Replace av_malloc with AlignedAlloc for memory allocation in DecoderBuffer.

media/ffmpeg/ffmpeg_common.h

Index: media/ffmpeg/ffmpeg_common.h
diff --git a/media/ffmpeg/ffmpeg_common.h b/media/ffmpeg/ffmpeg_common.h
index 01393698af30c3ca01b2d5fb64f9842a8e6faf3c..d5a05f373b9fe4d3a324e346d85e7151e44fdac0 100644
--- a/media/ffmpeg/ffmpeg_common.h
+++ b/media/ffmpeg/ffmpeg_common.h
@@ -8,10 +8,12 @@
 // Used for FFmpeg error codes.
 #include <cerrno>
 
+#include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/time.h"
 #include "media/base/audio_decoder_config.h"
 #include "media/base/channel_layout.h"
+#include "media/base/decoder_buffer.h"

[acolwell GONE FROM CHROMIUM, 2012/09/20 00:16:21]

move this into cc file too.

[xhwang, 2012/09/20 01:43:03]

Done.

 #include "media/base/media_export.h"
 #include "media/base/video_frame.h"
 #include "media/base/video_decoder_config.h"
@@ -37,6 +39,15 @@ namespace media {
 class AudioDecoderConfig;
 class VideoDecoderConfig;
 
+// Why FF_INPUT_BUFFER_PADDING_SIZE?  FFmpeg assumes all input buffers are
+// padded.  Using av_malloc with padding ensures FFmpeg only receives data

[acolwell GONE FROM CHROMIUM, 2012/09/20 00:16:21]

Comment should be updated. We don't use av_malloc anymore right?

[xhwang, 2012/09/20 01:43:03]

Done.

+// padded and aligned to its specifications.
+COMPILE_ASSERT(DecoderBuffer::kPaddingSize >= FF_INPUT_BUFFER_PADDING_SIZE,

[ddorwin, 2012/09/19 23:59:18]

Shouldn't the new constants be multiples (1 or greater) of the FFmpeg values?

Examples:
Is it okay if kPaddingSize is 17?
Is it not okay if kAlignmentSize is 64?

[DaleCurtis, 2012/09/20 00:00:04]

Do this in the cc file instead.

[xhwang, 2012/09/20 01:43:03]

This should be okay. (+dale to be sure.)
This should also be okay. Done.

[xhwang, 2012/09/20 01:43:03]

Done.

+               decoder_buffer_padding_size_does_not_fit_ffmpeg_requirement);
+// Why 32? This is the alignment size required by FFmpeg for input buffers.
+COMPILE_ASSERT(DecoderBuffer::kAlignmentSize == 32,

[xhwang, 2012/09/20 01:43:03]

The alignment should be positive multiple of 32. E.g. 33 won't work.

+               decoder_buffer_alignment_size_does_not_fit_ffmpeg_requirement);
+
 // Wraps FFmpeg's av_free() in a class that can be passed as a template argument
 // to scoped_ptr_malloc.
 class ScopedPtrAVFree {