FFmpeg RTSP转RTSP

    AVOutputFormat *ofmt = NULL;
    //Input AVFormatContext and Output AVFormatContext  
    AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;
    AVPacket pkt;
    const char *in_filename, *out_filename;
    int ret, i;
    int videoindex = -1;
    int frame_index = 0;

    in_filename = src;//"rtsp://192.168.222.222:554/1.sdp";

    out_filename = des;//"rtsp://192.168.1.47:554/1.sdp";

    //Input  
    if ((ret = avformat_open_input(&ifmt_ctx, in_filename, 0, 0)) < 0) {
        printf("Could not open input file. in_filename(%s)\n", in_filename);
        goto end;
    }
    if ((ret = avformat_find_stream_info(ifmt_ctx, 0)) < 0) {
        printf("Failed to retrieve input stream information");
        goto end;
    }

    for (i = 0; i<ifmt_ctx->nb_streams; i++)
        if (ifmt_ctx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
            videoindex = i;
            break;
        }

    av_dump_format(ifmt_ctx, 0, in_filename, 0);

    //Output  
    avformat_alloc_output_context2(&ofmt_ctx, NULL, "rtsp", out_filename); //RTMP  

    if (!ofmt_ctx) {
        printf("Could not create output context\n");
        ret = AVERROR_UNKNOWN;
        goto end;
    }
    ofmt = ofmt_ctx->oformat;
    for (i = 0; i < ifmt_ctx->nb_streams; i++) {
        //Create output AVStream according to input AVStream  
        AVStream *in_stream = ifmt_ctx->streams[i];
        AVStream *out_stream = avformat_new_stream(ofmt_ctx, in_stream->codec->codec);
        if (!out_stream) {
            printf("Failed allocating output stream\n");
            ret = AVERROR_UNKNOWN;
            goto end;
        }
        //Copy the settings of AVCodecContext  
        ret = avcodec_copy_context(out_stream->codec, in_stream->codec);
        if (ret < 0) {
            printf("Failed to copy context from input to output stream codec context\n");
            goto end;
        }
        out_stream->codec->codec_tag = 0;
        if (ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER)
            out_stream->codec->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
    }
    //Dump Format------------------  
    av_dump_format(ofmt_ctx, 0, out_filename, 1);
    //Open output URL  
    if (!(ofmt->flags & AVFMT_NOFILE)) {
        ret = avio_open(&ofmt_ctx->pb, out_filename, AVIO_FLAG_WRITE);
        if (ret < 0) {
            printf("Could not open output URL '%s'", out_filename);
            goto end;
        }
    }
    //Write file header  
    ret = avformat_write_header(ofmt_ctx, NULL);
    if (ret < 0) {
        printf("Error occurred when opening output URL\n");
        goto end;
    }

#if USE_H264BSF  
    AVBitStreamFilterContext* h264bsfc = av_bitstream_filter_init("h264_mp4toannexb");
#endif  

    while (1) {
        AVStream *in_stream, *out_stream;
        //Get an AVPacket  
        ret = av_read_frame(ifmt_ctx, &pkt);
        if (ret < 0)
            break;
        //printf("--1----=%8d------=%d-----------\n",pkt.pts, pkt.stream_index);
        in_stream = ifmt_ctx->streams[pkt.stream_index];
        out_stream = ofmt_ctx->streams[pkt.stream_index];
        /* copy packet */
        //Convert PTS/DTS  
        pkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX));
        pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX));


        pkt.duration = av_rescale_q(pkt.duration, in_stream->time_base, out_stream->time_base);
        pkt.pos = -1;
        //Print to Screen  
        if (pkt.stream_index == videoindex) {
            //printf("Receive %8d video frames from input URL\n", frame_index);
            frame_index++;

#if USE_H264BSF  
            av_bitstream_filter_filter(h264bsfc, in_stream->codec, NULL, &pkt.data, &pkt.size, pkt.data, pkt.size, 0);
#endif  
        }
        //ret = av_write_frame(ofmt_ctx, &pkt);
        ret = av_interleaved_write_frame(ofmt_ctx, &pkt);

        if (ret < 0 && frame_index > 3) {
            printf("Error muxing packet\n");
            break;
        }

        av_free_packet(&pkt);
    }

#if USE_H264BSF  
    av_bitstream_filter_close(h264bsfc);
#endif  
    //Write file trailer  
    av_write_trailer(ofmt_ctx);
end:
    avformat_close_input(&ifmt_ctx);
    /* close output */
    if (ofmt_ctx && !(ofmt->flags & AVFMT_NOFILE))
        avio_close(ofmt_ctx->pb);
    avformat_free_context(ofmt_ctx);
    printf("-----finish------\n");
    if (ret < 0 && ret != AVERROR_EOF) {
        printf("Error occurred.\n");
        return -1;
    }
    return 0;