ffmpeg.c

                     av_codec_get_tag(oc->oformat->codec_tag, icodec->codec_id) <= 0)
                    codec->codec_tag = icodec->codec_tag;
            }

            codec->bit_rate       = icodec->bit_rate;
            codec->rc_max_rate    = icodec->rc_max_rate;
            codec->rc_buffer_size = icodec->rc_buffer_size;
            codec->field_order    = icodec->field_order;
            codec->extradata      = av_mallocz(extra_size);
            if (!codec->extradata) {
                return AVERROR(ENOMEM);
            }
            memcpy(codec->extradata, icodec->extradata, icodec->extradata_size);
            codec->extradata_size= icodec->extradata_size;
            codec->bits_per_coded_sample  = icodec->bits_per_coded_sample;

            codec->time_base = ist->st->time_base;
            /*
             * Avi is a special case here because it supports variable fps but
             * having the fps and timebase differe significantly adds quite some
             * overhead
             */
            if(!strcmp(oc->oformat->name, "avi")) {
                if ( copy_tb<0 && av_q2d(ist->st->r_frame_rate) >= av_q2d(ist->st->avg_frame_rate)
                               && 0.5/av_q2d(ist->st->r_frame_rate) > av_q2d(ist->st->time_base)
                               && 0.5/av_q2d(ist->st->r_frame_rate) > av_q2d(icodec->time_base)
                               && av_q2d(ist->st->time_base) < 1.0/500 && av_q2d(icodec->time_base) < 1.0/500
                     || copy_tb==2){
                    codec->time_base.num = ist->st->r_frame_rate.den;
                    codec->time_base.den = 2*ist->st->r_frame_rate.num;
                    codec->ticks_per_frame = 2;
                } else if (   copy_tb<0 && av_q2d(icodec->time_base)*icodec->ticks_per_frame > 2*av_q2d(ist->st->time_base)
                                 && av_q2d(ist->st->time_base) < 1.0/500
                    || copy_tb==0){
                    codec->time_base = icodec->time_base;
                    codec->time_base.num *= icodec->ticks_per_frame;
                    codec->time_base.den *= 2;
                    codec->ticks_per_frame = 2;
                }
            } else if(!(oc->oformat->flags & AVFMT_VARIABLE_FPS)
                      && strcmp(oc->oformat->name, "mov") && strcmp(oc->oformat->name, "mp4") && strcmp(oc->oformat->name, "3gp")
                      && strcmp(oc->oformat->name, "3g2") && strcmp(oc->oformat->name, "psp") && strcmp(oc->oformat->name, "ipod")
            ) {
                if(   copy_tb<0 && av_q2d(icodec->time_base)*icodec->ticks_per_frame > av_q2d(ist->st->time_base)
                                && av_q2d(ist->st->time_base) < 1.0/500
                   || copy_tb==0){
                    codec->time_base = icodec->time_base;
                    codec->time_base.num *= icodec->ticks_per_frame;
                }
            }

            if(ost->frame_rate.num)
                codec->time_base = av_inv_q(ost->frame_rate);

            av_reduce(&codec->time_base.num, &codec->time_base.den,
                        codec->time_base.num, codec->time_base.den, INT_MAX);

            switch (codec->codec_type) {
            case AVMEDIA_TYPE_AUDIO:
                if (audio_volume != 256) {
                    av_log(NULL, AV_LOG_FATAL, "-acodec copy and -vol are incompatible (frames are not decoded)\n");
                    exit_program(1);
                }
                codec->channel_layout     = icodec->channel_layout;
                codec->sample_rate        = icodec->sample_rate;
                codec->channels           = icodec->channels;
                codec->frame_size         = icodec->frame_size;
                codec->audio_service_type = icodec->audio_service_type;
                codec->block_align        = icodec->block_align;
                if((codec->block_align == 1 || codec->block_align == 1152) && codec->codec_id == AV_CODEC_ID_MP3)
                    codec->block_align= 0;
                if(codec->codec_id == AV_CODEC_ID_AC3)
                    codec->block_align= 0;
                break;
            case AVMEDIA_TYPE_VIDEO:
                codec->pix_fmt            = icodec->pix_fmt;
                codec->width              = icodec->width;
                codec->height             = icodec->height;
                codec->has_b_frames       = icodec->has_b_frames;
                if (!codec->sample_aspect_ratio.num) {
                    codec->sample_aspect_ratio   =
                    ost->st->sample_aspect_ratio =
                        ist->st->sample_aspect_ratio.num ? ist->st->sample_aspect_ratio :
                        ist->st->codec->sample_aspect_ratio.num ?
                        ist->st->codec->sample_aspect_ratio : (AVRational){0, 1};
                }
                ost->st->avg_frame_rate = ist->st->avg_frame_rate;
                break;
            case AVMEDIA_TYPE_SUBTITLE:
                codec->width  = icodec->width;
                codec->height = icodec->height;
                break;
            case AVMEDIA_TYPE_DATA:
            case AVMEDIA_TYPE_ATTACHMENT:
                break;
            default:
                abort();
            }
        } else {
            if (!ost->enc)
                ost->enc = avcodec_find_encoder(codec->codec_id);
            if (!ost->enc) {
                /* should only happen when a default codec is not present. */
                snprintf(error, sizeof(error), "Encoder (codec %s) not found for output stream #%d:%d",
                         avcodec_get_name(ost->st->codec->codec_id), ost->file_index, ost->index);
                ret = AVERROR(EINVAL);
                goto dump_format;
            }

            if (ist)
                ist->decoding_needed++;
            ost->encoding_needed = 1;

            if (!ost->filter &&
                (codec->codec_type == AVMEDIA_TYPE_VIDEO ||
                 codec->codec_type == AVMEDIA_TYPE_AUDIO)) {
                    FilterGraph *fg;
                    fg = init_simple_filtergraph(ist, ost);
                    if (configure_filtergraph(fg)) {
                        av_log(NULL, AV_LOG_FATAL, "Error opening filters!\n");
                        exit(1);
                    }
            }

            if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
                if (ost->filter && !ost->frame_rate.num)
                    ost->frame_rate = av_buffersink_get_frame_rate(ost->filter->filter);
                if (ist && !ost->frame_rate.num)
                    ost->frame_rate = ist->st->r_frame_rate.num ? ist->st->r_frame_rate : (AVRational){25, 1};
//                    ost->frame_rate = ist->st->avg_frame_rate.num ? ist->st->avg_frame_rate : (AVRational){25, 1};
                if (ost->enc && ost->enc->supported_framerates && !ost->force_fps) {
                    int idx = av_find_nearest_q_idx(ost->frame_rate, ost->enc->supported_framerates);
                    ost->frame_rate = ost->enc->supported_framerates[idx];
                }
            }

            switch (codec->codec_type) {
            case AVMEDIA_TYPE_AUDIO:
                codec->sample_fmt     = ost->filter->filter->inputs[0]->format;
                codec->sample_rate    = ost->filter->filter->inputs[0]->sample_rate;
                codec->channel_layout = ost->filter->filter->inputs[0]->channel_layout;
                codec->channels       = av_get_channel_layout_nb_channels(codec->channel_layout);
                codec->time_base      = (AVRational){ 1, codec->sample_rate };
                break;
            case AVMEDIA_TYPE_VIDEO:
                codec->time_base = av_inv_q(ost->frame_rate);
                if (ost->filter && !(codec->time_base.num && codec->time_base.den))
                    codec->time_base = ost->filter->filter->inputs[0]->time_base;
                if (   av_q2d(codec->time_base) < 0.001 && video_sync_method != VSYNC_PASSTHROUGH
                   && (video_sync_method == VSYNC_CFR || (video_sync_method == VSYNC_AUTO && !(oc->oformat->flags & AVFMT_VARIABLE_FPS)))){
                    av_log(oc, AV_LOG_WARNING, "Frame rate very high for a muxer not efficiently supporting it.\n"
                                               "Please consider specifying a lower framerate, a different muxer or -vsync 2\n");
                }
                for (j = 0; j < ost->forced_kf_count; j++)
                    ost->forced_kf_pts[j] = av_rescale_q(ost->forced_kf_pts[j],
                                                         AV_TIME_BASE_Q,
                                                         codec->time_base);

                codec->width  = ost->filter->filter->inputs[0]->w;
                codec->height = ost->filter->filter->inputs[0]->h;
                codec->sample_aspect_ratio = ost->st->sample_aspect_ratio =
                    ost->frame_aspect_ratio ? // overridden by the -aspect cli option
                    av_d2q(ost->frame_aspect_ratio * codec->height/codec->width, 255) :
                    ost->filter->filter->inputs[0]->sample_aspect_ratio;
                codec->pix_fmt = ost->filter->filter->inputs[0]->format;

                if (!icodec ||
                    codec->width   != icodec->width  ||
                    codec->height  != icodec->height ||
                    codec->pix_fmt != icodec->pix_fmt) {
                    codec->bits_per_raw_sample = frame_bits_per_raw_sample;
                }

                if (ost->forced_keyframes)
                    parse_forced_key_frames(ost->forced_keyframes, ost,
                                            ost->st->codec);
                break;
            case AVMEDIA_TYPE_SUBTITLE:
                codec->time_base = (AVRational){1, 1000};
                if (!codec->width) {
                    codec->width     = input_streams[ost->source_index]->st->codec->width;
                    codec->height    = input_streams[ost->source_index]->st->codec->height;
                }
                break;
            default:
                abort();
                break;
            }
            /* two pass mode */
            if (codec->flags & (CODEC_FLAG_PASS1 | CODEC_FLAG_PASS2)) {
                char logfilename[1024];
                FILE *f;

                snprintf(logfilename, sizeof(logfilename), "%s-%d.log",
                         pass_logfilename_prefix ? pass_logfilename_prefix : DEFAULT_PASS_LOGFILENAME_PREFIX,
                         i);
                if (!strcmp(ost->enc->name, "libx264")) {
                    av_dict_set(&ost->opts, "stats", logfilename, AV_DICT_DONT_OVERWRITE);
                } else {
                    if (codec->flags & CODEC_FLAG_PASS2) {
                        char  *logbuffer;
                        size_t logbuffer_size;
                        if (cmdutils_read_file(logfilename, &logbuffer, &logbuffer_size) < 0) {
                            av_log(NULL, AV_LOG_FATAL, "Error reading log file '%s' for pass-2 encoding\n",
                                   logfilename);
                            exit_program(1);
                        }
                        codec->stats_in = logbuffer;
                    }
                    if (codec->flags & CODEC_FLAG_PASS1) {
                        f = fopen(logfilename, "wb");
                        if (!f) {
                            av_log(NULL, AV_LOG_FATAL, "Cannot write log file '%s' for pass-1 encoding: %s\n",
                                logfilename, strerror(errno));
                            exit_program(1);
                        }
                        ost->logfile = f;
                    }
                }
            }
        }
    }

    /* open each encoder */
    for (i = 0; i < nb_output_streams; i++) {
        ost = output_streams[i];
        if (ost->encoding_needed) {
            AVCodec      *codec = ost->enc;
            AVCodecContext *dec = NULL;

            if ((ist = get_input_stream(ost)))
                dec = ist->st->codec;
            if (dec && dec->subtitle_header) {
                /* ASS code assumes this buffer is null terminated so add extra byte. */
                ost->st->codec->subtitle_header = av_mallocz(dec->subtitle_header_size + 1);
                if (!ost->st->codec->subtitle_header) {
                    ret = AVERROR(ENOMEM);
                    goto dump_format;
                }
                memcpy(ost->st->codec->subtitle_header, dec->subtitle_header, dec->subtitle_header_size);
                ost->st->codec->subtitle_header_size = dec->subtitle_header_size;
            }
            if (!av_dict_get(ost->opts, "threads", NULL, 0))
                av_dict_set(&ost->opts, "threads", "auto", 0);
            if (avcodec_open2(ost->st->codec, codec, &ost->opts) < 0) {
                snprintf(error, sizeof(error), "Error while opening encoder for output stream #%d:%d - maybe incorrect parameters such as bit_rate, rate, width or height",
                        ost->file_index, ost->index);
                ret = AVERROR(EINVAL);
                goto dump_format;
            }
            if (ost->enc->type == AVMEDIA_TYPE_AUDIO &&
                !(ost->enc->capabilities & CODEC_CAP_VARIABLE_FRAME_SIZE))
                av_buffersink_set_frame_size(ost->filter->filter,
                                             ost->st->codec->frame_size);
            assert_codec_experimental(ost->st->codec, 1);
            assert_avoptions(ost->opts);
            if (ost->st->codec->bit_rate && ost->st->codec->bit_rate < 1000)
                av_log(NULL, AV_LOG_WARNING, "The bitrate parameter is set too low."
                                             " It takes bits/s as argument, not kbits/s\n");
            extra_size += ost->st->codec->extradata_size;

            if (ost->st->codec->me_threshold)
                input_streams[ost->source_index]->st->codec->debug |= FF_DEBUG_MV;
        }
    }

    /* init input streams */
    for (i = 0; i < nb_input_streams; i++)
        if ((ret = init_input_stream(i, error, sizeof(error))) < 0)
            goto dump_format;

    /* discard unused programs */
    for (i = 0; i < nb_input_files; i++) {
        InputFile *ifile = input_files[i];
        for (j = 0; j < ifile->ctx->nb_programs; j++) {
            AVProgram *p = ifile->ctx->programs[j];
            int discard  = AVDISCARD_ALL;

            for (k = 0; k < p->nb_stream_indexes; k++)
                if (!input_streams[ifile->ist_index + p->stream_index[k]]->discard) {
                    discard = AVDISCARD_DEFAULT;
                    break;
                }
            p->discard = discard;
        }
    }

    /* open files and write file headers */
    for (i = 0; i < nb_output_files; i++) {
        oc = output_files[i]->ctx;
        oc->interrupt_callback = int_cb;
        if ((ret = avformat_write_header(oc, &output_files[i]->opts)) < 0) {
            char errbuf[128];
            const char *errbuf_ptr = errbuf;
            if (av_strerror(ret, errbuf, sizeof(errbuf)) < 0)
                errbuf_ptr = strerror(AVUNERROR(ret));
            snprintf(error, sizeof(error), "Could not write header for output file #%d (incorrect codec parameters ?): %s", i, errbuf_ptr);
            ret = AVERROR(EINVAL);
            goto dump_format;
        }
//         assert_avoptions(output_files[i]->opts);
        if (strcmp(oc->oformat->name, "rtp")) {
            want_sdp = 0;
        }
    }

 dump_format:
    /* dump the file output parameters - cannot be done before in case
       of stream copy */
    for (i = 0; i < nb_output_files; i++) {
        av_dump_format(output_files[i]->ctx, i, output_files[i]->ctx->filename, 1);
    }

    /* dump the stream mapping */
    av_log(NULL, AV_LOG_INFO, "Stream mapping:\n");
    for (i = 0; i < nb_input_streams; i++) {
        ist = input_streams[i];

        for (j = 0; j < ist->nb_filters; j++) {
            if (ist->filters[j]->graph->graph_desc) {
                av_log(NULL, AV_LOG_INFO, "  Stream #%d:%d (%s) -> %s",
                       ist->file_index, ist->st->index, ist->dec ? ist->dec->name : "?",
                       ist->filters[j]->name);
                if (nb_filtergraphs > 1)
                    av_log(NULL, AV_LOG_INFO, " (graph %d)", ist->filters[j]->graph->index);
                av_log(NULL, AV_LOG_INFO, "\n");
            }
        }
    }

    for (i = 0; i < nb_output_streams; i++) {
        ost = output_streams[i];

        if (ost->attachment_filename) {
            /* an attached file */
            av_log(NULL, AV_LOG_INFO, "  File %s -> Stream #%d:%d\n",
                   ost->attachment_filename, ost->file_index, ost->index);
            continue;
        }

        if (ost->filter && ost->filter->graph->graph_desc) {
            /* output from a complex graph */
            av_log(NULL, AV_LOG_INFO, "  %s", ost->filter->name);
            if (nb_filtergraphs > 1)
                av_log(NULL, AV_LOG_INFO, " (graph %d)", ost->filter->graph->index);

            av_log(NULL, AV_LOG_INFO, " -> Stream #%d:%d (%s)\n", ost->file_index,
                   ost->index, ost->enc ? ost->enc->name : "?");
            continue;
        }

        av_log(NULL, AV_LOG_INFO, "  Stream #%d:%d -> #%d:%d",
               input_streams[ost->source_index]->file_index,
               input_streams[ost->source_index]->st->index,
               ost->file_index,
               ost->index);
        if (ost->sync_ist != input_streams[ost->source_index])
            av_log(NULL, AV_LOG_INFO, " [sync #%d:%d]",
                   ost->sync_ist->file_index,
                   ost->sync_ist->st->index);
        if (ost->stream_copy)
            av_log(NULL, AV_LOG_INFO, " (copy)");
        else
            av_log(NULL, AV_LOG_INFO, " (%s -> %s)", input_streams[ost->source_index]->dec ?
                   input_streams[ost->source_index]->dec->name : "?",
                   ost->enc ? ost->enc->name : "?");
        av_log(NULL, AV_LOG_INFO, "\n");
    }

    if (ret) {
        av_log(NULL, AV_LOG_ERROR, "%s\n", error);
        return ret;
    }

    if (want_sdp) {
        print_sdp();
    }

    return 0;
}

/**
 * @return 1 if there are still streams where more output is wanted,
 *         0 otherwise
 */
static int need_output(void)
{
    int i;

    for (i = 0; i < nb_output_streams; i++) {
        OutputStream *ost    = output_streams[i];
        OutputFile *of       = output_files[ost->file_index];
        AVFormatContext *os  = output_files[ost->file_index]->ctx;

        if (ost->finished ||
            (os->pb && avio_tell(os->pb) >= of->limit_filesize))
            continue;
        if (ost->frame_number >= ost->max_frames) {
            int j;
            for (j = 0; j < of->ctx->nb_streams; j++)
                output_streams[of->ost_index + j]->finished = 1;
            continue;
        }

        return 1;
    }

    return 0;
}

/**
 * Select the output stream to process.
 *
 * @return  selected output stream, or NULL if none available
 */
static OutputStream *choose_output(void)
{
    int i;
    int64_t opts_min = INT64_MAX;
    OutputStream *ost_min = NULL;

    for (i = 0; i < nb_output_streams; i++) {
        OutputStream *ost = output_streams[i];
        int64_t opts = av_rescale_q(ost->st->cur_dts, ost->st->time_base,
                                    AV_TIME_BASE_Q);
        if (!ost->unavailable && !ost->finished && opts < opts_min) {
            opts_min = opts;
            ost_min  = ost;
        }
    }
    return ost_min;
}

static int check_keyboard_interaction(int64_t cur_time)
{
    int i, ret, key;
    static int64_t last_time;
    if (received_nb_signals)
        return AVERROR_EXIT;
    /* read_key() returns 0 on EOF */
    if(cur_time - last_time >= 100000 && !run_as_daemon){
        key =  read_key();
        last_time = cur_time;
    }else
        key = -1;
    if (key == 'q')
        return AVERROR_EXIT;
    if (key == '+') av_log_set_level(av_log_get_level()+10);
    if (key == '-') av_log_set_level(av_log_get_level()-10);
    if (key == 's') qp_hist     ^= 1;
    if (key == 'h'){
        if (do_hex_dump){
            do_hex_dump = do_pkt_dump = 0;
        } else if(do_pkt_dump){
            do_hex_dump = 1;
        } else
            do_pkt_dump = 1;
        av_log_set_level(AV_LOG_DEBUG);
    }
    if (key == 'c' || key == 'C'){
        char buf[4096], target[64], command[256], arg[256] = {0};
        double time;
        int k, n = 0;
        fprintf(stderr, "\nEnter command: <target> <time> <command>[ <argument>]\n");
        i = 0;
        while ((k = read_key()) != '\n' && k != '\r' && i < sizeof(buf)-1)
            if (k > 0)
                buf[i++] = k;
        buf[i] = 0;
        if (k > 0 &&
            (n = sscanf(buf, "%63[^ ] %lf %255[^ ] %255[^\n]", target, &time, command, arg)) >= 3) {
            av_log(NULL, AV_LOG_DEBUG, "Processing command target:%s time:%f command:%s arg:%s",
                   target, time, command, arg);
            for (i = 0; i < nb_filtergraphs; i++) {
                FilterGraph *fg = filtergraphs[i];
                if (fg->graph) {
                    if (time < 0) {
                        ret = avfilter_graph_send_command(fg->graph, target, command, arg, buf, sizeof(buf),
                                                          key == 'c' ? AVFILTER_CMD_FLAG_ONE : 0);
                        fprintf(stderr, "Command reply for stream %d: ret:%d res:%s\n", i, ret, buf);
                    } else {
                        ret = avfilter_graph_queue_command(fg->graph, target, command, arg, 0, time);
                    }
                }
            }
        } else {
            av_log(NULL, AV_LOG_ERROR,
                   "Parse error, at least 3 arguments were expected, "
                   "only %d given in string '%s'\n", n, buf);
        }
    }
    if (key == 'd' || key == 'D'){
        int debug=0;
        if(key == 'D') {
            debug = input_streams[0]->st->codec->debug<<1;
            if(!debug) debug = 1;
            while(debug & (FF_DEBUG_DCT_COEFF|FF_DEBUG_VIS_QP|FF_DEBUG_VIS_MB_TYPE)) //unsupported, would just crash
                debug += debug;
        }else
            if(scanf("%d", &debug)!=1)
                fprintf(stderr,"error parsing debug value\n");
        for(i=0;i<nb_input_streams;i++) {
            input_streams[i]->st->codec->debug = debug;
        }
        for(i=0;i<nb_output_streams;i++) {
            OutputStream *ost = output_streams[i];
            ost->st->codec->debug = debug;
        }
        if(debug) av_log_set_level(AV_LOG_DEBUG);
        fprintf(stderr,"debug=%d\n", debug);
    }
    if (key == '?'){
        fprintf(stderr, "key    function\n"
                        "?      show this help\n"
                        "+      increase verbosity\n"
                        "-      decrease verbosity\n"
                        "c      Send command to filtergraph\n"
                        "D      cycle through available debug modes\n"
                        "h      dump packets/hex press to cycle through the 3 states\n"
                        "q      quit\n"
                        "s      Show QP histogram\n"
        );
    }
    return 0;
}

#if HAVE_PTHREADS
static void *input_thread(void *arg)
{
    InputFile *f = arg;
    int ret = 0;

    while (!transcoding_finished && ret >= 0) {
        AVPacket pkt;
        ret = av_read_frame(f->ctx, &pkt);

        if (ret == AVERROR(EAGAIN)) {
            av_usleep(10000);
            ret = 0;
            continue;
        } else if (ret < 0)
            break;

        pthread_mutex_lock(&f->fifo_lock);
        while (!av_fifo_space(f->fifo))
            pthread_cond_wait(&f->fifo_cond, &f->fifo_lock);

        av_dup_packet(&pkt);
        av_fifo_generic_write(f->fifo, &pkt, sizeof(pkt), NULL);

        pthread_mutex_unlock(&f->fifo_lock);
    }

    f->finished = 1;
    return NULL;
}

static void free_input_threads(void)
{
    int i;

    if (nb_input_files == 1)
        return;

    transcoding_finished = 1;

    for (i = 0; i < nb_input_files; i++) {
        InputFile *f = input_files[i];
        AVPacket pkt;

        if (!f->fifo || f->joined)
            continue;

        pthread_mutex_lock(&f->fifo_lock);
        while (av_fifo_size(f->fifo)) {
            av_fifo_generic_read(f->fifo, &pkt, sizeof(pkt), NULL);
            av_free_packet(&pkt);
        }
        pthread_cond_signal(&f->fifo_cond);
        pthread_mutex_unlock(&f->fifo_lock);

        pthread_join(f->thread, NULL);
        f->joined = 1;

        while (av_fifo_size(f->fifo)) {
            av_fifo_generic_read(f->fifo, &pkt, sizeof(pkt), NULL);
            av_free_packet(&pkt);
        }
        av_fifo_free(f->fifo);
    }
}

static int init_input_threads(void)
{
    int i, ret;

    if (nb_input_files == 1)
        return 0;

    for (i = 0; i < nb_input_files; i++) {
        InputFile *f = input_files[i];

        if (!(f->fifo = av_fifo_alloc(8*sizeof(AVPacket))))
            return AVERROR(ENOMEM);

        pthread_mutex_init(&f->fifo_lock, NULL);
        pthread_cond_init (&f->fifo_cond, NULL);

        if ((ret = pthread_create(&f->thread, NULL, input_thread, f)))
            return AVERROR(ret);
    }
    return 0;
}

static int get_input_packet_mt(InputFile *f, AVPacket *pkt)
{
    int ret = 0;

    pthread_mutex_lock(&f->fifo_lock);

    if (av_fifo_size(f->fifo)) {
        av_fifo_generic_read(f->fifo, pkt, sizeof(*pkt), NULL);
        pthread_cond_signal(&f->fifo_cond);
    } else {
        if (f->finished)
            ret = AVERROR_EOF;
        else
            ret = AVERROR(EAGAIN);
    }

    pthread_mutex_unlock(&f->fifo_lock);

    return ret;
}
#endif

static int get_input_packet(InputFile *f, AVPacket *pkt)
{
#if HAVE_PTHREADS
    if (nb_input_files > 1)
        return get_input_packet_mt(f, pkt);
#endif
    return av_read_frame(f->ctx, pkt);
}

static int got_eagain(void)
{
    int i;
    for (i = 0; i < nb_output_streams; i++)
        if (output_streams[i]->unavailable)
            return 1;
    return 0;
}

static void reset_eagain(void)
{
    int i;
    for (i = 0; i < nb_input_files; i++)
        input_files[i]->eagain = 0;
    for (i = 0; i < nb_output_streams; i++)
        output_streams[i]->unavailable = 0;
}

static void close_output_stream(OutputStream *ost)
{
    OutputFile *of = output_files[ost->file_index];

    ost->finished = 1;
    if (of->shortest) {
        int i;
        for (i = 0; i < of->ctx->nb_streams; i++)
            output_streams[of->ost_index + i]->finished = 1;
    }
}

/**
 * @return
 * - 0 -- one packet was read and processed
 * - AVERROR(EAGAIN) -- no packets were available for selected file,
 *   this function should be called again
 * - AVERROR_EOF -- this function should not be called again
 */
static int process_input(int file_index)
{
    InputFile *ifile = input_files[file_index];
    AVFormatContext *is;
    InputStream *ist;
    AVPacket pkt;
    int ret, i, j;

    is  = ifile->ctx;
    ret = get_input_packet(ifile, &pkt);

    if (ret == AVERROR(EAGAIN)) {
        ifile->eagain = 1;
        return ret;
    }
    if (ret < 0) {
        if (ret != AVERROR_EOF) {
            print_error(is->filename, ret);
            if (exit_on_error)
                exit_program(1);
        }
        ifile->eof_reached = 1;

        for (i = 0; i < ifile->nb_streams; i++) {
            ist = input_streams[ifile->ist_index + i];
            if (ist->decoding_needed)
                output_packet(ist, NULL);

            /* mark all outputs that don't go through lavfi as finished */
            for (j = 0; j < nb_output_streams; j++) {
                OutputStream *ost = output_streams[j];

                if (ost->source_index == ifile->ist_index + i &&
                    (ost->stream_copy || ost->enc->type == AVMEDIA_TYPE_SUBTITLE))
                    close_output_stream(ost);
            }
        }

        return AVERROR(EAGAIN);
    }

    reset_eagain();

    if (do_pkt_dump) {
        av_pkt_dump_log2(NULL, AV_LOG_DEBUG, &pkt, do_hex_dump,
                         is->streams[pkt.stream_index]);
    }
    /* the following test is needed in case new streams appear
       dynamically in stream : we ignore them */
    if (pkt.stream_index >= ifile->nb_streams) {
        report_new_stream(file_index, &pkt);
        goto discard_packet;
    }

    ist = input_streams[ifile->ist_index + pkt.stream_index];
    if (ist->discard)
        goto discard_packet;

    if(!ist->wrap_correction_done && input_files[file_index]->ctx->start_time != AV_NOPTS_VALUE && ist->st->pts_wrap_bits < 64){
        uint64_t stime = av_rescale_q(input_files[file_index]->ctx->start_time, AV_TIME_BASE_Q, ist->st->time_base);
        uint64_t stime2= stime + (1LL<<ist->st->pts_wrap_bits);
        ist->wrap_correction_done = 1;
        if(pkt.dts != AV_NOPTS_VALUE && pkt.dts > stime && pkt.dts - stime > stime2 - pkt.dts) {
            pkt.dts -= 1LL<<ist->st->pts_wrap_bits;
            ist->wrap_correction_done = 0;
        }
        if(pkt.pts != AV_NOPTS_VALUE && pkt.pts > stime && pkt.pts - stime > stime2 - pkt.pts) {
            pkt.pts -= 1LL<<ist->st->pts_wrap_bits;
            ist->wrap_correction_done = 0;
        }
    }

    if (pkt.dts != AV_NOPTS_VALUE)
        pkt.dts += av_rescale_q(ifile->ts_offset, AV_TIME_BASE_Q, ist->st->time_base);
    if (pkt.pts != AV_NOPTS_VALUE)
        pkt.pts += av_rescale_q(ifile->ts_offset, AV_TIME_BASE_Q, ist->st->time_base);

    if (pkt.pts != AV_NOPTS_VALUE)
        pkt.pts *= ist->ts_scale;
    if (pkt.dts != AV_NOPTS_VALUE)
        pkt.dts *= ist->ts_scale;

    if (debug_ts) {
        av_log(NULL, AV_LOG_INFO, "demuxer -> ist_index:%d type:%s "
                "next_dts:%s next_dts_time:%s next_pts:%s next_pts_time:%s  pkt_pts:%s pkt_pts_time:%s pkt_dts:%s pkt_dts_time:%s off:%"PRId64"\n",
                ifile->ist_index + pkt.stream_index, av_get_media_type_string(ist->st->codec->codec_type),
                av_ts2str(ist->next_dts), av_ts2timestr(ist->next_dts, &AV_TIME_BASE_Q),
                av_ts2str(ist->next_pts), av_ts2timestr(ist->next_pts, &AV_TIME_BASE_Q),
                av_ts2str(pkt.pts), av_ts2timestr(pkt.pts, &ist->st->time_base),
                av_ts2str(pkt.dts), av_ts2timestr(pkt.dts, &ist->st->time_base),
                input_files[ist->file_index]->ts_offset);
    }

    if (pkt.dts != AV_NOPTS_VALUE && ist->next_dts != AV_NOPTS_VALUE &&
        !copy_ts) {
        int64_t pkt_dts = av_rescale_q(pkt.dts, ist->st->time_base, AV_TIME_BASE_Q);
        int64_t delta   = pkt_dts - ist->next_dts;
        if (is->iformat->flags & AVFMT_TS_DISCONT) {
        if(delta < -1LL*dts_delta_threshold*AV_TIME_BASE ||
            (delta > 1LL*dts_delta_threshold*AV_TIME_BASE &&
                ist->st->codec->codec_type != AVMEDIA_TYPE_SUBTITLE) ||
            pkt_dts+1<ist->pts){
            ifile->ts_offset -= delta;
            av_log(NULL, AV_LOG_DEBUG,
                   "timestamp discontinuity %"PRId64", new offset= %"PRId64"\n",
                   delta, ifile->ts_offset);
            pkt.dts -= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
            if (pkt.pts != AV_NOPTS_VALUE)
                pkt.pts -= av_rescale_q(delta, AV_TIME_BASE_Q, ist->st->time_base);
        }
        } else {
            if ( delta < -1LL*dts_error_threshold*AV_TIME_BASE ||
                (delta > 1LL*dts_error_threshold*AV_TIME_BASE && ist->st->codec->codec_type != AVMEDIA_TYPE_SUBTITLE)
               ) {
                av_log(NULL, AV_LOG_WARNING, "DTS %"PRId64", next:%"PRId64" st:%d invalid dropping\n", pkt.dts, ist->next_dts, pkt.stream_index);
                pkt.dts = AV_NOPTS_VALUE;
            }
            if (pkt.pts != AV_NOPTS_VALUE){
                int64_t pkt_pts = av_rescale_q(pkt.pts, ist->st->time_base, AV_TIME_BASE_Q);
                delta   = pkt_pts - ist->next_dts;
                if ( delta < -1LL*dts_error_threshold*AV_TIME_BASE ||
                    (delta > 1LL*dts_error_threshold*AV_TIME_BASE && ist->st->codec->codec_type != AVMEDIA_TYPE_SUBTITLE)
                   ) {
                    av_log(NULL, AV_LOG_WARNING, "PTS %"PRId64", next:%"PRId64" invalid dropping st:%d\n", pkt.pts, ist->next_dts, pkt.stream_index);
                    pkt.pts = AV_NOPTS_VALUE;
                }
            }
        }
    }

    sub2video_heartbeat(ist, pkt.pts);

    ret = output_packet(ist, &pkt);
    if (ret < 0) {
        char buf[128];
        av_strerror(ret, buf, sizeof(buf));
        av_log(NULL, AV_LOG_ERROR, "Error while decoding stream #%d:%d: %s\n",
                ist->file_index, ist->st->index, buf);
        if (exit_on_error)
            exit_program(1);
    }

discard_packet:
    av_free_packet(&pkt);

    return 0;
}

/**
 * Perform a step of transcoding for the specified filter graph.
 *
 * @param[in]  graph     filter graph to consider
 * @param[out] best_ist  input stream where a frame would allow to continue
 * @return  0 for success, <0 for error
 */
static int transcode_from_filter(FilterGraph *graph, InputStream **best_ist)
{
    int i, ret;
    int nb_requests, nb_requests_max = 0;
    InputFilter *ifilter;
    InputStream *ist;

    *best_ist = NULL;
    ret = avfilter_graph_request_oldest(graph->graph);
    if (ret >= 0)
        return reap_filters();

    if (ret == AVERROR_EOF) {
        ret = reap_filters();
        for (i = 0; i < graph->nb_outputs; i++)
            close_output_stream(graph->outputs[i]->ost);
        return ret;
    }
    if (ret != AVERROR(EAGAIN))
        return ret;

    for (i = 0; i < graph->nb_inputs; i++) {
        ifilter = graph->inputs[i];
        ist = ifilter->ist;
        if (input_files[ist->file_index]->eagain ||
            input_files[ist->file_index]->eof_reached)
            continue;
        nb_requests = av_buffersrc_get_nb_failed_requests(ifilter->filter);
        if (nb_requests > nb_requests_max) {
            nb_requests_max = nb_requests;
            *best_ist = ist;
        }
    }

    if (!*best_ist)
        for (i = 0; i < graph->nb_outputs; i++)
            graph->outputs[i]->ost->unavailable = 1;

    return 0;
}

/**
 * Run a single step of transcoding.
 *
 * @return  0 for success, <0 for error
 */
static int transcode_step(void)
{
    OutputStream *ost;
    InputStream  *ist;
    int ret;

    ost = choose_output();
    if (!ost) {
        if (got_eagain()) {
            reset_eagain();
            av_usleep(10000);
            return 0;
        }
        av_log(NULL, AV_LOG_VERBOSE, "No more inputs to read from, finishing.\n");
        return AVERROR_EOF;
    }

    if (ost->filter) {
        if ((ret = transcode_from_filter(ost->filter->graph, &ist)) < 0)
            return ret;
        if (!ist)
            return 0;
    } else {
        av_assert0(ost->source_index >= 0);
        ist = input_streams[ost->source_index];
    }

    ret = process_input(ist->file_index);
    if (ret == AVERROR(EAGAIN)) {
        if (input_files[ist->file_index]->eagain)
            ost->unavailable = 1;
        return 0;
    }
    if (ret < 0)
        return ret == AVERROR_EOF ? 0 : ret;

    return reap_filters();
}

/*
 * The following code is the main loop of the file converter
 */
static int transcode(void)
{
    int ret, i;
    AVFormatContext *os;
    OutputStream *ost;
    InputStream *ist;
    int64_t timer_start;

    ret = transcode_init();
    if (ret < 0)
        goto fail;

    if (stdin_interaction) {
        av_log(NULL, AV_LOG_INFO, "Press [q] to stop, [?] for help\n");
    }

    timer_start = av_gettime();

#if HAVE_PTHREADS
    if ((ret = init_input_threads()) < 0)
        goto fail;
#endif

    while (!received_sigterm) {
        int64_t cur_time= av_gettime();

        /* if 'q' pressed, exits */
        if (stdin_interaction)
            if (check_keyboard_interaction(cur_time) < 0)
                break;

        /* check if there's any stream where output is still needed */
        if (!need_output()) {
            av_log(NULL, AV_LOG_VERBOSE, "No more output streams to write to, finishing.\n");
            break;
        }

        ret = transcode_step();
        if (ret < 0) {
            if (ret == AVERROR_EOF || ret == AVERROR(EAGAIN))
                continue;

            av_log(NULL, AV_LOG_ERROR, "Error while filtering.\n");
            break;
        }

        /* dump report by using the output first video and audio streams */
        print_report(0, timer_start, cur_time);
    }
#if HAVE_PTHREADS
    free_input_threads();
#endif

    /* at the end of stream, we must flush the decoder buffers */
    for (i = 0; i < nb_input_streams; i++) {
        ist = input_streams[i];
        if (!input_files[ist->file_index]->eof_reached && ist->decoding_needed) {
            output_packet(ist, NULL);
        }
    }
    flush_encoders();

    term_exit();

    /* write the trailer if needed and close file */
    for (i = 0; i < nb_output_files; i++) {
        os = output_files[i]->ctx;
        av_write_trailer(os);
    }

    /* dump report by using the first video and audio streams */
    print_report(1, timer_start, av_gettime());

    /* close each encoder */
    for (i = 0; i < nb_output_streams; i++) {