Cockpit-cpp/ZjServer/webrtcinterop/VideoDecoder.h

/* ---------------------------------------------------------------------------
** This software is in the public domain, furnished "as is", without technical
** support, and with no warranty, express or implied, as to its usefulness for
** any purpose.
**
** VideoDecoder.h
**
** -------------------------------------------------------------------------*/

#pragma once

#include <string.h>
#include <vector>

#include "api/video/i420_buffer.h"
#include "modules/video_coding/include/video_error_codes.h"
#include "modules/video_coding/h264_sprop_parameter_sets.h"


class VideoDecoder : public webrtc::DecodedImageCallback {
    private:
         class Frame
        {
            public:
                Frame(): m_timestamp_ms(0) {}
                Frame(const rtc::scoped_refptr<webrtc::EncodedImageBuffer> & content, uint64_t timestamp_ms, webrtc::VideoFrameType frameType) : m_content(content), m_timestamp_ms(timestamp_ms), m_frameType(frameType) {}
            
                rtc::scoped_refptr<webrtc::EncodedImageBuffer>   m_content;
                uint64_t               m_timestamp_ms;
                webrtc::VideoFrameType m_frameType;
        };

    public:
        VideoDecoder(rtc::VideoBroadcaster& broadcaster, std::unique_ptr<webrtc::VideoDecoderFactory>& videoDecoderFactory, bool wait) : 
                m_broadcaster(broadcaster),
                m_factory(videoDecoderFactory),
                m_stop(false),
                m_wait(wait),
              
                m_previmagets(0),
                m_prevts(0) {
        }

        virtual ~VideoDecoder() {
        }

        void DecoderThread() 
        {
            while (!m_stop) {
                std::unique_lock<std::mutex> mlock(m_queuemutex);
                while (m_queue.empty())
                {
                    m_queuecond.wait(mlock);
                }
                Frame frame = m_queue.front();
                m_queue.pop();		
                mlock.unlock();
                
                if (frame.m_content.get() != NULL) {
                    RTC_LOG(LS_VERBOSE) << "VideoDecoder::DecoderThread size:" << frame.m_content->size() << " ts:" << frame.m_timestamp_ms;
                    ssize_t size = frame.m_content->size();
                    
                    if (size) {
                        webrtc::EncodedImage input_image;
                        input_image.SetEncodedData(frame.m_content);		
                        input_image._frameType = frame.m_frameType;
                        input_image.ntp_time_ms_ = frame.m_timestamp_ms;
                        input_image.SetTimestamp(frame.m_timestamp_ms); // store time in ms that overflow the 32bits
                        int res = m_decoder->Decode(input_image, false, frame.m_timestamp_ms);
                        if (res != WEBRTC_VIDEO_CODEC_OK) {
                            RTC_LOG(LS_ERROR) << "VideoDecoder::DecoderThread failure:" << res;
                        }
                    }
                }
            }
        }


        void Start()
        {
            RTC_LOG(LS_INFO) << "VideoDecoder::start";
            m_stop = false;
            m_decoderthread = std::thread(&VideoDecoder::DecoderThread, this);
        }

        void Stop()
        {
            RTC_LOG(LS_INFO) << "VideoDecoder::stop";
            m_stop = true;
            Frame frame;			
            {
                std::unique_lock<std::mutex> lock(m_queuemutex);
                m_queue.push(frame);
            }
            m_queuecond.notify_all();
            m_decoderthread.join();
        }
 std::vector< std::vector<uint8_t> > getInitFrames(const std::string & codec, const char* sdp) {
            std::vector< std::vector<uint8_t> > frames;

            if (codec == "H264") {
                const char* pattern="sprop-parameter-sets=";
                const char* sprop=strstr(sdp, pattern);
                if (sprop)
                {
                    std::string sdpstr(sprop+strlen(pattern));
                    size_t pos = sdpstr.find_first_of(" ;\r\n");
                    if (pos != std::string::npos)
                    {
                        sdpstr.erase(pos);
                    }
                    webrtc::H264SpropParameterSets sprops;
                    if (sprops.DecodeSprop(sdpstr))
                    {
                        std::vector<uint8_t> sps;
                        sps.insert(sps.end(), H26X_marker, H26X_marker+sizeof(H26X_marker));
                        sps.insert(sps.end(), sprops.sps_nalu().begin(), sprops.sps_nalu().end());
                        frames.push_back(sps);

                        std::vector<uint8_t> pps;
                        pps.insert(pps.end(), H26X_marker, H26X_marker+sizeof(H26X_marker));
                        pps.insert(pps.end(), sprops.pps_nalu().begin(), sprops.pps_nalu().end());
                        frames.push_back(pps);
                    }
                    else
                    {
                        RTC_LOG(WARNING) << "Cannot decode SPS:" << sprop;
                    }
                }
            }

            return frames;
        }


        void createDecoder(const std::string & codec, int width = 0, int height = 0) {
            webrtc::VideoCodec codec_settings;
            codec_settings.width=width;
            codec_settings.height=height;
            if (codec == "H264") {
                m_decoder=m_factory->CreateVideoDecoder(webrtc::SdpVideoFormat(cricket::kH264CodecName));
                codec_settings.codecType = webrtc::VideoCodecType::kVideoCodecH264;
               
            }  
            if (m_decoder.get() != NULL) {
                m_decoder->InitDecode(&codec_settings,2);
                m_decoder->RegisterDecodeCompleteCallback(this);
            }
        }

        void destroyDecoder() {
            m_decoder.reset(NULL);
        }

        bool hasDecoder() {
            return (m_decoder.get() != NULL);
        }

        void PostFrame(const rtc::scoped_refptr<webrtc::EncodedImageBuffer>& content, uint64_t ts, webrtc::VideoFrameType frameType) {
			Frame frame(content, ts, frameType);			
			{
				std::unique_lock<std::mutex> lock(m_queuemutex);
				m_queue.push(frame);
			}
			m_queuecond.notify_all();
        }


		// overide webrtc::DecodedImageCallback
		virtual int32_t Decoded(webrtc::VideoFrame& decodedImage) override {
            int64_t ts = std::chrono::high_resolution_clock::now().time_since_epoch().count()/1000/1000;

            RTC_LOG(LS_VERBOSE) << "VideoDecoder::Decoded size:" << decodedImage.size() 
                        << " decode ts:" << decodedImage.ntp_time_ms()
                        << " source ts:" << ts;

            // waiting 
            if ( (m_wait) && (m_prevts != 0) ) {
                int64_t periodSource = decodedImage.timestamp() - m_previmagets;
                int64_t periodDecode = ts-m_prevts;
                    
                RTC_LOG(LS_VERBOSE) << "VideoDecoder::Decoded interframe decode:" << periodDecode << " source:" << periodSource;
                int64_t delayms = periodSource-periodDecode;
                if ( (delayms > 0) && (delayms < 1000) ) {
                    std::this_thread::sleep_for(std::chrono::milliseconds(delayms));			
                }
            } else {
                std::this_thread::sleep_for(std::chrono::milliseconds(5));
            }    
          

		     
          
            m_broadcaster.OnFrame(decodedImage);
            
	        m_previmagets = decodedImage.timestamp();
	        m_prevts = std::chrono::high_resolution_clock::now().time_since_epoch().count()/1000/1000;
                       
            return 1;
        }

        rtc::VideoBroadcaster&                        m_broadcaster;
        std::unique_ptr<webrtc::VideoDecoderFactory>& m_factory;
        std::unique_ptr<webrtc::VideoDecoder>         m_decoder;

		std::queue<Frame>                     m_queue;
		std::mutex                            m_queuemutex;
		std::condition_variable               m_queuecond;
		std::thread                           m_decoderthread;     
        bool                                  m_stop;   

        bool                                  m_wait;
        int64_t                               m_previmagets;	
        int64_t                               m_prevts;
      

};