gstreamer/gst-libs/gst/audio/multichannel.h
Wim Taymans dae848818d audio: rework audio caps.
Rework the audio caps similar to the video caps. Remove
width/depth/endianness/signed fields and replace with a simple string
format and media type audio/x-raw.
Create a GstAudioInfo and some helper methods to parse caps.
Remove duplicate code from the ringbuffer and replace with audio info.
Use AudioInfo in the base audio filter class.
Port elements to new API.
2011-08-18 19:15:03 +02:00

119 lines
4.8 KiB
C

/* GStreamer Multichannel-Audio helper functions
* (c) 2004 Ronald Bultje <rbultje@ronald.bitfreak.net>
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __GST_AUDIO_MULTICHANNEL_H__
#define __GST_AUDIO_MULTICHANNEL_H__
#include <gst/gst.h>
#include <gst/audio/audio-enumtypes.h>
G_BEGIN_DECLS
/**
* GstAudioChannelPosition:
* @GST_AUDIO_CHANNEL_POSITION_FRONT_MONO: front mono
* @GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT: front left
* @GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT: front right
* @GST_AUDIO_CHANNEL_POSITION_REAR_CENTER: rear center
* @GST_AUDIO_CHANNEL_POSITION_REAR_LEFT: rear left
* @GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT: rear right
* @GST_AUDIO_CHANNEL_POSITION_LFE: subwoofer
* @GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER: front center
* @GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER: front left of center
* @GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER: front right of center
* @GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT: side left
* @GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT: side right
* @GST_AUDIO_CHANNEL_POSITION_NONE: used for position-less channels, e.g.
* from a sound card that records 1024 channels; mutually exclusive with
* any other channel position
* @GST_AUDIO_CHANNEL_POSITION_INVALID: invalid position
*
* Audio channel positions.
*/
typedef enum {
GST_AUDIO_CHANNEL_POSITION_INVALID = -1,
/* Main front speakers. Mono and left/right are mututally exclusive! */
GST_AUDIO_CHANNEL_POSITION_FRONT_MONO,
GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT,
GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT,
/* rear. Left/right and center are mututally exclusive! */
GST_AUDIO_CHANNEL_POSITION_REAR_CENTER,
GST_AUDIO_CHANNEL_POSITION_REAR_LEFT,
GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT,
/* subwoofer/low-frequency */
GST_AUDIO_CHANNEL_POSITION_LFE,
/* Center front speakers. Center and left/right_of_center cannot be
* used together! */
GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER,
GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER,
GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER,
/* sides */
GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT,
GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT,
/* for multi-channel input and output with more than 8 channels,
* incompatible with all other positions, either all positions
* are defined or all positions are undefined, but can't mix'n'match */
GST_AUDIO_CHANNEL_POSITION_NONE,
/*< private >*/
/* don't use - counter */
GST_AUDIO_CHANNEL_POSITION_NUM
} GstAudioChannelPosition;
/* Retrieves or sets the positions from/to a GstStructure. Only
* works with fixed caps, caller should check for that! Caller
* g_free()s result of the getter. */
GstAudioChannelPosition *
gst_audio_get_channel_positions (GstStructure *str);
void gst_audio_set_channel_positions (GstStructure *str,
const GstAudioChannelPosition *pos);
/* Sets a (non-fixed) list of possible audio channel positions
* on a structure (this requires the "channels" property to
* be fixed!) or on a caps (here, the "channels" property may be
* unfixed and the caps may even contain multiple structures). */
void gst_audio_set_structure_channel_positions_list
(GstStructure *str,
const GstAudioChannelPosition *pos,
gint num_positions);
void gst_audio_set_caps_channel_positions_list
(GstCaps *caps,
const GstAudioChannelPosition *pos,
gint num_positions);
/* Custom fixate function. Elements that implement some sort of
* channel conversion algorhithm should use this function for
* fixating on GstAudioChannelPosition properties. It will take
* care of equal channel positioning (left/right). Caller g_free()s
* the return value. The input properties may be (and are supposed
* to be) unfixed. */
GstAudioChannelPosition *
gst_audio_fixate_channel_positions (GstStructure *str);
gboolean gst_audio_check_channel_positions (const GstAudioChannelPosition * pos, guint channels);
G_END_DECLS
#endif /* __GST_AUDIO_MULTICHANNEL_H__ */