//通过stap_a模式发送sps和pps包给对端。
int32_t yang_push_h264_package_stap_a(void *psession,YangPushH264Rtp *rtp, YangFrame *videoFrame) {int err = Yang_Ok;YangRtcSession *session=(YangRtcSession*)psession;//重置rtpPacket的字段yang_reset_rtpPacket(&rtp->videoStapPacket);//设置payloadType为h264rtp->videoStapPacket.header.payload_type = YangH264PayloadType;//设置ssrc为videoSsrcrtp->videoStapPacket.header.ssrc = rtp->videoSsrc;//设置帧类型为Videortp->videoStapPacket.frame_type = YangFrameTypeVideo;//设置naluType为StapA，此模式下一个nalu包可以通过多个rtp包发送，此时多个rtp包的时间戳相同。rtp->videoStapPacket.nalu_type = (YangAvcNaluType) kStapA;//设置marker为falsertp->videoStapPacket.header.marker = false;//设置sequence为videoSeqrtp->videoStapPacket.header.sequence = rtp->videoSeq++;//设置timestamp为视频帧的显示时间戳rtp->videoStapPacket.header.timestamp = videoFrame->pts;//设置视频的payload_type为StapA的模式rtp->videoStapPacket.payload_type = YangRtspPacketPayloadTypeSTAP;//重置stapA的datayang_reset_h2645_stap(&rtp->stapData);//创建sps和pps的结构体变量YangSample sps_sample;YangSample pps_sample;//从视频帧的payload中取出sps和ppsyang_decodeMetaH264(videoFrame->payload, videoFrame->nb, &sps_sample,&pps_sample);//从sps中取出NaluType赋值给stapData的nriuint8_t header = (uint8_t) sps_sample.bytes[0];rtp->stapData.nri = (YangAvcNaluType) header;//将sps和pps分别插入stapData.nalus中。yang_insert_YangSampleVector(&rtp->stapData.nalus, &sps_sample);yang_insert_YangSampleVector(&rtp->stapData.nalus, &pps_sample);//调用yang_push_h264_encodeVideo方法编码rtp的视频buffer，发送给p2p对端。if ((err = yang_push_h264_encodeVideo(session, rtp, &rtp->videoStapPacket))!= Yang_Ok) {return yang_error_wrap(err, "encode packet");}return err;
}