| /* |
| * Copyright (c) 2016 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 "media/base/video_broadcaster.h" |
| |
| #include <vector> |
| |
| #include "absl/types/optional.h" |
| #include "api/video/i420_buffer.h" |
| #include "api/video/video_rotation.h" |
| #include "media/base/video_common.h" |
| #include "rtc_base/checks.h" |
| #include "rtc_base/logging.h" |
| |
| namespace rtc { |
| |
| VideoBroadcaster::VideoBroadcaster() = default; |
| VideoBroadcaster::~VideoBroadcaster() = default; |
| |
| void VideoBroadcaster::AddOrUpdateSink( |
| VideoSinkInterface<webrtc::VideoFrame>* sink, |
| const VideoSinkWants& wants) { |
| RTC_DCHECK(sink != nullptr); |
| rtc::CritScope cs(&sinks_and_wants_lock_); |
| if (!FindSinkPair(sink)) { |
| // |Sink| is a new sink, which didn't receive previous frame. |
| previous_frame_sent_to_all_sinks_ = false; |
| } |
| VideoSourceBase::AddOrUpdateSink(sink, wants); |
| UpdateWants(); |
| } |
| |
| void VideoBroadcaster::RemoveSink( |
| VideoSinkInterface<webrtc::VideoFrame>* sink) { |
| RTC_DCHECK(sink != nullptr); |
| rtc::CritScope cs(&sinks_and_wants_lock_); |
| VideoSourceBase::RemoveSink(sink); |
| UpdateWants(); |
| } |
| |
| bool VideoBroadcaster::frame_wanted() const { |
| rtc::CritScope cs(&sinks_and_wants_lock_); |
| return !sink_pairs().empty(); |
| } |
| |
| VideoSinkWants VideoBroadcaster::wants() const { |
| rtc::CritScope cs(&sinks_and_wants_lock_); |
| return current_wants_; |
| } |
| |
| void VideoBroadcaster::OnFrame(const webrtc::VideoFrame& frame) { |
| rtc::CritScope cs(&sinks_and_wants_lock_); |
| bool current_frame_was_discarded = false; |
| for (auto& sink_pair : sink_pairs()) { |
| if (sink_pair.wants.rotation_applied && |
| frame.rotation() != webrtc::kVideoRotation_0) { |
| // Calls to OnFrame are not synchronized with changes to the sink wants. |
| // When rotation_applied is set to true, one or a few frames may get here |
| // with rotation still pending. Protect sinks that don't expect any |
| // pending rotation. |
| RTC_LOG(LS_VERBOSE) << "Discarding frame with unexpected rotation."; |
| sink_pair.sink->OnDiscardedFrame(); |
| current_frame_was_discarded = true; |
| continue; |
| } |
| if (sink_pair.wants.black_frames) { |
| webrtc::VideoFrame black_frame = |
| webrtc::VideoFrame::Builder() |
| .set_video_frame_buffer( |
| GetBlackFrameBuffer(frame.width(), frame.height())) |
| .set_rotation(frame.rotation()) |
| .set_timestamp_us(frame.timestamp_us()) |
| .set_id(frame.id()) |
| .build(); |
| sink_pair.sink->OnFrame(black_frame); |
| } else if (!previous_frame_sent_to_all_sinks_ && frame.has_update_rect()) { |
| // Since last frame was not sent to some sinks, no reliable update |
| // information is available, so we need to clear the update rect. |
| webrtc::VideoFrame copy = frame; |
| copy.clear_update_rect(); |
| sink_pair.sink->OnFrame(copy); |
| } else { |
| sink_pair.sink->OnFrame(frame); |
| } |
| } |
| previous_frame_sent_to_all_sinks_ = !current_frame_was_discarded; |
| } |
| |
| void VideoBroadcaster::OnDiscardedFrame() { |
| for (auto& sink_pair : sink_pairs()) { |
| sink_pair.sink->OnDiscardedFrame(); |
| } |
| } |
| |
| void VideoBroadcaster::UpdateWants() { |
| VideoSinkWants wants; |
| wants.rotation_applied = false; |
| wants.resolution_alignment = 1; |
| for (auto& sink : sink_pairs()) { |
| // wants.rotation_applied == ANY(sink.wants.rotation_applied) |
| if (sink.wants.rotation_applied) { |
| wants.rotation_applied = true; |
| } |
| // wants.max_pixel_count == MIN(sink.wants.max_pixel_count) |
| if (sink.wants.max_pixel_count < wants.max_pixel_count) { |
| wants.max_pixel_count = sink.wants.max_pixel_count; |
| } |
| // Select the minimum requested target_pixel_count, if any, of all sinks so |
| // that we don't over utilize the resources for any one. |
| // TODO(sprang): Consider using the median instead, since the limit can be |
| // expressed by max_pixel_count. |
| if (sink.wants.target_pixel_count && |
| (!wants.target_pixel_count || |
| (*sink.wants.target_pixel_count < *wants.target_pixel_count))) { |
| wants.target_pixel_count = sink.wants.target_pixel_count; |
| } |
| // Select the minimum for the requested max framerates. |
| if (sink.wants.max_framerate_fps < wants.max_framerate_fps) { |
| wants.max_framerate_fps = sink.wants.max_framerate_fps; |
| } |
| wants.resolution_alignment = cricket::LeastCommonMultiple( |
| wants.resolution_alignment, sink.wants.resolution_alignment); |
| } |
| |
| if (wants.target_pixel_count && |
| *wants.target_pixel_count >= wants.max_pixel_count) { |
| wants.target_pixel_count.emplace(wants.max_pixel_count); |
| } |
| current_wants_ = wants; |
| } |
| |
| const rtc::scoped_refptr<webrtc::VideoFrameBuffer>& |
| VideoBroadcaster::GetBlackFrameBuffer(int width, int height) { |
| if (!black_frame_buffer_ || black_frame_buffer_->width() != width || |
| black_frame_buffer_->height() != height) { |
| rtc::scoped_refptr<webrtc::I420Buffer> buffer = |
| webrtc::I420Buffer::Create(width, height); |
| webrtc::I420Buffer::SetBlack(buffer.get()); |
| black_frame_buffer_ = buffer; |
| } |
| |
| return black_frame_buffer_; |
| } |
| |
| } // namespace rtc |