Update padding/alignment constants to match ffmpeg.

media/ffmpeg/ffmpeg_common.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/ffmpeg/ffmpeg_common.h"
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "media/base/decoder_buffer.h"
 #include "media/base/video_util.h"
 
 namespace media {
 
 // Why FF_INPUT_BUFFER_PADDING_SIZE? FFmpeg assumes all input buffers are
 // padded. Check here to ensure FFmpeg only receives data padded to its
 // specifications.
 static_assert(DecoderBuffer::kPaddingSize >= FF_INPUT_BUFFER_PADDING_SIZE,
               "DecoderBuffer padding size does not fit ffmpeg requirement");
 
 // Alignment requirement by FFmpeg for input and output buffers. This need to
-// be updated to match FFmpeg when it changes.
+// be updated to match FFmpeg when it changes. See libavutil/mem.c.
 #if defined(ARCH_CPU_ARM_FAMILY)
 static const int kFFmpegBufferAddressAlignment = 16;
 #else
 static const int kFFmpegBufferAddressAlignment = 32;
 #endif
 
 // Check here to ensure FFmpeg only receives data aligned to its specifications.
 static_assert(
     DecoderBuffer::kAlignmentSize >= kFFmpegBufferAddressAlignment &&
     DecoderBuffer::kAlignmentSize % kFFmpegBufferAddressAlignment == 0,
     "DecoderBuffer alignment size does not fit ffmpeg requirement");
 
-// Allows faster SIMD YUV convert. Also, FFmpeg overreads/-writes occasionally.
-// See video_get_buffer() in libavcodec/utils.c.
-static const int kFFmpegOutputBufferPaddingSize = 16;
-
-static_assert(VideoFrame::kFrameSizePadding >= kFFmpegOutputBufferPaddingSize,
-              "VideoFrame padding size does not fit ffmpeg requirement");
-
 static_assert(
     VideoFrame::kFrameAddressAlignment >= kFFmpegBufferAddressAlignment &&
     VideoFrame::kFrameAddressAlignment % kFFmpegBufferAddressAlignment == 0,
     "VideoFrame frame address alignment does not fit ffmpeg requirement");
 
+static_assert(
+    VideoFrame::kFrameSizeAlignment >= STRIDE_ALIGN &&
+    VideoFrame::kFrameSizeAlignment % STRIDE_ALIGN == 0,
+    "VideoFrame size alignment does not fit ffmpeg requirement");
+
+// Allows faster SIMD YUV convert. Also, FFmpeg overreads/-writes occasionally.
+// See video_get_buffer() and update_frame_pool() in libavcodec/utils.c
+static_assert(VideoFrame::kFrameSizePadding >= FRAME_PADDING,
+              "VideoFrame padding size does not fit ffmpeg requirement");
+
 static const AVRational kMicrosBase = { 1, base::Time::kMicrosecondsPerSecond };
 
 base::TimeDelta ConvertFromTimeBase(const AVRational& time_base,
                                     int64 timestamp) {
   int64 microseconds = av_rescale_q(timestamp, time_base, kMicrosBase);
   return base::TimeDelta::FromMicroseconds(microseconds);
 }
 
 int64 ConvertToTimeBase(const AVRational& time_base,
                         const base::TimeDelta& timestamp) {
@@ skipping 577 matching lines @@
       return false;
 
     *out = parsed_time;
     return true;
   }
 
   return false;
 }
 
 }  // namespace media