* @channel_mapping_family: (out): the channel mapping family
* @stream_count: (out): the number of independent streams
* @coupled_count: (out): the number of stereo streams
- * @channel_mapping: (out) (array): the mapping between the streams
+ * @channel_mapping: (out) (array fixed-size=256): the mapping between the streams
*
* Parses Opus caps and fills the different fields with defaults if possible.
*
* @channel_mapping_family: (out): the channel mapping family
* @stream_count: (out): the number of independent streams
* @coupled_count: (out): the number of stereo streams
- * @channel_mapping: (out) (array): the mapping between the streams
+ * @channel_mapping: (out) (array fixed-size=256): the mapping between the streams
* @pre_skip: (out): Pre-skip in 48kHz samples or 0
* @output_gain: (out): Output gain or 0
*