gstmultichannel

## gstmultichannel gstmultichannel |

## Synopsis

    #include <gst/audio/multichannel.h>

    enum                GstAudioChannelPosition;

## Description

## Details

### enum GstAudioChannelPosition

    typedef enum {
      /* These get negative indices to allow to use
       * the enum values of the normal cases for the
       * bit-mask position */
      GST_AUDIO_CHANNEL_POSITION_NONE = -3,
      GST_AUDIO_CHANNEL_POSITION_MONO = -2,
      GST_AUDIO_CHANNEL_POSITION_INVALID = -1,

      /* Normal cases */
      GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT = 0,
      GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT,
      GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER,
      GST_AUDIO_CHANNEL_POSITION_LFE1,
      GST_AUDIO_CHANNEL_POSITION_REAR_LEFT,
      GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT,
      GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER,
      GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER,
      GST_AUDIO_CHANNEL_POSITION_REAR_CENTER,
      GST_AUDIO_CHANNEL_POSITION_LFE2,
      GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT,
      GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT,
      GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_LEFT,
      GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_RIGHT,
      GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_CENTER,
      GST_AUDIO_CHANNEL_POSITION_TOP_CENTER,
      GST_AUDIO_CHANNEL_POSITION_TOP_REAR_LEFT,
      GST_AUDIO_CHANNEL_POSITION_TOP_REAR_RIGHT,
      GST_AUDIO_CHANNEL_POSITION_TOP_SIDE_LEFT,
      GST_AUDIO_CHANNEL_POSITION_TOP_SIDE_RIGHT,
      GST_AUDIO_CHANNEL_POSITION_TOP_REAR_CENTER,
      GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_CENTER,
      GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_LEFT,
      GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_RIGHT,
      GST_AUDIO_CHANNEL_POSITION_WIDE_LEFT,
      GST_AUDIO_CHANNEL_POSITION_WIDE_RIGHT,
      GST_AUDIO_CHANNEL_POSITION_SURROUND_LEFT,
      GST_AUDIO_CHANNEL_POSITION_SURROUND_RIGHT
    } GstAudioChannelPosition;

Audio channel positions.

These are the channels defined in SMPTE 2036-2-2008 Table 1 for 22.2 audio systems with the Surround and Wide channels from DTS Coherent Acoustics (v.1.3.1) and 10.2 and 7.1 layouts. In the caps the actual channel layout is expressed with a channel count and a channel mask, which describes the existing channels. The positions in the bit mask correspond to the enum values. For negotiation it is allowed to have more bits set in the channel mask than the number of channels to specify the allowed channel positions but this is not allowed in negotiated caps. It is not allowed in any situation other than the one mentioned below to have less bits set in the channel mask than the number of channels.

`GST_AUDIO_CHANNEL_POSITION_MONO` can only be used with a single mono channel that has no direction information and would be mixed into all directional channels. This is expressed in caps by having a single channel and no channel mask.

`GST_AUDIO_CHANNEL_POSITION_NONE` can only be used if all channels have this position. This is expressed in caps by having a channel mask with no bits set.

As another special case it is allowed to have two channels without a channel mask. This implicitely means that this is a stereo stream with a front left and front right channel.

`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_MONO` | Mono without direction; can only be used with 1 channel
`GST_AUDIO_CHANNEL_POSITION_INVALID` | invalid position
`GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT` | Front left
`GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT` | Front right
`GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER` | Front center
`GST_AUDIO_CHANNEL_POSITION_LFE1` | Low-frequency effects 1 (subwoofer)
`GST_AUDIO_CHANNEL_POSITION_REAR_LEFT` | Rear left
`GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT` | Rear right
`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_REAR_CENTER` | Rear center
`GST_AUDIO_CHANNEL_POSITION_LFE2` | Low-frequency effects 2 (subwoofer)
`GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT` | Side left
`GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT` | Side right
`GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_LEFT` | Top front left
`GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_RIGHT` | Top front right
`GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_CENTER` | Top front center
`GST_AUDIO_CHANNEL_POSITION_TOP_CENTER` | Top center
`GST_AUDIO_CHANNEL_POSITION_TOP_REAR_LEFT` | Top rear left
`GST_AUDIO_CHANNEL_POSITION_TOP_REAR_RIGHT` | Top rear right
`GST_AUDIO_CHANNEL_POSITION_TOP_SIDE_LEFT` | Top side right
`GST_AUDIO_CHANNEL_POSITION_TOP_SIDE_RIGHT` | Top rear right
`GST_AUDIO_CHANNEL_POSITION_TOP_REAR_CENTER` | Top rear center
`GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_CENTER` | Bottom front center
`GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_LEFT` | Bottom front left
`GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_RIGHT` | Bottom front right
`GST_AUDIO_CHANNEL_POSITION_WIDE_LEFT` | Wide left (between front left and side left)
`GST_AUDIO_CHANNEL_POSITION_WIDE_RIGHT` | Wide right (between front right and side right)
`GST_AUDIO_CHANNEL_POSITION_SURROUND_LEFT` | Surround left (between rear left and side left)
`GST_AUDIO_CHANNEL_POSITION_SURROUND_RIGHT` | Surround right (between rear right and side right)