Replace av_malloc with AlignedAlloc for memory allocation in VideoFrame.

media/base/video_frame.cc

 // 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.
 
 #include "media/base/video_frame.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/logging.h"
 #include "base/string_piece.h"
 #include "media/base/limits.h"
 #include "media/base/video_util.h"
+
 #if !defined(OS_ANDROID)
-#include "media/ffmpeg/ffmpeg_common.h"
+#include "base/memory/aligned_memory.h"
 #endif
 
 namespace media {
 
 // static
 scoped_refptr<VideoFrame> VideoFrame::CreateFrame(
     VideoFrame::Format format,
     const gfx::Size& coded_size,
     const gfx::Rect& visible_rect,
     const gfx::Size& natural_size,
@@ skipping 119 matching lines @@
 
 static const int kFrameSizeAlignment = 16;
 // Allows faster SIMD YUV convert. Also, FFmpeg overreads/-writes occasionally.
 static const int kFramePadBytes = 15;
 
 // Release data allocated by AllocateRGB() or AllocateYUV().
 static void ReleaseData(uint8* data) {
   DCHECK(data);
   if (data) {
 #if !defined(OS_ANDROID)
-    av_free(data);
+    base::AlignedFree(data);
 #else
     delete[] data;
 #endif
   }
 }
 
 void VideoFrame::AllocateRGB(size_t bytes_per_pixel) {
   // Round up to align at least at a 16-byte boundary for each row.
   // This is sufficient for MMX and SSE2 reads (movq/movdqa).
   size_t bytes_per_row = RoundUp(coded_size_.width(),
                                  kFrameSizeAlignment) * bytes_per_pixel;
   size_t aligned_height = RoundUp(coded_size_.height(), kFrameSizeAlignment);

[xhwang, 2012/12/02 02:13:13]

Why we always need to align height?

[rbultje1, 2012/12/03 19:39:35]

Codecs work in complete 16x16 macroblocks, and decode as such. So a video of
size, say, 2x2 pixels, contains 1 macroblock of 16x16 pixels, so we _need_ to
have a buffer holding at least 16x16 pixels, else we will cause overwrites.

[xhwang, 2012/12/04 01:51:30]

I see, thanks. 

   strides_[VideoFrame::kRGBPlane] = bytes_per_row;
 #if !defined(OS_ANDROID)
   // TODO(dalecurtis): use DataAligned or so, so this #ifdef hackery
   // doesn't need to be repeated in every single user of aligned data.
   data_[VideoFrame::kRGBPlane] = reinterpret_cast<uint8*>(
-      av_malloc(bytes_per_row * aligned_height + kFramePadBytes));
+      base::AlignedAlloc(bytes_per_row * aligned_height + kFramePadBytes,
+                         kAlignmentSize));
 #else
   data_[VideoFrame::kRGBPlane] = new uint8_t[bytes_per_row * aligned_height];
 #endif
   no_longer_needed_cb_ = base::Bind(&ReleaseData, data_[VideoFrame::kRGBPlane]);
   DCHECK(!(reinterpret_cast<intptr_t>(data_[VideoFrame::kRGBPlane]) & 7));
   COMPILE_ASSERT(0 == VideoFrame::kRGBPlane, RGB_data_must_be_index_0);
 }
 
 void VideoFrame::AllocateYUV() {
   DCHECK(format_ == VideoFrame::YV12 || format_ == VideoFrame::YV16);
@@ skipping 12 matching lines @@
                              kFrameSizeAlignment);
   // The *2 here is because some formats (e.g. h264) allow interlaced coding,
   // and then the size needs to be a multiple of two macroblocks (vertically).
   // See libavcodec/utils.c:avcodec_align_dimensions2().
   size_t y_height = RoundUp(coded_size_.height(), kFrameSizeAlignment * 2);
   size_t uv_height = format_ == VideoFrame::YV12 ? y_height / 2 : y_height;
   size_t y_bytes = y_height * y_stride;
   size_t uv_bytes = uv_height * uv_stride;
 
 #if !defined(OS_ANDROID)
   // TODO(dalecurtis): use DataAligned or so, so this #ifdef hackery

[xhwang, 2012/12/02 02:13:13]

I wonder how we can remove #ifdef if for Android we don't use aligned alloc but
otherwise use aligned alloc? Maybe use alligned alloc on all platforms?

[rbultje1, 2012/12/03 19:39:35]

Android doesn't use FFmpeg, so we can't use av_malloc(). If there were a generic
AlignedMalloc class, we could use it. So it's not about aligned alloc, but
rather about the FFmpeg dependency.

[xhwang, 2012/12/04 01:51:30]

base::AlignedAlloc should be available on Android too. Removed #ifdef's.

   // doesn't need to be repeated in every single user of aligned data.
   // The extra line of UV being allocated is because h264 chroma MC
   // overreads by one line in some cases, see libavcodec/utils.c:
   // avcodec_align_dimensions2() and libavcodec/x86/h264_chromamc.asm:
   // put_h264_chroma_mc4_ssse3().
   uint8* data = reinterpret_cast<uint8*>(
-      av_malloc(y_bytes + (uv_bytes * 2 + uv_stride) + kFramePadBytes));
+      base::AlignedAlloc(y_bytes + (uv_bytes * 2 + uv_stride) + kFramePadBytes,
+                         kAlignmentSize));
 #else
   uint8* data = new uint8_t[y_bytes + (uv_bytes * 2)];
 #endif
   no_longer_needed_cb_ = base::Bind(&ReleaseData, data);
   COMPILE_ASSERT(0 == VideoFrame::kYPlane, y_plane_data_must_be_index_0);
   data_[VideoFrame::kYPlane] = data;
   data_[VideoFrame::kUPlane] = data + y_bytes;
   data_[VideoFrame::kVPlane] = data + y_bytes + uv_bytes;
   strides_[VideoFrame::kYPlane] = y_stride;
   strides_[VideoFrame::kUPlane] = uv_stride;
@@ skipping 119 matching lines @@
       break;
     for (int row = 0; row < rows(plane); ++row) {
       base::MD5Update(context, base::StringPiece(
           reinterpret_cast<char*>(data(plane) + stride(plane) * row),
           row_bytes(plane)));
     }
   }
 }
 
 }  // namespace media