| /* |
| * 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 "RTCVideoEncoderH264.h" |
| |
| #import <VideoToolbox/VideoToolbox.h> |
| #include <vector> |
| |
| #if defined(WEBRTC_IOS) |
| #import "helpers/UIDevice+RTCDevice.h" |
| #endif |
| #import "RTCCodecSpecificInfoH264.h" |
| #import "RTCH264ProfileLevelId.h" |
| #import "api/peerconnection/RTCVideoCodecInfo+Private.h" |
| #import "base/RTCCodecSpecificInfo.h" |
| #import "base/RTCI420Buffer.h" |
| #import "base/RTCVideoEncoder.h" |
| #import "base/RTCVideoFrame.h" |
| #import "base/RTCVideoFrameBuffer.h" |
| #import "components/video_frame_buffer/RTCCVPixelBuffer.h" |
| #import "helpers.h" |
| |
| #include "api/video_codecs/h264_profile_level_id.h" |
| #include "common_video/h264/h264_bitstream_parser.h" |
| #include "common_video/include/bitrate_adjuster.h" |
| #include "modules/video_coding/include/video_error_codes.h" |
| #include "rtc_base/buffer.h" |
| #include "rtc_base/logging.h" |
| #include "rtc_base/time_utils.h" |
| #include "sdk/objc/components/video_codec/nalu_rewriter.h" |
| #include "third_party/libyuv/include/libyuv/convert_from.h" |
| |
| @interface RTC_OBJC_TYPE (RTCVideoEncoderH264) |
| () |
| |
| - (void)frameWasEncoded : (OSStatus)status flags : (VTEncodeInfoFlags)infoFlags sampleBuffer |
| : (CMSampleBufferRef)sampleBuffer codecSpecificInfo |
| : (id<RTC_OBJC_TYPE(RTCCodecSpecificInfo)>)codecSpecificInfo width : (int32_t)width height |
| : (int32_t)height renderTimeMs : (int64_t)renderTimeMs timestamp : (uint32_t)timestamp rotation |
| : (RTCVideoRotation)rotation; |
| |
| @end |
| |
| namespace { // anonymous namespace |
| |
| // 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; |
| |
| const OSType kNV12PixelFormat = kCVPixelFormatType_420YpCbCr8BiPlanarFullRange; |
| |
| // Struct that we pass to the encoder per frame to encode. We receive it again |
| // in the encoder callback. |
| struct RTCFrameEncodeParams { |
| RTCFrameEncodeParams(RTC_OBJC_TYPE(RTCVideoEncoderH264) * e, |
| RTC_OBJC_TYPE(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 = [[RTC_OBJC_TYPE(RTCCodecSpecificInfoH264) alloc] init]; |
| } |
| } |
| |
| RTC_OBJC_TYPE(RTCVideoEncoderH264) * encoder; |
| RTC_OBJC_TYPE(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 CopyVideoFrameToNV12PixelBuffer(id<RTC_OBJC_TYPE(RTCI420Buffer)> frameBuffer, |
| CVPixelBufferRef pixelBuffer) { |
| RTC_DCHECK(pixelBuffer); |
| RTC_DCHECK_EQ(CVPixelBufferGetPixelFormatType(pixelBuffer), kNV12PixelFormat); |
| RTC_DCHECK_EQ(CVPixelBufferGetHeightOfPlane(pixelBuffer, 0), frameBuffer.height); |
| RTC_DCHECK_EQ(CVPixelBufferGetWidthOfPlane(pixelBuffer, 0), frameBuffer.width); |
| |
| CVReturn cvRet = CVPixelBufferLockBaseAddress(pixelBuffer, 0); |
| if (cvRet != kCVReturnSuccess) { |
| RTC_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) { |
| RTC_LOG(LS_ERROR) << "Error converting I420 VideoFrame to NV12 :" << ret; |
| return false; |
| } |
| return true; |
| } |
| |
| CVPixelBufferRef CreatePixelBuffer(VTCompressionSessionRef compression_session) { |
| if (!compression_session) { |
| RTC_LOG(LS_ERROR) << "Failed to get compression session."; |
| return nullptr; |
| } |
| CVPixelBufferPoolRef pixel_buffer_pool = |
| VTCompressionSessionGetPixelBufferPool(compression_session); |
| |
| if (!pixel_buffer_pool) { |
| RTC_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) { |
| RTC_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) { |
| if (!params) { |
| // If there are pending callbacks when the encoder is destroyed, this can happen. |
| return; |
| } |
| 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 webrtc::SdpVideoFormat. 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 webrtc::H264ProfileLevelId &profile_level_id) { |
| switch (profile_level_id.profile) { |
| case webrtc::H264Profile::kProfileConstrainedBaseline: |
| case webrtc::H264Profile::kProfileBaseline: |
| switch (profile_level_id.level) { |
| case webrtc::H264Level::kLevel3: |
| return kVTProfileLevel_H264_Baseline_3_0; |
| case webrtc::H264Level::kLevel3_1: |
| return kVTProfileLevel_H264_Baseline_3_1; |
| case webrtc::H264Level::kLevel3_2: |
| return kVTProfileLevel_H264_Baseline_3_2; |
| case webrtc::H264Level::kLevel4: |
| return kVTProfileLevel_H264_Baseline_4_0; |
| case webrtc::H264Level::kLevel4_1: |
| return kVTProfileLevel_H264_Baseline_4_1; |
| case webrtc::H264Level::kLevel4_2: |
| return kVTProfileLevel_H264_Baseline_4_2; |
| case webrtc::H264Level::kLevel5: |
| return kVTProfileLevel_H264_Baseline_5_0; |
| case webrtc::H264Level::kLevel5_1: |
| return kVTProfileLevel_H264_Baseline_5_1; |
| case webrtc::H264Level::kLevel5_2: |
| return kVTProfileLevel_H264_Baseline_5_2; |
| case webrtc::H264Level::kLevel1: |
| case webrtc::H264Level::kLevel1_b: |
| case webrtc::H264Level::kLevel1_1: |
| case webrtc::H264Level::kLevel1_2: |
| case webrtc::H264Level::kLevel1_3: |
| case webrtc::H264Level::kLevel2: |
| case webrtc::H264Level::kLevel2_1: |
| case webrtc::H264Level::kLevel2_2: |
| return kVTProfileLevel_H264_Baseline_AutoLevel; |
| } |
| |
| case webrtc::H264Profile::kProfileMain: |
| switch (profile_level_id.level) { |
| case webrtc::H264Level::kLevel3: |
| return kVTProfileLevel_H264_Main_3_0; |
| case webrtc::H264Level::kLevel3_1: |
| return kVTProfileLevel_H264_Main_3_1; |
| case webrtc::H264Level::kLevel3_2: |
| return kVTProfileLevel_H264_Main_3_2; |
| case webrtc::H264Level::kLevel4: |
| return kVTProfileLevel_H264_Main_4_0; |
| case webrtc::H264Level::kLevel4_1: |
| return kVTProfileLevel_H264_Main_4_1; |
| case webrtc::H264Level::kLevel4_2: |
| return kVTProfileLevel_H264_Main_4_2; |
| case webrtc::H264Level::kLevel5: |
| return kVTProfileLevel_H264_Main_5_0; |
| case webrtc::H264Level::kLevel5_1: |
| return kVTProfileLevel_H264_Main_5_1; |
| case webrtc::H264Level::kLevel5_2: |
| return kVTProfileLevel_H264_Main_5_2; |
| case webrtc::H264Level::kLevel1: |
| case webrtc::H264Level::kLevel1_b: |
| case webrtc::H264Level::kLevel1_1: |
| case webrtc::H264Level::kLevel1_2: |
| case webrtc::H264Level::kLevel1_3: |
| case webrtc::H264Level::kLevel2: |
| case webrtc::H264Level::kLevel2_1: |
| case webrtc::H264Level::kLevel2_2: |
| return kVTProfileLevel_H264_Main_AutoLevel; |
| } |
| |
| case webrtc::H264Profile::kProfileConstrainedHigh: |
| case webrtc::H264Profile::kProfileHigh: |
| case webrtc::H264Profile::kProfilePredictiveHigh444: |
| switch (profile_level_id.level) { |
| case webrtc::H264Level::kLevel3: |
| return kVTProfileLevel_H264_High_3_0; |
| case webrtc::H264Level::kLevel3_1: |
| return kVTProfileLevel_H264_High_3_1; |
| case webrtc::H264Level::kLevel3_2: |
| return kVTProfileLevel_H264_High_3_2; |
| case webrtc::H264Level::kLevel4: |
| return kVTProfileLevel_H264_High_4_0; |
| case webrtc::H264Level::kLevel4_1: |
| return kVTProfileLevel_H264_High_4_1; |
| case webrtc::H264Level::kLevel4_2: |
| return kVTProfileLevel_H264_High_4_2; |
| case webrtc::H264Level::kLevel5: |
| return kVTProfileLevel_H264_High_5_0; |
| case webrtc::H264Level::kLevel5_1: |
| return kVTProfileLevel_H264_High_5_1; |
| case webrtc::H264Level::kLevel5_2: |
| return kVTProfileLevel_H264_High_5_2; |
| case webrtc::H264Level::kLevel1: |
| case webrtc::H264Level::kLevel1_b: |
| case webrtc::H264Level::kLevel1_1: |
| case webrtc::H264Level::kLevel1_2: |
| case webrtc::H264Level::kLevel1_3: |
| case webrtc::H264Level::kLevel2: |
| case webrtc::H264Level::kLevel2_1: |
| case webrtc::H264Level::kLevel2_2: |
| return kVTProfileLevel_H264_High_AutoLevel; |
| } |
| } |
| } |
| |
| // The function returns the max allowed sample rate (pixels per second) that |
| // can be processed by given encoder with `profile_level_id`. |
| // See https://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-H.264-201610-S!!PDF-E&type=items |
| // for details. |
| NSUInteger GetMaxSampleRate(const webrtc::H264ProfileLevelId &profile_level_id) { |
| switch (profile_level_id.level) { |
| case webrtc::H264Level::kLevel3: |
| return 10368000; |
| case webrtc::H264Level::kLevel3_1: |
| return 27648000; |
| case webrtc::H264Level::kLevel3_2: |
| return 55296000; |
| case webrtc::H264Level::kLevel4: |
| case webrtc::H264Level::kLevel4_1: |
| return 62914560; |
| case webrtc::H264Level::kLevel4_2: |
| return 133693440; |
| case webrtc::H264Level::kLevel5: |
| return 150994944; |
| case webrtc::H264Level::kLevel5_1: |
| return 251658240; |
| case webrtc::H264Level::kLevel5_2: |
| return 530841600; |
| case webrtc::H264Level::kLevel1: |
| case webrtc::H264Level::kLevel1_b: |
| case webrtc::H264Level::kLevel1_1: |
| case webrtc::H264Level::kLevel1_2: |
| case webrtc::H264Level::kLevel1_3: |
| case webrtc::H264Level::kLevel2: |
| case webrtc::H264Level::kLevel2_1: |
| case webrtc::H264Level::kLevel2_2: |
| // Zero means auto rate setting. |
| return 0; |
| } |
| } |
| } // namespace |
| |
| @implementation RTC_OBJC_TYPE (RTCVideoEncoderH264) { |
| RTC_OBJC_TYPE(RTCVideoCodecInfo) * _codecInfo; |
| std::unique_ptr<webrtc::BitrateAdjuster> _bitrateAdjuster; |
| uint32_t _targetBitrateBps; |
| uint32_t _encoderBitrateBps; |
| uint32_t _encoderFrameRate; |
| uint32_t _maxAllowedFrameRate; |
| RTCH264PacketizationMode _packetizationMode; |
| absl::optional<webrtc::H264ProfileLevelId> _profile_level_id; |
| RTCVideoEncoderCallback _callback; |
| int32_t _width; |
| int32_t _height; |
| VTCompressionSessionRef _compressionSession; |
| RTCVideoCodecMode _mode; |
| |
| webrtc::H264BitstreamParser _h264BitstreamParser; |
| std::vector<uint8_t> _frameScaleBuffer; |
| } |
| |
| // .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:(RTC_OBJC_TYPE(RTCVideoCodecInfo) *)codecInfo { |
| if (self = [super init]) { |
| _codecInfo = codecInfo; |
| _bitrateAdjuster.reset(new webrtc::BitrateAdjuster(.5, .95)); |
| _packetizationMode = RTCH264PacketizationModeNonInterleaved; |
| _profile_level_id = |
| webrtc::ParseSdpForH264ProfileLevelId([codecInfo nativeSdpVideoFormat].parameters); |
| RTC_DCHECK(_profile_level_id); |
| RTC_LOG(LS_INFO) << "Using profile " << CFStringToString(ExtractProfile(*_profile_level_id)); |
| RTC_CHECK([codecInfo.name isEqualToString:kRTCVideoCodecH264Name]); |
| } |
| return self; |
| } |
| |
| - (void)dealloc { |
| [self destroyCompressionSession]; |
| } |
| |
| - (NSInteger)startEncodeWithSettings:(RTC_OBJC_TYPE(RTCVideoEncoderSettings) *)settings |
| numberOfCores:(int)numberOfCores { |
| RTC_DCHECK(settings); |
| RTC_DCHECK([settings.name isEqualToString:kRTCVideoCodecH264Name]); |
| |
| _width = settings.width; |
| _height = settings.height; |
| _mode = settings.mode; |
| |
| uint32_t aligned_width = (((_width + 15) >> 4) << 4); |
| uint32_t aligned_height = (((_height + 15) >> 4) << 4); |
| _maxAllowedFrameRate = static_cast<uint32_t>(GetMaxSampleRate(*_profile_level_id) / |
| (aligned_width * aligned_height)); |
| |
| // We can only set average bitrate on the HW encoder. |
| _targetBitrateBps = settings.startBitrate * 1000; // startBitrate is in kbps. |
| _bitrateAdjuster->SetTargetBitrateBps(_targetBitrateBps); |
| _encoderFrameRate = MIN(settings.maxFramerate, _maxAllowedFrameRate); |
| if (settings.maxFramerate > _maxAllowedFrameRate && _maxAllowedFrameRate > 0) { |
| RTC_LOG(LS_WARNING) << "Initial encoder frame rate setting " << settings.maxFramerate |
| << " is larger than the " |
| << "maximal allowed frame rate " << _maxAllowedFrameRate << "."; |
| } |
| |
| // TODO(tkchin): Try setting payload size via |
| // kVTCompressionPropertyKey_MaxH264SliceBytes. |
| |
| return [self resetCompressionSessionWithPixelFormat:kNV12PixelFormat]; |
| } |
| |
| - (NSInteger)encode:(RTC_OBJC_TYPE(RTCVideoFrame) *)frame |
| codecSpecificInfo:(nullable id<RTC_OBJC_TYPE(RTCCodecSpecificInfo)>)codecSpecificInfo |
| frameTypes:(NSArray<NSNumber *> *)frameTypes { |
| if (!_callback || !_compressionSession) { |
| return WEBRTC_VIDEO_CODEC_UNINITIALIZED; |
| } |
| BOOL isKeyframeRequired = NO; |
| |
| // Get a pixel buffer from the pool and copy frame data over. |
| if ([self resetCompressionSessionIfNeededWithFrame:frame]) { |
| isKeyframeRequired = YES; |
| } |
| |
| CVPixelBufferRef pixelBuffer = nullptr; |
| if ([frame.buffer isKindOfClass:[RTC_OBJC_TYPE(RTCCVPixelBuffer) class]]) { |
| // Native frame buffer |
| RTC_OBJC_TYPE(RTCCVPixelBuffer) *rtcPixelBuffer = |
| (RTC_OBJC_TYPE(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(_compressionSession); |
| 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]; |
| _frameScaleBuffer.resize(size); |
| } else { |
| _frameScaleBuffer.clear(); |
| } |
| _frameScaleBuffer.shrink_to_fit(); |
| if (![rtcPixelBuffer cropAndScaleTo:pixelBuffer withTempBuffer:_frameScaleBuffer.data()]) { |
| CVBufferRelease(pixelBuffer); |
| return WEBRTC_VIDEO_CODEC_ERROR; |
| } |
| } |
| } |
| |
| if (!pixelBuffer) { |
| // We did not have a native frame buffer |
| RTC_DCHECK_EQ(frame.width, _width); |
| RTC_DCHECK_EQ(frame.height, _height); |
| |
| pixelBuffer = CreatePixelBuffer(_compressionSession); |
| if (!pixelBuffer) { |
| return WEBRTC_VIDEO_CODEC_ERROR; |
| } |
| RTC_DCHECK(pixelBuffer); |
| if (!CopyVideoFrameToNV12PixelBuffer([frame.buffer toI420], pixelBuffer)) { |
| RTC_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() frameRate:_encoderFrameRate]; |
| |
| OSStatus status = VTCompressionSessionEncodeFrame(_compressionSession, |
| pixelBuffer, |
| presentationTimeStamp, |
| kCMTimeInvalid, |
| frameProperties, |
| encodeParams.release(), |
| nullptr); |
| if (frameProperties) { |
| CFRelease(frameProperties); |
| } |
| if (pixelBuffer) { |
| CVBufferRelease(pixelBuffer); |
| } |
| |
| if (status == kVTInvalidSessionErr) { |
| // This error occurs when entering foreground after backgrounding the app. |
| RTC_LOG(LS_ERROR) << "Invalid compression session, resetting."; |
| [self resetCompressionSessionWithPixelFormat:[self pixelFormatOfFrame:frame]]; |
| |
| return WEBRTC_VIDEO_CODEC_NO_OUTPUT; |
| } else if (status == kVTVideoEncoderMalfunctionErr) { |
| // Sometimes the encoder malfunctions and needs to be restarted. |
| RTC_LOG(LS_ERROR) |
| << "Encountered video encoder malfunction error. Resetting compression session."; |
| [self resetCompressionSessionWithPixelFormat:[self pixelFormatOfFrame:frame]]; |
| |
| return WEBRTC_VIDEO_CODEC_NO_OUTPUT; |
| } else if (status != noErr) { |
| RTC_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); |
| if (framerate > _maxAllowedFrameRate && _maxAllowedFrameRate > 0) { |
| RTC_LOG(LS_WARNING) << "Encoder frame rate setting " << framerate << " is larger than the " |
| << "maximal allowed frame rate " << _maxAllowedFrameRate << "."; |
| } |
| framerate = MIN(framerate, _maxAllowedFrameRate); |
| [self setBitrateBps:_bitrateAdjuster->GetAdjustedBitrateBps() frameRate:framerate]; |
| return WEBRTC_VIDEO_CODEC_OK; |
| } |
| |
| - (NSInteger)resolutionAlignment { |
| return 1; |
| } |
| |
| - (BOOL)applyAlignmentToAllSimulcastLayers { |
| return NO; |
| } |
| |
| - (BOOL)supportsNativeHandle { |
| return YES; |
| } |
| |
| #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; |
| } |
| |
| - (OSType)pixelFormatOfFrame:(RTC_OBJC_TYPE(RTCVideoFrame) *)frame { |
| // Use NV12 for non-native frames. |
| if ([frame.buffer isKindOfClass:[RTC_OBJC_TYPE(RTCCVPixelBuffer) class]]) { |
| RTC_OBJC_TYPE(RTCCVPixelBuffer) *rtcPixelBuffer = |
| (RTC_OBJC_TYPE(RTCCVPixelBuffer) *)frame.buffer; |
| return CVPixelBufferGetPixelFormatType(rtcPixelBuffer.pixelBuffer); |
| } |
| |
| return kNV12PixelFormat; |
| } |
| |
| - (BOOL)resetCompressionSessionIfNeededWithFrame:(RTC_OBJC_TYPE(RTCVideoFrame) *)frame { |
| BOOL resetCompressionSession = NO; |
| |
| // If we're capturing native frames in another pixel format than the compression session is |
| // configured with, make sure the compression session is reset using the correct pixel format. |
| OSType framePixelFormat = [self pixelFormatOfFrame:frame]; |
| |
| if (_compressionSession) { |
| // The pool attribute `kCVPixelBufferPixelFormatTypeKey` can contain either an array of pixel |
| // formats or a single pixel format. |
| |
| CVPixelBufferPoolRef pixelBufferPool = |
| VTCompressionSessionGetPixelBufferPool(_compressionSession); |
| if (!pixelBufferPool) { |
| return NO; |
| } |
| |
| NSDictionary *poolAttributes = |
| (__bridge NSDictionary *)CVPixelBufferPoolGetPixelBufferAttributes(pixelBufferPool); |
| id pixelFormats = |
| [poolAttributes objectForKey:(__bridge NSString *)kCVPixelBufferPixelFormatTypeKey]; |
| NSArray<NSNumber *> *compressionSessionPixelFormats = nil; |
| if ([pixelFormats isKindOfClass:[NSArray class]]) { |
| compressionSessionPixelFormats = (NSArray *)pixelFormats; |
| } else if ([pixelFormats isKindOfClass:[NSNumber class]]) { |
| compressionSessionPixelFormats = @[ (NSNumber *)pixelFormats ]; |
| } |
| |
| if (![compressionSessionPixelFormats |
| containsObject:[NSNumber numberWithLong:framePixelFormat]]) { |
| resetCompressionSession = YES; |
| RTC_LOG(LS_INFO) << "Resetting compression session due to non-matching pixel format."; |
| } |
| } else { |
| resetCompressionSession = YES; |
| } |
| |
| if (resetCompressionSession) { |
| [self resetCompressionSessionWithPixelFormat:framePixelFormat]; |
| } |
| return resetCompressionSession; |
| } |
| |
| - (int)resetCompressionSessionWithPixelFormat:(OSType)framePixelFormat { |
| [self destroyCompressionSession]; |
| |
| // Set source image buffer attributes. These attributes will be present on |
| // buffers retrieved from the encoder's pixel buffer pool. |
| NSDictionary *sourceAttributes = @{ |
| #if defined(WEBRTC_IOS) && (TARGET_OS_MACCATALYST || TARGET_OS_SIMULATOR) |
| (NSString *)kCVPixelBufferMetalCompatibilityKey : @(YES), |
| #elif defined(WEBRTC_IOS) |
| (NSString *)kCVPixelBufferOpenGLESCompatibilityKey : @(YES), |
| #elif defined(WEBRTC_MAC) && !defined(WEBRTC_ARCH_ARM64) |
| (NSString *)kCVPixelBufferOpenGLCompatibilityKey : @(YES), |
| #endif |
| (NSString *)kCVPixelBufferIOSurfacePropertiesKey : @{}, |
| (NSString *)kCVPixelBufferPixelFormatTypeKey : @(framePixelFormat), |
| }; |
| |
| NSDictionary *encoder_specs; |
| #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 = @{ |
| (NSString *)kVTVideoEncoderSpecification_EnableHardwareAcceleratedVideoEncoder : @(YES), |
| }; |
| |
| #endif |
| OSStatus status = VTCompressionSessionCreate( |
| nullptr, // use default allocator |
| _width, |
| _height, |
| kCMVideoCodecType_H264, |
| (__bridge CFDictionaryRef)encoder_specs, // use hardware accelerated encoder if available |
| (__bridge CFDictionaryRef)sourceAttributes, |
| nullptr, // use default compressed data allocator |
| compressionOutputCallback, |
| nullptr, |
| &_compressionSession); |
| if (status != noErr) { |
| RTC_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))) { |
| RTC_LOG(LS_INFO) << "Compression session created with hw accl enabled"; |
| } else { |
| RTC_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, |
| ExtractProfile(*_profile_level_id)); |
| SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_AllowFrameReordering, false); |
| [self setEncoderBitrateBps:_targetBitrateBps frameRate:_encoderFrameRate]; |
| // 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 frameRate:(uint32_t)frameRate { |
| if (_encoderBitrateBps != bitrateBps || _encoderFrameRate != frameRate) { |
| [self setEncoderBitrateBps:bitrateBps frameRate:frameRate]; |
| } |
| } |
| |
| - (void)setEncoderBitrateBps:(uint32_t)bitrateBps frameRate:(uint32_t)frameRate { |
| if (_compressionSession) { |
| SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_AverageBitRate, bitrateBps); |
| |
| // With zero `_maxAllowedFrameRate`, we fall back to automatic frame rate detection. |
| if (_maxAllowedFrameRate > 0) { |
| SetVTSessionProperty( |
| _compressionSession, kVTCompressionPropertyKey_ExpectedFrameRate, frameRate); |
| } |
| |
| // 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) { |
| RTC_LOG(LS_ERROR) << "Failed to set data rate limit with code: " << status; |
| } |
| |
| _encoderBitrateBps = bitrateBps; |
| _encoderFrameRate = frameRate; |
| } |
| } |
| |
| - (void)frameWasEncoded:(OSStatus)status |
| flags:(VTEncodeInfoFlags)infoFlags |
| sampleBuffer:(CMSampleBufferRef)sampleBuffer |
| codecSpecificInfo:(id<RTC_OBJC_TYPE(RTCCodecSpecificInfo)>)codecSpecificInfo |
| width:(int32_t)width |
| height:(int32_t)height |
| renderTimeMs:(int64_t)renderTimeMs |
| timestamp:(uint32_t)timestamp |
| rotation:(RTCVideoRotation)rotation { |
| RTCVideoEncoderCallback callback = _callback; |
| if (!callback) { |
| return; |
| } |
| if (status != noErr) { |
| RTC_LOG(LS_ERROR) << "H264 encode failed with code: " << status; |
| return; |
| } |
| if (infoFlags & kVTEncodeInfo_FrameDropped) { |
| RTC_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) { |
| RTC_LOG(LS_INFO) << "Generated keyframe"; |
| } |
| |
| __block std::unique_ptr<rtc::Buffer> buffer = std::make_unique<rtc::Buffer>(); |
| if (!webrtc::H264CMSampleBufferToAnnexBBuffer(sampleBuffer, isKeyframe, buffer.get())) { |
| return; |
| } |
| |
| RTC_OBJC_TYPE(RTCEncodedImage) *frame = [[RTC_OBJC_TYPE(RTCEncodedImage) alloc] init]; |
| // This assumes ownership of `buffer` and is responsible for freeing it when done. |
| frame.buffer = [[NSData alloc] initWithBytesNoCopy:buffer->data() |
| length:buffer->size() |
| deallocator:^(void *bytes, NSUInteger size) { |
| buffer.reset(); |
| }]; |
| frame.encodedWidth = width; |
| frame.encodedHeight = height; |
| frame.frameType = isKeyframe ? RTCFrameTypeVideoFrameKey : RTCFrameTypeVideoFrameDelta; |
| frame.captureTimeMs = renderTimeMs; |
| frame.timeStamp = timestamp; |
| frame.rotation = rotation; |
| frame.contentType = (_mode == RTCVideoCodecModeScreensharing) ? RTCVideoContentTypeScreenshare : |
| RTCVideoContentTypeUnspecified; |
| frame.flags = webrtc::VideoSendTiming::kInvalid; |
| |
| _h264BitstreamParser.ParseBitstream(*buffer); |
| frame.qp = @(_h264BitstreamParser.GetLastSliceQp().value_or(-1)); |
| |
| BOOL res = callback(frame, codecSpecificInfo); |
| if (!res) { |
| RTC_LOG(LS_ERROR) << "Encode callback failed"; |
| return; |
| } |
| _bitrateAdjuster->Update(frame.buffer.length); |
| } |
| |
| - (nullable RTC_OBJC_TYPE(RTCVideoEncoderQpThresholds) *)scalingSettings { |
| return [[RTC_OBJC_TYPE(RTCVideoEncoderQpThresholds) alloc] |
| initWithThresholdsLow:kLowH264QpThreshold |
| high:kHighH264QpThreshold]; |
| } |
| |
| @end |
