| /* |
| * Copyright (c) 2015 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" |
| |
| #import <VideoToolbox/VideoToolbox.h> |
| #include <vector> |
| |
| #if defined(WEBRTC_IOS) |
| #import "Common/RTCUIApplicationStatusObserver.h" |
| #import "WebRTC/UIDevice+RTCDevice.h" |
| #endif |
| #import "PeerConnection/RTCVideoCodec+Private.h" |
| #import "WebRTC/RTCVideoCodec.h" |
| #import "WebRTC/RTCVideoFrame.h" |
| #import "WebRTC/RTCVideoFrameBuffer.h" |
| #import "helpers.h" |
| #include "libyuv/convert_from.h" |
| #include "webrtc/common_video/h264/h264_bitstream_parser.h" |
| #include "webrtc/common_video/h264/profile_level_id.h" |
| #include "webrtc/common_video/include/bitrate_adjuster.h" |
| #include "webrtc/modules/include/module_common_types.h" |
| #include "webrtc/modules/video_coding/include/video_error_codes.h" |
| #include "webrtc/rtc_base/buffer.h" |
| #include "webrtc/rtc_base/logging.h" |
| #include "webrtc/rtc_base/timeutils.h" |
| #include "webrtc/sdk/objc/Framework/Classes/VideoToolbox/nalu_rewriter.h" |
| #include "webrtc/system_wrappers/include/clock.h" |
| |
| @interface RTCVideoEncoderH264 () |
| |
| - (void)frameWasEncoded:(OSStatus)status |
| flags:(VTEncodeInfoFlags)infoFlags |
| sampleBuffer:(CMSampleBufferRef)sampleBuffer |
| codecSpecificInfo:(id<RTCCodecSpecificInfo>)codecSpecificInfo |
| width:(int32_t)width |
| height:(int32_t)height |
| renderTimeMs:(int64_t)renderTimeMs |
| timestamp:(uint32_t)timestamp |
| rotation:(RTCVideoRotation)rotation; |
| |
| @end |
| |
| // The ratio between kVTCompressionPropertyKey_DataRateLimits and |
| // kVTCompressionPropertyKey_AverageBitRate. The data rate limit is set higher |
| // than the average bit rate to avoid undershooting the target. |
| const float kLimitToAverageBitRateFactor = 1.5f; |
| // These thresholds deviate from the default h264 QP thresholds, as they |
| // have been found to work better on devices that support VideoToolbox |
| const int kLowH264QpThreshold = 28; |
| const int kHighH264QpThreshold = 39; |
| |
| // Struct that we pass to the encoder per frame to encode. We receive it again |
| // in the encoder callback. |
| struct RTCFrameEncodeParams { |
| RTCFrameEncodeParams(RTCVideoEncoderH264 *e, |
| RTCCodecSpecificInfoH264 *csi, |
| int32_t w, |
| int32_t h, |
| int64_t rtms, |
| uint32_t ts, |
| RTCVideoRotation r) |
| : encoder(e), width(w), height(h), render_time_ms(rtms), timestamp(ts), rotation(r) { |
| if (csi) { |
| codecSpecificInfo = csi; |
| } else { |
| codecSpecificInfo = [[RTCCodecSpecificInfoH264 alloc] init]; |
| } |
| } |
| |
| RTCVideoEncoderH264 *encoder; |
| RTCCodecSpecificInfoH264 *codecSpecificInfo; |
| int32_t width; |
| int32_t height; |
| int64_t render_time_ms; |
| uint32_t timestamp; |
| RTCVideoRotation rotation; |
| }; |
| |
| // We receive I420Frames as input, but we need to feed CVPixelBuffers into the |
| // encoder. This performs the copy and format conversion. |
| // TODO(tkchin): See if encoder will accept i420 frames and compare performance. |
| bool CopyVideoFrameToPixelBuffer(id<RTCI420Buffer> frameBuffer, CVPixelBufferRef pixelBuffer) { |
| RTC_DCHECK(pixelBuffer); |
| RTC_DCHECK_EQ(CVPixelBufferGetPixelFormatType(pixelBuffer), |
| kCVPixelFormatType_420YpCbCr8BiPlanarFullRange); |
| RTC_DCHECK_EQ(CVPixelBufferGetHeightOfPlane(pixelBuffer, 0), frameBuffer.height); |
| RTC_DCHECK_EQ(CVPixelBufferGetWidthOfPlane(pixelBuffer, 0), frameBuffer.width); |
| |
| CVReturn cvRet = CVPixelBufferLockBaseAddress(pixelBuffer, 0); |
| if (cvRet != kCVReturnSuccess) { |
| LOG(LS_ERROR) << "Failed to lock base address: " << cvRet; |
| return false; |
| } |
| uint8_t *dstY = reinterpret_cast<uint8_t *>(CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 0)); |
| int dstStrideY = CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 0); |
| uint8_t *dstUV = reinterpret_cast<uint8_t *>(CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 1)); |
| int dstStrideUV = CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 1); |
| // Convert I420 to NV12. |
| int ret = libyuv::I420ToNV12(frameBuffer.dataY, |
| frameBuffer.strideY, |
| frameBuffer.dataU, |
| frameBuffer.strideU, |
| frameBuffer.dataV, |
| frameBuffer.strideV, |
| dstY, |
| dstStrideY, |
| dstUV, |
| dstStrideUV, |
| frameBuffer.width, |
| frameBuffer.height); |
| CVPixelBufferUnlockBaseAddress(pixelBuffer, 0); |
| if (ret) { |
| LOG(LS_ERROR) << "Error converting I420 VideoFrame to NV12 :" << ret; |
| return false; |
| } |
| return true; |
| } |
| |
| CVPixelBufferRef CreatePixelBuffer(CVPixelBufferPoolRef pixel_buffer_pool) { |
| if (!pixel_buffer_pool) { |
| LOG(LS_ERROR) << "Failed to get pixel buffer pool."; |
| return nullptr; |
| } |
| CVPixelBufferRef pixel_buffer; |
| CVReturn ret = CVPixelBufferPoolCreatePixelBuffer(nullptr, pixel_buffer_pool, &pixel_buffer); |
| if (ret != kCVReturnSuccess) { |
| LOG(LS_ERROR) << "Failed to create pixel buffer: " << ret; |
| // We probably want to drop frames here, since failure probably means |
| // that the pool is empty. |
| return nullptr; |
| } |
| return pixel_buffer; |
| } |
| |
| // This is the callback function that VideoToolbox calls when encode is |
| // complete. From inspection this happens on its own queue. |
| void compressionOutputCallback(void *encoder, |
| void *params, |
| OSStatus status, |
| VTEncodeInfoFlags infoFlags, |
| CMSampleBufferRef sampleBuffer) { |
| std::unique_ptr<RTCFrameEncodeParams> encodeParams( |
| reinterpret_cast<RTCFrameEncodeParams *>(params)); |
| [encodeParams->encoder frameWasEncoded:status |
| flags:infoFlags |
| sampleBuffer:sampleBuffer |
| codecSpecificInfo:encodeParams->codecSpecificInfo |
| width:encodeParams->width |
| height:encodeParams->height |
| renderTimeMs:encodeParams->render_time_ms |
| timestamp:encodeParams->timestamp |
| rotation:encodeParams->rotation]; |
| } |
| |
| // Extract VideoToolbox profile out of the cricket::VideoCodec. If there is no |
| // specific VideoToolbox profile for the specified level, AutoLevel will be |
| // returned. The user must initialize the encoder with a resolution and |
| // framerate conforming to the selected H264 level regardless. |
| CFStringRef ExtractProfile(const cricket::VideoCodec &codec) { |
| const rtc::Optional<webrtc::H264::ProfileLevelId> profile_level_id = |
| webrtc::H264::ParseSdpProfileLevelId(codec.params); |
| RTC_DCHECK(profile_level_id); |
| switch (profile_level_id->profile) { |
| case webrtc::H264::kProfileConstrainedBaseline: |
| case webrtc::H264::kProfileBaseline: |
| switch (profile_level_id->level) { |
| case webrtc::H264::kLevel3: |
| return kVTProfileLevel_H264_Baseline_3_0; |
| case webrtc::H264::kLevel3_1: |
| return kVTProfileLevel_H264_Baseline_3_1; |
| case webrtc::H264::kLevel3_2: |
| return kVTProfileLevel_H264_Baseline_3_2; |
| case webrtc::H264::kLevel4: |
| return kVTProfileLevel_H264_Baseline_4_0; |
| case webrtc::H264::kLevel4_1: |
| return kVTProfileLevel_H264_Baseline_4_1; |
| case webrtc::H264::kLevel4_2: |
| return kVTProfileLevel_H264_Baseline_4_2; |
| case webrtc::H264::kLevel5: |
| return kVTProfileLevel_H264_Baseline_5_0; |
| case webrtc::H264::kLevel5_1: |
| return kVTProfileLevel_H264_Baseline_5_1; |
| case webrtc::H264::kLevel5_2: |
| return kVTProfileLevel_H264_Baseline_5_2; |
| case webrtc::H264::kLevel1: |
| case webrtc::H264::kLevel1_b: |
| case webrtc::H264::kLevel1_1: |
| case webrtc::H264::kLevel1_2: |
| case webrtc::H264::kLevel1_3: |
| case webrtc::H264::kLevel2: |
| case webrtc::H264::kLevel2_1: |
| case webrtc::H264::kLevel2_2: |
| return kVTProfileLevel_H264_Baseline_AutoLevel; |
| } |
| |
| case webrtc::H264::kProfileMain: |
| switch (profile_level_id->level) { |
| case webrtc::H264::kLevel3: |
| return kVTProfileLevel_H264_Main_3_0; |
| case webrtc::H264::kLevel3_1: |
| return kVTProfileLevel_H264_Main_3_1; |
| case webrtc::H264::kLevel3_2: |
| return kVTProfileLevel_H264_Main_3_2; |
| case webrtc::H264::kLevel4: |
| return kVTProfileLevel_H264_Main_4_0; |
| case webrtc::H264::kLevel4_1: |
| return kVTProfileLevel_H264_Main_4_1; |
| case webrtc::H264::kLevel4_2: |
| return kVTProfileLevel_H264_Main_4_2; |
| case webrtc::H264::kLevel5: |
| return kVTProfileLevel_H264_Main_5_0; |
| case webrtc::H264::kLevel5_1: |
| return kVTProfileLevel_H264_Main_5_1; |
| case webrtc::H264::kLevel5_2: |
| return kVTProfileLevel_H264_Main_5_2; |
| case webrtc::H264::kLevel1: |
| case webrtc::H264::kLevel1_b: |
| case webrtc::H264::kLevel1_1: |
| case webrtc::H264::kLevel1_2: |
| case webrtc::H264::kLevel1_3: |
| case webrtc::H264::kLevel2: |
| case webrtc::H264::kLevel2_1: |
| case webrtc::H264::kLevel2_2: |
| return kVTProfileLevel_H264_Main_AutoLevel; |
| } |
| |
| case webrtc::H264::kProfileConstrainedHigh: |
| case webrtc::H264::kProfileHigh: |
| switch (profile_level_id->level) { |
| case webrtc::H264::kLevel3: |
| return kVTProfileLevel_H264_High_3_0; |
| case webrtc::H264::kLevel3_1: |
| return kVTProfileLevel_H264_High_3_1; |
| case webrtc::H264::kLevel3_2: |
| return kVTProfileLevel_H264_High_3_2; |
| case webrtc::H264::kLevel4: |
| return kVTProfileLevel_H264_High_4_0; |
| case webrtc::H264::kLevel4_1: |
| return kVTProfileLevel_H264_High_4_1; |
| case webrtc::H264::kLevel4_2: |
| return kVTProfileLevel_H264_High_4_2; |
| case webrtc::H264::kLevel5: |
| return kVTProfileLevel_H264_High_5_0; |
| case webrtc::H264::kLevel5_1: |
| return kVTProfileLevel_H264_High_5_1; |
| case webrtc::H264::kLevel5_2: |
| return kVTProfileLevel_H264_High_5_2; |
| case webrtc::H264::kLevel1: |
| case webrtc::H264::kLevel1_b: |
| case webrtc::H264::kLevel1_1: |
| case webrtc::H264::kLevel1_2: |
| case webrtc::H264::kLevel1_3: |
| case webrtc::H264::kLevel2: |
| case webrtc::H264::kLevel2_1: |
| case webrtc::H264::kLevel2_2: |
| return kVTProfileLevel_H264_High_AutoLevel; |
| } |
| } |
| } |
| |
| @implementation RTCVideoEncoderH264 { |
| RTCVideoCodecInfo *_codecInfo; |
| webrtc::BitrateAdjuster *_bitrateAdjuster; |
| uint32_t _targetBitrateBps; |
| uint32_t _encoderBitrateBps; |
| RTCH264PacketizationMode _packetizationMode; |
| CFStringRef _profile; |
| RTCVideoEncoderCallback _callback; |
| int32_t _width; |
| int32_t _height; |
| VTCompressionSessionRef _compressionSession; |
| RTCVideoCodecMode _mode; |
| |
| webrtc::H264BitstreamParser _h264BitstreamParser; |
| std::vector<uint8_t> _nv12ScaleBuffer; |
| } |
| |
| // .5 is set as a mininum to prevent overcompensating for large temporary |
| // overshoots. We don't want to degrade video quality too badly. |
| // .95 is set to prevent oscillations. When a lower bitrate is set on the |
| // encoder than previously set, its output seems to have a brief period of |
| // drastically reduced bitrate, so we want to avoid that. In steady state |
| // conditions, 0.95 seems to give us better overall bitrate over long periods |
| // of time. |
| - (instancetype)initWithCodecInfo:(RTCVideoCodecInfo *)codecInfo { |
| if (self = [super init]) { |
| _codecInfo = codecInfo; |
| _bitrateAdjuster = new webrtc::BitrateAdjuster(webrtc::Clock::GetRealTimeClock(), .5, .95); |
| _packetizationMode = RTCH264PacketizationModeNonInterleaved; |
| _profile = ExtractProfile([codecInfo nativeVideoCodec]); |
| LOG(LS_INFO) << "Using profile " << CFStringToString(_profile); |
| RTC_CHECK([codecInfo.name isEqualToString:@"H264"]); |
| } |
| return self; |
| } |
| |
| - (void)dealloc { |
| [self destroyCompressionSession]; |
| } |
| |
| - (NSInteger)startEncodeWithSettings:(RTCVideoEncoderSettings *)settings |
| numberOfCores:(int)numberOfCores { |
| RTC_DCHECK(settings); |
| RTC_DCHECK([settings.name isEqualToString:@"H264"]); |
| |
| _width = settings.width; |
| _height = settings.height; |
| _mode = settings.mode; |
| |
| // We can only set average bitrate on the HW encoder. |
| _targetBitrateBps = settings.startBitrate; |
| _bitrateAdjuster->SetTargetBitrateBps(_targetBitrateBps); |
| |
| // TODO(tkchin): Try setting payload size via |
| // kVTCompressionPropertyKey_MaxH264SliceBytes. |
| |
| return [self resetCompressionSession]; |
| } |
| |
| - (NSInteger)encode:(RTCVideoFrame *)frame |
| codecSpecificInfo:(id<RTCCodecSpecificInfo>)codecSpecificInfo |
| frameTypes:(NSArray<NSNumber *> *)frameTypes { |
| RTC_DCHECK_EQ(frame.width, _width); |
| RTC_DCHECK_EQ(frame.height, _height); |
| if (!_callback || !_compressionSession) { |
| return WEBRTC_VIDEO_CODEC_UNINITIALIZED; |
| } |
| #if defined(WEBRTC_IOS) |
| if (![[RTCUIApplicationStatusObserver sharedInstance] isApplicationActive]) { |
| // Ignore all encode requests when app isn't active. In this state, the |
| // hardware encoder has been invalidated by the OS. |
| return WEBRTC_VIDEO_CODEC_OK; |
| } |
| #endif |
| BOOL isKeyframeRequired = NO; |
| |
| // Get a pixel buffer from the pool and copy frame data over. |
| CVPixelBufferPoolRef pixelBufferPool = |
| VTCompressionSessionGetPixelBufferPool(_compressionSession); |
| |
| #if defined(WEBRTC_IOS) |
| if (!pixelBufferPool) { |
| // Kind of a hack. On backgrounding, the compression session seems to get |
| // invalidated, which causes this pool call to fail when the application |
| // is foregrounded and frames are being sent for encoding again. |
| // Resetting the session when this happens fixes the issue. |
| // In addition we request a keyframe so video can recover quickly. |
| [self resetCompressionSession]; |
| pixelBufferPool = VTCompressionSessionGetPixelBufferPool(_compressionSession); |
| isKeyframeRequired = YES; |
| LOG(LS_INFO) << "Resetting compression session due to invalid pool."; |
| } |
| #endif |
| |
| CVPixelBufferRef pixelBuffer = nullptr; |
| if ([frame.buffer isKindOfClass:[RTCCVPixelBuffer class]]) { |
| // Native frame buffer |
| RTCCVPixelBuffer *rtcPixelBuffer = (RTCCVPixelBuffer *)frame.buffer; |
| if (![rtcPixelBuffer requiresCropping]) { |
| // This pixel buffer might have a higher resolution than what the |
| // compression session is configured to. The compression session can |
| // handle that and will output encoded frames in the configured |
| // resolution regardless of the input pixel buffer resolution. |
| pixelBuffer = rtcPixelBuffer.pixelBuffer; |
| CVBufferRetain(pixelBuffer); |
| } else { |
| // Cropping required, we need to crop and scale to a new pixel buffer. |
| pixelBuffer = CreatePixelBuffer(pixelBufferPool); |
| if (!pixelBuffer) { |
| return WEBRTC_VIDEO_CODEC_ERROR; |
| } |
| int dstWidth = CVPixelBufferGetWidth(pixelBuffer); |
| int dstHeight = CVPixelBufferGetHeight(pixelBuffer); |
| if ([rtcPixelBuffer requiresScalingToWidth:dstWidth height:dstHeight]) { |
| int size = |
| [rtcPixelBuffer bufferSizeForCroppingAndScalingToWidth:dstWidth height:dstHeight]; |
| _nv12ScaleBuffer.resize(size); |
| } else { |
| _nv12ScaleBuffer.clear(); |
| } |
| _nv12ScaleBuffer.shrink_to_fit(); |
| if (![rtcPixelBuffer cropAndScaleTo:pixelBuffer withTempBuffer:_nv12ScaleBuffer.data()]) { |
| return WEBRTC_VIDEO_CODEC_ERROR; |
| } |
| } |
| } |
| |
| if (!pixelBuffer) { |
| // We did not have a native frame buffer |
| pixelBuffer = CreatePixelBuffer(pixelBufferPool); |
| if (!pixelBuffer) { |
| return WEBRTC_VIDEO_CODEC_ERROR; |
| } |
| RTC_DCHECK(pixelBuffer); |
| if (!CopyVideoFrameToPixelBuffer([frame.buffer toI420], pixelBuffer)) { |
| LOG(LS_ERROR) << "Failed to copy frame data."; |
| CVBufferRelease(pixelBuffer); |
| return WEBRTC_VIDEO_CODEC_ERROR; |
| } |
| } |
| |
| // Check if we need a keyframe. |
| if (!isKeyframeRequired && frameTypes) { |
| for (NSNumber *frameType in frameTypes) { |
| if ((RTCFrameType)frameType.intValue == RTCFrameTypeVideoFrameKey) { |
| isKeyframeRequired = YES; |
| break; |
| } |
| } |
| } |
| |
| CMTime presentationTimeStamp = CMTimeMake(frame.timeStampNs / rtc::kNumNanosecsPerMillisec, 1000); |
| CFDictionaryRef frameProperties = nullptr; |
| if (isKeyframeRequired) { |
| CFTypeRef keys[] = {kVTEncodeFrameOptionKey_ForceKeyFrame}; |
| CFTypeRef values[] = {kCFBooleanTrue}; |
| frameProperties = CreateCFTypeDictionary(keys, values, 1); |
| } |
| |
| std::unique_ptr<RTCFrameEncodeParams> encodeParams; |
| encodeParams.reset(new RTCFrameEncodeParams(self, |
| codecSpecificInfo, |
| _width, |
| _height, |
| frame.timeStampNs / rtc::kNumNanosecsPerMillisec, |
| frame.timeStamp, |
| frame.rotation)); |
| encodeParams->codecSpecificInfo.packetizationMode = _packetizationMode; |
| |
| // Update the bitrate if needed. |
| [self setBitrateBps:_bitrateAdjuster->GetAdjustedBitrateBps()]; |
| |
| OSStatus status = VTCompressionSessionEncodeFrame(_compressionSession, |
| pixelBuffer, |
| presentationTimeStamp, |
| kCMTimeInvalid, |
| frameProperties, |
| encodeParams.release(), |
| nullptr); |
| if (frameProperties) { |
| CFRelease(frameProperties); |
| } |
| if (pixelBuffer) { |
| CVBufferRelease(pixelBuffer); |
| } |
| if (status != noErr) { |
| LOG(LS_ERROR) << "Failed to encode frame with code: " << status; |
| return WEBRTC_VIDEO_CODEC_ERROR; |
| } |
| return WEBRTC_VIDEO_CODEC_OK; |
| } |
| |
| - (void)setCallback:(RTCVideoEncoderCallback)callback { |
| _callback = callback; |
| } |
| |
| - (int)setBitrate:(uint32_t)bitrateKbit framerate:(uint32_t)framerate { |
| _targetBitrateBps = 1000 * bitrateKbit; |
| _bitrateAdjuster->SetTargetBitrateBps(_targetBitrateBps); |
| [self setBitrateBps:_bitrateAdjuster->GetAdjustedBitrateBps()]; |
| return WEBRTC_VIDEO_CODEC_OK; |
| } |
| |
| #pragma mark - Private |
| |
| - (NSInteger)releaseEncoder { |
| // Need to destroy so that the session is invalidated and won't use the |
| // callback anymore. Do not remove callback until the session is invalidated |
| // since async encoder callbacks can occur until invalidation. |
| [self destroyCompressionSession]; |
| _callback = nullptr; |
| return WEBRTC_VIDEO_CODEC_OK; |
| } |
| |
| - (int)resetCompressionSession { |
| [self destroyCompressionSession]; |
| |
| // Set source image buffer attributes. These attributes will be present on |
| // buffers retrieved from the encoder's pixel buffer pool. |
| const size_t attributesSize = 3; |
| CFTypeRef keys[attributesSize] = { |
| #if defined(WEBRTC_IOS) |
| kCVPixelBufferOpenGLESCompatibilityKey, |
| #elif defined(WEBRTC_MAC) |
| kCVPixelBufferOpenGLCompatibilityKey, |
| #endif |
| kCVPixelBufferIOSurfacePropertiesKey, |
| kCVPixelBufferPixelFormatTypeKey |
| }; |
| CFDictionaryRef ioSurfaceValue = CreateCFTypeDictionary(nullptr, nullptr, 0); |
| int64_t nv12type = kCVPixelFormatType_420YpCbCr8BiPlanarFullRange; |
| CFNumberRef pixelFormat = CFNumberCreate(nullptr, kCFNumberLongType, &nv12type); |
| CFTypeRef values[attributesSize] = {kCFBooleanTrue, ioSurfaceValue, pixelFormat}; |
| CFDictionaryRef sourceAttributes = CreateCFTypeDictionary(keys, values, attributesSize); |
| if (ioSurfaceValue) { |
| CFRelease(ioSurfaceValue); |
| ioSurfaceValue = nullptr; |
| } |
| if (pixelFormat) { |
| CFRelease(pixelFormat); |
| pixelFormat = nullptr; |
| } |
| CFMutableDictionaryRef encoder_specs = nullptr; |
| #if defined(WEBRTC_MAC) && !defined(WEBRTC_IOS) |
| // Currently hw accl is supported above 360p on mac, below 360p |
| // the compression session will be created with hw accl disabled. |
| encoder_specs = CFDictionaryCreateMutable( |
| nullptr, 1, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks); |
| CFDictionarySetValue(encoder_specs, |
| kVTVideoEncoderSpecification_EnableHardwareAcceleratedVideoEncoder, |
| kCFBooleanTrue); |
| #endif |
| OSStatus status = |
| VTCompressionSessionCreate(nullptr, // use default allocator |
| _width, |
| _height, |
| kCMVideoCodecType_H264, |
| encoder_specs, // use hardware accelerated encoder if available |
| sourceAttributes, |
| nullptr, // use default compressed data allocator |
| compressionOutputCallback, |
| nullptr, |
| &_compressionSession); |
| if (sourceAttributes) { |
| CFRelease(sourceAttributes); |
| sourceAttributes = nullptr; |
| } |
| if (encoder_specs) { |
| CFRelease(encoder_specs); |
| encoder_specs = nullptr; |
| } |
| if (status != noErr) { |
| LOG(LS_ERROR) << "Failed to create compression session: " << status; |
| return WEBRTC_VIDEO_CODEC_ERROR; |
| } |
| #if defined(WEBRTC_MAC) && !defined(WEBRTC_IOS) |
| CFBooleanRef hwaccl_enabled = nullptr; |
| status = VTSessionCopyProperty(_compressionSession, |
| kVTCompressionPropertyKey_UsingHardwareAcceleratedVideoEncoder, |
| nullptr, |
| &hwaccl_enabled); |
| if (status == noErr && (CFBooleanGetValue(hwaccl_enabled))) { |
| LOG(LS_INFO) << "Compression session created with hw accl enabled"; |
| } else { |
| LOG(LS_INFO) << "Compression session created with hw accl disabled"; |
| } |
| #endif |
| [self configureCompressionSession]; |
| return WEBRTC_VIDEO_CODEC_OK; |
| } |
| |
| - (void)configureCompressionSession { |
| RTC_DCHECK(_compressionSession); |
| SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_RealTime, true); |
| SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_ProfileLevel, _profile); |
| SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_AllowFrameReordering, false); |
| [self setEncoderBitrateBps:_targetBitrateBps]; |
| // TODO(tkchin): Look at entropy mode and colorspace matrices. |
| // TODO(tkchin): Investigate to see if there's any way to make this work. |
| // May need it to interop with Android. Currently this call just fails. |
| // On inspecting encoder output on iOS8, this value is set to 6. |
| // internal::SetVTSessionProperty(compression_session_, |
| // kVTCompressionPropertyKey_MaxFrameDelayCount, |
| // 1); |
| |
| // Set a relatively large value for keyframe emission (7200 frames or 4 minutes). |
| SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_MaxKeyFrameInterval, 7200); |
| SetVTSessionProperty( |
| _compressionSession, kVTCompressionPropertyKey_MaxKeyFrameIntervalDuration, 240); |
| } |
| |
| - (void)destroyCompressionSession { |
| if (_compressionSession) { |
| VTCompressionSessionInvalidate(_compressionSession); |
| CFRelease(_compressionSession); |
| _compressionSession = nullptr; |
| } |
| } |
| |
| - (NSString *)implementationName { |
| return @"VideoToolbox"; |
| } |
| |
| - (void)setBitrateBps:(uint32_t)bitrateBps { |
| if (_encoderBitrateBps != bitrateBps) { |
| [self setEncoderBitrateBps:bitrateBps]; |
| } |
| } |
| |
| - (void)setEncoderBitrateBps:(uint32_t)bitrateBps { |
| if (_compressionSession) { |
| SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_AverageBitRate, bitrateBps); |
| |
| // TODO(tkchin): Add a helper method to set array value. |
| int64_t dataLimitBytesPerSecondValue = |
| static_cast<int64_t>(bitrateBps * kLimitToAverageBitRateFactor / 8); |
| CFNumberRef bytesPerSecond = |
| CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt64Type, &dataLimitBytesPerSecondValue); |
| int64_t oneSecondValue = 1; |
| CFNumberRef oneSecond = |
| CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt64Type, &oneSecondValue); |
| const void *nums[2] = {bytesPerSecond, oneSecond}; |
| CFArrayRef dataRateLimits = CFArrayCreate(nullptr, nums, 2, &kCFTypeArrayCallBacks); |
| OSStatus status = VTSessionSetProperty( |
| _compressionSession, kVTCompressionPropertyKey_DataRateLimits, dataRateLimits); |
| if (bytesPerSecond) { |
| CFRelease(bytesPerSecond); |
| } |
| if (oneSecond) { |
| CFRelease(oneSecond); |
| } |
| if (dataRateLimits) { |
| CFRelease(dataRateLimits); |
| } |
| if (status != noErr) { |
| LOG(LS_ERROR) << "Failed to set data rate limit"; |
| } |
| |
| _encoderBitrateBps = bitrateBps; |
| } |
| } |
| |
| - (void)frameWasEncoded:(OSStatus)status |
| flags:(VTEncodeInfoFlags)infoFlags |
| sampleBuffer:(CMSampleBufferRef)sampleBuffer |
| codecSpecificInfo:(id<RTCCodecSpecificInfo>)codecSpecificInfo |
| width:(int32_t)width |
| height:(int32_t)height |
| renderTimeMs:(int64_t)renderTimeMs |
| timestamp:(uint32_t)timestamp |
| rotation:(RTCVideoRotation)rotation { |
| if (status != noErr) { |
| LOG(LS_ERROR) << "H264 encode failed."; |
| return; |
| } |
| if (infoFlags & kVTEncodeInfo_FrameDropped) { |
| LOG(LS_INFO) << "H264 encode dropped frame."; |
| return; |
| } |
| |
| BOOL isKeyframe = NO; |
| CFArrayRef attachments = CMSampleBufferGetSampleAttachmentsArray(sampleBuffer, 0); |
| if (attachments != nullptr && CFArrayGetCount(attachments)) { |
| CFDictionaryRef attachment = |
| static_cast<CFDictionaryRef>(CFArrayGetValueAtIndex(attachments, 0)); |
| isKeyframe = !CFDictionaryContainsKey(attachment, kCMSampleAttachmentKey_NotSync); |
| } |
| |
| if (isKeyframe) { |
| LOG(LS_INFO) << "Generated keyframe"; |
| } |
| |
| // Convert the sample buffer into a buffer suitable for RTP packetization. |
| // TODO(tkchin): Allocate buffers through a pool. |
| std::unique_ptr<rtc::Buffer> buffer(new rtc::Buffer()); |
| RTCRtpFragmentationHeader *header; |
| { |
| std::unique_ptr<webrtc::RTPFragmentationHeader> header_cpp; |
| bool result = |
| H264CMSampleBufferToAnnexBBuffer(sampleBuffer, isKeyframe, buffer.get(), &header_cpp); |
| header = [[RTCRtpFragmentationHeader alloc] initWithNativeFragmentationHeader:header_cpp.get()]; |
| if (!result) { |
| return; |
| } |
| } |
| |
| RTCEncodedImage *frame = [[RTCEncodedImage alloc] init]; |
| frame.buffer = [NSData dataWithBytesNoCopy:buffer->data() length:buffer->size() freeWhenDone:NO]; |
| frame.encodedWidth = width; |
| frame.encodedHeight = height; |
| frame.completeFrame = YES; |
| frame.frameType = isKeyframe ? RTCFrameTypeVideoFrameKey : RTCFrameTypeVideoFrameDelta; |
| frame.captureTimeMs = renderTimeMs; |
| frame.timeStamp = timestamp; |
| frame.rotation = rotation; |
| frame.contentType = (_mode == RTCVideoCodecModeScreensharing) ? RTCVideoContentTypeScreenshare : |
| RTCVideoContentTypeUnspecified; |
| frame.flags = webrtc::TimingFrameFlags::kInvalid; |
| |
| int qp; |
| _h264BitstreamParser.ParseBitstream(buffer->data(), buffer->size()); |
| _h264BitstreamParser.GetLastSliceQp(&qp); |
| frame.qp = @(qp); |
| |
| BOOL res = _callback(frame, codecSpecificInfo, header); |
| if (!res) { |
| LOG(LS_ERROR) << "Encode callback failed"; |
| return; |
| } |
| _bitrateAdjuster->Update(frame.buffer.length); |
| } |
| |
| - (RTCVideoEncoderQpThresholds *)scalingSettings { |
| return [[RTCVideoEncoderQpThresholds alloc] initWithThresholdsLow:kLowH264QpThreshold |
| high:kHighH264QpThreshold]; |
| } |
| |
| @end |
