Injectable Obj-C video codecs

webrtc/sdk/objc/Framework/Classes/PeerConnection/RTCVideoCodecH264.mm

+/*
+ *  Copyright 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.
+ */
+
+#import "WebRTC/RTCVideoCodecH264.h"
+
+#include <vector>
+
+#import "RTCVideoCodec+Private.h"
+#import "WebRTC/RTCVideoCodec.h"
+#import "WebRTC/RTCVideoFrame.h"
+#import "WebRTC/RTCVideoFrameBuffer.h"
+
+#include "webrtc/base/timeutils.h"
+#include "webrtc/sdk/objc/Framework/Classes/Video/objc_frame_buffer.h"
+#include "webrtc/sdk/objc/Framework/Classes/VideoToolbox/decoder.h"
+#include "webrtc/sdk/objc/Framework/Classes/VideoToolbox/encoder.h"
+#include "webrtc/system_wrappers/include/field_trial.h"
+
+const size_t kDefaultPayloadSize = 1440;
+
+const char kHighProfileExperiment[] = "WebRTC-H264HighProfile";
+
+bool IsHighProfileEnabled() {
+  return webrtc::field_trial::IsEnabled(kHighProfileExperiment);
+}
+
+// H264 specific settings.
+@implementation RTCCodecSpecificInfoH264
+
+@synthesize packetizationMode = _packetizationMode;
+
+- (webrtc::CodecSpecificInfo)toCpp {
+  webrtc::CodecSpecificInfo codecSpecificInfo;
+  codecSpecificInfo.codecType = webrtc::kVideoCodecH264;
+  codecSpecificInfo.codec_name = "H264";
+  codecSpecificInfo.codecSpecific.H264.packetization_mode =
+      (webrtc::H264PacketizationMode)_packetizationMode;
+
+  return codecSpecificInfo;
+}
+
+@end
+
+namespace {
+
+class H264VideoToolboxEncodeCompleteCallback : public webrtc::EncodedImageCallback {
+ public:
+  Result OnEncodedImage(const webrtc::EncodedImage &encoded_image,
+                        const webrtc::CodecSpecificInfo *codec_specific_info,
+                        const webrtc::RTPFragmentationHeader *fragmentation) {
+    RTCEncodedImage *image = [[RTCEncodedImage alloc] initWithEncodedImage:encoded_image];
+
+    RTCCodecSpecificInfoH264 *info = [[RTCCodecSpecificInfoH264 alloc] init];
+    info.packetizationMode =
+        (RTCH264PacketizationMode)codec_specific_info->codecSpecific.H264.packetization_mode;
+
+    RTCRtpFragmentationHeader *header =
+        [[RTCRtpFragmentationHeader alloc] initWithFragmentationHeader:fragmentation];
+
+    callback(image, info, header);
+    return Result(Result::OK, 0);
+  }
+
+  RTCVideoEncoderCallback callback;
+};
+
+class H264VideoToolboxDecodeCompleteCallback : public webrtc::DecodedImageCallback {
+ public:
+  int32_t Decoded(webrtc::VideoFrame &decodedImage) {
+    rtc::scoped_refptr<webrtc::VideoFrameBuffer> video_frame_buffer =
+        decodedImage.video_frame_buffer();
+    id<RTCVideoFrameBuffer> rtcFrameBuffer;
+    rtc::scoped_refptr<webrtc::ObjCFrameBuffer> objc_frame_buffer(
+        static_cast<webrtc::ObjCFrameBuffer *>(video_frame_buffer.get()));
+    rtcFrameBuffer = (id<RTCVideoFrameBuffer>)objc_frame_buffer->wrapped_frame_buffer();
+
+    RTCVideoFrame *videoFrame = [[RTCVideoFrame alloc]
+        initWithBuffer:rtcFrameBuffer
+              rotation:static_cast<RTCVideoRotation>(decodedImage.rotation())
+           timeStampNs:decodedImage.timestamp_us() * rtc::kNumNanosecsPerMicrosec];
+    videoFrame.timeStamp = decodedImage.timestamp();
+
+    callback(videoFrame);
+
+    return 0;
+  }
+
+  RTCVideoDecoderCallback callback;
+};
+
+}  // namespace
+
+// Encoder.
+@implementation RTCVideoEncoderH264 {
+  webrtc::H264VideoToolboxEncoder *_videoToolboxEncoder;
+  H264VideoToolboxEncodeCompleteCallback *_toolboxCallback;
+}
+
+- (instancetype)initWithCodecInfo:(RTCVideoCodecInfo *)codecInfo {
+  if (self = [super init]) {
+    cricket::VideoCodec codec = [codecInfo toCpp];
+    _videoToolboxEncoder = new webrtc::H264VideoToolboxEncoder(codec);
+  }
+  return self;
+}
+
+- (void)setCallback:(RTCVideoEncoderCallback)callback {
+  _toolboxCallback = new H264VideoToolboxEncodeCompleteCallback();
+  _toolboxCallback->callback = callback;
+  _videoToolboxEncoder->RegisterEncodeCompleteCallback(_toolboxCallback);
+}
+
+- (void)initEncodeWithSettings:(RTCVideoEncoderSettings *)settings
+                 numberOfCores:(int)numberOfCores {
+  webrtc::VideoCodec *codecSettings = [settings toCpp];
+  _videoToolboxEncoder->InitEncode(codecSettings, numberOfCores, kDefaultPayloadSize);
+}
+
+- (void)releaseEncode {
+  _videoToolboxEncoder->Release();
+}
+
+- (void)encode:(RTCVideoFrame *)frame
+    codecSpecificInfo:(id<RTCCodecSpecificInfo>)info
+           frameTypes:(NSArray<NSNumber *> *)frameTypes {
+  rtc::scoped_refptr<webrtc::VideoFrameBuffer> frameBuffer =
+      new rtc::RefCountedObject<webrtc::ObjCFrameBuffer>(frame.buffer);
+  webrtc::VideoFrame videoFrame(frameBuffer,
+                                (webrtc::VideoRotation)frame.rotation,
+                                frame.timeStampNs / rtc::kNumNanosecsPerMicrosec);
+  videoFrame.set_timestamp(frame.timeStamp);
+
+  // Handle types than can be converted into one of webrtc::CodecSpecificInfo's hard coded cases.
+  webrtc::CodecSpecificInfo codecSpecificInfo;
+  if ([info isKindOfClass:[RTCCodecSpecificInfoH264 class]]) {
+    codecSpecificInfo = [(RTCCodecSpecificInfoH264 *)info toCpp];
+  }
+
+  std::vector<webrtc::FrameType> nativeFrameTypes;
+  for (NSNumber *frameType in frameTypes) {
+    RTCFrameType rtcFrameType = (RTCFrameType)frameType.unsignedIntegerValue;
+    nativeFrameTypes.push_back((webrtc::FrameType)rtcFrameType);
+  }
+
+  _videoToolboxEncoder->Encode(videoFrame, &codecSpecificInfo, &nativeFrameTypes);
+}
+
+- (BOOL)setBitrate:(uint32_t)bitrateKbit framerate:(uint32_t)framerate {
+  return _videoToolboxEncoder->SetRates(bitrateKbit, framerate) == WEBRTC_VIDEO_CODEC_OK;
+}
+
+@end
+
+// Decoder.
+@implementation RTCVideoDecoderH264 {
+  webrtc::H264VideoToolboxDecoder *_videoToolboxDecoder;
+  H264VideoToolboxDecodeCompleteCallback *_toolboxCallback;
+}
+
+- (instancetype)init {
+  if (self = [super init]) {
+    cricket::VideoCodec codec(cricket::kH264CodecName);
+    _videoToolboxDecoder = new webrtc::H264VideoToolboxDecoder();
+  }
+  return self;
+}
+
+- (int)initDecodeWithSettings:(RTCVideoEncoderSettings *)settings numberOfCores:(int)numberOfCores {
+  webrtc::VideoCodec *codecSettings = [settings toCpp];
+  return _videoToolboxDecoder->InitDecode(codecSettings, numberOfCores);
+}
+
+- (void)setCallback:(RTCVideoDecoderCallback)callback {
+  _toolboxCallback = new H264VideoToolboxDecodeCompleteCallback();
+  _toolboxCallback->callback = callback;
+  _videoToolboxDecoder->RegisterDecodeCompleteCallback(_toolboxCallback);
+}
+
+- (int32_t)releaseDecode {
+  return _videoToolboxDecoder->Release();
+}
+
+- (int)decode:(RTCEncodedImage *)encodedImage
+          missingFrames:(BOOL)missingFrames
+    fragmentationHeader:(RTCRtpFragmentationHeader *)fragmentationHeader
+      codecSpecificInfo:(__nullable id<RTCCodecSpecificInfo>)info
+           renderTimeMs:(int64_t)renderTimeMs {
+  webrtc::EncodedImage image = [encodedImage toCpp];
+
+  // Handle types than can be converted into one of webrtc::CodecSpecificInfo's hard coded cases.
+  webrtc::CodecSpecificInfo codecSpecificInfo;
+  if ([info isKindOfClass:[RTCCodecSpecificInfoH264 class]]) {
+    codecSpecificInfo = [(RTCCodecSpecificInfoH264 *)info toCpp];
+  }
+
+  webrtc::RTPFragmentationHeader *header = [fragmentationHeader toCpp];
+
+  return _videoToolboxDecoder->Decode(
+      image, missingFrames, header, &codecSpecificInfo, renderTimeMs);
+}
+
+@end
+
+// Encoder factory.
+@implementation RTCVideoEncoderFactoryH264
+
+- (NSArray<RTCVideoCodecInfo *> *)supportedCodecs {
+  NSMutableArray<RTCVideoCodecInfo *> *codecs = [NSMutableArray array];
+  NSString *codecName = [NSString stringWithUTF8String:cricket::kH264CodecName];
+
+  if (IsHighProfileEnabled()) {
+    NSDictionary<NSString *, NSString *> *constrainedHighParams = @{
+      @"profile-level-id" : @"640c1f",  // Level 3.1 Constrained High.
+      @"level-asymmetry-allowed" : @"1",
+      @"packetization-mode" : @"1",
+    };
+    RTCVideoCodecInfo *constrainedHighInfo =
+        [[RTCVideoCodecInfo alloc] initWithPayload:0
+                                              name:codecName
+                                        parameters:constrainedHighParams];
+    [codecs addObject:constrainedHighInfo];
+  }
+
+  NSDictionary<NSString *, NSString *> *constrainedBaselineParams = @{
+    @"profile-level-id" : @"42e01f",  // Level 3.1 Constrained Baseline.
+    @"level-asymmetry-allowed" : @"1",
+    @"packetization-mode" : @"1",
+  };
+  RTCVideoCodecInfo *constrainedBaselineInfo =
+      [[RTCVideoCodecInfo alloc] initWithPayload:0
+                                            name:codecName
+                                      parameters:constrainedBaselineParams];
+  [codecs addObject:constrainedBaselineInfo];
+
+  return [codecs copy];
+}
+
+- (id<RTCVideoEncoder>)createEncoder:(RTCVideoCodecInfo *)info {
+  return [[RTCVideoEncoderH264 alloc] initWithCodecInfo:info];
+}
+
+@end
+
+// Decoder factory.
+@implementation RTCVideoDecoderFactoryH264
+
+- (id<RTCVideoDecoder>)createDecoder:(RTCVideoCodecInfo *)info {
+  return [[RTCVideoDecoderH264 alloc] init];
+}
+
+- (NSArray<RTCVideoCodecInfo *> *)supportedCodecs {
+  NSString *codecName = [NSString stringWithUTF8String:cricket::kH264CodecName];
+  return @[ [[RTCVideoCodecInfo alloc] initWithPayload:0 name:codecName parameters:@{}] ];
+}
+
+@end