avutil/channel_layout: add av_channel_layout_custom_init()

Signed-off-by: Marton Balint <cus@passwd.hu>

1 files changed, 17 insertions, 0 deletions

diff --git a/libavutil/channel_layout.h b/libavutil/channel_layout.h
index 8dc1a91401..dcc320cbfe 100644
--- a/libavutil/channel_layout.h
+++ b/libavutil/channel_layout.h
@@ -618,6 +618,23 @@ void av_channel_description_bprint(struct AVBPrint *bp, enum AVChannel channel_i
 enum AVChannel av_channel_from_string(const char *name);
 
 /**
+ * Initialize a custom channel layout with the specified number of channels.
+ * The channel map will be allocated and the designation of all channels will
+ * be set to AV_CHAN_UNKNOWN.
+ *
+ * This is only a convenience helper function, a custom channel layout can also
+ * be constructed without using this.
+ *
+ * @param channel_layout the layout structure to be initialized
+ * @param nb_channels the number of channels
+ *
+ * @return 0 on success
+ *         AVERROR(EINVAL) if the number of channels <= 0
+ *         AVERROR(ENOMEM) if the channel map could not be allocated
+ */
+int av_channel_layout_custom_init(AVChannelLayout *channel_layout, int nb_channels);
+
+/**
  * Initialize a native channel layout from a bitmask indicating which channels
  * are present.
  *