Replace av_malloc with AlignedAlloc for memory allocation in DecoderBuffer.

media/ffmpeg/ffmpeg_common.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_FFMPEG_FFMPEG_COMMON_H_
 #define MEDIA_FFMPEG_FFMPEG_COMMON_H_
 
 // 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"
 
 // Include FFmpeg header files.
 extern "C" {
 // Temporarily disable possible loss of data warning.
 // TODO(scherkus): fix and upstream the compiler warnings.
 MSVC_PUSH_DISABLE_WARNING(4244);
 #include <libavcodec/avcodec.h>
 #include <libavformat/avformat.h>
 #include <libavformat/avio.h>
 #include <libavformat/url.h>
 #include <libavutil/avutil.h>
 #include <libavutil/mathematics.h>
 #include <libavutil/log.h>
 #include <libavutil/imgutils.h>
 MSVC_POP_WARNING();
 }  // extern "C"
 
 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 {
  public:
   inline void operator()(void* x) const {
     av_free(x);
   }
 };
 
 // This assumes that the AVPacket being captured was allocated outside of
@@ skipping 54 matching lines @@
 // Converts an FFmpeg audio codec ID into its corresponding supported codec id.
 AudioCodec CodecIDToAudioCodec(CodecID codec_id);
 
 // Closes & destroys all AVStreams in the context and then closes &
 // destroys the AVFormatContext.
 void DestroyAVFormatContext(AVFormatContext* format_context);
 
 }  // namespace media
 
 #endif  // MEDIA_FFMPEG_FFMPEG_COMMON_H_