H.264 video codec support using OpenH264/FFmpeg

webrtc/modules/video_coding/codecs/h264/h264_decoder_impl.cc

+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ *
+ */
+
+#include "webrtc/modules/video_coding/codecs/h264/h264_decoder_impl.h"
+
+#include <bitset>
+
+// OpenH264
+#include "codec_api.h"
+#include "codec_app_def.h"
+#include "codec_def.h"
+
+#include "webrtc/base/checks.h"
+#include "webrtc/base/logging.h"
+#include "webrtc/common_video/libyuv/include/webrtc_libyuv.h"
+
+namespace webrtc {
+
+namespace {
+const bool OPENH264_DECODER_LOGGING = false;

[stefan-webrtc, 2015/09/28 11:19:01]

I think it's more common to use kOpenH264DecodeLogging in WebRTC for compile
time constants.

[hbos, 2015/09/30 15:35:18]

Done.

+}  // anonymous namespace

[stefan-webrtc, 2015/09/28 11:19:01]

// namespace

[hbos, 2015/09/30 15:35:18]

Done.

+
+H264DecoderImpl::H264DecoderImpl()
+    : openh264_decoder_(nullptr),
+      decoded_image_(),
+      decoded_image_callback_(nullptr) {
+}
+
+H264DecoderImpl::~H264DecoderImpl() {
+  Release();
+}
+
+int32_t H264DecoderImpl::InitDecode(const VideoCodec* codec_settings,
+                                    int32_t /*number_of_cores*/) {
+  if (codec_settings &&
+      codec_settings->codecType != VideoCodecType::kVideoCodecH264) {
+    return WEBRTC_VIDEO_CODEC_ERR_PARAMETER;
+  }
+
+  int release_ret = Release();
+  if (release_ret != WEBRTC_VIDEO_CODEC_OK)
+    return release_ret;
+  DCHECK(!openh264_decoder_);

[stefan-webrtc, 2015/09/28 11:19:02]

I think you have to rebase since DCHECK is now RTC_DCHECK.

[hbos, 2015/09/30 15:35:18]

Done.

+
+  // Create decoder.
+  if (WelsCreateDecoder(&openh264_decoder_) != 0) {
+    // Failed to create decoder.

[stefan-webrtc, 2015/09/28 11:19:01]

This comment isn't needed since the log below says the same thing.

[hbos, 2015/09/30 15:35:18]

Done.

+    LOG(LS_ERROR) << "Failed to create OpenH264 decoder";
+    DCHECK(!openh264_decoder_);
+    return WEBRTC_VIDEO_CODEC_ERROR;
+  }
+  DCHECK(openh264_decoder_);
+
+  // Initialization parameters.
+  SDecodingParam init_params;
+  memset(&init_params, 0, sizeof(SDecodingParam));
+  init_params.eOutputColorFormat = EVideoFormatType::videoFormatI420;
+  init_params.uiCpuLoad = 0;

[stefan-webrtc, 2015/09/28 11:19:02]

Looks like this is unused by OpenH264, but does it make sense to set it to 0?
cpu load = 0 seems like bad choice.

[hbos, 2015/09/30 15:35:18]

The decoder example on github just clears all the members and then proceeds to
set the desired members, meaning uiCpuLoad is left as 0 by the looks of it. Not
knowing what to set it to I did the same thing (except I listed all the members
and set them explicitly after the initial memset 0, for clarity). Zero may very
well be interpreted as unspecified.
If not we can change this in the future if a later openh264 version gives us
problems.

[stefan-webrtc, 2015/10/01 08:19:30]

SG

+  init_params.uiTargetDqLayer = 0xFF;
+  init_params.eEcActiveIdc = ERROR_CON_IDC::ERROR_CON_DISABLE;
+  init_params.bParseOnly = false;
+  init_params.sVideoProperty.eVideoBsType =
+      VIDEO_BITSTREAM_TYPE::VIDEO_BITSTREAM_DEFAULT;
+
+  // Initialize.
+  if (openh264_decoder_->Initialize(&init_params) != 0) {
+    LOG(LS_ERROR) << "Failed to initialize OpenH264 decoder";
+    Release();
+    return WEBRTC_VIDEO_CODEC_ERROR;
+  }
+  if (OPENH264_DECODER_LOGGING) {
+    int trace_level = WELS_LOG_DETAIL;
+    openh264_decoder_->SetOption(DECODER_OPTION_TRACE_LEVEL,
+                                 &trace_level);
+  }
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+int32_t H264DecoderImpl::Release() {
+  if (openh264_decoder_) {
+    int64_t uninit_ret = openh264_decoder_->Uninitialize();
+    if (uninit_ret != 0) {
+      LOG(LS_WARNING) << "OpenH264 decoder's Uninitialize() returned "
+                      << "unsuccessful: " << uninit_ret;
+    }
+    WelsDestroyDecoder(openh264_decoder_);
+    openh264_decoder_ = nullptr;
+  }
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+int32_t H264DecoderImpl::Reset() {
+  if (!IsInitialized())
+    return WEBRTC_VIDEO_CODEC_UNINITIALIZED;
+  InitDecode(nullptr, 1);
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+int32_t H264DecoderImpl::RegisterDecodeCompleteCallback(
+    DecodedImageCallback* callback) {
+  decoded_image_callback_ = callback;
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+int32_t H264DecoderImpl::Decode(const EncodedImage& input_image,
+                                bool /*missing_frames*/,
+                                const RTPFragmentationHeader* /*fragmentation*/,
+                                const CodecSpecificInfo* codec_specific_info,
+                                int64_t /*render_time_ms*/) {
+  if (!IsInitialized()) {
+    return WEBRTC_VIDEO_CODEC_UNINITIALIZED;
+  }
+  if (!decoded_image_callback_) {
+    LOG(LS_WARNING) << "InitDecode() has been called, but a callback function "
+                    << "has not been set with RegisterDecodeCompleteCallback()";
+    return WEBRTC_VIDEO_CODEC_UNINITIALIZED;
+  }
+  if (!input_image._buffer || !input_image._length)
+    return WEBRTC_VIDEO_CODEC_ERR_PARAMETER;
+  if (codec_specific_info &&
+      codec_specific_info->codecType != VideoCodecType::kVideoCodecH264) {
+    return WEBRTC_VIDEO_CODEC_ERR_PARAMETER;
+  }
+
+  // DecodeFrameNoDelay output.
+  uint8_t* data[3] = { 0, 0, 0 };
+  SBufferInfo buffer_info;
+  memset(&buffer_info, 0, sizeof(SBufferInfo));
+
+  // Decode!
+  DECODING_STATE decode_ret = openh264_decoder_->DecodeFrameNoDelay(
+      input_image._buffer, input_image._length, data, &buffer_info);
+  if (decode_ret != 0) {
+    LOG(LS_ERROR) << "H264 decode failed, returned error bitmask: "
+                  << std::bitset<8>(decode_ret).to_string() << " = "
+                  << decode_ret;
+    if (decode_ret & dsFramePending)
+      LOG(LS_ERROR) << "  dsFramePending";
+    if (decode_ret & dsRefLost)
+      LOG(LS_ERROR) << "  dsRefLost";
+    if (decode_ret & dsBitstreamError)
+      LOG(LS_ERROR) << "  dsBitstreamError";
+    if (decode_ret & dsDepLayerLost)
+      LOG(LS_ERROR) << "  dsDepLayerLost";
+    if (decode_ret & dsNoParamSets)
+      LOG(LS_ERROR) << "  dsNoParamSets";
+    if (decode_ret & dsDataErrorConcealed)
+      LOG(LS_ERROR) << "  dsDataErrorConcealed";
+    return WEBRTC_VIDEO_CODEC_ERROR;
+  }
+  CHECK_EQ(decode_ret, 0);

[stefan-webrtc, 2015/09/28 11:19:01]

Should this be a DCHECK?

[hbos, 2015/09/30 15:35:18]

Done.

+
+  // Frame data ready?
+  if (buffer_info.iBufferStatus == 1) {
+    // Copy decoded data into |decoded_image_|. Must copy because the internal
+    // VideoFrameBuffer is reference counted.
+    decoded_image_.CreateFrame(data[0], data[1], data[2],
+                               buffer_info.UsrData.sSystemBuffer.iWidth,
+                               buffer_info.UsrData.sSystemBuffer.iHeight,
+                               buffer_info.UsrData.sSystemBuffer.iStride[0],
+                               buffer_info.UsrData.sSystemBuffer.iStride[1],
+                               buffer_info.UsrData.sSystemBuffer.iStride[1]);
+    decoded_image_.set_timestamp(input_image._timeStamp);
+    decoded_image_.set_ntp_time_ms(input_image.ntp_time_ms_);
+
+    // Deliver decoded image.
+    decoded_image_callback_->Decoded(decoded_image_);
+  }
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+bool H264DecoderImpl::IsInitialized() {
+  return openh264_decoder_ != nullptr;
+}
+
+}  // namespace webrtc