1 /*
2  *  Copyright (c) 2020 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #include "api/stats/rtc_stats_collector_callback.h"
12 #include "api/stats/rtcstats_objects.h"
13 #include "pc/test/mock_peer_connection_observers.h"
14 #include "test/field_trial.h"
15 #include "test/gtest.h"
16 #include "test/peer_scenario/peer_scenario.h"
17 #include "test/peer_scenario/peer_scenario_client.h"
18 
19 namespace webrtc {
20 namespace test {
21 
22 // TODO(terelius): Use fake encoder and enable on Android once
23 // https://bugs.chromium.org/p/webrtc/issues/detail?id=11408 is fixed.
24 #if defined(WEBRTC_ANDROID)
25 #define MAYBE_NoBweChangeFromVideoUnmute DISABLED_NoBweChangeFromVideoUnmute
26 #else
27 #define MAYBE_NoBweChangeFromVideoUnmute NoBweChangeFromVideoUnmute
28 #endif
TEST(GoogCcPeerScenarioTest,MAYBE_NoBweChangeFromVideoUnmute)29 TEST(GoogCcPeerScenarioTest, MAYBE_NoBweChangeFromVideoUnmute) {
30   // If transport wide sequence numbers are used for audio, and the call
31   // switches from audio only to video only, there will be a sharp change in
32   // packets sizes. This will create a change in propagation time which might be
33   // detected as an overuse. Using separate overuse detectors for audio and
34   // video avoids the issue.
35   std::string audio_twcc_trials(
36       "WebRTC-Audio-SendSideBwe/Enabled/"         //
37       "WebRTC-SendSideBwe-WithOverhead/Enabled/"  //
38       "WebRTC-Audio-AlrProbing/Disabled/");
39   std::string separate_audio_video(
40       "WebRTC-Bwe-SeparateAudioPackets/"
41       "enabled:true,packet_threshold:15,time_threshold:1000ms/");
42   ScopedFieldTrials field_trial(audio_twcc_trials + separate_audio_video);
43   PeerScenario s(*test_info_);
44   auto* caller = s.CreateClient(PeerScenarioClient::Config());
45   auto* callee = s.CreateClient(PeerScenarioClient::Config());
46 
47   BuiltInNetworkBehaviorConfig net_conf;
48   net_conf.link_capacity_kbps = 350;
49   net_conf.queue_delay_ms = 50;
50   auto send_node = s.net()->CreateEmulatedNode(net_conf);
51   auto ret_node = s.net()->CreateEmulatedNode(net_conf);
52 
53   PeerScenarioClient::VideoSendTrackConfig video_conf;
54   video_conf.generator.squares_video->framerate = 15;
55   auto video = caller->CreateVideo("VIDEO", video_conf);
56   auto audio = caller->CreateAudio("AUDIO", cricket::AudioOptions());
57 
58   // Start ICE and exchange SDP.
59   s.SimpleConnection(caller, callee, {send_node}, {ret_node});
60 
61   // Limit the encoder bitrate to ensure that there are no actual BWE overuses.
62   ASSERT_EQ(caller->pc()->GetSenders().size(), 2u);  // 2 senders.
63   int num_video_streams = 0;
64   for (auto& rtp_sender : caller->pc()->GetSenders()) {
65     auto parameters = rtp_sender->GetParameters();
66     ASSERT_EQ(parameters.encodings.size(), 1u);  // 1 stream per sender.
67     for (auto& encoding_parameters : parameters.encodings) {
68       if (encoding_parameters.ssrc == video.sender->ssrc()) {
69         num_video_streams++;
70         encoding_parameters.max_bitrate_bps = 220000;
71         encoding_parameters.max_framerate = 15;
72       }
73     }
74     rtp_sender->SetParameters(parameters);
75   }
76   ASSERT_EQ(num_video_streams, 1);  // Exactly 1 video stream.
77 
78   auto get_bwe = [&] {
79     rtc::scoped_refptr<webrtc::MockRTCStatsCollectorCallback> callback(
80         new rtc::RefCountedObject<webrtc::MockRTCStatsCollectorCallback>());
81     caller->pc()->GetStats(callback);
82     s.net()->time_controller()->Wait([&] { return callback->called(); });
83     auto stats =
84         callback->report()->GetStatsOfType<RTCIceCandidatePairStats>()[0];
85     return DataRate::BitsPerSec(*stats->available_outgoing_bitrate);
86   };
87 
88   s.ProcessMessages(TimeDelta::Seconds(15));
89   const DataRate initial_bwe = get_bwe();
90   EXPECT_GE(initial_bwe, DataRate::KilobitsPerSec(300));
91 
92   // 10 seconds audio only. Bandwidth should not drop.
93   video.capturer->Stop();
94   s.ProcessMessages(TimeDelta::Seconds(10));
95   EXPECT_GE(get_bwe(), initial_bwe);
96 
97   // Resume video but stop audio. Bandwidth should not drop.
98   video.capturer->Start();
99   RTCError status = caller->pc()->RemoveTrackNew(audio.sender);
100   ASSERT_TRUE(status.ok());
101   audio.track->set_enabled(false);
102   for (int i = 0; i < 10; i++) {
103     s.ProcessMessages(TimeDelta::Seconds(1));
104     EXPECT_GE(get_bwe(), initial_bwe);
105   }
106 }
107 
108 }  // namespace test
109 }  // namespace webrtc
110