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/*
* Copyright (c) 2018 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 <string>
#include "api/test/video/function_video_encoder_factory.h"
#include "media/engine/internal_encoder_factory.h"
#include "modules/video_coding/codecs/h264/include/h264.h"
#include "modules/video_coding/codecs/vp8/include/vp8.h"
#include "modules/video_coding/codecs/vp9/include/vp9.h"
#include "rtc_base/experiments/encoder_info_settings.h"
#include "test/call_test.h"
#include "test/field_trial.h"
#include "test/frame_generator_capturer.h"
#include "test/video_test_constants.h"
#include "video/config/encoder_stream_factory.h"
namespace webrtc {
namespace {
constexpr int kInitialWidth = 1280;
constexpr int kInitialHeight = 720;
constexpr int kLowStartBps = 100000;
constexpr int kHighStartBps = 1000000;
constexpr int kDefaultVgaMinStartBps = 500000; // From video_stream_encoder.cc
constexpr TimeDelta kTimeout =
TimeDelta::Seconds(10); // Some tests are expected to time out.
void SetEncoderSpecific(VideoEncoderConfig* encoder_config,
VideoCodecType type,
bool automatic_resize,
size_t num_spatial_layers) {
if (type == kVideoCodecVP8) {
VideoCodecVP8 vp8 = VideoEncoder::GetDefaultVp8Settings();
vp8.automaticResizeOn = automatic_resize;
encoder_config->encoder_specific_settings =
rtc::make_ref_counted<VideoEncoderConfig::Vp8EncoderSpecificSettings>(
vp8);
} else if (type == kVideoCodecVP9) {
VideoCodecVP9 vp9 = VideoEncoder::GetDefaultVp9Settings();
vp9.automaticResizeOn = automatic_resize;
vp9.numberOfSpatialLayers = num_spatial_layers;
encoder_config->encoder_specific_settings =
rtc::make_ref_counted<VideoEncoderConfig::Vp9EncoderSpecificSettings>(
vp9);
}
}
} // namespace
class QualityScalingTest : public test::CallTest {
protected:
const std::string kPrefix = "WebRTC-Video-QualityScaling/Enabled-";
const std::string kEnd = ",0,0,0.9995,0.9999,1/";
const absl::optional<VideoEncoder::ResolutionBitrateLimits>
kSinglecastLimits720pVp8 =
EncoderInfoSettings::GetDefaultSinglecastBitrateLimitsForResolution(
kVideoCodecVP8,
1280 * 720);
const absl::optional<VideoEncoder::ResolutionBitrateLimits>
kSinglecastLimits360pVp9 =
EncoderInfoSettings::GetDefaultSinglecastBitrateLimitsForResolution(
kVideoCodecVP9,
640 * 360);
const absl::optional<VideoEncoder::ResolutionBitrateLimits>
kSinglecastLimits720pVp9 =
EncoderInfoSettings::GetDefaultSinglecastBitrateLimitsForResolution(
kVideoCodecVP9,
1280 * 720);
};
class ScalingObserver : public test::SendTest {
protected:
struct TestParams {
bool active;
absl::optional<ScalabilityMode> scalability_mode;
};
ScalingObserver(const std::string& payload_name,
const std::vector<TestParams>& test_params,
int start_bps,
bool automatic_resize,
bool expect_scaling)
: SendTest(expect_scaling ? kTimeout * 4 : kTimeout),
encoder_factory_(
[](const Environment& env,
const SdpVideoFormat& format) -> std::unique_ptr<VideoEncoder> {
if (format.name == "VP8")
return CreateVp8Encoder(env);
if (format.name == "VP9")
return CreateVp9Encoder(env);
if (format.name == "H264")
return CreateH264Encoder(env);
RTC_DCHECK_NOTREACHED() << format.name;
return nullptr;
}),
payload_name_(payload_name),
test_params_(test_params),
start_bps_(start_bps),
automatic_resize_(automatic_resize),
expect_scaling_(expect_scaling) {}
DegradationPreference degradation_preference_ =
DegradationPreference::MAINTAIN_FRAMERATE;
private:
void ModifySenderBitrateConfig(BitrateConstraints* bitrate_config) override {
bitrate_config->start_bitrate_bps = start_bps_;
}
void ModifyVideoDegradationPreference(
DegradationPreference* degradation_preference) override {
*degradation_preference = degradation_preference_;
}
size_t GetNumVideoStreams() const override {
return (payload_name_ == "VP9") ? 1 : test_params_.size();
}
void ModifyVideoConfigs(
VideoSendStream::Config* send_config,
std::vector<VideoReceiveStreamInterface::Config>* receive_configs,
VideoEncoderConfig* encoder_config) override {
send_config->encoder_settings.encoder_factory = &encoder_factory_;
send_config->rtp.payload_name = payload_name_;
send_config->rtp.payload_type =
test::VideoTestConstants::kVideoSendPayloadType;
encoder_config->video_format.name = payload_name_;
const VideoCodecType codec_type = PayloadStringToCodecType(payload_name_);
encoder_config->codec_type = codec_type;
encoder_config->max_bitrate_bps =
std::max(start_bps_, encoder_config->max_bitrate_bps);
if (payload_name_ == "VP9") {
// Simulcast layers indicates which spatial layers are active.
encoder_config->simulcast_layers.resize(test_params_.size());
encoder_config->simulcast_layers[0].max_bitrate_bps =
encoder_config->max_bitrate_bps;
}
double scale_factor = 1.0;
for (int i = test_params_.size() - 1; i >= 0; --i) {
VideoStream& stream = encoder_config->simulcast_layers[i];
stream.active = test_params_[i].active;
stream.scalability_mode = test_params_[i].scalability_mode;
stream.scale_resolution_down_by = scale_factor;
scale_factor *= (payload_name_ == "VP9") ? 1.0 : 2.0;
}
encoder_config->frame_drop_enabled = true;
SetEncoderSpecific(encoder_config, codec_type, automatic_resize_,
test_params_.size());
}
Action OnSendRtp(rtc::ArrayView<const uint8_t> packet) override {
// The tests are expected to send at the configured start bitrate. Do not
// send any packets to avoid receiving REMB and possibly go down in target
// bitrate. A low bitrate estimate could result in downgrading due to other
// reasons than low/high QP-value (e.g. high frame drop percent) or not
// upgrading due to bitrate constraint.
return DROP_PACKET;
}
void PerformTest() override { EXPECT_EQ(expect_scaling_, Wait()); }
test::FunctionVideoEncoderFactory encoder_factory_;
const std::string payload_name_;
const std::vector<TestParams> test_params_;
const int start_bps_;
const bool automatic_resize_;
const bool expect_scaling_;
};
class DownscalingObserver
: public ScalingObserver,
public test::FrameGeneratorCapturer::SinkWantsObserver {
public:
DownscalingObserver(const std::string& payload_name,
const std::vector<TestParams>& test_params,
int start_bps,
bool automatic_resize,
bool expect_downscale)
: ScalingObserver(payload_name,
test_params,
start_bps,
automatic_resize,
expect_downscale) {}
private:
void OnFrameGeneratorCapturerCreated(
test::FrameGeneratorCapturer* frame_generator_capturer) override {
frame_generator_capturer->SetSinkWantsObserver(this);
frame_generator_capturer->ChangeResolution(kInitialWidth, kInitialHeight);
}
void OnSinkWantsChanged(rtc::VideoSinkInterface<VideoFrame>* sink,
const rtc::VideoSinkWants& wants) override {
if (wants.max_pixel_count < kInitialWidth * kInitialHeight)
observation_complete_.Set();
}
};
class UpscalingObserver
: public ScalingObserver,
public test::FrameGeneratorCapturer::SinkWantsObserver {
public:
UpscalingObserver(const std::string& payload_name,
const std::vector<TestParams>& test_params,
int start_bps,
bool automatic_resize,
bool expect_upscale)
: ScalingObserver(payload_name,
test_params,
start_bps,
automatic_resize,
expect_upscale) {}
void SetDegradationPreference(DegradationPreference preference) {
degradation_preference_ = preference;
}
private:
void OnFrameGeneratorCapturerCreated(
test::FrameGeneratorCapturer* frame_generator_capturer) override {
frame_generator_capturer->SetSinkWantsObserver(this);
frame_generator_capturer->ChangeResolution(kInitialWidth, kInitialHeight);
}
void OnSinkWantsChanged(rtc::VideoSinkInterface<VideoFrame>* sink,
const rtc::VideoSinkWants& wants) override {
if (wants.max_pixel_count > last_wants_.max_pixel_count) {
if (wants.max_pixel_count == std::numeric_limits<int>::max())
observation_complete_.Set();
}
last_wants_ = wants;
}
rtc::VideoSinkWants last_wants_;
};
TEST_F(QualityScalingTest, AdaptsDownForHighQp_Vp8) {
// qp_low:1, qp_high:1 -> kHighQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,1,0,0,0,0" + kEnd);
DownscalingObserver test("VP8", {{.active = true}}, kHighStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/true);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, NoAdaptDownForHighQpIfScalingOff_Vp8) {
// qp_low:1, qp_high:1 -> kHighQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,1,0,0,0,0" + kEnd);
DownscalingObserver test("VP8", {{.active = true}}, kHighStartBps,
/*automatic_resize=*/false,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, NoAdaptDownForNormalQp_Vp8) {
// qp_low:1, qp_high:127 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,127,0,0,0,0" + kEnd);
DownscalingObserver test("VP8", {{.active = true}}, kHighStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, AdaptsDownForLowStartBitrate_Vp8) {
// qp_low:1, qp_high:127 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,127,0,0,0,0" + kEnd);
DownscalingObserver test("VP8", {{.active = true}}, kLowStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/true);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, AdaptsDownForLowStartBitrateAndThenUp) {
// qp_low:127, qp_high:127 -> kLowQp
test::ScopedKeyValueConfig field_trials(
field_trials_,
kPrefix + "127,127,0,0,0,0" + kEnd +
"WebRTC-Video-BalancedDegradationSettings/"
"pixels:230400|921600,fps:20|30,kbps:300|500/"); // should not affect
UpscalingObserver test("VP8", {{.active = true}}, kDefaultVgaMinStartBps - 1,
/*automatic_resize=*/true, /*expect_upscale=*/true);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, AdaptsDownAndThenUpWithBalanced) {
// qp_low:127, qp_high:127 -> kLowQp
test::ScopedKeyValueConfig field_trials(
field_trials_, kPrefix + "127,127,0,0,0,0" + kEnd +
"WebRTC-Video-BalancedDegradationSettings/"
"pixels:230400|921600,fps:20|30,kbps:300|499/");
UpscalingObserver test("VP8", {{.active = true}}, kDefaultVgaMinStartBps - 1,
/*automatic_resize=*/true, /*expect_upscale=*/true);
test.SetDegradationPreference(DegradationPreference::BALANCED);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, AdaptsDownButNotUpWithBalancedIfBitrateNotEnough) {
// qp_low:127, qp_high:127 -> kLowQp
test::ScopedKeyValueConfig field_trials(
field_trials_, kPrefix + "127,127,0,0,0,0" + kEnd +
"WebRTC-Video-BalancedDegradationSettings/"
"pixels:230400|921600,fps:20|30,kbps:300|500/");
UpscalingObserver test("VP8", {{.active = true}}, kDefaultVgaMinStartBps - 1,
/*automatic_resize=*/true, /*expect_upscale=*/false);
test.SetDegradationPreference(DegradationPreference::BALANCED);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, NoAdaptDownForLowStartBitrate_Simulcast) {
// qp_low:1, qp_high:127 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,127,0,0,0,0" + kEnd);
DownscalingObserver test("VP8", {{.active = true}, {.active = true}},
kLowStartBps,
/*automatic_resize=*/false,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, AdaptsDownForHighQp_HighestStreamActive_Vp8) {
// qp_low:1, qp_high:1 -> kHighQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,1,0,0,0,0" + kEnd);
DownscalingObserver test(
"VP8", {{.active = false}, {.active = false}, {.active = true}},
kHighStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/true);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest,
AdaptsDownForLowStartBitrate_HighestStreamActive_Vp8) {
// qp_low:1, qp_high:127 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,127,0,0,0,0" + kEnd);
DownscalingObserver test(
"VP8", {{.active = false}, {.active = false}, {.active = true}},
kSinglecastLimits720pVp8->min_start_bitrate_bps - 1,
/*automatic_resize=*/true,
/*expect_downscale=*/true);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, AdaptsDownButNotUpWithMinStartBitrateLimit) {
// qp_low:127, qp_high:127 -> kLowQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "127,127,0,0,0,0" + kEnd);
UpscalingObserver test("VP8", {{.active = false}, {.active = true}},
kSinglecastLimits720pVp8->min_start_bitrate_bps - 1,
/*automatic_resize=*/true, /*expect_upscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, NoAdaptDownForLowStartBitrateIfBitrateEnough_Vp8) {
// qp_low:1, qp_high:127 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,127,0,0,0,0" + kEnd);
DownscalingObserver test(
"VP8", {{.active = false}, {.active = false}, {.active = true}},
kSinglecastLimits720pVp8->min_start_bitrate_bps,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest,
NoAdaptDownForLowStartBitrateIfDefaultLimitsDisabled_Vp8) {
// qp_low:1, qp_high:127 -> kNormalQp
test::ScopedKeyValueConfig field_trials(
field_trials_, kPrefix + "1,127,0,0,0,0" + kEnd +
"WebRTC-DefaultBitrateLimitsKillSwitch/Enabled/");
DownscalingObserver test(
"VP8", {{.active = false}, {.active = false}, {.active = true}},
kSinglecastLimits720pVp8->min_start_bitrate_bps - 1,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest,
NoAdaptDownForLowStartBitrate_OneStreamSinglecastLimitsNotUsed_Vp8) {
// qp_low:1, qp_high:127 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,127,0,0,0,0" + kEnd);
DownscalingObserver test("VP8", {{.active = true}},
kSinglecastLimits720pVp8->min_start_bitrate_bps - 1,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, NoAdaptDownForHighQp_LowestStreamActive_Vp8) {
// qp_low:1, qp_high:1 -> kHighQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,1,0,0,0,0" + kEnd);
DownscalingObserver test(
"VP8", {{.active = true}, {.active = false}, {.active = false}},
kHighStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest,
NoAdaptDownForLowStartBitrate_LowestStreamActive_Vp8) {
// qp_low:1, qp_high:127 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,127,0,0,0,0" + kEnd);
DownscalingObserver test(
"VP8", {{.active = true}, {.active = false}, {.active = false}},
kLowStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, NoAdaptDownForLowStartBitrateIfScalingOff_Vp8) {
// qp_low:1, qp_high:127 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "1,127,0,0,0,0" + kEnd);
DownscalingObserver test("VP8", {{.active = true}}, kLowStartBps,
/*automatic_resize=*/false,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, AdaptsDownForHighQp_Vp9) {
// qp_low:1, qp_high:1 -> kHighQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,1,1,0,0" + kEnd);
DownscalingObserver test("VP9", {{.active = true}}, kHighStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/true);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, NoAdaptDownForHighQpIfScalingOff_Vp9) {
// qp_low:1, qp_high:1 -> kHighQp
test::ScopedKeyValueConfig field_trials(
field_trials_,
kPrefix + "0,0,1,1,0,0" + kEnd + "WebRTC-VP9QualityScaler/Disabled/");
DownscalingObserver test("VP9", {{.active = true}}, kHighStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, AdaptsDownForLowStartBitrate_Vp9) {
// qp_low:1, qp_high:255 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,1,255,0,0" + kEnd);
DownscalingObserver test("VP9", {{.active = true}}, kLowStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/true);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, NoAdaptDownForHighStartBitrate_Vp9) {
DownscalingObserver test(
"VP9", {{.active = false}, {.active = false}, {.active = true}},
kHighStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, NoAdaptDownForHighQp_LowestStreamActive_Vp9) {
// qp_low:1, qp_high:1 -> kHighQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,1,1,0,0" + kEnd);
DownscalingObserver test(
"VP9", {{.active = true}, {.active = false}, {.active = false}},
kHighStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest,
NoAdaptDownForLowStartBitrate_LowestStreamActive_Vp9) {
// qp_low:1, qp_high:255 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,1,255,0,0" + kEnd);
DownscalingObserver test(
"VP9", {{.active = true}, {.active = false}, {.active = false}},
kLowStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, AdaptsDownForHighQp_MiddleStreamActive_Vp9) {
// qp_low:1, qp_high:1 -> kHighQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,1,1,0,0" + kEnd);
DownscalingObserver test(
"VP9", {{.active = false}, {.active = true}, {.active = false}},
kHighStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/true);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest,
AdaptsDownForLowStartBitrate_MiddleStreamActive_Vp9) {
// qp_low:1, qp_high:255 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,1,255,0,0" + kEnd);
DownscalingObserver test(
"VP9", {{.active = false}, {.active = true}, {.active = false}},
kSinglecastLimits360pVp9->min_start_bitrate_bps - 1,
/*automatic_resize=*/true,
/*expect_downscale=*/true);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, NoAdaptDownForLowStartBitrateIfBitrateEnough_Vp9) {
// qp_low:1, qp_high:255 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,1,255,0,0" + kEnd);
DownscalingObserver test(
"VP9", {{.active = false}, {.active = true}, {.active = false}},
kSinglecastLimits360pVp9->min_start_bitrate_bps,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest,
AdaptsDownButNotUpWithMinStartBitrateLimitWithScalabilityMode_VP9) {
// qp_low:255, qp_high:255 -> kLowQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,255,255,0,0" + kEnd);
UpscalingObserver test(
"VP9",
{{.active = true, .scalability_mode = ScalabilityMode::kL1T3},
{.active = false}},
kSinglecastLimits720pVp9->min_start_bitrate_bps - 1,
/*automatic_resize=*/true, /*expect_upscale=*/false);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest,
NoAdaptDownForLowStartBitrateIfBitrateEnoughWithScalabilityMode_Vp9) {
// qp_low:1, qp_high:255 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,1,255,0,0" + kEnd);
DownscalingObserver test(
"VP9",
{{.active = true, .scalability_mode = ScalabilityMode::kL1T3},
{.active = false},
{.active = false}},
kSinglecastLimits720pVp9->min_start_bitrate_bps,
/*automatic_resize=*/true,
/*expect_downscale=*/false);
RunBaseTest(&test);
}
#if defined(WEBRTC_USE_H264)
TEST_F(QualityScalingTest, AdaptsDownForHighQp_H264) {
// qp_low:1, qp_high:1 -> kHighQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,0,0,1,1" + kEnd);
DownscalingObserver test("H264", {{.active = true}}, kHighStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/true);
RunBaseTest(&test);
}
TEST_F(QualityScalingTest, AdaptsDownForLowStartBitrate_H264) {
// qp_low:1, qp_high:51 -> kNormalQp
test::ScopedKeyValueConfig field_trials(field_trials_,
kPrefix + "0,0,0,0,1,51" + kEnd);
DownscalingObserver test("H264", {{.active = true}}, kLowStartBps,
/*automatic_resize=*/true,
/*expect_downscale=*/true);
RunBaseTest(&test);
}
#endif // defined(WEBRTC_USE_H264)
} // namespace webrtc