modules/video_coding/generic_decoder.cc - src - Git at Google

 /*
  *  Copyright (c) 2012 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 "modules/video_coding/generic_decoder.h"

 #include <stddef.h>

 #include <algorithm>
 #include <cmath>
 #include <iterator>
 #include <utility>

 #include "absl/algorithm/container.h"
 #include "absl/types/optional.h"
 #include "api/video/video_timing.h"
 #include "api/video_codecs/video_decoder.h"
 #include "modules/include/module_common_types_public.h"
 #include "modules/video_coding/include/video_error_codes.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/logging.h"
 #include "rtc_base/trace_event.h"
 #include "system_wrappers/include/clock.h"

 namespace webrtc {

 namespace {

 constexpr size_t kDecoderFrameMemoryLength = 10;

 }

 VCMDecodedFrameCallback::VCMDecodedFrameCallback(
     VCMTiming* timing,
     Clock* clock,
     const FieldTrialsView& field_trials)
     : _clock(clock), _timing(timing) {
   ntp_offset_ =
       _clock->CurrentNtpInMilliseconds() - _clock->TimeInMilliseconds();
 }

 VCMDecodedFrameCallback::~VCMDecodedFrameCallback() {}

 void VCMDecodedFrameCallback::SetUserReceiveCallback(
     VCMReceiveCallback* receiveCallback) {
   RTC_DCHECK(construction_thread_.IsCurrent());
   RTC_DCHECK((!_receiveCallback && receiveCallback) ||
              (_receiveCallback && !receiveCallback));
   _receiveCallback = receiveCallback;
 }

 VCMReceiveCallback* VCMDecodedFrameCallback::UserReceiveCallback() {
   // Called on the decode thread via VCMCodecDataBase::GetDecoder.
   // The callback must always have been set before this happens.
   RTC_DCHECK(_receiveCallback);
   return _receiveCallback;
 }

 int32_t VCMDecodedFrameCallback::Decoded(VideoFrame& decodedImage) {
   // This function may be called on the decode TaskQueue, but may also be called
   // on an OS provided queue such as on iOS (see e.g. b/153465112).
   return Decoded(decodedImage, -1);
 }

 int32_t VCMDecodedFrameCallback::Decoded(VideoFrame& decodedImage,
                                          int64_t decode_time_ms) {
   Decoded(decodedImage,
           decode_time_ms >= 0 ? absl::optional<int32_t>(decode_time_ms)
                               : absl::nullopt,
           absl::nullopt);
   return WEBRTC_VIDEO_CODEC_OK;
 }

 std::pair<absl::optional<FrameInfo>, size_t>
 VCMDecodedFrameCallback::FindFrameInfo(uint32_t rtp_timestamp) {
   absl::optional<FrameInfo> frame_info;

   auto it = absl::c_find_if(frame_infos_, [rtp_timestamp](const auto& entry) {
     return entry.rtp_timestamp == rtp_timestamp ||
            IsNewerTimestamp(entry.rtp_timestamp, rtp_timestamp);
   });
   size_t dropped_frames = std::distance(frame_infos_.begin(), it);

   if (it != frame_infos_.end() && it->rtp_timestamp == rtp_timestamp) {
     // Frame was found and should also be removed from the queue.
     frame_info = std::move(*it);
     ++it;
   }

   frame_infos_.erase(frame_infos_.begin(), it);
   return std::make_pair(std::move(frame_info), dropped_frames);
 }

 void VCMDecodedFrameCallback::Decoded(VideoFrame& decodedImage,
                                       absl::optional<int32_t> decode_time_ms,
                                       absl::optional<uint8_t> qp) {
   RTC_DCHECK(_receiveCallback) << "Callback must not be null at this point";
   TRACE_EVENT_INSTANT1("webrtc", "VCMDecodedFrameCallback::Decoded",
                        "timestamp", decodedImage.timestamp());
   // TODO(holmer): We should improve this so that we can handle multiple
   // callbacks from one call to Decode().
   absl::optional<FrameInfo> frame_info;
   int timestamp_map_size = 0;
   int dropped_frames = 0;
   {
     MutexLock lock(&lock_);
     std::tie(frame_info, dropped_frames) =
         FindFrameInfo(decodedImage.timestamp());
     timestamp_map_size = frame_infos_.size();
   }
   if (dropped_frames > 0) {
     _receiveCallback->OnDroppedFrames(dropped_frames);
   }

   if (!frame_info) {
     RTC_LOG(LS_WARNING) << "Too many frames backed up in the decoder, dropping "
                            "frame with timestamp "
                         << decodedImage.timestamp();
     return;
   }

   decodedImage.set_ntp_time_ms(frame_info->ntp_time_ms);
   decodedImage.set_packet_infos(frame_info->packet_infos);
   decodedImage.set_rotation(frame_info->rotation);
   VideoFrame::RenderParameters render_parameters = _timing->RenderParameters();
   if (render_parameters.max_composition_delay_in_frames) {
     // Subtract frames that are in flight.
     render_parameters.max_composition_delay_in_frames =
         std::max(0, *render_parameters.max_composition_delay_in_frames -
                         timestamp_map_size);
   }
   decodedImage.set_render_parameters(render_parameters);

   RTC_DCHECK(frame_info->decode_start);
   const Timestamp now = _clock->CurrentTime();
   const TimeDelta decode_time = decode_time_ms
                                     ? TimeDelta::Millis(*decode_time_ms)
                                     : now - *frame_info->decode_start;
   _timing->StopDecodeTimer(decode_time, now);
   decodedImage.set_processing_time(
       {*frame_info->decode_start, *frame_info->decode_start + decode_time});

   // Report timing information.
   TimingFrameInfo timing_frame_info;
   if (frame_info->timing.flags != VideoSendTiming::kInvalid) {
     int64_t capture_time_ms = decodedImage.ntp_time_ms() - ntp_offset_;
     // Convert remote timestamps to local time from ntp timestamps.
     frame_info->timing.encode_start_ms -= ntp_offset_;
     frame_info->timing.encode_finish_ms -= ntp_offset_;
     frame_info->timing.packetization_finish_ms -= ntp_offset_;
     frame_info->timing.pacer_exit_ms -= ntp_offset_;
     frame_info->timing.network_timestamp_ms -= ntp_offset_;
     frame_info->timing.network2_timestamp_ms -= ntp_offset_;

     int64_t sender_delta_ms = 0;
     if (decodedImage.ntp_time_ms() < 0) {
       // Sender clock is not estimated yet. Make sure that sender times are all
       // negative to indicate that. Yet they still should be relatively correct.
       sender_delta_ms =
           std::max({capture_time_ms, frame_info->timing.encode_start_ms,
                     frame_info->timing.encode_finish_ms,
                     frame_info->timing.packetization_finish_ms,
                     frame_info->timing.pacer_exit_ms,
                     frame_info->timing.network_timestamp_ms,
                     frame_info->timing.network2_timestamp_ms}) +
           1;
     }

     timing_frame_info.capture_time_ms = capture_time_ms - sender_delta_ms;
     timing_frame_info.encode_start_ms =
         frame_info->timing.encode_start_ms - sender_delta_ms;
     timing_frame_info.encode_finish_ms =
         frame_info->timing.encode_finish_ms - sender_delta_ms;
     timing_frame_info.packetization_finish_ms =
         frame_info->timing.packetization_finish_ms - sender_delta_ms;
     timing_frame_info.pacer_exit_ms =
         frame_info->timing.pacer_exit_ms - sender_delta_ms;
     timing_frame_info.network_timestamp_ms =
         frame_info->timing.network_timestamp_ms - sender_delta_ms;
     timing_frame_info.network2_timestamp_ms =
         frame_info->timing.network2_timestamp_ms - sender_delta_ms;
   }

   timing_frame_info.flags = frame_info->timing.flags;
   timing_frame_info.decode_start_ms = frame_info->decode_start->ms();
   timing_frame_info.decode_finish_ms = now.ms();
   timing_frame_info.render_time_ms =
       frame_info->render_time ? frame_info->render_time->ms() : -1;
   timing_frame_info.rtp_timestamp = decodedImage.timestamp();
   timing_frame_info.receive_start_ms = frame_info->timing.receive_start_ms;
   timing_frame_info.receive_finish_ms = frame_info->timing.receive_finish_ms;
   _timing->SetTimingFrameInfo(timing_frame_info);

   decodedImage.set_timestamp_us(
       frame_info->render_time ? frame_info->render_time->us() : -1);
   _receiveCallback->FrameToRender(decodedImage, qp, decode_time,
                                   frame_info->content_type);
 }

 void VCMDecodedFrameCallback::OnDecoderInfoChanged(
     const VideoDecoder::DecoderInfo& decoder_info) {
   _receiveCallback->OnDecoderInfoChanged(decoder_info);
 }

 void VCMDecodedFrameCallback::Map(FrameInfo frameInfo) {
   int dropped_frames = 0;
   {
     MutexLock lock(&lock_);
     int initial_size = frame_infos_.size();
     if (initial_size == kDecoderFrameMemoryLength) {
       frame_infos_.pop_front();
       dropped_frames = 1;
     }
     frame_infos_.push_back(std::move(frameInfo));
     // If no frame is dropped, the new size should be `initial_size` + 1
   }
   if (dropped_frames > 0) {
     _receiveCallback->OnDroppedFrames(dropped_frames);
   }
 }

 void VCMDecodedFrameCallback::ClearTimestampMap() {
   int dropped_frames = 0;
   {
     MutexLock lock(&lock_);
     dropped_frames = frame_infos_.size();
     frame_infos_.clear();
   }
   if (dropped_frames > 0) {
     _receiveCallback->OnDroppedFrames(dropped_frames);
   }
 }

 VCMGenericDecoder::VCMGenericDecoder(VideoDecoder* decoder)
     : _callback(NULL),
       decoder_(decoder),
       _last_keyframe_content_type(VideoContentType::UNSPECIFIED) {
   RTC_DCHECK(decoder_);
 }

 VCMGenericDecoder::~VCMGenericDecoder() {
   decoder_->Release();
 }

 bool VCMGenericDecoder::Configure(const VideoDecoder::Settings& settings) {
   TRACE_EVENT0("webrtc", "VCMGenericDecoder::Configure");

   bool ok = decoder_->Configure(settings);
   decoder_info_ = decoder_->GetDecoderInfo();
   RTC_LOG(LS_INFO) << "Decoder implementation: " << decoder_info_.ToString();
   if (_callback) {
     _callback->OnDecoderInfoChanged(decoder_info_);
   }
   return ok;
 }

 int32_t VCMGenericDecoder::Decode(const VCMEncodedFrame& frame, Timestamp now) {
   TRACE_EVENT1("webrtc", "VCMGenericDecoder::Decode", "timestamp",
                frame.Timestamp());
   FrameInfo frame_info;
   frame_info.rtp_timestamp = frame.Timestamp();
   frame_info.decode_start = now;
   frame_info.render_time =
       frame.RenderTimeMs() >= 0
           ? absl::make_optional(Timestamp::Millis(frame.RenderTimeMs()))
           : absl::nullopt;
   frame_info.rotation = frame.rotation();
   frame_info.timing = frame.video_timing();
   frame_info.ntp_time_ms = frame.EncodedImage().ntp_time_ms_;
   frame_info.packet_infos = frame.PacketInfos();

   // Set correctly only for key frames. Thus, use latest key frame
   // content type. If the corresponding key frame was lost, decode will fail
   // and content type will be ignored.
   if (frame.FrameType() == VideoFrameType::kVideoFrameKey) {
     frame_info.content_type = frame.contentType();
     _last_keyframe_content_type = frame.contentType();
   } else {
     frame_info.content_type = _last_keyframe_content_type;
   }
   _callback->Map(std::move(frame_info));

   int32_t ret = decoder_->Decode(frame.EncodedImage(), frame.MissingFrame(),
                                  frame.RenderTimeMs());
   VideoDecoder::DecoderInfo decoder_info = decoder_->GetDecoderInfo();
   if (decoder_info != decoder_info_) {
     RTC_LOG(LS_INFO) << "Changed decoder implementation to: "
                      << decoder_info.ToString();
     decoder_info_ = decoder_info;
     if (decoder_info.implementation_name.empty()) {
       decoder_info.implementation_name = "unknown";
     }
     _callback->OnDecoderInfoChanged(std::move(decoder_info));
   }
   if (ret < WEBRTC_VIDEO_CODEC_OK) {
     RTC_LOG(LS_WARNING) << "Failed to decode frame with timestamp "
                         << frame.Timestamp() << ", error code: " << ret;
     _callback->ClearTimestampMap();
   } else if (ret == WEBRTC_VIDEO_CODEC_NO_OUTPUT) {
     // No output.
     _callback->ClearTimestampMap();
   }
   return ret;
 }

 int32_t VCMGenericDecoder::RegisterDecodeCompleteCallback(
     VCMDecodedFrameCallback* callback) {
   _callback = callback;
   int32_t ret = decoder_->RegisterDecodeCompleteCallback(callback);
   if (callback && !decoder_info_.implementation_name.empty()) {
     callback->OnDecoderInfoChanged(decoder_info_);
   }
   return ret;
 }

 }  // namespace webrtc
	/*
	* Copyright (c) 2012 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 "modules/video_coding/generic_decoder.h"

	#include <stddef.h>

	#include <algorithm>
	#include <cmath>
	#include <iterator>
	#include <utility>

	#include "absl/algorithm/container.h"
	#include "absl/types/optional.h"
	#include "api/video/video_timing.h"
	#include "api/video_codecs/video_decoder.h"
	#include "modules/include/module_common_types_public.h"
	#include "modules/video_coding/include/video_error_codes.h"
	#include "rtc_base/checks.h"
	#include "rtc_base/logging.h"
	#include "rtc_base/trace_event.h"
	#include "system_wrappers/include/clock.h"

	namespace webrtc {

	namespace {

	constexpr size_t kDecoderFrameMemoryLength = 10;

	}

	VCMDecodedFrameCallback::VCMDecodedFrameCallback(
	VCMTiming* timing,
	Clock* clock,
	const FieldTrialsView& field_trials)
	: _clock(clock), _timing(timing) {
	ntp_offset_ =
	_clock->CurrentNtpInMilliseconds() - _clock->TimeInMilliseconds();
	}

	VCMDecodedFrameCallback::~VCMDecodedFrameCallback() {}

	void VCMDecodedFrameCallback::SetUserReceiveCallback(
	VCMReceiveCallback* receiveCallback) {
	RTC_DCHECK(construction_thread_.IsCurrent());
	RTC_DCHECK((!_receiveCallback && receiveCallback) \|\|
	(_receiveCallback && !receiveCallback));
	_receiveCallback = receiveCallback;
	}

	VCMReceiveCallback* VCMDecodedFrameCallback::UserReceiveCallback() {
	// Called on the decode thread via VCMCodecDataBase::GetDecoder.
	// The callback must always have been set before this happens.
	RTC_DCHECK(_receiveCallback);
	return _receiveCallback;
	}

	int32_t VCMDecodedFrameCallback::Decoded(VideoFrame& decodedImage) {
	// This function may be called on the decode TaskQueue, but may also be called
	// on an OS provided queue such as on iOS (see e.g. b/153465112).
	return Decoded(decodedImage, -1);
	}

	int32_t VCMDecodedFrameCallback::Decoded(VideoFrame& decodedImage,
	int64_t decode_time_ms) {
	Decoded(decodedImage,
	decode_time_ms >= 0 ? absl::optional<int32_t>(decode_time_ms)
	: absl::nullopt,
	absl::nullopt);
	return WEBRTC_VIDEO_CODEC_OK;
	}

	std::pair<absl::optional<FrameInfo>, size_t>
	VCMDecodedFrameCallback::FindFrameInfo(uint32_t rtp_timestamp) {
	absl::optional<FrameInfo> frame_info;

	auto it = absl::c_find_if(frame_infos_, [rtp_timestamp](const auto& entry) {
	return entry.rtp_timestamp == rtp_timestamp \|\|
	IsNewerTimestamp(entry.rtp_timestamp, rtp_timestamp);
	});
	size_t dropped_frames = std::distance(frame_infos_.begin(), it);

	if (it != frame_infos_.end() && it->rtp_timestamp == rtp_timestamp) {
	// Frame was found and should also be removed from the queue.
	frame_info = std::move(*it);
	++it;
	}

	frame_infos_.erase(frame_infos_.begin(), it);
	return std::make_pair(std::move(frame_info), dropped_frames);
	}

	void VCMDecodedFrameCallback::Decoded(VideoFrame& decodedImage,
	absl::optional<int32_t> decode_time_ms,
	absl::optional<uint8_t> qp) {
	RTC_DCHECK(_receiveCallback) << "Callback must not be null at this point";
	TRACE_EVENT_INSTANT1("webrtc", "VCMDecodedFrameCallback::Decoded",
	"timestamp", decodedImage.timestamp());
	// TODO(holmer): We should improve this so that we can handle multiple
	// callbacks from one call to Decode().
	absl::optional<FrameInfo> frame_info;
	int timestamp_map_size = 0;
	int dropped_frames = 0;
	{
	MutexLock lock(&lock_);
	std::tie(frame_info, dropped_frames) =
	FindFrameInfo(decodedImage.timestamp());
	timestamp_map_size = frame_infos_.size();
	}
	if (dropped_frames > 0) {
	_receiveCallback->OnDroppedFrames(dropped_frames);
	}

	if (!frame_info) {
	RTC_LOG(LS_WARNING) << "Too many frames backed up in the decoder, dropping "
	"frame with timestamp "
	<< decodedImage.timestamp();
	return;
	}

	decodedImage.set_ntp_time_ms(frame_info->ntp_time_ms);
	decodedImage.set_packet_infos(frame_info->packet_infos);
	decodedImage.set_rotation(frame_info->rotation);
	VideoFrame::RenderParameters render_parameters = _timing->RenderParameters();
	if (render_parameters.max_composition_delay_in_frames) {
	// Subtract frames that are in flight.
	render_parameters.max_composition_delay_in_frames =
	std::max(0, *render_parameters.max_composition_delay_in_frames -
	timestamp_map_size);
	}
	decodedImage.set_render_parameters(render_parameters);

	RTC_DCHECK(frame_info->decode_start);
	const Timestamp now = _clock->CurrentTime();
	const TimeDelta decode_time = decode_time_ms
	? TimeDelta::Millis(*decode_time_ms)
	: now - *frame_info->decode_start;
	_timing->StopDecodeTimer(decode_time, now);
	decodedImage.set_processing_time(
	{frame_info->decode_start, frame_info->decode_start + decode_time});

	// Report timing information.
	TimingFrameInfo timing_frame_info;
	if (frame_info->timing.flags != VideoSendTiming::kInvalid) {
	int64_t capture_time_ms = decodedImage.ntp_time_ms() - ntp_offset_;
	// Convert remote timestamps to local time from ntp timestamps.
	frame_info->timing.encode_start_ms -= ntp_offset_;
	frame_info->timing.encode_finish_ms -= ntp_offset_;
	frame_info->timing.packetization_finish_ms -= ntp_offset_;
	frame_info->timing.pacer_exit_ms -= ntp_offset_;
	frame_info->timing.network_timestamp_ms -= ntp_offset_;
	frame_info->timing.network2_timestamp_ms -= ntp_offset_;

	int64_t sender_delta_ms = 0;
	if (decodedImage.ntp_time_ms() < 0) {
	// Sender clock is not estimated yet. Make sure that sender times are all
	// negative to indicate that. Yet they still should be relatively correct.
	sender_delta_ms =
	std::max({capture_time_ms, frame_info->timing.encode_start_ms,
	frame_info->timing.encode_finish_ms,
	frame_info->timing.packetization_finish_ms,
	frame_info->timing.pacer_exit_ms,
	frame_info->timing.network_timestamp_ms,
	frame_info->timing.network2_timestamp_ms}) +
	1;
	}

	timing_frame_info.capture_time_ms = capture_time_ms - sender_delta_ms;
	timing_frame_info.encode_start_ms =
	frame_info->timing.encode_start_ms - sender_delta_ms;
	timing_frame_info.encode_finish_ms =
	frame_info->timing.encode_finish_ms - sender_delta_ms;
	timing_frame_info.packetization_finish_ms =
	frame_info->timing.packetization_finish_ms - sender_delta_ms;
	timing_frame_info.pacer_exit_ms =
	frame_info->timing.pacer_exit_ms - sender_delta_ms;
	timing_frame_info.network_timestamp_ms =
	frame_info->timing.network_timestamp_ms - sender_delta_ms;
	timing_frame_info.network2_timestamp_ms =
	frame_info->timing.network2_timestamp_ms - sender_delta_ms;
	}

	timing_frame_info.flags = frame_info->timing.flags;
	timing_frame_info.decode_start_ms = frame_info->decode_start->ms();
	timing_frame_info.decode_finish_ms = now.ms();
	timing_frame_info.render_time_ms =
	frame_info->render_time ? frame_info->render_time->ms() : -1;
	timing_frame_info.rtp_timestamp = decodedImage.timestamp();
	timing_frame_info.receive_start_ms = frame_info->timing.receive_start_ms;
	timing_frame_info.receive_finish_ms = frame_info->timing.receive_finish_ms;
	_timing->SetTimingFrameInfo(timing_frame_info);

	decodedImage.set_timestamp_us(
	frame_info->render_time ? frame_info->render_time->us() : -1);
	_receiveCallback->FrameToRender(decodedImage, qp, decode_time,
	frame_info->content_type);
	}

	void VCMDecodedFrameCallback::OnDecoderInfoChanged(
	const VideoDecoder::DecoderInfo& decoder_info) {
	_receiveCallback->OnDecoderInfoChanged(decoder_info);
	}

	void VCMDecodedFrameCallback::Map(FrameInfo frameInfo) {
	int dropped_frames = 0;
	{
	MutexLock lock(&lock_);
	int initial_size = frame_infos_.size();
	if (initial_size == kDecoderFrameMemoryLength) {
	frame_infos_.pop_front();
	dropped_frames = 1;
	}
	frame_infos_.push_back(std::move(frameInfo));
	// If no frame is dropped, the new size should be `initial_size` + 1
	}
	if (dropped_frames > 0) {
	_receiveCallback->OnDroppedFrames(dropped_frames);
	}
	}

	void VCMDecodedFrameCallback::ClearTimestampMap() {
	int dropped_frames = 0;
	{
	MutexLock lock(&lock_);
	dropped_frames = frame_infos_.size();
	frame_infos_.clear();
	}
	if (dropped_frames > 0) {
	_receiveCallback->OnDroppedFrames(dropped_frames);
	}
	}

	VCMGenericDecoder::VCMGenericDecoder(VideoDecoder* decoder)
	: _callback(NULL),
	decoder_(decoder),
	_last_keyframe_content_type(VideoContentType::UNSPECIFIED) {
	RTC_DCHECK(decoder_);
	}

	VCMGenericDecoder::~VCMGenericDecoder() {
	decoder_->Release();
	}

	bool VCMGenericDecoder::Configure(const VideoDecoder::Settings& settings) {
	TRACE_EVENT0("webrtc", "VCMGenericDecoder::Configure");

	bool ok = decoder_->Configure(settings);
	decoder_info_ = decoder_->GetDecoderInfo();
	RTC_LOG(LS_INFO) << "Decoder implementation: " << decoder_info_.ToString();
	if (_callback) {
	_callback->OnDecoderInfoChanged(decoder_info_);
	}
	return ok;
	}

	int32_t VCMGenericDecoder::Decode(const VCMEncodedFrame& frame, Timestamp now) {
	TRACE_EVENT1("webrtc", "VCMGenericDecoder::Decode", "timestamp",
	frame.Timestamp());
	FrameInfo frame_info;
	frame_info.rtp_timestamp = frame.Timestamp();
	frame_info.decode_start = now;
	frame_info.render_time =
	frame.RenderTimeMs() >= 0
	? absl::make_optional(Timestamp::Millis(frame.RenderTimeMs()))
	: absl::nullopt;
	frame_info.rotation = frame.rotation();
	frame_info.timing = frame.video_timing();
	frame_info.ntp_time_ms = frame.EncodedImage().ntp_time_ms_;
	frame_info.packet_infos = frame.PacketInfos();

	// Set correctly only for key frames. Thus, use latest key frame
	// content type. If the corresponding key frame was lost, decode will fail
	// and content type will be ignored.
	if (frame.FrameType() == VideoFrameType::kVideoFrameKey) {
	frame_info.content_type = frame.contentType();
	_last_keyframe_content_type = frame.contentType();
	} else {
	frame_info.content_type = _last_keyframe_content_type;
	}
	_callback->Map(std::move(frame_info));

	int32_t ret = decoder_->Decode(frame.EncodedImage(), frame.MissingFrame(),
	frame.RenderTimeMs());
	VideoDecoder::DecoderInfo decoder_info = decoder_->GetDecoderInfo();
	if (decoder_info != decoder_info_) {
	RTC_LOG(LS_INFO) << "Changed decoder implementation to: "
	<< decoder_info.ToString();
	decoder_info_ = decoder_info;
	if (decoder_info.implementation_name.empty()) {
	decoder_info.implementation_name = "unknown";
	}
	_callback->OnDecoderInfoChanged(std::move(decoder_info));
	}
	if (ret < WEBRTC_VIDEO_CODEC_OK) {
	RTC_LOG(LS_WARNING) << "Failed to decode frame with timestamp "
	<< frame.Timestamp() << ", error code: " << ret;
	_callback->ClearTimestampMap();
	} else if (ret == WEBRTC_VIDEO_CODEC_NO_OUTPUT) {
	// No output.
	_callback->ClearTimestampMap();
	}
	return ret;
	}

	int32_t VCMGenericDecoder::RegisterDecodeCompleteCallback(
	VCMDecodedFrameCallback* callback) {
	_callback = callback;
	int32_t ret = decoder_->RegisterDecodeCompleteCallback(callback);
	if (callback && !decoder_info_.implementation_name.empty()) {
	callback->OnDecoderInfoChanged(decoder_info_);
	}
	return ret;
	}

	} // namespace webrtc