video/picture_id_tests.cc - platform/external/webrtc - Gitiles

 /*
  *  Copyright (c) 2013 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 "media/engine/internalencoderfactory.h"
 #include "media/engine/simulcast_encoder_adapter.h"
 #include "modules/rtp_rtcp/source/rtp_format.h"
 #include "modules/video_coding/codecs/vp8/include/vp8.h"
 #include "modules/video_coding/codecs/vp9/include/vp9.h"
 #include "rtc_base/numerics/safe_conversions.h"
 #include "rtc_base/numerics/sequence_number_util.h"
 #include "test/call_test.h"
 #include "test/function_video_encoder_factory.h"

 namespace webrtc {
 namespace {
 const int kFrameMaxWidth = 1280;
 const int kFrameMaxHeight = 720;
 const int kFrameRate = 30;
 const int kMaxSecondsLost = 5;
 const int kMaxFramesLost = kFrameRate * kMaxSecondsLost;
 const int kMinPacketsToObserve = 10;
 const int kEncoderBitrateBps = 300000;
 const uint32_t kPictureIdWraparound = (1 << 15);
 const size_t kNumTemporalLayers[] = {1, 2, 3};

 }  // namespace

 class PictureIdObserver : public test::RtpRtcpObserver {
  public:
   explicit PictureIdObserver(VideoCodecType codec_type)
       : test::RtpRtcpObserver(test::CallTest::kDefaultTimeoutMs),
         codec_type_(codec_type),
         max_expected_picture_id_gap_(0),
         max_expected_tl0_idx_gap_(0),
         num_ssrcs_to_observe_(1) {}

   void SetExpectedSsrcs(size_t num_expected_ssrcs) {
     rtc::CritScope lock(&crit_);
     num_ssrcs_to_observe_ = num_expected_ssrcs;
   }

   void ResetObservedSsrcs() {
     rtc::CritScope lock(&crit_);
     // Do not clear the timestamp and picture_id, to ensure that we check
     // consistency between reinits and recreations.
     num_packets_sent_.clear();
     observed_ssrcs_.clear();
   }

   void SetMaxExpectedPictureIdGap(int max_expected_picture_id_gap) {
     rtc::CritScope lock(&crit_);
     max_expected_picture_id_gap_ = max_expected_picture_id_gap;
     // Expect smaller gap for |tl0_pic_idx| (running index for temporal_idx 0).
     max_expected_tl0_idx_gap_ = max_expected_picture_id_gap_ / 2;
   }

  private:
   struct ParsedPacket {
     uint32_t timestamp;
     uint32_t ssrc;
     int16_t picture_id;
     int16_t tl0_pic_idx;
     uint8_t temporal_idx;
     FrameType frame_type;
   };

   bool ParsePayload(const uint8_t* packet,
                     size_t length,
                     ParsedPacket* parsed) const {
     RTPHeader header;
     EXPECT_TRUE(parser_->Parse(packet, length, &header));
     EXPECT_TRUE(header.ssrc == test::CallTest::kVideoSendSsrcs[0] ||
                 header.ssrc == test::CallTest::kVideoSendSsrcs[1] ||
                 header.ssrc == test::CallTest::kVideoSendSsrcs[2])
         << "Unknown SSRC sent.";

     EXPECT_GE(length, header.headerLength + header.paddingLength);
     size_t payload_length = length - header.headerLength - header.paddingLength;
     if (payload_length == 0) {
       return false;  // Padding packet.
     }

     parsed->timestamp = header.timestamp;
     parsed->ssrc = header.ssrc;

     std::unique_ptr<RtpDepacketizer> depacketizer(
         RtpDepacketizer::Create(codec_type_));
     RtpDepacketizer::ParsedPayload parsed_payload;
     EXPECT_TRUE(depacketizer->Parse(
         &parsed_payload, &packet[header.headerLength], payload_length));

     switch (codec_type_) {
       case kVideoCodecVP8:
         parsed->picture_id = parsed_payload.video_header().vp8().pictureId;
         parsed->tl0_pic_idx = parsed_payload.video_header().vp8().tl0PicIdx;
         parsed->temporal_idx = parsed_payload.video_header().vp8().temporalIdx;
         break;
       case kVideoCodecVP9: {
         const auto& vp9_header = absl::get<RTPVideoHeaderVP9>(
             parsed_payload.video_header().video_type_header);
         parsed->picture_id = vp9_header.picture_id;
         parsed->tl0_pic_idx = vp9_header.tl0_pic_idx;
         parsed->temporal_idx = vp9_header.temporal_idx;
         break;
       }
       default:
         RTC_NOTREACHED();
         break;
     }

     parsed->frame_type = parsed_payload.frame_type;
     return true;
   }

   // Verify continuity and monotonicity of picture_id sequence.
   void VerifyPictureId(const ParsedPacket& current,
                        const ParsedPacket& last) const
       RTC_EXCLUSIVE_LOCKS_REQUIRED(&crit_) {
     if (current.timestamp == last.timestamp) {
       EXPECT_EQ(last.picture_id, current.picture_id);
       return;  // Same frame.
     }

     // Packet belongs to a new frame.
     // Picture id should be increasing.
     EXPECT_TRUE((AheadOf<uint16_t, kPictureIdWraparound>(current.picture_id,
                                                          last.picture_id)));

     // Expect continuously increasing picture id.
     int diff = ForwardDiff<uint16_t, kPictureIdWraparound>(last.picture_id,
                                                            current.picture_id);
     if (diff > 1) {
       // If the VideoSendStream is destroyed, any frames still in queue is lost.
       // Gaps only possible for first frame after a recreation, i.e. key frames.
       EXPECT_EQ(kVideoFrameKey, current.frame_type);
       EXPECT_LE(diff - 1, max_expected_picture_id_gap_);
     }
   }

   void VerifyTl0Idx(const ParsedPacket& current, const ParsedPacket& last) const
       RTC_EXCLUSIVE_LOCKS_REQUIRED(&crit_) {
     if (current.tl0_pic_idx == kNoTl0PicIdx ||
         current.temporal_idx == kNoTemporalIdx) {
       return;  // No temporal layers.
     }

     if (current.timestamp == last.timestamp || current.temporal_idx != 0) {
       EXPECT_EQ(last.tl0_pic_idx, current.tl0_pic_idx);
       return;
     }

     // New frame with |temporal_idx| 0.
     // |tl0_pic_idx| should be increasing.
     EXPECT_TRUE(AheadOf<uint8_t>(current.tl0_pic_idx, last.tl0_pic_idx));

     // Expect continuously increasing idx.
     int diff = ForwardDiff<uint8_t>(last.tl0_pic_idx, current.tl0_pic_idx);
     if (diff > 1) {
       // If the VideoSendStream is destroyed, any frames still in queue is lost.
       // Gaps only possible for first frame after a recreation, i.e. key frames.
       EXPECT_EQ(kVideoFrameKey, current.frame_type);
       EXPECT_LE(diff - 1, max_expected_tl0_idx_gap_);
     }
   }

   Action OnSendRtp(const uint8_t* packet, size_t length) override {
     rtc::CritScope lock(&crit_);

     ParsedPacket parsed;
     if (!ParsePayload(packet, length, &parsed))
       return SEND_PACKET;

     uint32_t ssrc = parsed.ssrc;
     if (last_observed_packet_.find(ssrc) != last_observed_packet_.end()) {
       // Compare to last packet.
       VerifyPictureId(parsed, last_observed_packet_[ssrc]);
       VerifyTl0Idx(parsed, last_observed_packet_[ssrc]);
     }

     last_observed_packet_[ssrc] = parsed;

     // Pass the test when enough media packets have been received on all
     // streams.
     if (++num_packets_sent_[ssrc] >= kMinPacketsToObserve &&
         observed_ssrcs_.find(ssrc) == observed_ssrcs_.end()) {
       observed_ssrcs_.insert(ssrc);
       if (observed_ssrcs_.size() == num_ssrcs_to_observe_) {
         observation_complete_.Set();
       }
     }
     return SEND_PACKET;
   }

   rtc::CriticalSection crit_;
   const VideoCodecType codec_type_;
   std::map<uint32_t, ParsedPacket> last_observed_packet_ RTC_GUARDED_BY(crit_);
   std::map<uint32_t, size_t> num_packets_sent_ RTC_GUARDED_BY(crit_);
   int max_expected_picture_id_gap_ RTC_GUARDED_BY(crit_);
   int max_expected_tl0_idx_gap_ RTC_GUARDED_BY(crit_);
   size_t num_ssrcs_to_observe_ RTC_GUARDED_BY(crit_);
   std::set<uint32_t> observed_ssrcs_ RTC_GUARDED_BY(crit_);
 };

 class PictureIdTest : public test::CallTest,
                       public ::testing::WithParamInterface<size_t> {
  public:
   PictureIdTest() : num_temporal_layers_(GetParam()) {}

   virtual ~PictureIdTest() {
     task_queue_.SendTask([this]() {
       send_transport_.reset();
       receive_transport_.reset();
       DestroyCalls();
     });
   }

   void SetupEncoder(VideoEncoderFactory* encoder_factory,
                     const std::string& payload_name);
   void TestPictureIdContinuousAfterReconfigure(
       const std::vector<int>& ssrc_counts);
   void TestPictureIdIncreaseAfterRecreateStreams(
       const std::vector<int>& ssrc_counts);

  private:
   const size_t num_temporal_layers_;
   std::unique_ptr<PictureIdObserver> observer_;
 };

 INSTANTIATE_TEST_CASE_P(TemporalLayers,
                         PictureIdTest,
                         ::testing::ValuesIn(kNumTemporalLayers));

 // Use a special stream factory to ensure that all simulcast streams are being
 // sent.
 class VideoStreamFactory
     : public VideoEncoderConfig::VideoStreamFactoryInterface {
  public:
   explicit VideoStreamFactory(size_t num_temporal_layers)
       : num_of_temporal_layers_(num_temporal_layers) {}

  private:
   std::vector<VideoStream> CreateEncoderStreams(
       int width,
       int height,
       const VideoEncoderConfig& encoder_config) override {
     std::vector<VideoStream> streams =
         test::CreateVideoStreams(width, height, encoder_config);

     // Use the same total bitrates when sending a single stream to avoid
     // lowering the bitrate estimate and requiring a subsequent rampup.
     const int encoder_stream_bps =
         kEncoderBitrateBps /
         rtc::checked_cast<int>(encoder_config.number_of_streams);

     for (size_t i = 0; i < encoder_config.number_of_streams; ++i) {
       streams[i].min_bitrate_bps = encoder_stream_bps;
       streams[i].target_bitrate_bps = encoder_stream_bps;
       streams[i].max_bitrate_bps = encoder_stream_bps;
       streams[i].num_temporal_layers = num_of_temporal_layers_;
       // test::CreateVideoStreams does not return frame sizes for the lower
       // streams that are accepted by VP8Impl::InitEncode.
       // TODO(brandtr): Fix the problem in test::CreateVideoStreams, rather
       // than overriding the values here.
       streams[i].width =
           width / (1 << (encoder_config.number_of_streams - 1 - i));
       streams[i].height =
           height / (1 << (encoder_config.number_of_streams - 1 - i));
     }

     return streams;
   }

   const size_t num_of_temporal_layers_;
 };

 void PictureIdTest::SetupEncoder(VideoEncoderFactory* encoder_factory,
                                  const std::string& payload_name) {
   observer_.reset(
       new PictureIdObserver(PayloadStringToCodecType(payload_name)));

   task_queue_.SendTask([this, encoder_factory, payload_name]() {
     CreateCalls();

     send_transport_.reset(new test::PacketTransport(
         &task_queue_, sender_call_.get(), observer_.get(),
         test::PacketTransport::kSender, payload_type_map_,
         FakeNetworkPipe::Config()));

     CreateSendConfig(kNumSimulcastStreams, 0, 0, send_transport_.get());
     GetVideoSendConfig()->encoder_settings.encoder_factory = encoder_factory;
     GetVideoSendConfig()->rtp.payload_name = payload_name;
     GetVideoEncoderConfig()->codec_type =
         PayloadStringToCodecType(payload_name);
     GetVideoEncoderConfig()->video_stream_factory =
         new rtc::RefCountedObject<VideoStreamFactory>(num_temporal_layers_);
     GetVideoEncoderConfig()->number_of_streams = 1;
   });
 }

 void PictureIdTest::TestPictureIdContinuousAfterReconfigure(
     const std::vector<int>& ssrc_counts) {
   task_queue_.SendTask([this]() {
     CreateVideoStreams();
     CreateFrameGeneratorCapturer(kFrameRate, kFrameMaxWidth, kFrameMaxHeight);

     // Initial test with a single stream.
     Start();
   });

   EXPECT_TRUE(observer_->Wait()) << "Timed out waiting for packets.";

   // Reconfigure VideoEncoder and test picture id increase.
   // Expect continuously increasing picture id, equivalent to no gaps.
   observer_->SetMaxExpectedPictureIdGap(0);
   for (int ssrc_count : ssrc_counts) {
     GetVideoEncoderConfig()->number_of_streams = ssrc_count;
     observer_->SetExpectedSsrcs(ssrc_count);
     observer_->ResetObservedSsrcs();
     // Make sure the picture_id sequence is continuous on reinit and recreate.
     task_queue_.SendTask([this]() {
       GetVideoSendStream()->ReconfigureVideoEncoder(
           GetVideoEncoderConfig()->Copy());
     });
     EXPECT_TRUE(observer_->Wait()) << "Timed out waiting for packets.";
   }

   task_queue_.SendTask([this]() {
     Stop();
     DestroyStreams();
   });
 }

 void PictureIdTest::TestPictureIdIncreaseAfterRecreateStreams(
     const std::vector<int>& ssrc_counts) {
   task_queue_.SendTask([this]() {
     CreateVideoStreams();
     CreateFrameGeneratorCapturer(kFrameRate, kFrameMaxWidth, kFrameMaxHeight);

     // Initial test with a single stream.
     Start();
   });

   EXPECT_TRUE(observer_->Wait()) << "Timed out waiting for packets.";

   // Recreate VideoSendStream and test picture id increase.
   // When the VideoSendStream is destroyed, any frames still in queue is lost
   // with it, therefore it is expected that some frames might be lost.
   observer_->SetMaxExpectedPictureIdGap(kMaxFramesLost);
   for (int ssrc_count : ssrc_counts) {
     task_queue_.SendTask([this, &ssrc_count]() {
       frame_generator_capturer_->Stop();
       DestroyVideoSendStreams();

       GetVideoEncoderConfig()->number_of_streams = ssrc_count;
       observer_->SetExpectedSsrcs(ssrc_count);
       observer_->ResetObservedSsrcs();

       CreateVideoSendStreams();
       GetVideoSendStream()->Start();
       CreateFrameGeneratorCapturer(kFrameRate, kFrameMaxWidth, kFrameMaxHeight);
       frame_generator_capturer_->Start();
     });

     EXPECT_TRUE(observer_->Wait()) << "Timed out waiting for packets.";
   }

   task_queue_.SendTask([this]() {
     Stop();
     DestroyStreams();
   });
 }

 TEST_P(PictureIdTest, ContinuousAfterReconfigureVp8) {
   test::FunctionVideoEncoderFactory encoder_factory(
       []() { return VP8Encoder::Create(); });
   SetupEncoder(&encoder_factory, "VP8");
   TestPictureIdContinuousAfterReconfigure({1, 3, 3, 1, 1});
 }

 TEST_P(PictureIdTest, IncreasingAfterRecreateStreamVp8) {
   test::FunctionVideoEncoderFactory encoder_factory(
       []() { return VP8Encoder::Create(); });
   SetupEncoder(&encoder_factory, "VP8");
   TestPictureIdIncreaseAfterRecreateStreams({1, 3, 3, 1, 1});
 }

 TEST_P(PictureIdTest, ContinuousAfterStreamCountChangeVp8) {
   test::FunctionVideoEncoderFactory encoder_factory(
       []() { return VP8Encoder::Create(); });
   // Make sure that the picture id is not reset if the stream count goes
   // down and then up.
   SetupEncoder(&encoder_factory, "VP8");
   TestPictureIdContinuousAfterReconfigure({3, 1, 3});
 }

 TEST_P(PictureIdTest, ContinuousAfterReconfigureSimulcastEncoderAdapter) {
   InternalEncoderFactory internal_encoder_factory;
   test::FunctionVideoEncoderFactory encoder_factory(
       [&internal_encoder_factory]() {
         return absl::make_unique<SimulcastEncoderAdapter>(
             &internal_encoder_factory, SdpVideoFormat("VP8"));
       });
   SetupEncoder(&encoder_factory, "VP8");
   TestPictureIdContinuousAfterReconfigure({1, 3, 3, 1, 1});
 }

 TEST_P(PictureIdTest, IncreasingAfterRecreateStreamSimulcastEncoderAdapter) {
   InternalEncoderFactory internal_encoder_factory;
   test::FunctionVideoEncoderFactory encoder_factory(
       [&internal_encoder_factory]() {
         return absl::make_unique<SimulcastEncoderAdapter>(
             &internal_encoder_factory, SdpVideoFormat("VP8"));
       });
   SetupEncoder(&encoder_factory, "VP8");
   TestPictureIdIncreaseAfterRecreateStreams({1, 3, 3, 1, 1});
 }

 TEST_P(PictureIdTest, ContinuousAfterStreamCountChangeSimulcastEncoderAdapter) {
   InternalEncoderFactory internal_encoder_factory;
   test::FunctionVideoEncoderFactory encoder_factory(
       [&internal_encoder_factory]() {
         return absl::make_unique<SimulcastEncoderAdapter>(
             &internal_encoder_factory, SdpVideoFormat("VP8"));
       });
   // Make sure that the picture id is not reset if the stream count goes
   // down and then up.
   SetupEncoder(&encoder_factory, "VP8");
   TestPictureIdContinuousAfterReconfigure({3, 1, 3});
 }

 TEST_P(PictureIdTest, IncreasingAfterRecreateStreamVp9) {
   test::FunctionVideoEncoderFactory encoder_factory(
       []() { return VP9Encoder::Create(); });
   SetupEncoder(&encoder_factory, "VP9");
   TestPictureIdIncreaseAfterRecreateStreams({1, 1});
 }

 }  // namespace webrtc
	/*
	* Copyright (c) 2013 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 "media/engine/internalencoderfactory.h"
	#include "media/engine/simulcast_encoder_adapter.h"
	#include "modules/rtp_rtcp/source/rtp_format.h"
	#include "modules/video_coding/codecs/vp8/include/vp8.h"
	#include "modules/video_coding/codecs/vp9/include/vp9.h"
	#include "rtc_base/numerics/safe_conversions.h"
	#include "rtc_base/numerics/sequence_number_util.h"
	#include "test/call_test.h"
	#include "test/function_video_encoder_factory.h"

	namespace webrtc {
	namespace {
	const int kFrameMaxWidth = 1280;
	const int kFrameMaxHeight = 720;
	const int kFrameRate = 30;
	const int kMaxSecondsLost = 5;
	const int kMaxFramesLost = kFrameRate * kMaxSecondsLost;
	const int kMinPacketsToObserve = 10;
	const int kEncoderBitrateBps = 300000;
	const uint32_t kPictureIdWraparound = (1 << 15);
	const size_t kNumTemporalLayers[] = {1, 2, 3};

	} // namespace

	class PictureIdObserver : public test::RtpRtcpObserver {
	public:
	explicit PictureIdObserver(VideoCodecType codec_type)
	: test::RtpRtcpObserver(test::CallTest::kDefaultTimeoutMs),
	codec_type_(codec_type),
	max_expected_picture_id_gap_(0),
	max_expected_tl0_idx_gap_(0),
	num_ssrcs_to_observe_(1) {}

	void SetExpectedSsrcs(size_t num_expected_ssrcs) {
	rtc::CritScope lock(&crit_);
	num_ssrcs_to_observe_ = num_expected_ssrcs;
	}

	void ResetObservedSsrcs() {
	rtc::CritScope lock(&crit_);
	// Do not clear the timestamp and picture_id, to ensure that we check
	// consistency between reinits and recreations.
	num_packets_sent_.clear();
	observed_ssrcs_.clear();
	}

	void SetMaxExpectedPictureIdGap(int max_expected_picture_id_gap) {
	rtc::CritScope lock(&crit_);
	max_expected_picture_id_gap_ = max_expected_picture_id_gap;
	// Expect smaller gap for \|tl0_pic_idx\| (running index for temporal_idx 0).
	max_expected_tl0_idx_gap_ = max_expected_picture_id_gap_ / 2;
	}

	private:
	struct ParsedPacket {
	uint32_t timestamp;
	uint32_t ssrc;
	int16_t picture_id;
	int16_t tl0_pic_idx;
	uint8_t temporal_idx;
	FrameType frame_type;
	};

	bool ParsePayload(const uint8_t* packet,
	size_t length,
	ParsedPacket* parsed) const {
	RTPHeader header;
	EXPECT_TRUE(parser_->Parse(packet, length, &header));
	EXPECT_TRUE(header.ssrc == test::CallTest::kVideoSendSsrcs[0] \|\|
	header.ssrc == test::CallTest::kVideoSendSsrcs[1] \|\|
	header.ssrc == test::CallTest::kVideoSendSsrcs[2])
	<< "Unknown SSRC sent.";

	EXPECT_GE(length, header.headerLength + header.paddingLength);
	size_t payload_length = length - header.headerLength - header.paddingLength;
	if (payload_length == 0) {
	return false; // Padding packet.
	}

	parsed->timestamp = header.timestamp;
	parsed->ssrc = header.ssrc;

	std::unique_ptr<RtpDepacketizer> depacketizer(
	RtpDepacketizer::Create(codec_type_));
	RtpDepacketizer::ParsedPayload parsed_payload;
	EXPECT_TRUE(depacketizer->Parse(
	&parsed_payload, &packet[header.headerLength], payload_length));

	switch (codec_type_) {
	case kVideoCodecVP8:
	parsed->picture_id = parsed_payload.video_header().vp8().pictureId;
	parsed->tl0_pic_idx = parsed_payload.video_header().vp8().tl0PicIdx;
	parsed->temporal_idx = parsed_payload.video_header().vp8().temporalIdx;
	break;
	case kVideoCodecVP9: {
	const auto& vp9_header = absl::get<RTPVideoHeaderVP9>(
	parsed_payload.video_header().video_type_header);
	parsed->picture_id = vp9_header.picture_id;
	parsed->tl0_pic_idx = vp9_header.tl0_pic_idx;
	parsed->temporal_idx = vp9_header.temporal_idx;
	break;
	}
	default:
	RTC_NOTREACHED();
	break;
	}

	parsed->frame_type = parsed_payload.frame_type;
	return true;
	}

	// Verify continuity and monotonicity of picture_id sequence.
	void VerifyPictureId(const ParsedPacket& current,
	const ParsedPacket& last) const
	RTC_EXCLUSIVE_LOCKS_REQUIRED(&crit_) {
	if (current.timestamp == last.timestamp) {
	EXPECT_EQ(last.picture_id, current.picture_id);
	return; // Same frame.
	}

	// Packet belongs to a new frame.
	// Picture id should be increasing.
	EXPECT_TRUE((AheadOf<uint16_t, kPictureIdWraparound>(current.picture_id,
	last.picture_id)));

	// Expect continuously increasing picture id.
	int diff = ForwardDiff<uint16_t, kPictureIdWraparound>(last.picture_id,
	current.picture_id);
	if (diff > 1) {
	// If the VideoSendStream is destroyed, any frames still in queue is lost.
	// Gaps only possible for first frame after a recreation, i.e. key frames.
	EXPECT_EQ(kVideoFrameKey, current.frame_type);
	EXPECT_LE(diff - 1, max_expected_picture_id_gap_);
	}
	}

	void VerifyTl0Idx(const ParsedPacket& current, const ParsedPacket& last) const
	RTC_EXCLUSIVE_LOCKS_REQUIRED(&crit_) {
	if (current.tl0_pic_idx == kNoTl0PicIdx \|\|
	current.temporal_idx == kNoTemporalIdx) {
	return; // No temporal layers.
	}

	if (current.timestamp == last.timestamp \|\| current.temporal_idx != 0) {
	EXPECT_EQ(last.tl0_pic_idx, current.tl0_pic_idx);
	return;
	}

	// New frame with \|temporal_idx\| 0.
	// \|tl0_pic_idx\| should be increasing.
	EXPECT_TRUE(AheadOf<uint8_t>(current.tl0_pic_idx, last.tl0_pic_idx));

	// Expect continuously increasing idx.
	int diff = ForwardDiff<uint8_t>(last.tl0_pic_idx, current.tl0_pic_idx);
	if (diff > 1) {
	// If the VideoSendStream is destroyed, any frames still in queue is lost.
	// Gaps only possible for first frame after a recreation, i.e. key frames.
	EXPECT_EQ(kVideoFrameKey, current.frame_type);
	EXPECT_LE(diff - 1, max_expected_tl0_idx_gap_);
	}
	}

	Action OnSendRtp(const uint8_t* packet, size_t length) override {
	rtc::CritScope lock(&crit_);

	ParsedPacket parsed;
	if (!ParsePayload(packet, length, &parsed))
	return SEND_PACKET;

	uint32_t ssrc = parsed.ssrc;
	if (last_observed_packet_.find(ssrc) != last_observed_packet_.end()) {
	// Compare to last packet.
	VerifyPictureId(parsed, last_observed_packet_[ssrc]);
	VerifyTl0Idx(parsed, last_observed_packet_[ssrc]);
	}

	last_observed_packet_[ssrc] = parsed;

	// Pass the test when enough media packets have been received on all
	// streams.
	if (++num_packets_sent_[ssrc] >= kMinPacketsToObserve &&
	observed_ssrcs_.find(ssrc) == observed_ssrcs_.end()) {
	observed_ssrcs_.insert(ssrc);
	if (observed_ssrcs_.size() == num_ssrcs_to_observe_) {
	observation_complete_.Set();
	}
	}
	return SEND_PACKET;
	}

	rtc::CriticalSection crit_;
	const VideoCodecType codec_type_;
	std::map<uint32_t, ParsedPacket> last_observed_packet_ RTC_GUARDED_BY(crit_);
	std::map<uint32_t, size_t> num_packets_sent_ RTC_GUARDED_BY(crit_);
	int max_expected_picture_id_gap_ RTC_GUARDED_BY(crit_);
	int max_expected_tl0_idx_gap_ RTC_GUARDED_BY(crit_);
	size_t num_ssrcs_to_observe_ RTC_GUARDED_BY(crit_);
	std::set<uint32_t> observed_ssrcs_ RTC_GUARDED_BY(crit_);
	};

	class PictureIdTest : public test::CallTest,
	public ::testing::WithParamInterface<size_t> {
	public:
	PictureIdTest() : num_temporal_layers_(GetParam()) {}

	virtual ~PictureIdTest() {
	task_queue_.SendTask([this]() {
	send_transport_.reset();
	receive_transport_.reset();
	DestroyCalls();
	});
	}

	void SetupEncoder(VideoEncoderFactory* encoder_factory,
	const std::string& payload_name);
	void TestPictureIdContinuousAfterReconfigure(
	const std::vector<int>& ssrc_counts);
	void TestPictureIdIncreaseAfterRecreateStreams(
	const std::vector<int>& ssrc_counts);

	private:
	const size_t num_temporal_layers_;
	std::unique_ptr<PictureIdObserver> observer_;
	};

	INSTANTIATE_TEST_CASE_P(TemporalLayers,
	PictureIdTest,
	::testing::ValuesIn(kNumTemporalLayers));

	// Use a special stream factory to ensure that all simulcast streams are being
	// sent.
	class VideoStreamFactory
	: public VideoEncoderConfig::VideoStreamFactoryInterface {
	public:
	explicit VideoStreamFactory(size_t num_temporal_layers)
	: num_of_temporal_layers_(num_temporal_layers) {}

	private:
	std::vector<VideoStream> CreateEncoderStreams(
	int width,
	int height,
	const VideoEncoderConfig& encoder_config) override {
	std::vector<VideoStream> streams =
	test::CreateVideoStreams(width, height, encoder_config);

	// Use the same total bitrates when sending a single stream to avoid
	// lowering the bitrate estimate and requiring a subsequent rampup.
	const int encoder_stream_bps =
	kEncoderBitrateBps /
	rtc::checked_cast<int>(encoder_config.number_of_streams);

	for (size_t i = 0; i < encoder_config.number_of_streams; ++i) {
	streams[i].min_bitrate_bps = encoder_stream_bps;
	streams[i].target_bitrate_bps = encoder_stream_bps;
	streams[i].max_bitrate_bps = encoder_stream_bps;
	streams[i].num_temporal_layers = num_of_temporal_layers_;
	// test::CreateVideoStreams does not return frame sizes for the lower
	// streams that are accepted by VP8Impl::InitEncode.
	// TODO(brandtr): Fix the problem in test::CreateVideoStreams, rather
	// than overriding the values here.
	streams[i].width =
	width / (1 << (encoder_config.number_of_streams - 1 - i));
	streams[i].height =
	height / (1 << (encoder_config.number_of_streams - 1 - i));
	}

	return streams;
	}

	const size_t num_of_temporal_layers_;
	};

	void PictureIdTest::SetupEncoder(VideoEncoderFactory* encoder_factory,
	const std::string& payload_name) {
	observer_.reset(
	new PictureIdObserver(PayloadStringToCodecType(payload_name)));

	task_queue_.SendTask([this, encoder_factory, payload_name]() {
	CreateCalls();

	send_transport_.reset(new test::PacketTransport(
	&task_queue_, sender_call_.get(), observer_.get(),
	test::PacketTransport::kSender, payload_type_map_,
	FakeNetworkPipe::Config()));

	CreateSendConfig(kNumSimulcastStreams, 0, 0, send_transport_.get());
	GetVideoSendConfig()->encoder_settings.encoder_factory = encoder_factory;
	GetVideoSendConfig()->rtp.payload_name = payload_name;
	GetVideoEncoderConfig()->codec_type =
	PayloadStringToCodecType(payload_name);
	GetVideoEncoderConfig()->video_stream_factory =
	new rtc::RefCountedObject<VideoStreamFactory>(num_temporal_layers_);
	GetVideoEncoderConfig()->number_of_streams = 1;
	});
	}

	void PictureIdTest::TestPictureIdContinuousAfterReconfigure(
	const std::vector<int>& ssrc_counts) {
	task_queue_.SendTask([this]() {
	CreateVideoStreams();
	CreateFrameGeneratorCapturer(kFrameRate, kFrameMaxWidth, kFrameMaxHeight);

	// Initial test with a single stream.
	Start();
	});

	EXPECT_TRUE(observer_->Wait()) << "Timed out waiting for packets.";

	// Reconfigure VideoEncoder and test picture id increase.
	// Expect continuously increasing picture id, equivalent to no gaps.
	observer_->SetMaxExpectedPictureIdGap(0);
	for (int ssrc_count : ssrc_counts) {
	GetVideoEncoderConfig()->number_of_streams = ssrc_count;
	observer_->SetExpectedSsrcs(ssrc_count);
	observer_->ResetObservedSsrcs();
	// Make sure the picture_id sequence is continuous on reinit and recreate.
	task_queue_.SendTask([this]() {
	GetVideoSendStream()->ReconfigureVideoEncoder(
	GetVideoEncoderConfig()->Copy());
	});
	EXPECT_TRUE(observer_->Wait()) << "Timed out waiting for packets.";
	}

	task_queue_.SendTask([this]() {
	Stop();
	DestroyStreams();
	});
	}

	void PictureIdTest::TestPictureIdIncreaseAfterRecreateStreams(
	const std::vector<int>& ssrc_counts) {
	task_queue_.SendTask([this]() {
	CreateVideoStreams();
	CreateFrameGeneratorCapturer(kFrameRate, kFrameMaxWidth, kFrameMaxHeight);

	// Initial test with a single stream.
	Start();
	});

	EXPECT_TRUE(observer_->Wait()) << "Timed out waiting for packets.";

	// Recreate VideoSendStream and test picture id increase.
	// When the VideoSendStream is destroyed, any frames still in queue is lost
	// with it, therefore it is expected that some frames might be lost.
	observer_->SetMaxExpectedPictureIdGap(kMaxFramesLost);
	for (int ssrc_count : ssrc_counts) {
	task_queue_.SendTask([this, &ssrc_count]() {
	frame_generator_capturer_->Stop();
	DestroyVideoSendStreams();

	GetVideoEncoderConfig()->number_of_streams = ssrc_count;
	observer_->SetExpectedSsrcs(ssrc_count);
	observer_->ResetObservedSsrcs();

	CreateVideoSendStreams();
	GetVideoSendStream()->Start();
	CreateFrameGeneratorCapturer(kFrameRate, kFrameMaxWidth, kFrameMaxHeight);
	frame_generator_capturer_->Start();
	});

	EXPECT_TRUE(observer_->Wait()) << "Timed out waiting for packets.";
	}

	task_queue_.SendTask([this]() {
	Stop();
	DestroyStreams();
	});
	}

	TEST_P(PictureIdTest, ContinuousAfterReconfigureVp8) {
	test::FunctionVideoEncoderFactory encoder_factory(
	[]() { return VP8Encoder::Create(); });
	SetupEncoder(&encoder_factory, "VP8");
	TestPictureIdContinuousAfterReconfigure({1, 3, 3, 1, 1});
	}

	TEST_P(PictureIdTest, IncreasingAfterRecreateStreamVp8) {
	test::FunctionVideoEncoderFactory encoder_factory(
	[]() { return VP8Encoder::Create(); });
	SetupEncoder(&encoder_factory, "VP8");
	TestPictureIdIncreaseAfterRecreateStreams({1, 3, 3, 1, 1});
	}

	TEST_P(PictureIdTest, ContinuousAfterStreamCountChangeVp8) {
	test::FunctionVideoEncoderFactory encoder_factory(
	[]() { return VP8Encoder::Create(); });
	// Make sure that the picture id is not reset if the stream count goes
	// down and then up.
	SetupEncoder(&encoder_factory, "VP8");
	TestPictureIdContinuousAfterReconfigure({3, 1, 3});
	}

	TEST_P(PictureIdTest, ContinuousAfterReconfigureSimulcastEncoderAdapter) {
	InternalEncoderFactory internal_encoder_factory;
	test::FunctionVideoEncoderFactory encoder_factory(
	[&internal_encoder_factory]() {
	return absl::make_unique<SimulcastEncoderAdapter>(
	&internal_encoder_factory, SdpVideoFormat("VP8"));
	});
	SetupEncoder(&encoder_factory, "VP8");
	TestPictureIdContinuousAfterReconfigure({1, 3, 3, 1, 1});
	}

	TEST_P(PictureIdTest, IncreasingAfterRecreateStreamSimulcastEncoderAdapter) {
	InternalEncoderFactory internal_encoder_factory;
	test::FunctionVideoEncoderFactory encoder_factory(
	[&internal_encoder_factory]() {
	return absl::make_unique<SimulcastEncoderAdapter>(
	&internal_encoder_factory, SdpVideoFormat("VP8"));
	});
	SetupEncoder(&encoder_factory, "VP8");
	TestPictureIdIncreaseAfterRecreateStreams({1, 3, 3, 1, 1});
	}

	TEST_P(PictureIdTest, ContinuousAfterStreamCountChangeSimulcastEncoderAdapter) {
	InternalEncoderFactory internal_encoder_factory;
	test::FunctionVideoEncoderFactory encoder_factory(
	[&internal_encoder_factory]() {
	return absl::make_unique<SimulcastEncoderAdapter>(
	&internal_encoder_factory, SdpVideoFormat("VP8"));
	});
	// Make sure that the picture id is not reset if the stream count goes
	// down and then up.
	SetupEncoder(&encoder_factory, "VP8");
	TestPictureIdContinuousAfterReconfigure({3, 1, 3});
	}

	TEST_P(PictureIdTest, IncreasingAfterRecreateStreamVp9) {
	test::FunctionVideoEncoderFactory encoder_factory(
	[]() { return VP9Encoder::Create(); });
	SetupEncoder(&encoder_factory, "VP9");
	TestPictureIdIncreaseAfterRecreateStreams({1, 1});
	}

	} // namespace webrtc