Move ChannelLayout into media namespace.

media/base/channel_layout.cc

Index: media/base/channel_layout.cc
diff --git a/media/base/channel_layout.cc b/media/base/channel_layout.cc
index 8bf02ea18ad6c694978ad303c97ca5d3b773f176..e97cb62bef7c44e1647912aac1c404199e4c26c9 100644
--- a/media/base/channel_layout.cc
+++ b/media/base/channel_layout.cc
@@ -4,6 +4,8 @@
 
 #include "media/base/channel_layout.h"
 
+namespace media {
+
 static const int kLayoutToChannels[] = {
     0,   // CHANNEL_LAYOUT_NONE
     0,   // CHANNEL_LAYOUT_UNSUPPORTED
@@ -23,7 +25,13 @@ static const int kLayoutToChannels[] = {
     8,   // CHANNEL_LAYOUT_7POINT1_WIDE
     2};  // CHANNEL_LAYOUT_STEREO_DOWNMIX
 
-const int kChannelOrderings[CHANNEL_LAYOUT_MAX][CHANNELS_MAX] = {
+// The channel orderings for each layout as specified by FFmpeg.  Each value
+// represents the index of each channel in each layout.  Values of -1 mean the
+// channel at that index is not used for that layout.For example, the left side
+// surround sound channel in FFmpeg's 5.1 layout is in the 5th position (because
+// the order is L, R, C, LFE, LS, RS), so
+// kChannelOrderings[CHANNEL_LAYOUT_5POINT1][SIDE_LEFT] = 4;
+static const int kChannelOrderings[CHANNEL_LAYOUT_MAX][CHANNELS_MAX] = {
   // FL | FR | FC | LFE | BL | BR | FLofC | FRofC | BC | SL | SR | StL | StR
 
   // CHANNEL_LAYOUT_NONE
@@ -83,3 +91,9 @@ const int kChannelOrderings[CHANNEL_LAYOUT_MAX][CHANNELS_MAX] = {
 int ChannelLayoutToChannelCount(ChannelLayout layout) {
   return kLayoutToChannels[layout];
 }
+
+int ChannelOrder(ChannelLayout layout, Channels channel) {
+  return kChannelOrderings[layout][channel];

[Ami GONE FROM CHROMIUM, 2012/10/17 03:54:49]

Could
DCHECK_LT(layout, arraysize(kChannelOrderings));
DCHECK_LT(channel, arraysize(kChannelOrderings[0]));
if you wanted.

[DaleCurtis, 2012/10/17 04:22:13]

Done.

+}
+
+}  // namespace media