Motown: ffmpeg implementations of framework 'parts'

services/media/framework_ffmpeg/ffmpeg_decoder.cc

+// Copyright 2016 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 "services/media/framework_ffmpeg/ffmpeg_audio_decoder.h"
+#include "services/media/framework_ffmpeg/ffmpeg_decoder.h"
+#include "services/media/framework_ffmpeg/ffmpeg_type_converters.h"
+#include "services/media/framework_ffmpeg/ffmpeg_video_decoder.h"
+
+namespace mojo {
+namespace media {
+
+Result FfmpegDecoder::Create(
+    const StreamType& stream_type,
+    std::shared_ptr<Decoder>* decoder_out) {
+  DCHECK(decoder_out);
+
+  AVCodecContext* av_codec_context = AVCodecContextFromStreamType(stream_type);
+  if (av_codec_context == nullptr) {
+    return Result::kUnsupportedOperation;
+  }
+
+  AVCodec* ffmpeg_decoder = avcodec_find_decoder(av_codec_context->codec_id);
+  if (ffmpeg_decoder == nullptr) {
+    avcodec_free_context(&av_codec_context);
+    return Result::kUnsupportedOperation;
+  }
+
+  int r = avcodec_open2(av_codec_context, ffmpeg_decoder, nullptr);
+  if (r < 0) {
+    avcodec_free_context(&av_codec_context);
+    return Result::kUnknownError;
+  }
+
+  switch (av_codec_context->codec_type) {
+    case AVMEDIA_TYPE_AUDIO:
+      *decoder_out =
+          std::shared_ptr<Decoder>(new FfmpegAudioDecoder(av_codec_context));
+      break;
+    case AVMEDIA_TYPE_VIDEO:
+      *decoder_out =
+          std::shared_ptr<Decoder>(new FfmpegVideoDecoder(av_codec_context));
+      break;
+    default:
+      avcodec_free_context(&av_codec_context);
+      return Result::kUnsupportedOperation;
+  }
+
+  return Result::kOk;
+}
+
+} // namespace media
+} // namespace mojo