Add framerate to VideoSinkWants and ability to signal on overuse

webrtc/test/video_capturer.cc

+/*
+ *  Copyright (c) 2017 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/test/video_capturer.h"
+
+#include "webrtc/base/basictypes.h"
+#include "webrtc/base/constructormagic.h"
+
+namespace webrtc {
+namespace test {
+VideoCapturer::VideoCapturer() : video_adapter_(new cricket::VideoAdapter()) {}
+VideoCapturer::~VideoCapturer() {}
+
+rtc::Optional<VideoFrame> VideoCapturer::AdaptFrame(const VideoFrame& frame) {
+  int cropped_width = 0;
+  int cropped_height = 0;
+  int out_width = 0;
+  int out_height = 0;
+
+  if (!video_adapter_->AdaptFrameResolution(
+          frame.width(), frame.height(), frame.timestamp_us() * 1000,
+          &cropped_width, &cropped_height, &out_width, &out_height)) {
+    // Drop frame in order to respect frame rate constraint.
+    return rtc::Optional<VideoFrame>();
+  }
+
+  rtc::Optional<VideoFrame> out_frame;
+  if (out_height != frame.height() || out_width != frame.width()) {
+    // Video adapter has requested a down-scale. Allocate a new buffer and
+    // return scaled version.
+    rtc::scoped_refptr<I420Buffer> scaled_buffer =
+        I420Buffer::Create(out_width, out_height);
+    scaled_buffer->ScaleFrom(*frame.video_frame_buffer().get());
+    out_frame.emplace(
+        VideoFrame(scaled_buffer, kVideoRotation_0, frame.timestamp_us()));
+  } else {
+    // No adaptations needed, just return the frame as is.
+    out_frame.emplace(frame);
+  }
+
+  return out_frame;
+}
+
+void VideoCapturer::AddOrUpdateSink(rtc::VideoSinkInterface<VideoFrame>* sink,
+                                    const rtc::VideoSinkWants& wants) {
+  video_adapter_->OnResolutionFramerateRequest(
+      wants.target_pixel_count, wants.max_pixel_count, wants.max_framerate_fps);
+}
+
+}  // namespace test
+}  // namespace webrtc