audioconvert: add a function for extracting the channel with the given index

Anton Khirnov committed 14 years ago

Commit 59d58b31 parent 5df320e2 files · +19 −0Browse files

Unified · Split

2 files

libavutil/audioconvert.c +14 −0
libavutil/audioconvert.h +5 −0

libavutil/audioconvert.c+14−0

@@ -213,3 +213,17 @@ const char *av_get_channel_name(uint64_t channel) · 212 unmodified lines
213	213	return get_channel_name(i);
214	214	return NULL;
215	215	}
	216	+
	217	+uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index)
	218	+{
	219	+ int i;
	220	+
	221	+ if (av_get_channel_layout_nb_channels(channel_layout) <= index)
	222	+ return 0;
	223	+
	224	+ for (i = 0; i < 64; i++) {
	225	+ if ((1ULL << i) & channel_layout && !index--)
	226	+ return 1ULL << i;
	227	+ }
	228	+ return 0;
	229	+}

libavutil/audioconvert.h+5−0

@@ -155,6 +155,11 @@ uint64_t av_get_default_channel_layout(int nb_channels); · 154 unmodified lines
155	155	int av_get_channel_layout_channel_index(uint64_t channel_layout,
156	156	uint64_t channel);
157	157
	158	+/**
	159	+ * Get the channel with the given index in channel_layout.
	160	+ */
	161	+uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index);
	162	+
158	163	/**
159	164	* Get the name of a given channel.
160	165	*