[cast] Add optional VideoEncoder method to flush frames.

media/cast/sender/h264_vt_encoder.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/cast/sender/h264_vt_encoder.h"
 
 #include <string>
 #include <vector>
 
 #include "base/big_endian.h"
@@ skipping 317 matching lines @@
       video_config.max_frame_rate);
   SetSessionProperty(
       videotoolbox_glue_->kVTCompressionPropertyKey_ColorPrimaries(),
       kCVImageBufferColorPrimaries_ITU_R_709_2);
   SetSessionProperty(
       videotoolbox_glue_->kVTCompressionPropertyKey_TransferFunction(),
       kCVImageBufferTransferFunction_ITU_R_709_2);
   SetSessionProperty(
       videotoolbox_glue_->kVTCompressionPropertyKey_YCbCrMatrix(),
       kCVImageBufferYCbCrMatrix_ITU_R_709_2);
+  if (video_config.max_number_of_video_buffers_used > 0) {
+    SetSessionProperty(
+        videotoolbox_glue_->kVTCompressionPropertyKey_MaxFrameDelayCount(),
+        video_config.max_number_of_video_buffers_used);
+  }
 }
 
 void H264VideoToolboxEncoder::Teardown() {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   // If the compression session exists, invalidate it. This blocks until all
   // pending output callbacks have returned and any internal threads have
   // joined, ensuring no output callback ever sees a dangling encoder pointer.
   if (compression_session_) {
     videotoolbox_glue_->VTCompressionSessionInvalidate(compression_session_);
@@ skipping 75 matching lines @@
 scoped_ptr<VideoFrameFactory>
 H264VideoToolboxEncoder::CreateVideoFrameFactory() {
   base::ScopedCFTypeRef<CVPixelBufferPoolRef> pool(
       videotoolbox_glue_->VTCompressionSessionGetPixelBufferPool(
           compression_session_),
       base::scoped_policy::RETAIN);
   return scoped_ptr<VideoFrameFactory>(
       new VideoFrameFactoryCVPixelBufferPoolImpl(pool));
 }
 
+void H264VideoToolboxEncoder::EmitFrames() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  if (!compression_session_) {
+    DLOG(ERROR) << " compression session is null";
+    return;
+  }
+
+  OSStatus status = videotoolbox_glue_->VTCompressionSessionCompleteFrames(
+      compression_session_, CoreMediaGlue::CMTime{0, 0, 0, 0});
+  if (status != noErr) {
+    DLOG(ERROR) << " VTCompressionSessionCompleteFrames failed: " << status;
+  }
+}
+
 bool H264VideoToolboxEncoder::SetSessionProperty(CFStringRef key,
                                                  int32_t value) {
   base::ScopedCFTypeRef<CFNumberRef> cfvalue(
       CFNumberCreate(nullptr, kCFNumberSInt32Type, &value));
   return videotoolbox_glue_->VTSessionSetProperty(compression_session_, key,
                                                   cfvalue) == noErr;
 }
 
 bool H264VideoToolboxEncoder::SetSessionProperty(CFStringRef key, bool value) {
   CFBooleanRef cfvalue = (value) ? kCFBooleanTrue : kCFBooleanFalse;
@@ skipping 62 matching lines @@
   CopySampleBufferToAnnexBBuffer(sbuf, &encoded_frame->data, keyframe);
 
   encoder->cast_environment_->PostTask(
       CastEnvironment::MAIN, FROM_HERE,
       base::Bind(request->frame_encoded_callback,
                  base::Passed(&encoded_frame)));
 }
 
 }  // namespace cast
 }  // namespace media