Add framerate to VideoSinkWants and ability to signal on overuse

webrtc/test/frame_generator_capturer.cc

Index: webrtc/test/frame_generator_capturer.cc
diff --git a/webrtc/test/frame_generator_capturer.cc b/webrtc/test/frame_generator_capturer.cc
index 00efbc8b40b467e2248169349ac498997b8de3d2..f0b205624a58ad45d966ecae7588ad393c9f680b 100644
--- a/webrtc/test/frame_generator_capturer.cc
+++ b/webrtc/test/frame_generator_capturer.cc
@@ -10,8 +10,10 @@
 
 #include "webrtc/test/frame_generator_capturer.h"
 
+#include "webrtc/api/video/i420_buffer.h"
 #include "webrtc/base/criticalsection.h"
 #include "webrtc/base/platform_thread.h"
+#include "webrtc/media/base/videoadapter.h"
 #include "webrtc/system_wrappers/include/clock.h"
 #include "webrtc/system_wrappers/include/event_wrapper.h"
 #include "webrtc/system_wrappers/include/sleep.h"
@@ -64,6 +66,7 @@ FrameGeneratorCapturer::FrameGeneratorCapturer(
       tick_(EventTimerWrapper::Create()),
       thread_(FrameGeneratorCapturer::Run, this, "FrameGeneratorCapturer"),
       frame_generator_(std::move(frame_generator)),
+      video_adpter_(new cricket::VideoAdapter()),
       target_fps_(target_fps),
       first_frame_capture_time_(-1) {
   RTC_DCHECK(frame_generator_);
@@ -87,8 +90,10 @@ bool FrameGeneratorCapturer::Init() {
   if (frame_generator_.get() == NULL)
     return false;
 
-  if (!tick_->StartTimer(true, 1000 / target_fps_))
-    return false;
+  {
+    rtc::CritScope cs(&lock_);
+    RTC_DCHECK(tick_->StartTimer(false, 1000 / target_fps_));
+  }
   thread_.Start();
   thread_.SetPriority(rtc::kHighPriority);
   return true;
@@ -100,6 +105,8 @@ bool FrameGeneratorCapturer::Run(void* obj) {
 }
 
 void FrameGeneratorCapturer::InsertFrame() {
+  int64_t start_tims_ms = rtc::TimeMillis();
+  int64_t sleep_time_ms;

[kthelgason, 2017/03/14 10:01:20]

can this be initialized here, rather than further down in the method?

[sprang_webrtc, 2017/03/14 14:15:02]

Need to hold the lock then, so made sense to me to do it closer to where it's
used below, no?

   {
     rtc::CritScope cs(&lock_);
     if (sending_) {
@@ -109,11 +116,40 @@ void FrameGeneratorCapturer::InsertFrame() {
       if (first_frame_capture_time_ == -1) {
         first_frame_capture_time_ = frame->ntp_time_ms();
       }
-      if (sink_)
-        sink_->OnFrame(*frame);
+
+      if (sink_) {
+        int cropped_width = 0;
+        int cropped_height = 0;

[kthelgason, 2017/03/14 10:01:20]

these look unused

[sprang_webrtc, 2017/03/14 14:15:02]

They're out params from video_adpter_->AdaptFrameResolution().
I guess I can get away with just the one, but not sure it helps readability?

+        int out_width = 0;
+        int out_height = 0;
+        video_adpter_->AdaptFrameResolution(
+            frame->width(), frame->height(), frame->timestamp_us() * 1000,
+            &cropped_width, &cropped_height, &out_width, &out_height);
+
+        if (out_height != frame->height() || out_width != frame->width()) {
+          rtc::scoped_refptr<I420Buffer> scaled_buffer =
+              I420Buffer::Create(out_width, out_height);
+          scaled_buffer->ScaleFrom(*frame->video_frame_buffer().get());
+          VideoFrame adapted_frame(scaled_buffer, kVideoRotation_0,
+                                   frame->timestamp_us());
+          sink_->OnFrame(adapted_frame);
+        } else {
+          sink_->OnFrame(*frame);
+        }
+      }
+    }
+
+    if (wanted_fps_) {
+      sleep_time_ms = 1000 / *wanted_fps_;
+    } else {
+      sleep_time_ms = 1000 / target_fps_;
     }
   }
-  tick_->Wait(WEBRTC_EVENT_INFINITE);
+
+  int64_t correction_delta = rtc::TimeMillis() - start_tims_ms;
+  sleep_time_ms -= correction_delta;
+  if (sleep_time_ms > 0)
+    tick_->Wait(sleep_time_ms);

[kthelgason, 2017/03/14 10:01:20]

the use of `tick` is behind a lock in `Init` but not here. Is the lock
necessary?

[sprang_webrtc, 2017/03/14 14:15:02]

The lock is for |target_fps_|, not |tick_|.

 }
 
 void FrameGeneratorCapturer::Start() {
@@ -145,6 +181,10 @@ void FrameGeneratorCapturer::AddOrUpdateSink(
   sink_ = sink;
   if (sink_wants_observer_)
     sink_wants_observer_->OnSinkWantsChanged(sink, wants);
+
+  video_adpter_->OnResolutionFramerateRequest(
+      wants.target_pixel_count, wants.max_pixel_count, rtc::Optional<int>());
+  wanted_fps_ = wants.max_framerate_fps;
 }
 
 void FrameGeneratorCapturer::RemoveSink(