ZLMediaKit/src/Rtmp/RtmpDemuxer.cpp

/*
 * Copyright (c) 2016 The ZLMediaKit project authors. All Rights Reserved.
 *
 * This file is part of ZLMediaKit(https://github.com/xiongziliang/ZLMediaKit).
 *
 * Use of this source code is governed by MIT license that can be found in the
 * LICENSE file in the root of the source tree. All contributing project authors
 * may be found in the AUTHORS file in the root of the source tree.
 */

#include "RtmpDemuxer.h"
#include "Extension/Factory.h"

namespace mediakit {

bool RtmpDemuxer::loadMetaData(const AMFValue &val){
    bool ret = false;
    try {
        int audiosamplerate = 0;
        int audiochannels = 0;
        int audiosamplesize = 0;
        const AMFValue *audiocodecid = nullptr;
        const AMFValue *videocodecid = nullptr;
        val.object_for_each([&](const string &key, const AMFValue &val) {
            if (key == "duration") {
                _fDuration = val.as_number();
                return;
            }
            if (key == "audiosamplerate") {
                audiosamplerate = val.as_integer();
                return;
            }
            if (key == "audiosamplesize") {
                audiosamplesize = val.as_integer();
                return;
            }
            if (key == "stereo") {
                audiochannels = val.as_boolean() ? 2 : 1;
                return;
            }
            if (key == "videocodecid") {
                //找到视频
                videocodecid = &val;
                return;
            }
            if (key == "audiocodecid") {
                //找到音频
                audiocodecid = &val;
                return;
            }
        });
        if (videocodecid) {
            //有视频
            ret = true;
            makeVideoTrack(*videocodecid);
        }
        if (audiocodecid) {
            //有音频
            ret = true;
            makeAudioTrack(*audiocodecid, audiosamplerate, audiochannels, audiosamplesize);
        }
    } catch (std::exception &ex) {
        WarnL << ex.what();
    }
    return ret;
}

bool RtmpDemuxer::inputRtmp(const RtmpPacket::Ptr &pkt) {
    switch (pkt->typeId) {
        case MSG_VIDEO: {
            if(!_tryedGetVideoTrack){
                _tryedGetVideoTrack = true;
                auto codec = AMFValue(pkt->getMediaType());
                makeVideoTrack(codec);
            }
            if(_videoRtmpDecoder){
                return _videoRtmpDecoder->inputRtmp(pkt, true);
            }
            return false;
        }

        case MSG_AUDIO: {
            if(!_tryedGetAudioTrack) {
                _tryedGetAudioTrack = true;
                auto codec = AMFValue(pkt->getMediaType());
                makeAudioTrack(codec, pkt->getAudioSampleRate(), pkt->getAudioChannel(), pkt->getAudioSampleBit());
            }
            if(_audioRtmpDecoder){
                _audioRtmpDecoder->inputRtmp(pkt, false);
                return false;
            }
            return false;
        }
        default:
            return false;
    }
}

void RtmpDemuxer::makeVideoTrack(const AMFValue &videoCodec) {
    //生成Track对象
    _videoTrack = dynamic_pointer_cast<VideoTrack>(Factory::getVideoTrackByAmf(videoCodec));
    if (_videoTrack) {
        //生成rtmpCodec对象以便解码rtmp
        _videoRtmpDecoder = Factory::getRtmpCodecByTrack(_videoTrack, false);
        if (_videoRtmpDecoder) {
            //设置rtmp解码器代理，生成的frame写入该Track
            _videoRtmpDecoder->addDelegate(_videoTrack);
            onAddTrack(_videoTrack);
        } else {
            //找不到相应的rtmp解码器，该track无效
            _videoTrack.reset();
        }
    }
}

void RtmpDemuxer::makeAudioTrack(const AMFValue &audioCodec,int sample_rate, int channels, int sample_bit) {
    //生成Track对象
    _audioTrack = dynamic_pointer_cast<AudioTrack>(Factory::getAudioTrackByAmf(audioCodec, sample_rate, channels, sample_bit));
    if (_audioTrack) {
        //生成rtmpCodec对象以便解码rtmp
        _audioRtmpDecoder = Factory::getRtmpCodecByTrack(_audioTrack, false);
        if (_audioRtmpDecoder) {
            //设置rtmp解码器代理，生成的frame写入该Track
            _audioRtmpDecoder->addDelegate(_audioTrack);
            onAddTrack(_audioTrack);
        } else {
            //找不到相应的rtmp解码器，该track无效
            _audioTrack.reset();
        }
    }
}


} /* namespace mediakit */