gst/gstformat.h

/* GStreamer
 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
 *                    2000 Wim Taymans <wim.taymans@chello.be>
 *
 * gstformat.h: Header for GstFormat types used in queries and
 *              seeking.
 *
 * 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.
 */


#ifndef __GST_FORMAT_H__
#define __GST_FORMAT_H__

#include <glib.h>

#include <gst/gstiterator.h>

G_BEGIN_DECLS

/**
 * GstFormat:
 * @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)
 *
 * Standard predefined formats
 */
/* NOTE: don't forget to update the table in gstformat.c when changing
 * this enum */
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;

/* a percentage is always relative to 1000000 */
/**
 * GST_FORMAT_PERCENT_MAX:
 *
 * The PERCENT format is between 0 and this value
 */
#define GST_FORMAT_PERCENT_MAX          G_GINT64_CONSTANT (1000000)
/**
 * GST_FORMAT_PERCENT_SCALE:
 *
 * The value used to scale down the reported PERCENT format value to
 * its real value.
 */
#define GST_FORMAT_PERCENT_SCALE        G_GINT64_CONSTANT (10000)

typedef struct _GstFormatDefinition GstFormatDefinition;

/**
 * GstFormatDefinition:
 * @value: The unique id of this format
 * @nick: A short nick of the format
 * @description: A longer description of the format
 * @quark: A quark for the nick
 *
 * A format definition
 */
struct _GstFormatDefinition
{
  GstFormat    value;
  const gchar *nick;
  const gchar *description;
  GQuark       quark;
};

GST_API
const gchar*    gst_format_get_name             (GstFormat format);

GST_API
GQuark          gst_format_to_quark             (GstFormat format);

/* register a new format */

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

GST_API
GstFormat       gst_format_get_by_nick          (const gchar *nick);

/* check if a format is in an array of formats */

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

/* query for format details */

GST_API
const GstFormatDefinition*
                gst_format_get_details          (GstFormat format);

GST_API
GstIterator*    gst_format_iterate_definitions  (void);

G_END_DECLS

#endif /* __GST_FORMAT_H__ */