VideoCaptureInput enforce VideoFrame::render_time to be generated by webrtc clock.

webrtc/video/video_capture_input.cc

 /*
  *  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 "webrtc/video/video_capture_input.h"
 
 #include "webrtc/base/checks.h"
 #include "webrtc/base/logging.h"
 #include "webrtc/base/trace_event.h"
 #include "webrtc/modules/include/module_common_types.h"
 #include "webrtc/modules/video_capture/video_capture_factory.h"
 #include "webrtc/modules/video_processing/include/video_processing.h"
 #include "webrtc/modules/video_render/video_render_defines.h"
-#include "webrtc/system_wrappers/include/clock.h"
-#include "webrtc/system_wrappers/include/tick_util.h"
 #include "webrtc/video/overuse_frame_detector.h"
 #include "webrtc/video/send_statistics_proxy.h"
 #include "webrtc/video/vie_encoder.h"
 
 namespace webrtc {
 
 namespace internal {
 VideoCaptureInput::VideoCaptureInput(VideoCaptureCallback* frame_callback,
                                      VideoRenderer* local_renderer,
                                      SendStatisticsProxy* stats_proxy,
                                      OveruseFrameDetector* overuse_detector)
     : frame_callback_(frame_callback),
       local_renderer_(local_renderer),
       stats_proxy_(stats_proxy),
       encoder_thread_(EncoderThreadFunction, this, "EncoderThread"),
       capture_event_(false, false),
       stop_(0),
+      // TODO(danilchap): Pass clock from outside to ensure it is same clock
+      // rtcp module use to calculate offset since last frame captured
+      // to estimate rtp timestamp for SenderReport.
+      clock_(Clock::GetRealTimeClock()),
       last_captured_timestamp_(0),
-      delta_ntp_internal_ms_(
-          Clock::GetRealTimeClock()->CurrentNtpInMilliseconds() -
-          TickTime::MillisecondTimestamp()),
+      delta_ntp_internal_ms_(clock_->CurrentNtpInMilliseconds() -
+                             clock_->TimeInMilliseconds()),
       overuse_detector_(overuse_detector) {
   encoder_thread_.Start();
   encoder_thread_.SetPriority(rtc::kHighPriority);
 }
 
 VideoCaptureInput::~VideoCaptureInput() {
   // Stop the thread.
   rtc::AtomicOps::ReleaseStore(&stop_, 1);
   capture_event_.Set();
   encoder_thread_.Stop();
 }
 
 void VideoCaptureInput::IncomingCapturedFrame(const VideoFrame& video_frame) {
   // TODO(pbos): Remove local rendering, it should be handled by the client code
   // if required.
   if (local_renderer_)
     local_renderer_->RenderFrame(video_frame, 0);
 
   stats_proxy_->OnIncomingFrame(video_frame.width(), video_frame.height());
 
   VideoFrame incoming_frame = video_frame;
 
-  if (incoming_frame.ntp_time_ms() != 0) {
-    // If a NTP time stamp is set, this is the time stamp we will use.
-    incoming_frame.set_render_time_ms(incoming_frame.ntp_time_ms() -
-                                      delta_ntp_internal_ms_);
-  } else {  // NTP time stamp not set.
-    int64_t render_time = incoming_frame.render_time_ms() != 0
-                              ? incoming_frame.render_time_ms()
-                              : TickTime::MillisecondTimestamp();
+  // Local time in webrtc time base.
+  int64_t current_time = clock_->TimeInMilliseconds();
+  incoming_frame.set_render_time_ms(current_time);
 
-    incoming_frame.set_render_time_ms(render_time);
-    incoming_frame.set_ntp_time_ms(render_time + delta_ntp_internal_ms_);
+  // Capture time may come from clock with an offset and drift from clock_.
+  int64_t capture_ntp_time_ms;
+  if (video_frame.ntp_time_ms() != 0) {
+    capture_ntp_time_ms = video_frame.ntp_time_ms();
+  } else if (video_frame.render_time_ms() != 0) {
+    capture_ntp_time_ms = video_frame.render_time_ms() + delta_ntp_internal_ms_;
+  } else {
+    capture_ntp_time_ms = current_time + delta_ntp_internal_ms_;
   }
+  incoming_frame.set_ntp_time_ms(capture_ntp_time_ms);
 
   // Convert NTP time, in ms, to RTP timestamp.
   const int kMsToRtpTimestamp = 90;
   incoming_frame.set_timestamp(
       kMsToRtpTimestamp * static_cast<uint32_t>(incoming_frame.ntp_time_ms()));
 
   rtc::CritScope lock(&crit_);
   if (incoming_frame.ntp_time_ms() <= last_captured_timestamp_) {
     // We don't allow the same capture time for two frames, drop this one.
     LOG(LS_WARNING) << "Same/old NTP timestamp ("
@@ skipping 34 matching lines @@
     }
     if (!deliver_frame.IsZeroSize()) {
       frame_callback_->DeliverFrame(deliver_frame);
     }
   }
   return true;
 }
 
 }  // namespace internal
 }  // namespace webrtc