ffmpeg.c

        if (in_picture->interlaced_frame) {
            if (enc->codec->id == AV_CODEC_ID_MJPEG)
                mux_enc->field_order = in_picture->top_field_first ? AV_FIELD_TT:AV_FIELD_BB;
            else
                mux_enc->field_order = in_picture->top_field_first ? AV_FIELD_TB:AV_FIELD_BT;
        } else
            mux_enc->field_order = AV_FIELD_PROGRESSIVE;

        in_picture->quality = enc->global_quality;
        if (!enc->me_threshold)
            in_picture->pict_type = 0;

        pts_time = in_picture->pts != AV_NOPTS_VALUE ?
            in_picture->pts * av_q2d(enc->time_base) : NAN;
        if (ost->forced_kf_index < ost->forced_kf_count &&
            in_picture->pts >= ost->forced_kf_pts[ost->forced_kf_index]) {
            ost->forced_kf_index++;
            forced_keyframe = 1;
        } else if (ost->forced_keyframes_pexpr) {
            double res;
            ost->forced_keyframes_expr_const_values[FKF_T] = pts_time;
            res = av_expr_eval(ost->forced_keyframes_pexpr,
                               ost->forced_keyframes_expr_const_values, NULL);
            av_dlog(NULL, "force_key_frame: n:%f n_forced:%f prev_forced_n:%f t:%f prev_forced_t:%f -> res:%f\n",
                    ost->forced_keyframes_expr_const_values[FKF_N],
                    ost->forced_keyframes_expr_const_values[FKF_N_FORCED],
                    ost->forced_keyframes_expr_const_values[FKF_PREV_FORCED_N],
                    ost->forced_keyframes_expr_const_values[FKF_T],
                    ost->forced_keyframes_expr_const_values[FKF_PREV_FORCED_T],
                    res);
            if (res) {
                forced_keyframe = 1;
                ost->forced_keyframes_expr_const_values[FKF_PREV_FORCED_N] =
                    ost->forced_keyframes_expr_const_values[FKF_N];
                ost->forced_keyframes_expr_const_values[FKF_PREV_FORCED_T] =
                    ost->forced_keyframes_expr_const_values[FKF_T];
                ost->forced_keyframes_expr_const_values[FKF_N_FORCED] += 1;
            }

            ost->forced_keyframes_expr_const_values[FKF_N] += 1;
        }

        if (forced_keyframe) {
            in_picture->pict_type = AV_PICTURE_TYPE_I;
            av_log(NULL, AV_LOG_DEBUG, "Forced keyframe at time %f\n", pts_time);
        }

        update_benchmark(NULL);
        if (debug_ts) {
            av_log(NULL, AV_LOG_INFO, "encoder <- type:video "
                   "frame_pts:%s frame_pts_time:%s time_base:%d/%d\n",
                   av_ts2str(in_picture->pts), av_ts2timestr(in_picture->pts, &enc->time_base),
                   enc->time_base.num, enc->time_base.den);
        }

        ost->frames_encoded++;

        ret = avcodec_encode_video2(enc, &pkt, in_picture, &got_packet);
        update_benchmark("encode_video %d.%d", ost->file_index, ost->index);
        if (ret < 0) {
            av_log(NULL, AV_LOG_FATAL, "Video encoding failed\n");
            exit_program(1);
        }

        if (got_packet) {
            if (debug_ts) {
                av_log(NULL, AV_LOG_INFO, "encoder -> type:video "
                       "pkt_pts:%s pkt_pts_time:%s pkt_dts:%s pkt_dts_time:%s\n",
                       av_ts2str(pkt.pts), av_ts2timestr(pkt.pts, &enc->time_base),
                       av_ts2str(pkt.dts), av_ts2timestr(pkt.dts, &enc->time_base));
            }

            if (pkt.pts == AV_NOPTS_VALUE && !(enc->codec->capabilities & CODEC_CAP_DELAY))
                pkt.pts = ost->sync_opts;

            av_packet_rescale_ts(&pkt, enc->time_base, ost->st->time_base);

            if (debug_ts) {
                av_log(NULL, AV_LOG_INFO, "encoder -> type:video "
                    "pkt_pts:%s pkt_pts_time:%s pkt_dts:%s pkt_dts_time:%s\n",
                    av_ts2str(pkt.pts), av_ts2timestr(pkt.pts, &ost->st->time_base),
                    av_ts2str(pkt.dts), av_ts2timestr(pkt.dts, &ost->st->time_base));
            }

            frame_size = pkt.size;
            write_frame(s, &pkt, ost);

            /* if two pass, output log */
            if (ost->logfile && enc->stats_out) {
                fprintf(ost->logfile, "%s", enc->stats_out);
            }
        }
    }
    ost->sync_opts++;
    /*
     * For video, number of frames in == number of packets out.
     * But there may be reordering, so we can't throw away frames on encoder
     * flush, we need to limit them here, before they go into encoder.
     */
    ost->frame_number++;

    if (vstats_filename && frame_size)
        do_video_stats(ost, frame_size);
  }
}

static double psnr(double d)
{
    return -10.0 * log(d) / log(10.0);
}

static void do_video_stats(OutputStream *ost, int frame_size)
{
    AVCodecContext *enc;
    int frame_number;
    double ti1, bitrate, avg_bitrate;

    /* this is executed just the first time do_video_stats is called */
    if (!vstats_file) {
        vstats_file = fopen(vstats_filename, "w");
        if (!vstats_file) {
            perror("fopen");
            exit_program(1);
        }
    }

    enc = ost->enc_ctx;
    if (enc->codec_type == AVMEDIA_TYPE_VIDEO) {
        frame_number = ost->st->nb_frames;
        fprintf(vstats_file, "frame= %5d q= %2.1f ", frame_number, enc->coded_frame->quality / (float)FF_QP2LAMBDA);
        if (enc->flags&CODEC_FLAG_PSNR)
            fprintf(vstats_file, "PSNR= %6.2f ", psnr(enc->coded_frame->error[0] / (enc->width * enc->height * 255.0 * 255.0)));

        fprintf(vstats_file,"f_size= %6d ", frame_size);
        /* compute pts value */
        ti1 = av_stream_get_end_pts(ost->st) * av_q2d(ost->st->time_base);
        if (ti1 < 0.01)
            ti1 = 0.01;

        bitrate     = (frame_size * 8) / av_q2d(enc->time_base) / 1000.0;
        avg_bitrate = (double)(ost->data_size * 8) / ti1 / 1000.0;
        fprintf(vstats_file, "s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s ",
               (double)ost->data_size / 1024, ti1, bitrate, avg_bitrate);
        fprintf(vstats_file, "type= %c\n", av_get_picture_type_char(enc->coded_frame->pict_type));
    }
}

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

    ost->finished = ENCODER_FINISHED | MUXER_FINISHED;

    if (of->shortest) {
        for (i = 0; i < of->ctx->nb_streams; i++)
            output_streams[of->ost_index + i]->finished = ENCODER_FINISHED | MUXER_FINISHED;
    }
}

/**
 * Get and encode new output from any of the filtergraphs, without causing
 * activity.
 *
 * @return  0 for success, <0 for severe errors
 */
static int reap_filters(void)
{
    AVFrame *filtered_frame = NULL;
    int i;
    int64_t frame_pts;

    /* Reap all buffers present in the buffer sinks */
    for (i = 0; i < nb_output_streams; i++) {
        OutputStream *ost = output_streams[i];
        OutputFile    *of = output_files[ost->file_index];
        AVFilterContext *filter;
        AVCodecContext *enc = ost->enc_ctx;
        int ret = 0;

        if (!ost->filter)
            continue;
        filter = ost->filter->filter;

        if (!ost->filtered_frame && !(ost->filtered_frame = av_frame_alloc())) {
            return AVERROR(ENOMEM);
        }
        filtered_frame = ost->filtered_frame;

        while (1) {
            ret = av_buffersink_get_frame_flags(filter, filtered_frame,
                                               AV_BUFFERSINK_FLAG_NO_REQUEST);
            if (ret < 0) {
                if (ret != AVERROR(EAGAIN) && ret != AVERROR_EOF) {
                    av_log(NULL, AV_LOG_WARNING,
                           "Error in av_buffersink_get_frame_flags(): %s\n", av_err2str(ret));
                }
                break;
            }
            if (ost->finished) {
                av_frame_unref(filtered_frame);
                continue;
            }
            frame_pts = AV_NOPTS_VALUE;
            if (filtered_frame->pts != AV_NOPTS_VALUE) {
                int64_t start_time = (of->start_time == AV_NOPTS_VALUE) ? 0 : of->start_time;
                filtered_frame->pts = frame_pts =
                    av_rescale_q(filtered_frame->pts, filter->inputs[0]->time_base, enc->time_base) -
                    av_rescale_q(start_time, AV_TIME_BASE_Q, enc->time_base);
            }
            //if (ost->source_index >= 0)
            //    *filtered_frame= *input_streams[ost->source_index]->decoded_frame; //for me_threshold

            switch (filter->inputs[0]->type) {
            case AVMEDIA_TYPE_VIDEO:
                filtered_frame->pts = frame_pts;
                if (!ost->frame_aspect_ratio.num)
                    enc->sample_aspect_ratio = filtered_frame->sample_aspect_ratio;

                if (debug_ts) {
                    av_log(NULL, AV_LOG_INFO, "filter -> pts:%s pts_time:%s time_base:%d/%d\n",
                            av_ts2str(filtered_frame->pts), av_ts2timestr(filtered_frame->pts, &enc->time_base),
                            enc->time_base.num, enc->time_base.den);
                }

                do_video_out(of->ctx, ost, filtered_frame);
                break;
            case AVMEDIA_TYPE_AUDIO:
                filtered_frame->pts = frame_pts;
                if (!(enc->codec->capabilities & CODEC_CAP_PARAM_CHANGE) &&
                    enc->channels != av_frame_get_channels(filtered_frame)) {
                    av_log(NULL, AV_LOG_ERROR,
                           "Audio filter graph output is not normalized and encoder does not support parameter changes\n");
                    break;
                }
                do_audio_out(of->ctx, ost, filtered_frame);
                break;
            default:
                // TODO support subtitle filters
                av_assert0(0);
            }

            av_frame_unref(filtered_frame);
        }
    }

    return 0;
}

static void print_final_stats(int64_t total_size)
{
    uint64_t video_size = 0, audio_size = 0, extra_size = 0, other_size = 0;
    uint64_t subtitle_size = 0;
    uint64_t data_size = 0;
    float percent = -1.0;
    int i, j;

    for (i = 0; i < nb_output_streams; i++) {
        OutputStream *ost = output_streams[i];
        switch (ost->enc_ctx->codec_type) {
            case AVMEDIA_TYPE_VIDEO: video_size += ost->data_size; break;
            case AVMEDIA_TYPE_AUDIO: audio_size += ost->data_size; break;
            case AVMEDIA_TYPE_SUBTITLE: subtitle_size += ost->data_size; break;
            default:                 other_size += ost->data_size; break;
        }
        extra_size += ost->enc_ctx->extradata_size;
        data_size  += ost->data_size;
    }

    if (data_size && total_size>0 && total_size >= data_size)
        percent = 100.0 * (total_size - data_size) / data_size;

    av_log(NULL, AV_LOG_INFO, "\n");
    av_log(NULL, AV_LOG_INFO, "video:%1.0fkB audio:%1.0fkB subtitle:%1.0fkB other streams:%1.0fkB global headers:%1.0fkB muxing overhead: ",
           video_size / 1024.0,
           audio_size / 1024.0,
           subtitle_size / 1024.0,
           other_size / 1024.0,
           extra_size / 1024.0);
    if (percent >= 0.0)
        av_log(NULL, AV_LOG_INFO, "%f%%", percent);
    else
        av_log(NULL, AV_LOG_INFO, "unknown");
    av_log(NULL, AV_LOG_INFO, "\n");

    /* print verbose per-stream stats */
    for (i = 0; i < nb_input_files; i++) {
        InputFile *f = input_files[i];
        uint64_t total_packets = 0, total_size = 0;

        av_log(NULL, AV_LOG_VERBOSE, "Input file #%d (%s):\n",
               i, f->ctx->filename);

        for (j = 0; j < f->nb_streams; j++) {
            InputStream *ist = input_streams[f->ist_index + j];
            enum AVMediaType type = ist->dec_ctx->codec_type;

            total_size    += ist->data_size;
            total_packets += ist->nb_packets;

            av_log(NULL, AV_LOG_VERBOSE, "  Input stream #%d:%d (%s): ",
                   i, j, media_type_string(type));
            av_log(NULL, AV_LOG_VERBOSE, "%"PRIu64" packets read (%"PRIu64" bytes); ",
                   ist->nb_packets, ist->data_size);

            if (ist->decoding_needed) {
                av_log(NULL, AV_LOG_VERBOSE, "%"PRIu64" frames decoded",
                       ist->frames_decoded);
                if (type == AVMEDIA_TYPE_AUDIO)
                    av_log(NULL, AV_LOG_VERBOSE, " (%"PRIu64" samples)", ist->samples_decoded);
                av_log(NULL, AV_LOG_VERBOSE, "; ");
            }

            av_log(NULL, AV_LOG_VERBOSE, "\n");
        }

        av_log(NULL, AV_LOG_VERBOSE, "  Total: %"PRIu64" packets (%"PRIu64" bytes) demuxed\n",
               total_packets, total_size);
    }

    for (i = 0; i < nb_output_files; i++) {
        OutputFile *of = output_files[i];
        uint64_t total_packets = 0, total_size = 0;

        av_log(NULL, AV_LOG_VERBOSE, "Output file #%d (%s):\n",
               i, of->ctx->filename);

        for (j = 0; j < of->ctx->nb_streams; j++) {
            OutputStream *ost = output_streams[of->ost_index + j];
            enum AVMediaType type = ost->enc_ctx->codec_type;

            total_size    += ost->data_size;
            total_packets += ost->packets_written;

            av_log(NULL, AV_LOG_VERBOSE, "  Output stream #%d:%d (%s): ",
                   i, j, media_type_string(type));
            if (ost->encoding_needed) {
                av_log(NULL, AV_LOG_VERBOSE, "%"PRIu64" frames encoded",
                       ost->frames_encoded);
                if (type == AVMEDIA_TYPE_AUDIO)
                    av_log(NULL, AV_LOG_VERBOSE, " (%"PRIu64" samples)", ost->samples_encoded);
                av_log(NULL, AV_LOG_VERBOSE, "; ");
            }

            av_log(NULL, AV_LOG_VERBOSE, "%"PRIu64" packets muxed (%"PRIu64" bytes); ",
                   ost->packets_written, ost->data_size);

            av_log(NULL, AV_LOG_VERBOSE, "\n");
        }

        av_log(NULL, AV_LOG_VERBOSE, "  Total: %"PRIu64" packets (%"PRIu64" bytes) muxed\n",
               total_packets, total_size);
    }
    if(video_size + data_size + audio_size + subtitle_size + extra_size == 0){
        av_log(NULL, AV_LOG_WARNING, "Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)\n");
    }
}

static void print_report(int is_last_report, int64_t timer_start, int64_t cur_time)
{
    char buf[1024];
    AVBPrint buf_script;
    OutputStream *ost;
    AVFormatContext *oc;
    int64_t total_size;
    AVCodecContext *enc;
    int frame_number, vid, i;
    double bitrate;
    int64_t pts = INT64_MIN;
    static int64_t last_time = -1;
    static int qp_histogram[52];
    int hours, mins, secs, us;

    if (!print_stats && !is_last_report && !progress_avio)
        return;

    if (!is_last_report) {
        if (last_time == -1) {
            last_time = cur_time;
            return;
        }
        if ((cur_time - last_time) < 500000)
            return;
        last_time = cur_time;
    }


    oc = output_files[0]->ctx;

    total_size = avio_size(oc->pb);
    if (total_size <= 0) // FIXME improve avio_size() so it works with non seekable output too
        total_size = avio_tell(oc->pb);

    buf[0] = '\0';
    vid = 0;
    av_bprint_init(&buf_script, 0, 1);
    for (i = 0; i < nb_output_streams; i++) {
        float q = -1;
        ost = output_streams[i];
        enc = ost->enc_ctx;
        if (!ost->stream_copy && enc->coded_frame)
            q = enc->coded_frame->quality / (float)FF_QP2LAMBDA;
        if (vid && enc->codec_type == AVMEDIA_TYPE_VIDEO) {
            snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "q=%2.1f ", q);
            av_bprintf(&buf_script, "stream_%d_%d_q=%.1f\n",
                       ost->file_index, ost->index, q);
        }
        if (!vid && enc->codec_type == AVMEDIA_TYPE_VIDEO) {
            float fps, t = (cur_time-timer_start) / 1000000.0;

            frame_number = ost->frame_number;
            fps = t > 1 ? frame_number / t : 0;
            snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "frame=%5d fps=%3.*f q=%3.1f ",
                     frame_number, fps < 9.95, fps, q);
            av_bprintf(&buf_script, "frame=%d\n", frame_number);
            av_bprintf(&buf_script, "fps=%.1f\n", fps);
            av_bprintf(&buf_script, "stream_%d_%d_q=%.1f\n",
                       ost->file_index, ost->index, q);
            if (is_last_report)
                snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "L");
            if (qp_hist) {
                int j;
                int qp = lrintf(q);
                if (qp >= 0 && qp < FF_ARRAY_ELEMS(qp_histogram))
                    qp_histogram[qp]++;
                for (j = 0; j < 32; j++)
                    snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "%X", (int)lrintf(log2(qp_histogram[j] + 1)));
            }
            if ((enc->flags&CODEC_FLAG_PSNR) && (enc->coded_frame || is_last_report)) {
                int j;
                double error, error_sum = 0;
                double scale, scale_sum = 0;
                double p;
                char type[3] = { 'Y','U','V' };
                snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "PSNR=");
                for (j = 0; j < 3; j++) {
                    if (is_last_report) {
                        error = enc->error[j];
                        scale = enc->width * enc->height * 255.0 * 255.0 * frame_number;
                    } else {
                        error = enc->coded_frame->error[j];
                        scale = enc->width * enc->height * 255.0 * 255.0;
                    }
                    if (j)
                        scale /= 4;
                    error_sum += error;
                    scale_sum += scale;
                    p = psnr(error / scale);
                    snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "%c:%2.2f ", type[j], p);
                    av_bprintf(&buf_script, "stream_%d_%d_psnr_%c=%2.2f\n",
                               ost->file_index, ost->index, type[j] | 32, p);
                }
                p = psnr(error_sum / scale_sum);
                snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "*:%2.2f ", psnr(error_sum / scale_sum));
                av_bprintf(&buf_script, "stream_%d_%d_psnr_all=%2.2f\n",
                           ost->file_index, ost->index, p);
            }
            vid = 1;
        }
        /* compute min output value */
        if (av_stream_get_end_pts(ost->st) != AV_NOPTS_VALUE)
            pts = FFMAX(pts, av_rescale_q(av_stream_get_end_pts(ost->st),
                                          ost->st->time_base, AV_TIME_BASE_Q));
    }

    secs = pts / AV_TIME_BASE;
    us = pts % AV_TIME_BASE;
    mins = secs / 60;
    secs %= 60;
    hours = mins / 60;
    mins %= 60;

    bitrate = pts && total_size >= 0 ? total_size * 8 / (pts / 1000.0) : -1;

    if (total_size < 0) snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
                                 "size=N/A time=");
    else                snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
                                 "size=%8.0fkB time=", total_size / 1024.0);
    snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
             "%02d:%02d:%02d.%02d ", hours, mins, secs,
             (100 * us) / AV_TIME_BASE);
    if (bitrate < 0) snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
                              "bitrate=N/A");
    else             snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
                              "bitrate=%6.1fkbits/s", bitrate);
    if (total_size < 0) av_bprintf(&buf_script, "total_size=N/A\n");
    else                av_bprintf(&buf_script, "total_size=%"PRId64"\n", total_size);
    av_bprintf(&buf_script, "out_time_ms=%"PRId64"\n", pts);
    av_bprintf(&buf_script, "out_time=%02d:%02d:%02d.%06d\n",
               hours, mins, secs, us);

    if (nb_frames_dup || nb_frames_drop)
        snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), " dup=%d drop=%d",
                nb_frames_dup, nb_frames_drop);
    av_bprintf(&buf_script, "dup_frames=%d\n", nb_frames_dup);
    av_bprintf(&buf_script, "drop_frames=%d\n", nb_frames_drop);

    if (print_stats || is_last_report) {
        if (print_stats==1 && AV_LOG_INFO > av_log_get_level()) {
            fprintf(stderr, "%s    \r", buf);
        } else
            av_log(NULL, AV_LOG_INFO, "%s    \r", buf);

    fflush(stderr);
    }

    if (progress_avio) {
        av_bprintf(&buf_script, "progress=%s\n",
                   is_last_report ? "end" : "continue");
        avio_write(progress_avio, buf_script.str,
                   FFMIN(buf_script.len, buf_script.size - 1));
        avio_flush(progress_avio);
        av_bprint_finalize(&buf_script, NULL);
        if (is_last_report) {
            avio_close(progress_avio);
            progress_avio = NULL;
        }
    }

    if (is_last_report)
        print_final_stats(total_size);
}

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

    for (i = 0; i < nb_output_streams; i++) {
        OutputStream   *ost = output_streams[i];
        AVCodecContext *enc = ost->enc_ctx;
        AVFormatContext *os = output_files[ost->file_index]->ctx;
        int stop_encoding = 0;

        if (!ost->encoding_needed)
            continue;

        if (enc->codec_type == AVMEDIA_TYPE_AUDIO && enc->frame_size <= 1)
            continue;
        if (enc->codec_type == AVMEDIA_TYPE_VIDEO && (os->oformat->flags & AVFMT_RAWPICTURE) && enc->codec->id == AV_CODEC_ID_RAWVIDEO)
            continue;

        for (;;) {
            int (*encode)(AVCodecContext*, AVPacket*, const AVFrame*, int*) = NULL;
            const char *desc;

            switch (enc->codec_type) {
            case AVMEDIA_TYPE_AUDIO:
                encode = avcodec_encode_audio2;
                desc   = "Audio";
                break;
            case AVMEDIA_TYPE_VIDEO:
                encode = avcodec_encode_video2;
                desc   = "Video";
                break;
            default:
                stop_encoding = 1;
            }

            if (encode) {
                AVPacket pkt;
                int pkt_size;
                int got_packet;
                av_init_packet(&pkt);
                pkt.data = NULL;
                pkt.size = 0;

                update_benchmark(NULL);
                ret = encode(enc, &pkt, NULL, &got_packet);
                update_benchmark("flush %s %d.%d", desc, ost->file_index, ost->index);
                if (ret < 0) {
                    av_log(NULL, AV_LOG_FATAL, "%s encoding failed\n", desc);
                    exit_program(1);
                }
                if (ost->logfile && enc->stats_out) {
                    fprintf(ost->logfile, "%s", enc->stats_out);
                }
                if (!got_packet) {
                    stop_encoding = 1;
                    break;
                }
                if (ost->finished & MUXER_FINISHED) {
                    av_free_packet(&pkt);
                    continue;
                }
                av_packet_rescale_ts(&pkt, enc->time_base, ost->st->time_base);
                pkt_size = pkt.size;
                write_frame(os, &pkt, ost);
                if (ost->enc_ctx->codec_type == AVMEDIA_TYPE_VIDEO && vstats_filename) {
                    do_video_stats(ost, pkt_size);
                }
            }

            if (stop_encoding)
                break;
        }
    }
}

/*
 * Check whether a packet from ist should be written into ost at this time
 */
static int check_output_constraints(InputStream *ist, OutputStream *ost)
{
    OutputFile *of = output_files[ost->file_index];
    int ist_index  = input_files[ist->file_index]->ist_index + ist->st->index;

    if (ost->source_index != ist_index)
        return 0;

    if (ost->finished)
        return 0;

    if (of->start_time != AV_NOPTS_VALUE && ist->pts < of->start_time)
        return 0;

    return 1;
}

static void do_streamcopy(InputStream *ist, OutputStream *ost, const AVPacket *pkt)
{
    OutputFile *of = output_files[ost->file_index];
    InputFile   *f = input_files [ist->file_index];
    int64_t start_time = (of->start_time == AV_NOPTS_VALUE) ? 0 : of->start_time;
    int64_t ost_tb_start_time = av_rescale_q(start_time, AV_TIME_BASE_Q, ost->st->time_base);
    int64_t ist_tb_start_time = av_rescale_q(start_time, AV_TIME_BASE_Q, ist->st->time_base);
    AVPicture pict;
    AVPacket opkt;

    av_init_packet(&opkt);

    if ((!ost->frame_number && !(pkt->flags & AV_PKT_FLAG_KEY)) &&
        !ost->copy_initial_nonkeyframes)
        return;

    if (pkt->pts == AV_NOPTS_VALUE) {
        if (!ost->frame_number && ist->pts < start_time &&
            !ost->copy_prior_start)
            return;
    } else {
        if (!ost->frame_number && pkt->pts < ist_tb_start_time &&
            !ost->copy_prior_start)
            return;
    }

    if (of->recording_time != INT64_MAX &&
        ist->pts >= of->recording_time + start_time) {
        close_output_stream(ost);
        return;
    }

    if (f->recording_time != INT64_MAX) {
        start_time = f->ctx->start_time;
        if (f->start_time != AV_NOPTS_VALUE)
            start_time += f->start_time;
        if (ist->pts >= f->recording_time + start_time) {
            close_output_stream(ost);
            return;
        }
    }

    /* force the input stream PTS */
    if (ost->enc_ctx->codec_type == AVMEDIA_TYPE_VIDEO)
        ost->sync_opts++;

    if (pkt->pts != AV_NOPTS_VALUE)
        opkt.pts = av_rescale_q(pkt->pts, ist->st->time_base, ost->st->time_base) - ost_tb_start_time;
    else
        opkt.pts = AV_NOPTS_VALUE;

    if (pkt->dts == AV_NOPTS_VALUE)
        opkt.dts = av_rescale_q(ist->dts, AV_TIME_BASE_Q, ost->st->time_base);
    else
        opkt.dts = av_rescale_q(pkt->dts, ist->st->time_base, ost->st->time_base);
    opkt.dts -= ost_tb_start_time;

    if (ost->st->codec->codec_type == AVMEDIA_TYPE_AUDIO && pkt->dts != AV_NOPTS_VALUE) {
        int duration = av_get_audio_frame_duration(ist->dec_ctx, pkt->size);
        if(!duration)
            duration = ist->dec_ctx->frame_size;
        opkt.dts = opkt.pts = av_rescale_delta(ist->st->time_base, pkt->dts,
                                               (AVRational){1, ist->dec_ctx->sample_rate}, duration, &ist->filter_in_rescale_delta_last,
                                               ost->st->time_base) - ost_tb_start_time;
    }

    opkt.duration = av_rescale_q(pkt->duration, ist->st->time_base, ost->st->time_base);
    opkt.flags    = pkt->flags;

    // FIXME remove the following 2 lines they shall be replaced by the bitstream filters
    if (  ost->enc_ctx->codec_id != AV_CODEC_ID_H264
       && ost->enc_ctx->codec_id != AV_CODEC_ID_MPEG1VIDEO
       && ost->enc_ctx->codec_id != AV_CODEC_ID_MPEG2VIDEO
       && ost->enc_ctx->codec_id != AV_CODEC_ID_VC1
       ) {
        if (av_parser_change(ost->parser, ost->st->codec,
                             &opkt.data, &opkt.size,
                             pkt->data, pkt->size,
                             pkt->flags & AV_PKT_FLAG_KEY)) {
            opkt.buf = av_buffer_create(opkt.data, opkt.size, av_buffer_default_free, NULL, 0);
            if (!opkt.buf)
                exit_program(1);
        }
    } else {
        opkt.data = pkt->data;
        opkt.size = pkt->size;
    }
    av_copy_packet_side_data(&opkt, pkt);

    if (ost->st->codec->codec_type == AVMEDIA_TYPE_VIDEO && (of->ctx->oformat->flags & AVFMT_RAWPICTURE)) {
        /* store AVPicture in AVPacket, as expected by the output format */
        avpicture_fill(&pict, opkt.data, ost->st->codec->pix_fmt, ost->st->codec->width, ost->st->codec->height);
        opkt.data = (uint8_t *)&pict;
        opkt.size = sizeof(AVPicture);
        opkt.flags |= AV_PKT_FLAG_KEY;
    }

    write_frame(of->ctx, &opkt, ost);
}

int guess_input_channel_layout(InputStream *ist)
{
    AVCodecContext *dec = ist->dec_ctx;

    if (!dec->channel_layout) {
        char layout_name[256];

        if (dec->channels > ist->guess_layout_max)
            return 0;
        dec->channel_layout = av_get_default_channel_layout(dec->channels);
        if (!dec->channel_layout)
            return 0;
        av_get_channel_layout_string(layout_name, sizeof(layout_name),
                                     dec->channels, dec->channel_layout);
        av_log(NULL, AV_LOG_WARNING, "Guessed Channel Layout for  Input Stream "
               "#%d.%d : %s\n", ist->file_index, ist->st->index, layout_name);
    }
    return 1;
}

static int decode_audio(InputStream *ist, AVPacket *pkt, int *got_output)
{
    AVFrame *decoded_frame, *f;
    AVCodecContext *avctx = ist->dec_ctx;
    int i, ret, err = 0, resample_changed;
    AVRational decoded_frame_tb;

    if (!ist->decoded_frame && !(ist->decoded_frame = av_frame_alloc()))
        return AVERROR(ENOMEM);
    if (!ist->filter_frame && !(ist->filter_frame = av_frame_alloc()))
        return AVERROR(ENOMEM);
    decoded_frame = ist->decoded_frame;

    update_benchmark(NULL);
    ret = avcodec_decode_audio4(avctx, decoded_frame, got_output, pkt);
    update_benchmark("decode_audio %d.%d", ist->file_index, ist->st->index);

    if (ret >= 0 && avctx->sample_rate <= 0) {
        av_log(avctx, AV_LOG_ERROR, "Sample rate %d invalid\n", avctx->sample_rate);
        ret = AVERROR_INVALIDDATA;
    }

    if (*got_output || ret<0 || pkt->size)
        decode_error_stat[ret<0] ++;

    if (!*got_output || ret < 0) {
        if (!pkt->size) {
            for (i = 0; i < ist->nb_filters; i++)
#if 1
                av_buffersrc_add_ref(ist->filters[i]->filter, NULL, 0);
#else
                av_buffersrc_add_frame(ist->filters[i]->filter, NULL);
#endif
        }
        return ret;
    }

    ist->samples_decoded += decoded_frame->nb_samples;
    ist->frames_decoded++;

#if 1
    /* increment next_dts to use for the case where the input stream does not
       have timestamps or there are multiple frames in the packet */
    ist->next_pts += ((int64_t)AV_TIME_BASE * decoded_frame->nb_samples) /
                     avctx->sample_rate;
    ist->next_dts += ((int64_t)AV_TIME_BASE * decoded_frame->nb_samples) /
                     avctx->sample_rate;
#endif

    resample_changed = ist->resample_sample_fmt     != decoded_frame->format         ||
                       ist->resample_channels       != avctx->channels               ||
                       ist->resample_channel_layout != decoded_frame->channel_layout ||
                       ist->resample_sample_rate    != decoded_frame->sample_rate;
    if (resample_changed) {
        char layout1[64], layout2[64];

        if (!guess_input_channel_layout(ist)) {
            av_log(NULL, AV_LOG_FATAL, "Unable to find default channel "
                   "layout for Input Stream #%d.%d\n", ist->file_index,
                   ist->st->index);
            exit_program(1);
        }
        decoded_frame->channel_layout = avctx->channel_layout;

        av_get_channel_layout_string(layout1, sizeof(layout1), ist->resample_channels,
                                     ist->resample_channel_layout);
        av_get_channel_layout_string(layout2, sizeof(layout2), avctx->channels,
                                     decoded_frame->channel_layout);

        av_log(NULL, AV_LOG_INFO,
               "Input stream #%d:%d frame changed from rate:%d fmt:%s ch:%d chl:%s to rate:%d fmt:%s ch:%d chl:%s\n",
               ist->file_index, ist->st->index,
               ist->resample_sample_rate,  av_get_sample_fmt_name(ist->resample_sample_fmt),
               ist->resample_channels, layout1,
               decoded_frame->sample_rate, av_get_sample_fmt_name(decoded_frame->format),
               avctx->channels, layout2);

        ist->resample_sample_fmt     = decoded_frame->format;
        ist->resample_sample_rate    = decoded_frame->sample_rate;
        ist->resample_channel_layout = decoded_frame->channel_layout;
        ist->resample_channels       = avctx->channels;

        for (i = 0; i < nb_filtergraphs; i++)
            if (ist_in_filtergraph(filtergraphs[i], ist)) {
                FilterGraph *fg = filtergraphs[i];
                if (configure_filtergraph(fg) < 0) {
                    av_log(NULL, AV_LOG_FATAL, "Error reinitializing filters!\n");
                    exit_program(1);
                }
            }
    }

    /* if the decoder provides a pts, use it instead of the last packet pts.
       the decoder could be delaying output by a packet or more. */
    if (decoded_frame->pts != AV_NOPTS_VALUE) {
        ist->dts = ist->next_dts = ist->pts = ist->next_pts = av_rescale_q(decoded_frame->pts, avctx->time_base, AV_TIME_BASE_Q);
        decoded_frame_tb   = avctx->time_base;
    } else if (decoded_frame->pkt_pts != AV_NOPTS_VALUE) {
        decoded_frame->pts = decoded_frame->pkt_pts;
        decoded_frame_tb   = ist->st->time_base;
    } else if (pkt->pts != AV_NOPTS_VALUE) {
        decoded_frame->pts = pkt->pts;
        decoded_frame_tb   = ist->st->time_base;
    }else {
        decoded_frame->pts = ist->dts;
        decoded_frame_tb   = AV_TIME_BASE_Q;
    }
    pkt->pts           = AV_NOPTS_VALUE;
    if (decoded_frame->pts != AV_NOPTS_VALUE)
        decoded_frame->pts = av_rescale_delta(decoded_frame_tb, decoded_frame->pts,
                                              (AVRational){1, avctx->sample_rate}, decoded_frame->nb_samples, &ist->filter_in_rescale_delta_last,
                                              (AVRational){1, avctx->sample_rate});
    for (i = 0; i < ist->nb_filters; i++) {
        if (i < ist->nb_filters - 1) {
            f = ist->filter_frame;
            err = av_frame_ref(f, decoded_frame);
            if (err < 0)
                break;
        } else
            f = decoded_frame;
        err = av_buffersrc_add_frame_flags(ist->filters[i]->filter, f,
                                     AV_BUFFERSRC_FLAG_PUSH);
        if (err == AVERROR_EOF)
            err = 0; /* ignore */
        if (err < 0)
            break;
    }
    decoded_frame->pts = AV_NOPTS_VALUE;

    av_frame_unref(ist->filter_frame);
    av_frame_unref(decoded_frame);
    return err < 0 ? err : ret;
}

static int decode_video(InputStream *ist, AVPacket *pkt, int *got_output)
{
    AVFrame *decoded_frame, *f;
    int i, ret = 0, err = 0, resample_changed;
    int64_t best_effort_timestamp;
    AVRational *frame_sample_aspect;

    if (!ist->decoded_frame && !(ist->decoded_frame = av_frame_alloc()))
        return AVERROR(ENOMEM);
    if (!ist->filter_frame && !(ist->filter_frame = av_frame_alloc()))
        return AVERROR(ENOMEM);
    decoded_frame = ist->decoded_frame;
    pkt->dts  = av_rescale_q(ist->dts, AV_TIME_BASE_Q, ist->st->time_base);

    update_benchmark(NULL);
    ret = avcodec_decode_video2(ist->dec_ctx,
                                decoded_frame, got_output, pkt);
    update_benchmark("decode_video %d.%d", ist->file_index, ist->st->index);

    // The following line may be required in some cases where there is no parser
    // or the parser does not has_b_frames correctly
    if (ist->st->codec->has_b_frames < ist->dec_ctx->has_b_frames) {
        if (ist->dec_ctx->codec_id == AV_CODEC_ID_H264) {
            ist->st->codec->has_b_frames = ist->dec_ctx->has_b_frames;
        } else
            av_log_ask_for_sample(
                ist->dec_ctx,
                "has_b_frames is larger in decoder than demuxer %d > %d ",
                ist->dec_ctx->has_b_frames,
                ist->st->codec->has_b_frames
            );
    }

    if (*got_output || ret<0 || pkt->size)
        decode_error_stat[ret<0] ++;

    if (!*got_output || ret < 0) {
        if (!pkt->size) {
            for (i = 0; i < ist->nb_filters; i++)
#if 1
                av_buffersrc_add_ref(ist->filters[i]->filter, NULL, 0);
#else
                av_buffersrc_add_frame(ist->filters[i]->filter, NULL);
#endif
        }
        return ret;
    }

    if(ist->top_field_first>=0)
        decoded_frame->top_field_first = ist->top_field_first;

    ist->frames_decoded++;

    if (ist->hwaccel_retrieve_data && decoded_frame->format == ist->hwaccel_pix_fmt) {
        err = ist->hwaccel_retrieve_data(ist->dec_ctx, decoded_frame);
        if (err < 0)
            goto fail;
    }
    ist->hwaccel_retrieved_pix_fmt = decoded_frame->format;

    best_effort_timestamp= av_frame_get_best_effort_timestamp(decoded_frame);
    if(best_effort_timestamp != AV_NOPTS_VALUE)
        ist->next_pts = ist->pts = av_rescale_q(decoded_frame->pts = best_effort_timestamp, ist->st->time_base, AV_TIME_BASE_Q);

    if (debug_ts) {
        av_log(NULL, AV_LOG_INFO, "decoder -> ist_index:%d type:video "
               "frame_pts:%s frame_pts_time:%s best_effort_ts:%"PRId64" best_effort_ts_time:%s keyframe:%d frame_type:%d time_base:%d/%d\n",
               ist->st->index, av_ts2str(decoded_frame->pts),
               av_ts2timestr(decoded_frame->pts, &ist->st->time_base),
               best_effort_timestamp,
               av_ts2timestr(best_effort_timestamp, &ist->st->time_base),
               decoded_frame->key_frame, decoded_frame->pict_type,
               ist->st->time_base.num, ist->st->time_base.den);
    }

    pkt->size = 0;

    if (ist->st->sample_aspect_ratio.num)
        decoded_frame->sample_aspect_ratio = ist->st->sample_aspect_ratio;

    resample_changed = ist->resample_width   != decoded_frame->width  ||
                       ist->resample_height  != decoded_frame->height ||
                       ist->resample_pix_fmt != decoded_frame->format;
    if (resample_changed) {
        av_log(NULL, AV_LOG_INFO,
               "Input stream #%d:%d frame changed from size:%dx%d fmt:%s to size:%dx%d fmt:%s\n",
               ist->file_index, ist->st->index,
               ist->resample_width,  ist->resample_height,  av_get_pix_fmt_name(ist->resample_pix_fmt),
               decoded_frame->width, decoded_frame->height, av_get_pix_fmt_name(decoded_frame->format));

        ist->resample_width   = decoded_frame->width;
        ist->resample_height  = decoded_frame->height;
        ist->resample_pix_fmt = decoded_frame->format;

        for (i = 0; i < nb_filtergraphs; i++) {
            if (ist_in_filtergraph(filtergraphs[i], ist) && ist->reinit_filters &&
                configure_filtergraph(filtergraphs[i]) < 0) {
                av_log(NULL, AV_LOG_FATAL, "Error reinitializing filters!\n");
                exit_program(1);
            }
        }
    }

    frame_sample_aspect= av_opt_ptr(avcodec_get_frame_class(), decoded_frame, "sample_aspect_ratio");
    for (i = 0; i < ist->nb_filters; i++) {
        if (!frame_sample_aspect->num)
            *frame_sample_aspect = ist->st->sample_aspect_ratio;

        if (i < ist->nb_filters - 1) {
            f = ist->filter_frame;
            err = av_frame_ref(f, decoded_frame);
            if (err < 0)
                break;
        } else
            f = decoded_frame;
        ret = av_buffersrc_add_frame_flags(ist->filters[i]->filter, f, AV_BUFFERSRC_FLAG_PUSH);
        if (ret == AVERROR_EOF) {
            ret = 0; /* ignore */
        } else if (ret < 0) {
            av_log(NULL, AV_LOG_FATAL,
                   "Failed to inject frame into filter network: %s\n", av_err2str(ret));
            exit_program(1);
        }
    }

fail:
    av_frame_unref(ist->filter_frame);
    av_frame_unref(decoded_frame);