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      1 /*
      2  *  Copyright (c) 2012 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 "webrtc/video/video_capture_input.h"
     12 
     13 #include "webrtc/base/checks.h"
     14 #include "webrtc/base/logging.h"
     15 #include "webrtc/base/trace_event.h"
     16 #include "webrtc/modules/include/module_common_types.h"
     17 #include "webrtc/modules/utility/include/process_thread.h"
     18 #include "webrtc/modules/video_capture/video_capture_factory.h"
     19 #include "webrtc/modules/video_processing/include/video_processing.h"
     20 #include "webrtc/modules/video_render/video_render_defines.h"
     21 #include "webrtc/system_wrappers/include/clock.h"
     22 #include "webrtc/system_wrappers/include/critical_section_wrapper.h"
     23 #include "webrtc/system_wrappers/include/tick_util.h"
     24 #include "webrtc/video/overuse_frame_detector.h"
     25 #include "webrtc/video/send_statistics_proxy.h"
     26 #include "webrtc/video/vie_encoder.h"
     27 
     28 namespace webrtc {
     29 
     30 namespace internal {
     31 VideoCaptureInput::VideoCaptureInput(
     32     ProcessThread* module_process_thread,
     33     VideoCaptureCallback* frame_callback,
     34     VideoRenderer* local_renderer,
     35     SendStatisticsProxy* stats_proxy,
     36     CpuOveruseObserver* overuse_observer,
     37     EncodingTimeObserver* encoding_time_observer)
     38     : capture_cs_(CriticalSectionWrapper::CreateCriticalSection()),
     39       module_process_thread_(module_process_thread),
     40       frame_callback_(frame_callback),
     41       local_renderer_(local_renderer),
     42       stats_proxy_(stats_proxy),
     43       incoming_frame_cs_(CriticalSectionWrapper::CreateCriticalSection()),
     44       encoder_thread_(EncoderThreadFunction, this, "EncoderThread"),
     45       capture_event_(false, false),
     46       stop_(0),
     47       last_captured_timestamp_(0),
     48       delta_ntp_internal_ms_(
     49           Clock::GetRealTimeClock()->CurrentNtpInMilliseconds() -
     50           TickTime::MillisecondTimestamp()),
     51       overuse_detector_(new OveruseFrameDetector(Clock::GetRealTimeClock(),
     52                                                  CpuOveruseOptions(),
     53                                                  overuse_observer,
     54                                                  stats_proxy)),
     55       encoding_time_observer_(encoding_time_observer) {
     56   encoder_thread_.Start();
     57   encoder_thread_.SetPriority(rtc::kHighPriority);
     58   module_process_thread_->RegisterModule(overuse_detector_.get());
     59 }
     60 
     61 VideoCaptureInput::~VideoCaptureInput() {
     62   module_process_thread_->DeRegisterModule(overuse_detector_.get());
     63 
     64   // Stop the thread.
     65   rtc::AtomicOps::ReleaseStore(&stop_, 1);
     66   capture_event_.Set();
     67   encoder_thread_.Stop();
     68 }
     69 
     70 void VideoCaptureInput::IncomingCapturedFrame(const VideoFrame& video_frame) {
     71   // TODO(pbos): Remove local rendering, it should be handled by the client code
     72   // if required.
     73   if (local_renderer_)
     74     local_renderer_->RenderFrame(video_frame, 0);
     75 
     76   stats_proxy_->OnIncomingFrame(video_frame.width(), video_frame.height());
     77 
     78   VideoFrame incoming_frame = video_frame;
     79 
     80   if (incoming_frame.ntp_time_ms() != 0) {
     81     // If a NTP time stamp is set, this is the time stamp we will use.
     82     incoming_frame.set_render_time_ms(incoming_frame.ntp_time_ms() -
     83                                       delta_ntp_internal_ms_);
     84   } else {  // NTP time stamp not set.
     85     int64_t render_time = incoming_frame.render_time_ms() != 0
     86                               ? incoming_frame.render_time_ms()
     87                               : TickTime::MillisecondTimestamp();
     88 
     89     incoming_frame.set_render_time_ms(render_time);
     90     incoming_frame.set_ntp_time_ms(render_time + delta_ntp_internal_ms_);
     91   }
     92 
     93   // Convert NTP time, in ms, to RTP timestamp.
     94   const int kMsToRtpTimestamp = 90;
     95   incoming_frame.set_timestamp(
     96       kMsToRtpTimestamp * static_cast<uint32_t>(incoming_frame.ntp_time_ms()));
     97 
     98   CriticalSectionScoped cs(capture_cs_.get());
     99   if (incoming_frame.ntp_time_ms() <= last_captured_timestamp_) {
    100     // We don't allow the same capture time for two frames, drop this one.
    101     LOG(LS_WARNING) << "Same/old NTP timestamp ("
    102                     << incoming_frame.ntp_time_ms()
    103                     << " <= " << last_captured_timestamp_
    104                     << ") for incoming frame. Dropping.";
    105     return;
    106   }
    107 
    108   captured_frame_.ShallowCopy(incoming_frame);
    109   last_captured_timestamp_ = incoming_frame.ntp_time_ms();
    110 
    111   overuse_detector_->FrameCaptured(captured_frame_.width(),
    112                                    captured_frame_.height(),
    113                                    captured_frame_.render_time_ms());
    114 
    115   TRACE_EVENT_ASYNC_BEGIN1("webrtc", "Video", video_frame.render_time_ms(),
    116                            "render_time", video_frame.render_time_ms());
    117 
    118   capture_event_.Set();
    119 }
    120 
    121 bool VideoCaptureInput::EncoderThreadFunction(void* obj) {
    122   return static_cast<VideoCaptureInput*>(obj)->EncoderProcess();
    123 }
    124 
    125 bool VideoCaptureInput::EncoderProcess() {
    126   static const int kThreadWaitTimeMs = 100;
    127   int64_t capture_time = -1;
    128   if (capture_event_.Wait(kThreadWaitTimeMs)) {
    129     if (rtc::AtomicOps::AcquireLoad(&stop_))
    130       return false;
    131 
    132     int64_t encode_start_time = -1;
    133     VideoFrame deliver_frame;
    134     {
    135       CriticalSectionScoped cs(capture_cs_.get());
    136       if (!captured_frame_.IsZeroSize()) {
    137         deliver_frame = captured_frame_;
    138         captured_frame_.Reset();
    139       }
    140     }
    141     if (!deliver_frame.IsZeroSize()) {
    142       capture_time = deliver_frame.render_time_ms();
    143       encode_start_time = Clock::GetRealTimeClock()->TimeInMilliseconds();
    144       frame_callback_->DeliverFrame(deliver_frame);
    145     }
    146     // Update the overuse detector with the duration.
    147     if (encode_start_time != -1) {
    148       int encode_time_ms = static_cast<int>(
    149           Clock::GetRealTimeClock()->TimeInMilliseconds() - encode_start_time);
    150       stats_proxy_->OnEncodedFrame(encode_time_ms);
    151       if (encoding_time_observer_) {
    152         encoding_time_observer_->OnReportEncodedTime(
    153             deliver_frame.ntp_time_ms(), encode_time_ms);
    154       }
    155     }
    156   }
    157   // We're done!
    158   if (capture_time != -1) {
    159     overuse_detector_->FrameSent(capture_time);
    160   }
    161   return true;
    162 }
    163 
    164 }  // namespace internal
    165 }  // namespace webrtc
    166