H264 HW encode using VideoToolbox

media/base/mac/videotoolbox_glue.h

 // 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.
 
 #ifndef MEDIA_BASE_MAC_VIDEOTOOLBOX_GLUE_H_
 #define MEDIA_BASE_MAC_VIDEOTOOLBOX_GLUE_H_
 
 #include <stdint.h>
 
 #include "base/macros.h"
 #include "media/base/mac/coremedia_glue.h"
 #include "media/base/media_export.h"
 
 // VideoToolbox API is available in OS X 10.9 and iOS 8 (10.8 has support for
 // software encoding, but this class exposes the 10.9 API level). Chromium
 // requires OS X 10.6 or iOS 6. Linking with VideoToolbox therefore has to

[sandersd (OOO until July 31), 2016/03/09 22:42:08]

This comment is out of date now. In fact we are just waiting for the build SDK
bump so that we can delete this glue file. Unless iOS is still at 6?

(https://bugs.chromium.org/p/chromium/issues/detail?id=579648)

[emircan, 2016/03/09 23:29:34]

Thanks for the heads up. I updated the comment and referenced the bug. 

 // happen at runtime. This class is defined to try and load the VideoToolbox
 // library. If it succeeds, clients can use VideoToolbox via this class.
 class MEDIA_EXPORT VideoToolboxGlue {
  public:
   class Loader;
 
   // Returns a glue object if VideoToolbox is supported or null otherwise.
   // Using a glue object allows to avoid expensive atomic operations on every
   // function call. The object has process life duration and must not be
   // deleted.
@@ skipping 15 matching lines @@
       VTEncodeInfoFlags infoFlags,
       CoreMediaGlue::CMSampleBufferRef sampleBuffer);
 
   // Originally from VTSession.h
   typedef CFTypeRef VTSessionRef;
 
   // Originally from VTCompressionProperties.h
   CFStringRef kVTCompressionPropertyKey_AllowFrameReordering() const;
   CFStringRef kVTCompressionPropertyKey_AverageBitRate() const;
   CFStringRef kVTCompressionPropertyKey_ColorPrimaries() const;
+  CFStringRef kVTCompressionPropertyKey_DataRateLimits() const;
   CFStringRef kVTCompressionPropertyKey_ExpectedFrameRate() const;
   CFStringRef kVTCompressionPropertyKey_MaxFrameDelayCount() const;
   CFStringRef kVTCompressionPropertyKey_MaxKeyFrameInterval() const;
   CFStringRef kVTCompressionPropertyKey_MaxKeyFrameIntervalDuration() const;
   CFStringRef kVTCompressionPropertyKey_ProfileLevel() const;
   CFStringRef kVTCompressionPropertyKey_RealTime() const;
   CFStringRef kVTCompressionPropertyKey_TransferFunction() const;
   CFStringRef kVTCompressionPropertyKey_YCbCrMatrix() const;
 
   CFStringRef kVTEncodeFrameOptionKey_ForceKeyFrame() const;
 
   CFStringRef kVTProfileLevel_H264_Baseline_AutoLevel() const;
   CFStringRef kVTProfileLevel_H264_Main_AutoLevel() const;
   CFStringRef kVTProfileLevel_H264_Extended_AutoLevel() const;
   CFStringRef kVTProfileLevel_H264_High_AutoLevel() const;
 
   CFStringRef
       kVTVideoEncoderSpecification_EnableHardwareAcceleratedVideoEncoder()
       const;
+  CFStringRef
+  kVTVideoEncoderSpecification_RequireHardwareAcceleratedVideoEncoder() const;
 
   // Originally from VTCompressionSession.h
   OSStatus VTCompressionSessionCreate(
       CFAllocatorRef allocator,
       int32_t width,
       int32_t height,
       CoreMediaGlue::CMVideoCodecType codecType,
       CFDictionaryRef encoderSpecification,
       CFDictionaryRef sourceImageBufferAttributes,
       CFAllocatorRef compressedDataAllocator,
@@ skipping 21 matching lines @@
                                 CFTypeRef propertyValue) const;
 
  private:
   struct Library;
   VideoToolboxGlue();
   Library* library_;
   DISALLOW_COPY_AND_ASSIGN(VideoToolboxGlue);
 };
 
 #endif  // MEDIA_BASE_MAC_VIDEOTOOLBOX_GLUE_H_