summaryrefslogtreecommitdiffstats
path: root/third_party/libwebrtc/modules/video_coding/deprecated/receiver.cc
blob: b76084779d76310cf69c05af1e1668e2e07bf738 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/*
 *  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/deprecated/receiver.h"

#include <cstdint>
#include <cstdlib>
#include <utility>
#include <vector>

#include "absl/memory/memory.h"
#include "api/video/encoded_image.h"
#include "modules/video_coding/deprecated/jitter_buffer_common.h"
#include "modules/video_coding/encoded_frame.h"
#include "modules/video_coding/internal_defines.h"
#include "rtc_base/logging.h"
#include "rtc_base/numerics/safe_conversions.h"
#include "rtc_base/trace_event.h"
#include "system_wrappers/include/clock.h"

namespace webrtc {

enum { kMaxReceiverDelayMs = 10000 };

VCMReceiver::VCMReceiver(VCMTiming* timing,
                         Clock* clock,
                         const FieldTrialsView& field_trials)
    : VCMReceiver::VCMReceiver(timing,
                               clock,
                               absl::WrapUnique(EventWrapper::Create()),
                               absl::WrapUnique(EventWrapper::Create()),
                               field_trials) {}

VCMReceiver::VCMReceiver(VCMTiming* timing,
                         Clock* clock,
                         std::unique_ptr<EventWrapper> receiver_event,
                         std::unique_ptr<EventWrapper> jitter_buffer_event,
                         const FieldTrialsView& field_trials)
    : clock_(clock),
      jitter_buffer_(clock_, std::move(jitter_buffer_event), field_trials),
      timing_(timing),
      render_wait_event_(std::move(receiver_event)),
      max_video_delay_ms_(kMaxVideoDelayMs) {
  jitter_buffer_.Start();
}

VCMReceiver::~VCMReceiver() {
  render_wait_event_->Set();
}

int32_t VCMReceiver::InsertPacket(const VCMPacket& packet) {
  // Insert the packet into the jitter buffer. The packet can either be empty or
  // contain media at this point.
  bool retransmitted = false;
  const VCMFrameBufferEnum ret =
      jitter_buffer_.InsertPacket(packet, &retransmitted);
  if (ret == kOldPacket) {
    return VCM_OK;
  } else if (ret == kFlushIndicator) {
    return VCM_FLUSH_INDICATOR;
  } else if (ret < 0) {
    return VCM_JITTER_BUFFER_ERROR;
  }
  if (ret == kCompleteSession && !retransmitted) {
    // We don't want to include timestamps which have suffered from
    // retransmission here, since we compensate with extra retransmission
    // delay within the jitter estimate.
    timing_->IncomingTimestamp(packet.timestamp, clock_->CurrentTime());
  }
  return VCM_OK;
}

VCMEncodedFrame* VCMReceiver::FrameForDecoding(uint16_t max_wait_time_ms,
                                               bool prefer_late_decoding) {
  const int64_t start_time_ms = clock_->TimeInMilliseconds();
  int64_t render_time_ms = 0;
  // Exhaust wait time to get a complete frame for decoding.
  VCMEncodedFrame* found_frame =
      jitter_buffer_.NextCompleteFrame(max_wait_time_ms);

  if (found_frame == nullptr) {
    return nullptr;
  }
  uint32_t frame_timestamp = found_frame->RtpTimestamp();

  if (absl::optional<VideoPlayoutDelay> playout_delay =
          found_frame->EncodedImage().PlayoutDelay()) {
    timing_->set_min_playout_delay(playout_delay->min());
    timing_->set_max_playout_delay(playout_delay->max());
  }

  // We have a frame - Set timing and render timestamp.
  timing_->SetJitterDelay(
      TimeDelta::Millis(jitter_buffer_.EstimatedJitterMs()));
  const Timestamp now = clock_->CurrentTime();
  const int64_t now_ms = now.ms();
  timing_->UpdateCurrentDelay(frame_timestamp);
  render_time_ms = timing_->RenderTime(frame_timestamp, now).ms();
  // Check render timing.
  bool timing_error = false;
  // Assume that render timing errors are due to changes in the video stream.
  if (render_time_ms < 0) {
    timing_error = true;
  } else if (std::abs(render_time_ms - now_ms) > max_video_delay_ms_) {
    int frame_delay = static_cast<int>(std::abs(render_time_ms - now_ms));
    RTC_LOG(LS_WARNING)
        << "A frame about to be decoded is out of the configured "
           "delay bounds ("
        << frame_delay << " > " << max_video_delay_ms_
        << "). Resetting the video jitter buffer.";
    timing_error = true;
  } else if (static_cast<int>(timing_->TargetVideoDelay().ms()) >
             max_video_delay_ms_) {
    RTC_LOG(LS_WARNING) << "The video target delay has grown larger than "
                        << max_video_delay_ms_
                        << " ms. Resetting jitter buffer.";
    timing_error = true;
  }

  if (timing_error) {
    // Timing error => reset timing and flush the jitter buffer.
    jitter_buffer_.Flush();
    timing_->Reset();
    return NULL;
  }

  if (prefer_late_decoding) {
    // Decode frame as close as possible to the render timestamp.
    const int32_t available_wait_time =
        max_wait_time_ms -
        static_cast<int32_t>(clock_->TimeInMilliseconds() - start_time_ms);
    uint16_t new_max_wait_time =
        static_cast<uint16_t>(VCM_MAX(available_wait_time, 0));
    uint32_t wait_time_ms = rtc::saturated_cast<uint32_t>(
        timing_
            ->MaxWaitingTime(Timestamp::Millis(render_time_ms),
                             clock_->CurrentTime(),
                             /*too_many_frames_queued=*/false)
            .ms());
    if (new_max_wait_time < wait_time_ms) {
      // We're not allowed to wait until the frame is supposed to be rendered,
      // waiting as long as we're allowed to avoid busy looping, and then return
      // NULL. Next call to this function might return the frame.
      render_wait_event_->Wait(new_max_wait_time);
      return NULL;
    }
    // Wait until it's time to render.
    render_wait_event_->Wait(wait_time_ms);
  }

  // Extract the frame from the jitter buffer and set the render time.
  VCMEncodedFrame* frame = jitter_buffer_.ExtractAndSetDecode(frame_timestamp);
  if (frame == NULL) {
    return NULL;
  }
  frame->SetRenderTime(render_time_ms);
  TRACE_EVENT_ASYNC_STEP1("webrtc", "Video", frame->RtpTimestamp(),
                          "SetRenderTS", "render_time", frame->RenderTimeMs());
  return frame;
}

void VCMReceiver::ReleaseFrame(VCMEncodedFrame* frame) {
  jitter_buffer_.ReleaseFrame(frame);
}

void VCMReceiver::SetNackSettings(size_t max_nack_list_size,
                                  int max_packet_age_to_nack,
                                  int max_incomplete_time_ms) {
  jitter_buffer_.SetNackSettings(max_nack_list_size, max_packet_age_to_nack,
                                 max_incomplete_time_ms);
}

std::vector<uint16_t> VCMReceiver::NackList(bool* request_key_frame) {
  return jitter_buffer_.GetNackList(request_key_frame);
}

}  // namespace webrtc