diff -r 000000000000 -r 6474c204b198 content/media/fmp4/ffmpeg/FFmpegDataDecoder.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/media/fmp4/ffmpeg/FFmpegDataDecoder.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,124 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <string.h>
+#include <unistd.h>
+
+#include "MediaTaskQueue.h"
+#include "mp4_demuxer/mp4_demuxer.h"
+#include "FFmpegRuntimeLinker.h"
+
+#include "FFmpegDataDecoder.h"
+
+namespace mozilla
+{
+
+bool FFmpegDataDecoder::sFFmpegInitDone = false;
+
+FFmpegDataDecoder::FFmpegDataDecoder(MediaTaskQueue* aTaskQueue,
+                                     AVCodecID aCodecID)
+  : mTaskQueue(aTaskQueue), mCodecID(aCodecID)
+{
+  MOZ_COUNT_CTOR(FFmpegDataDecoder);
+}
+
+FFmpegDataDecoder::~FFmpegDataDecoder() {
+  MOZ_COUNT_DTOR(FFmpegDataDecoder);
+}
+
+/**
+ * FFmpeg calls back to this function with a list of pixel formats it supports.
+ * We choose a pixel format that we support and return it.
+ * For now, we just look for YUV420P as it is the only non-HW accelerated format
+ * supported by FFmpeg's H264 decoder.
+ */
+static PixelFormat
+ChoosePixelFormat(AVCodecContext* aCodecContext, const PixelFormat* aFormats)
+{
+  FFMPEG_LOG("Choosing FFmpeg pixel format for video decoding.");
+  for (; *aFormats > -1; aFormats++) {
+    if (*aFormats == PIX_FMT_YUV420P) {
+      FFMPEG_LOG("Requesting pixel format YUV420P.");
+      return PIX_FMT_YUV420P;
+    }
+  }
+
+  NS_WARNING("FFmpeg does not share any supported pixel formats.");
+  return PIX_FMT_NONE;
+}
+
+nsresult
+FFmpegDataDecoder::Init()
+{
+  FFMPEG_LOG("Initialising FFmpeg decoder.");
+
+  if (!FFmpegRuntimeLinker::Link()) {
+    NS_WARNING("Failed to link FFmpeg shared libraries.");
+    return NS_ERROR_FAILURE;
+  }
+
+  if (!sFFmpegInitDone) {
+    av_register_all();
+#ifdef DEBUG
+    av_log_set_level(AV_LOG_DEBUG);
+#endif
+    sFFmpegInitDone = true;
+  }
+
+  AVCodec* codec = avcodec_find_decoder(mCodecID);
+  if (!codec) {
+    NS_WARNING("Couldn't find ffmpeg decoder");
+    return NS_ERROR_FAILURE;
+  }
+
+  if (avcodec_get_context_defaults3(&mCodecContext, codec) < 0) {
+    NS_WARNING("Couldn't init ffmpeg context");
+    return NS_ERROR_FAILURE;
+  }
+
+  mCodecContext.opaque = this;
+
+  // FFmpeg takes this as a suggestion for what format to use for audio samples.
+  mCodecContext.request_sample_fmt = AV_SAMPLE_FMT_FLT;
+
+  // FFmpeg will call back to this to negotiate a video pixel format.
+  mCodecContext.get_format = ChoosePixelFormat;
+
+  AVDictionary* opts = nullptr;
+  if (avcodec_open2(&mCodecContext, codec, &opts) < 0) {
+    NS_WARNING("Couldn't initialise ffmpeg decoder");
+    return NS_ERROR_FAILURE;
+  }
+
+  if (mCodecContext.codec_type == AVMEDIA_TYPE_AUDIO &&
+      mCodecContext.sample_fmt != AV_SAMPLE_FMT_FLT &&
+      mCodecContext.sample_fmt != AV_SAMPLE_FMT_FLTP) {
+    NS_WARNING("FFmpeg AAC decoder outputs unsupported audio format.");
+    return NS_ERROR_FAILURE;
+  }
+
+  FFMPEG_LOG("FFmpeg init successful.");
+  return NS_OK;
+}
+
+nsresult
+FFmpegDataDecoder::Flush()
+{
+  mTaskQueue->Flush();
+  avcodec_flush_buffers(&mCodecContext);
+  return NS_OK;
+}
+
+nsresult
+FFmpegDataDecoder::Shutdown()
+{
+  if (sFFmpegInitDone) {
+    avcodec_close(&mCodecContext);
+  }
+  return NS_OK;
+}
+
+} // namespace mozilla