST_RETURN GList* gst_format_get_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, /* samples for audio, frames/fields for video */
  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
`GST_FORMAT_BYTES`	bytes
`GST_FORMAT_TIME`	time in nanoseconds
`GST_FORMAT_BUFFERS`	buffers
`GST_FORMAT_PERCENT`	percentage of stream

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;
  gchar     *nick;
  gchar     *description;
};

A format definition

GstFormat `value`	The unique id of this format
gchar *`nick`	A short nick of the format
gchar *`description`	A longer description of the format

GST_FORMATS_FUNCTION()

#define     GST_FORMATS_FUNCTION(type, functionname, ...)

A convenience function to define a function that returns an array of formats.

`type` :	The type of the first argument of the function
`functionname` :	The name of the function
`...` :	comma separated list of functions closed with 0

gst_format_register ()

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

Create a new GstFormat based on the nick or return an allrady 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.

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 ()

G_CONST_RETURN 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.

gst_format_get_definitions ()

G_CONST_RETURN GList* gst_format_get_definitions
                                            (void);

Get a list of all the registered formats.

Returns :

A GList of GstFormatDefinition.