Merge remote-tracking branch 'qatar/master'

* qatar/master:
  libmp3lame: add missing layout terminator
  avconv: multithreaded demuxing.
  Bump lavu minor and add an APIChanges entry for audioconvert functions.
  audioconvert: add a function for extracting the channel with the given index
  audioconvert: add a function for getting the name of a single channel.
  audioconvert: add a function for getting channel's index in layout
  audioconvert: use av_popcount64 in av_get_channel_layout_nb_channels
  vf_libopencv: add missing headers.
  iac: add missing dependency

Conflicts:
	configure
	doc/APIchanges
	ffmpeg.c
	libavcodec/libmp3lame.c
	libavutil/avutil.h

Merged-by: Michael Niedermayer <michaelni@gmx.at>

3 files changed, 61 insertions, 6 deletions

diff --git a/libavutil/audioconvert.c b/libavutil/audioconvert.c
index 7dc7e9f1a7..e17f52ee59 100644
--- a/libavutil/audioconvert.c
+++ b/libavutil/audioconvert.c
@@ -182,11 +182,7 @@ void av_get_channel_layout_string(char *buf, int buf_size,
 
 int av_get_channel_layout_nb_channels(uint64_t channel_layout)
 {
-    int count;
-    uint64_t x = channel_layout;
-    for (count = 0; x; count++)
-        x &= x-1; // unset lowest set bit
-    return count;
+    return av_popcount64(channel_layout);
 }
 
 int64_t av_get_default_channel_layout(int nb_channels) {
@@ -196,3 +192,38 @@ int64_t av_get_default_channel_layout(int nb_channels) {
             return channel_layout_map[i].layout;
     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);
+}
+
+const char *av_get_channel_name(uint64_t channel)
+{
+    int i;
+    if (av_get_channel_layout_nb_channels(channel) != 1)
+        return NULL;
+    for (i = 0; i < 64; i++)
+        if ((1ULL<<i) & channel)
+            return get_channel_name(i);
+    return NULL;
+}
+
+uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index)
+{
+    int i;
+
+    if (av_get_channel_layout_nb_channels(channel_layout) <= index)
+        return 0;
+
+    for (i = 0; i < 64; i++) {
+        if ((1ULL << i) & channel_layout && !index--)
+            return 1ULL << i;
+    }
+    return 0;
+}
diff --git a/libavutil/audioconvert.h b/libavutil/audioconvert.h
index 319cc8ab71..03e080cb26 100644
--- a/libavutil/audioconvert.h
+++ b/libavutil/audioconvert.h
@@ -150,6 +150,30 @@ int av_get_channel_layout_nb_channels(uint64_t channel_layout);
 int64_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);
+
+/**
+ * Get the channel with the given index in channel_layout.
+ */
+uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index);
+
+/**
+ * Get the name of a given channel.
+ *
+ * @return channel name on success, NULL on error.
+ */
+const char *av_get_channel_name(uint64_t channel);
+
+/**
  * @}
  */
 
diff --git a/libavutil/avutil.h b/libavutil/avutil.h
index 2e83d1fd11..02b9c7b2ed 100644
--- a/libavutil/avutil.h
+++ b/libavutil/avutil.h
@@ -153,7 +153,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR 51
-#define LIBAVUTIL_VERSION_MINOR 56
+#define LIBAVUTIL_VERSION_MINOR 57
 #define LIBAVUTIL_VERSION_MICRO 100
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \