|  |  |  | GStreamer Base Plugins 1.0 Library Reference Manual |  | 
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| Top | Description | ||||
#include <gst/audio/gstaudiometa.h> struct GstAudioDownmixMeta; GstAudioDownmixMeta * gst_buffer_add_audio_downmix_meta (GstBuffer *buffer,const GstAudioChannelPosition *from_position,gint from_channels,const GstAudioChannelPosition *to_position,gint to_channels,const gfloat **matrix); #define gst_buffer_get_audio_downmix_meta (b) GstAudioDownmixMeta * gst_buffer_get_audio_downmix_meta_for_channels (GstBuffer *buffer,const GstAudioChannelPosition *to_position,gint to_channels);
struct GstAudioDownmixMeta {
  GstMeta      meta;
  GstAudioChannelPosition *from_position;
  GstAudioChannelPosition *to_position;
  gint        from_channels, to_channels;
  gfloat       **matrix;
};
Extra buffer metadata describing audio downmixing matrix. This metadata is
attached to audio buffers and contains a matrix to downmix the buffer number
of channels to channels.
matrix is an two-dimensional array of to_channels times from_channels
coefficients, i.e. the i-th output channels is constructed by multiplicating
the input channels with the coefficients in matrix[i] and taking the sum
of the results.
| GstMeta  | parent GstMeta | 
| GstAudioChannelPosition * | the channel positions of the source | 
| GstAudioChannelPosition * | the channel positions of the destination | 
| gint  | the number of channels of the source | 
| gint  | the number of channels of the destination | 
| gfloat ** | the matrix coefficients. | 
GstAudioDownmixMeta * gst_buffer_add_audio_downmix_meta (GstBuffer *buffer,const GstAudioChannelPosition *from_position,gint from_channels,const GstAudioChannelPosition *to_position,gint to_channels,const gfloat **matrix);
Attaches GstAudioDownmixMeta metadata to buffer with the given parameters.
matrix is an two-dimensional array of to_channels times from_channels
coefficients, i.e. the i-th output channels is constructed by multiplicating
the input channels with the coefficients in matrix[i] and taking the sum
of the results.
| 
 | a GstBuffer | 
| 
 | the channel positions of the source. [array length=from_channels] | 
| 
 | The number of channels of the source | 
| 
 | the channel positions of the destination. [array length=to_channels] | 
| 
 | The number of channels of the destination | 
| 
 | The matrix coefficients. | 
| Returns : | the GstAudioDownmixMeta on buffer. | 
#define gst_buffer_get_audio_downmix_meta(b) ((GstAudioDownmixMeta*)gst_buffer_get_meta((b),GST_AUDIO_DOWNMIX_META_INFO))
GstAudioDownmixMeta * gst_buffer_get_audio_downmix_meta_for_channels (GstBuffer *buffer,const GstAudioChannelPosition *to_position,gint to_channels);
Find the GstAudioDownmixMeta on buffer for the given destination
channel positions.
| 
 | a GstBuffer | 
| 
 | the channel positions of the destination. [array length=to_channels] | 
| 
 | The number of channels of the destination | 
| Returns : | the GstAudioDownmixMeta on buffer. |