audioconvert: add a function for getting channel's index in layout

This commit is contained in:
Anton Khirnov 2012-05-28 08:16:40 +02:00
parent 3596de55fc
commit 406b257de9
2 changed files with 22 additions and 0 deletions

View File

@ -192,3 +192,13 @@ uint64_t av_get_default_channel_layout(int nb_channels)
default: return 0;
}
}
int av_get_channel_layout_channel_index(uint64_t channel_layout,
uint64_t channel)
{
if (!(channel_layout & channel) ||
av_get_channel_layout_nb_channels(channel) != 1)
return AVERROR(EINVAL);
channel_layout &= channel - 1;
return av_get_channel_layout_nb_channels(channel_layout);
}

View File

@ -143,6 +143,18 @@ int av_get_channel_layout_nb_channels(uint64_t channel_layout);
*/
uint64_t av_get_default_channel_layout(int nb_channels);
/**
* Get the index of a channel in channel_layout.
*
* @param channel a channel layout describing exactly one channel which must be
* present in channel_layout.
*
* @return index of channel in channel_layout on success, a negative AVERROR
* on error.
*/
int av_get_channel_layout_channel_index(uint64_t channel_layout,
uint64_t channel);
/**
* @}
*/