Incorrect timestamps used by video analyzer with real camera

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.
  */
 
@@ skipping 49 matching lines @@
 
 VideoCaptureInput::~VideoCaptureInput() {
   module_process_thread_->DeRegisterModule(overuse_detector_.get());
 
   // 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 VideoCaptureInput::UpdateTimestamps(const VideoFrame& video_frame) {
   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();
 
     incoming_frame.set_render_time_ms(render_time);
     incoming_frame.set_ntp_time_ms(render_time + delta_ntp_internal_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()));
 
+  return incoming_frame;
+}
+
+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);

[pbos-webrtc, 2015/12/18 16:23:16]

Use this callback instead of wrapping input, but move this until after we set
the timestamp.

[sprang_webrtc, 2015/12/18 16:52:57]

Done.

+
+  stats_proxy_->OnIncomingFrame(video_frame.width(), video_frame.height());
+
+  VideoFrame incoming_frame = UpdateTimestamps(video_frame);
+
   CriticalSectionScoped cs(capture_cs_.get());
   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 ("
                     << incoming_frame.ntp_time_ms()
                     << " <= " << last_captured_timestamp_
                     << ") for incoming frame. Dropping.";
     return;
   }
 
@@ skipping 49 matching lines @@
   }
   // We're done!
   if (capture_time != -1) {
     overuse_detector_->FrameSent(capture_time);
   }
   return true;
 }
 
 }  // namespace internal
 }  // namespace webrtc