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)