ffmpeg.c

            if (ret < 0) {
                av_log(NULL, AV_LOG_FATAL, "Audio encoding failed\n");
                exit_program(1);
            }
            audio_size += ret;
            pkt.stream_index= ost->index;
            pkt.data= audio_out;
            pkt.size= ret;
            if(enc->coded_frame && enc->coded_frame->pts != AV_NOPTS_VALUE)
                pkt.pts= av_rescale_q(enc->coded_frame->pts, enc->time_base, ost->st->time_base);
            pkt.flags |= AV_PKT_FLAG_KEY;
            write_frame(s, &pkt, enc, ost->bitstream_filters);

            ost->sync_opts += enc->frame_size;
        }
    } else {
        AVPacket pkt;
        av_init_packet(&pkt);

        ost->sync_opts += size_out / (osize * enc->channels);

        /* output a pcm frame */
        /* determine the size of the coded buffer */
        size_out /= osize;
        if (coded_bps)
            size_out = size_out*coded_bps/8;

        if(size_out > audio_out_size){
            av_log(NULL, AV_LOG_FATAL, "Internal error, buffer size too small\n");
            exit_program(1);
        }

        //FIXME pass ost->sync_opts as AVFrame.pts in avcodec_encode_audio()
        ret = avcodec_encode_audio(enc, audio_out, size_out,
                                   (short *)buftmp);
        if (ret < 0) {
            av_log(NULL, AV_LOG_FATAL, "Audio encoding failed\n");
            exit_program(1);
        }
        audio_size += ret;
        pkt.stream_index= ost->index;
        pkt.data= audio_out;
        pkt.size= ret;
        if(enc->coded_frame && enc->coded_frame->pts != AV_NOPTS_VALUE)
            pkt.pts= av_rescale_q(enc->coded_frame->pts, enc->time_base, ost->st->time_base);
        pkt.flags |= AV_PKT_FLAG_KEY;
        write_frame(s, &pkt, enc, ost->bitstream_filters);
    }
}

static void pre_process_video_frame(InputStream *ist, AVPicture *picture, void **bufp)
{
    AVCodecContext *dec;
    AVPicture *picture2;
    AVPicture picture_tmp;
    uint8_t *buf = 0;

    dec = ist->st->codec;

    /* deinterlace : must be done before any resize */
    if (do_deinterlace) {
        int size;

        /* create temporary picture */
        size = avpicture_get_size(dec->pix_fmt, dec->width, dec->height);
        buf = av_malloc(size);
        if (!buf)
            return;

        picture2 = &picture_tmp;
        avpicture_fill(picture2, buf, dec->pix_fmt, dec->width, dec->height);

        if(avpicture_deinterlace(picture2, picture,
                                 dec->pix_fmt, dec->width, dec->height) < 0) {
            /* if error, do not deinterlace */
            av_log(NULL, AV_LOG_WARNING, "Deinterlacing failed\n");
            av_free(buf);
            buf = NULL;
            picture2 = picture;
        }
    } else {
        picture2 = picture;
    }

    if (picture != picture2)
        *picture = *picture2;
    *bufp = buf;
}

static void do_subtitle_out(AVFormatContext *s,
                            OutputStream *ost,
                            InputStream *ist,
                            AVSubtitle *sub,
                            int64_t pts)
{
    static uint8_t *subtitle_out = NULL;
    int subtitle_out_max_size = 1024 * 1024;
    int subtitle_out_size, nb, i;
    AVCodecContext *enc;
    AVPacket pkt;

    if (pts == AV_NOPTS_VALUE) {
        av_log(NULL, AV_LOG_ERROR, "Subtitle packets must have a pts\n");
        if (exit_on_error)
            exit_program(1);
        return;
    }

    enc = ost->st->codec;

    if (!subtitle_out) {
        subtitle_out = av_malloc(subtitle_out_max_size);
    }

    /* Note: DVB subtitle need one packet to draw them and one other
       packet to clear them */
    /* XXX: signal it in the codec context ? */
    if (enc->codec_id == CODEC_ID_DVB_SUBTITLE)
        nb = 2;
    else
        nb = 1;

    for(i = 0; i < nb; i++) {
        sub->pts = av_rescale_q(pts, ist->st->time_base, AV_TIME_BASE_Q);
        // start_display_time is required to be 0
        sub->pts              += av_rescale_q(sub->start_display_time, (AVRational){1, 1000}, AV_TIME_BASE_Q);
        sub->end_display_time -= sub->start_display_time;
        sub->start_display_time = 0;
        subtitle_out_size = avcodec_encode_subtitle(enc, subtitle_out,
                                                    subtitle_out_max_size, sub);
        if (subtitle_out_size < 0) {
            av_log(NULL, AV_LOG_FATAL, "Subtitle encoding failed\n");
            exit_program(1);
        }

        av_init_packet(&pkt);
        pkt.stream_index = ost->index;
        pkt.data = subtitle_out;
        pkt.size = subtitle_out_size;
        pkt.pts = av_rescale_q(sub->pts, AV_TIME_BASE_Q, ost->st->time_base);
        if (enc->codec_id == CODEC_ID_DVB_SUBTITLE) {
            /* XXX: the pts correction is handled here. Maybe handling
               it in the codec would be better */
            if (i == 0)
                pkt.pts += 90 * sub->start_display_time;
            else
                pkt.pts += 90 * sub->end_display_time;
        }
        write_frame(s, &pkt, ost->st->codec, ost->bitstream_filters);
    }
}

static int bit_buffer_size= 1024*256;
static uint8_t *bit_buffer= NULL;

static void do_video_resample(OutputStream *ost,
                              InputStream *ist,
                              AVFrame *in_picture,
                              AVFrame **out_picture)
{
#if CONFIG_AVFILTER
    *out_picture = in_picture;
#else
    AVCodecContext *dec = ist->st->codec;
    AVCodecContext *enc = ost->st->codec;
    int resample_changed = ost->resample_width   != dec->width  ||
                           ost->resample_height  != dec->height ||
                           ost->resample_pix_fmt != dec->pix_fmt;

    *out_picture = in_picture;
    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,
               ost->resample_width, ost->resample_height, av_get_pix_fmt_name(ost->resample_pix_fmt),
               dec->width         , dec->height         , av_get_pix_fmt_name(dec->pix_fmt));
        ost->resample_width   = dec->width;
        ost->resample_height  = dec->height;
        ost->resample_pix_fmt = dec->pix_fmt;
    }

    ost->video_resample = dec->width   != enc->width  ||
                          dec->height  != enc->height ||
                          dec->pix_fmt != enc->pix_fmt;

    if (ost->video_resample) {
        *out_picture = &ost->resample_frame;
        if (!ost->img_resample_ctx || resample_changed) {
            /* initialize the destination picture */
            if (!ost->resample_frame.data[0]) {
                avcodec_get_frame_defaults(&ost->resample_frame);
                if (avpicture_alloc((AVPicture *)&ost->resample_frame, enc->pix_fmt,
                                    enc->width, enc->height)) {
                    av_log(NULL, AV_LOG_FATAL, "Cannot allocate temp picture, check pix fmt\n");
                    exit_program(1);
                }
            }
            /* initialize a new scaler context */
            sws_freeContext(ost->img_resample_ctx);
            ost->img_resample_ctx = sws_getContext(dec->width, dec->height, dec->pix_fmt,
                                                   enc->width, enc->height, enc->pix_fmt,
                                                   ost->sws_flags, NULL, NULL, NULL);
            if (ost->img_resample_ctx == NULL) {
                av_log(NULL, AV_LOG_FATAL, "Cannot get resampling context\n");
                exit_program(1);
            }
        }
        sws_scale(ost->img_resample_ctx, in_picture->data, in_picture->linesize,
              0, ost->resample_height, (*out_picture)->data, (*out_picture)->linesize);
    }
#endif
}


static void do_video_out(AVFormatContext *s,
                         OutputStream *ost,
                         InputStream *ist,
                         AVFrame *in_picture,
                         int *frame_size, float quality)
{
    int nb_frames, i, ret, format_video_sync;
    AVFrame *final_picture;
    AVCodecContext *enc;
    double sync_ipts;
    double duration = 0;

    enc = ost->st->codec;

    if (ist->st->start_time != AV_NOPTS_VALUE && ist->st->first_dts != AV_NOPTS_VALUE) {
        duration = FFMAX(av_q2d(ist->st->time_base), av_q2d(ist->st->codec->time_base));
        if(ist->st->avg_frame_rate.num)
            duration= FFMAX(duration, 1/av_q2d(ist->st->avg_frame_rate));

        duration /= av_q2d(enc->time_base);
    }

    sync_ipts = get_sync_ipts(ost) / av_q2d(enc->time_base);

    /* by default, we output a single frame */
    nb_frames = 1;

    *frame_size = 0;

    format_video_sync = video_sync_method;
    if (format_video_sync < 0)
        format_video_sync = (s->oformat->flags & AVFMT_VARIABLE_FPS) ? 2 : 1;

    if (format_video_sync) {
        double vdelta = sync_ipts - ost->sync_opts + duration;
        //FIXME set to 0.5 after we fix some dts/pts bugs like in avidec.c
        if (vdelta < -1.1)
            nb_frames = 0;
        else if (format_video_sync == 2) {
            if(vdelta<=-0.6){
                nb_frames=0;
            }else if(vdelta>0.6)
                ost->sync_opts= lrintf(sync_ipts);
        }else if (vdelta > 1.1)
            nb_frames = lrintf(vdelta);
//fprintf(stderr, "vdelta:%f, ost->sync_opts:%"PRId64", ost->sync_ipts:%f nb_frames:%d\n", vdelta, ost->sync_opts, get_sync_ipts(ost), nb_frames);
        if (nb_frames == 0){
            ++nb_frames_drop;
            av_log(NULL, AV_LOG_VERBOSE, "*** drop!\n");
        }else if (nb_frames > 1) {
            nb_frames_dup += nb_frames - 1;
            av_log(NULL, AV_LOG_VERBOSE, "*** %d dup!\n", nb_frames-1);
        }
    }else
        ost->sync_opts= lrintf(sync_ipts);

    nb_frames = FFMIN(nb_frames, ost->max_frames - ost->frame_number);
    if (nb_frames <= 0)
        return;

    do_video_resample(ost, ist, in_picture, &final_picture);

    /* duplicates frame if needed */
    for(i=0;i<nb_frames;i++) {
        AVPacket pkt;
        av_init_packet(&pkt);
        pkt.stream_index= ost->index;

        if (s->oformat->flags & AVFMT_RAWPICTURE) {
            /* raw pictures are written as AVPicture structure to
               avoid any copies. We support temporarily the older
               method. */
            enc->coded_frame->interlaced_frame = in_picture->interlaced_frame;
            enc->coded_frame->top_field_first  = in_picture->top_field_first;
            pkt.data= (uint8_t *)final_picture;
            pkt.size=  sizeof(AVPicture);
            pkt.pts= av_rescale_q(ost->sync_opts, enc->time_base, ost->st->time_base);
            pkt.flags |= AV_PKT_FLAG_KEY;

            write_frame(s, &pkt, ost->st->codec, ost->bitstream_filters);
        } else {
            AVFrame big_picture;

            big_picture= *final_picture;
            /* better than nothing: use input picture interlaced
               settings */
            big_picture.interlaced_frame = in_picture->interlaced_frame;
            if (ost->st->codec->flags & (CODEC_FLAG_INTERLACED_DCT|CODEC_FLAG_INTERLACED_ME)) {
                if (ost->top_field_first == -1)
                    big_picture.top_field_first = in_picture->top_field_first;
                else
                    big_picture.top_field_first = !!ost->top_field_first;
            }

            /* handles same_quant here. This is not correct because it may
               not be a global option */
            big_picture.quality = quality;
            if (!enc->me_threshold)
                big_picture.pict_type = 0;
//            big_picture.pts = AV_NOPTS_VALUE;
            big_picture.pts= ost->sync_opts;
//            big_picture.pts= av_rescale(ost->sync_opts, AV_TIME_BASE*(int64_t)enc->time_base.num, enc->time_base.den);
//av_log(NULL, AV_LOG_DEBUG, "%"PRId64" -> encoder\n", ost->sync_opts);
            if (ost->forced_kf_index < ost->forced_kf_count &&
                big_picture.pts >= ost->forced_kf_pts[ost->forced_kf_index]) {
                big_picture.pict_type = AV_PICTURE_TYPE_I;
                ost->forced_kf_index++;
            }
            ret = avcodec_encode_video(enc,
                                       bit_buffer, bit_buffer_size,
                                       &big_picture);
            if (ret < 0) {
                av_log(NULL, AV_LOG_FATAL, "Video encoding failed\n");
                exit_program(1);
            }

            if(ret>0){
                pkt.data= bit_buffer;
                pkt.size= ret;
                if(enc->coded_frame->pts != AV_NOPTS_VALUE)
                    pkt.pts= av_rescale_q(enc->coded_frame->pts, enc->time_base, ost->st->time_base);
/*av_log(NULL, AV_LOG_DEBUG, "encoder -> %"PRId64"/%"PRId64"\n",
   pkt.pts != AV_NOPTS_VALUE ? av_rescale(pkt.pts, enc->time_base.den, AV_TIME_BASE*(int64_t)enc->time_base.num) : -1,
   pkt.dts != AV_NOPTS_VALUE ? av_rescale(pkt.dts, enc->time_base.den, AV_TIME_BASE*(int64_t)enc->time_base.num) : -1);*/

                if(enc->coded_frame->key_frame)
                    pkt.flags |= AV_PKT_FLAG_KEY;
                write_frame(s, &pkt, ost->st->codec, ost->bitstream_filters);
                *frame_size = ret;
                video_size += ret;
                //fprintf(stderr,"\nFrame: %3d size: %5d type: %d",
                //        enc->frame_number-1, ret, enc->pict_type);
                /* if two pass, output log */
                if (ost->logfile && enc->stats_out) {
                    fprintf(ost->logfile, "%s", enc->stats_out);
                }
            }
        }
        ost->sync_opts++;
        ost->frame_number++;
    }
}

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

static void do_video_stats(AVFormatContext *os, 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->st->codec;
    if (enc->codec_type == AVMEDIA_TYPE_VIDEO) {
        frame_number = ost->frame_number;
        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 = ost->sync_opts * av_q2d(enc->time_base);
        if (ti1 < 0.01)
            ti1 = 0.01;

        bitrate = (frame_size * 8) / av_q2d(enc->time_base) / 1000.0;
        avg_bitrate = (double)(video_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)video_size / 1024, ti1, bitrate, avg_bitrate);
        fprintf(vstats_file, "type= %c\n", av_get_picture_type_char(enc->coded_frame->pict_type));
    }
}

static void print_report(OutputFile *output_files,
                         OutputStream *ost_table, int nb_ostreams,
                         int is_last_report, int64_t timer_start, int64_t cur_time)
{
    char buf[1024];
    OutputStream *ost;
    AVFormatContext *oc;
    int64_t total_size;
    AVCodecContext *enc;
    int frame_number, vid, i;
    double bitrate;
    int64_t pts = INT64_MAX;
    static int64_t last_time = -1;
    static int qp_histogram[52];
    int hours, mins, secs, us;

    if (!print_stats && !is_last_report)
        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;
    for(i=0;i<nb_ostreams;i++) {
        float q = -1;
        ost = &ost_table[i];
        enc = ost->st->codec;
        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);
        }
        if (!vid && enc->codec_type == AVMEDIA_TYPE_VIDEO) {
            float t = (cur_time-timer_start) / 1000000.0;

            frame_number = ost->frame_number;
            snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "frame=%5d fps=%3d q=%3.1f ",
                     frame_number, (t>1)?(int)(frame_number/t+0.5) : 0, 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(log(qp_histogram[j]+1)/log(2)));
            }
            if (enc->flags&CODEC_FLAG_PSNR){
                int j;
                double error, error_sum=0;
                double scale, scale_sum=0;
                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;
                    snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "%c:%2.2f ", type[j], psnr(error/scale));
                }
                snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), "*:%2.2f ", psnr(error_sum/scale_sum));
            }
            vid = 1;
        }
        /* compute min output value */
        pts = FFMIN(pts, av_rescale_q(ost->st->pts.val,
                                      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 * 8 / (pts / 1000.0) : 0;

    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);
    snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
             "bitrate=%6.1fkbits/s", bitrate);

    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_log(NULL, AV_LOG_INFO, "%s    \r", buf);

    fflush(stderr);

    if (is_last_report) {
        int64_t raw= audio_size + video_size + extra_size;
        av_log(NULL, AV_LOG_INFO, "\n");
        av_log(NULL, AV_LOG_INFO, "video:%1.0fkB audio:%1.0fkB global headers:%1.0fkB muxing overhead %f%%\n",
               video_size/1024.0,
               audio_size/1024.0,
               extra_size/1024.0,
               100.0*(total_size - raw)/raw
        );
    }
}

static void generate_silence(uint8_t *buf, enum AVSampleFormat sample_fmt, size_t size)
{
    int fill_char = 0x00;
    if (sample_fmt == AV_SAMPLE_FMT_U8)
        fill_char = 0x80;
    memset(buf, fill_char, size);
}

static void flush_encoders(OutputStream *ost_table, int nb_ostreams)
{
    int i, ret;

    for (i = 0; i < nb_ostreams; i++) {
        OutputStream   *ost = &ost_table[i];
        AVCodecContext *enc = ost->st->codec;
        AVFormatContext *os = output_files[ost->file_index].ctx;

        if (!ost->encoding_needed)
            continue;

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

        for(;;) {
            AVPacket pkt;
            int fifo_bytes;
            av_init_packet(&pkt);
            pkt.stream_index= ost->index;

            switch (ost->st->codec->codec_type) {
            case AVMEDIA_TYPE_AUDIO:
                fifo_bytes = av_fifo_size(ost->fifo);
                ret = 0;
                /* encode any samples remaining in fifo */
                if (fifo_bytes > 0) {
                    int osize = av_get_bytes_per_sample(enc->sample_fmt);
                    int fs_tmp = enc->frame_size;

                    av_fifo_generic_read(ost->fifo, audio_buf, fifo_bytes, NULL);
                    if (enc->codec->capabilities & CODEC_CAP_SMALL_LAST_FRAME) {
                        enc->frame_size = fifo_bytes / (osize * enc->channels);
                    } else { /* pad */
                        int frame_bytes = enc->frame_size*osize*enc->channels;
                        if (allocated_audio_buf_size < frame_bytes)
                            exit_program(1);
                        generate_silence(audio_buf+fifo_bytes, enc->sample_fmt, frame_bytes - fifo_bytes);
                    }

                    ret = avcodec_encode_audio(enc, bit_buffer, bit_buffer_size, (short *)audio_buf);
                    pkt.duration = av_rescale((int64_t)enc->frame_size*ost->st->time_base.den,
                                              ost->st->time_base.num, enc->sample_rate);
                    enc->frame_size = fs_tmp;
                }
                if (ret <= 0) {
                    ret = avcodec_encode_audio(enc, bit_buffer, bit_buffer_size, NULL);
                }
                if (ret < 0) {
                    av_log(NULL, AV_LOG_FATAL, "Audio encoding failed\n");
                    exit_program(1);
                }
                audio_size += ret;
                pkt.flags |= AV_PKT_FLAG_KEY;
                break;
            case AVMEDIA_TYPE_VIDEO:
                ret = avcodec_encode_video(enc, bit_buffer, bit_buffer_size, NULL);
                if (ret < 0) {
                    av_log(NULL, AV_LOG_FATAL, "Video encoding failed\n");
                    exit_program(1);
                }
                video_size += ret;
                if(enc->coded_frame && enc->coded_frame->key_frame)
                    pkt.flags |= AV_PKT_FLAG_KEY;
                if (ost->logfile && enc->stats_out) {
                    fprintf(ost->logfile, "%s", enc->stats_out);
                }
                break;
            default:
                ret=-1;
            }

            if (ret <= 0)
                break;
            pkt.data = bit_buffer;
            pkt.size = ret;
            if (enc->coded_frame && enc->coded_frame->pts != AV_NOPTS_VALUE)
                pkt.pts= av_rescale_q(enc->coded_frame->pts, enc->time_base, ost->st->time_base);
            write_frame(os, &pkt, ost->st->codec, ost->bitstream_filters);
        }
    }
}

/* pkt = NULL means EOF (needed to flush decoder buffers) */
static int output_packet(InputStream *ist, int ist_index,
                         OutputStream *ost_table, int nb_ostreams,
                         const AVPacket *pkt)
{
    AVFormatContext *os;
    OutputStream *ost;
    int ret = 0, i;
    int got_output;
    void *buffer_to_free = NULL;
    static unsigned int samples_size= 0;
    AVSubtitle subtitle, *subtitle_to_free;
    int64_t pkt_pts = AV_NOPTS_VALUE;
#if CONFIG_AVFILTER
    int frame_available;
#endif
    float quality = 0;

    AVPacket avpkt;
    int bps = av_get_bytes_per_sample(ist->st->codec->sample_fmt);

    if(ist->next_pts == AV_NOPTS_VALUE)
        ist->next_pts= ist->pts;

    if (pkt == NULL) {
        /* EOF handling */
        av_init_packet(&avpkt);
        avpkt.data = NULL;
        avpkt.size = 0;
        goto handle_eof;
    } else {
        avpkt = *pkt;
    }

    if(pkt->dts != AV_NOPTS_VALUE)
        ist->next_pts = ist->pts = av_rescale_q(pkt->dts, ist->st->time_base, AV_TIME_BASE_Q);
    if(pkt->pts != AV_NOPTS_VALUE)
        pkt_pts = av_rescale_q(pkt->pts, ist->st->time_base, AV_TIME_BASE_Q);

    //while we have more to decode or while the decoder did output something on EOF
    while (avpkt.size > 0 || (!pkt && got_output)) {
        uint8_t *data_buf, *decoded_data_buf;
        int data_size, decoded_data_size;
        AVFrame *decoded_frame, *filtered_frame;
    handle_eof:
        ist->pts= ist->next_pts;

        if(avpkt.size && avpkt.size != pkt->size)
            av_log(NULL, ist->showed_multi_packet_warning ? AV_LOG_VERBOSE : AV_LOG_WARNING,
                   "Multiple frames in a packet from stream %d\n", pkt->stream_index);
            ist->showed_multi_packet_warning=1;

        /* decode the packet if needed */
        decoded_frame    = filtered_frame = NULL;
        decoded_data_buf = NULL; /* fail safe */
        decoded_data_size= 0;
        data_buf  = avpkt.data;
        data_size = avpkt.size;
        subtitle_to_free = NULL;
        if (ist->decoding_needed) {
            switch(ist->st->codec->codec_type) {
            case AVMEDIA_TYPE_AUDIO:{
                if(pkt && samples_size < FFMAX(pkt->size * bps, AVCODEC_MAX_AUDIO_FRAME_SIZE)) {
                    samples_size = FFMAX(pkt->size * bps, AVCODEC_MAX_AUDIO_FRAME_SIZE);
                    av_free(samples);
                    samples= av_malloc(samples_size);
                }
                decoded_data_size= samples_size;
                    /* XXX: could avoid copy if PCM 16 bits with same
                       endianness as CPU */
                ret = avcodec_decode_audio3(ist->st->codec, samples, &decoded_data_size,
                                            &avpkt);
                if (ret < 0)
                    return ret;
                avpkt.data += ret;
                avpkt.size -= ret;
                data_size   = ret;
                got_output  = decoded_data_size > 0;
                /* Some bug in mpeg audio decoder gives */
                /* decoded_data_size < 0, it seems they are overflows */
                if (!got_output) {
                    /* no audio frame */
                    continue;
                }
                decoded_data_buf = (uint8_t *)samples;
                ist->next_pts += ((int64_t)AV_TIME_BASE/bps * decoded_data_size) /
                    (ist->st->codec->sample_rate * ist->st->codec->channels);
                break;}
            case AVMEDIA_TYPE_VIDEO:
                    if (!(decoded_frame = avcodec_alloc_frame()))
                        return AVERROR(ENOMEM);
                    avpkt.pts = pkt_pts;
                    avpkt.dts = ist->pts;
                    pkt_pts = AV_NOPTS_VALUE;

                    ret = avcodec_decode_video2(ist->st->codec,
                                                decoded_frame, &got_output, &avpkt);
                    quality = same_quant ? decoded_frame->quality : 0;
                    if (ret < 0)
                        goto fail;
                    if (!got_output) {
                        /* no picture yet */
                        av_freep(&decoded_frame);
                        goto discard_packet;
                    }
                    ist->next_pts = ist->pts = decoded_frame->best_effort_timestamp;
                    if (ist->st->codec->time_base.num != 0) {
                        int ticks= ist->st->parser ? ist->st->parser->repeat_pict+1 : ist->st->codec->ticks_per_frame;
                        ist->next_pts += ((int64_t)AV_TIME_BASE *
                                          ist->st->codec->time_base.num * ticks) /
                            ist->st->codec->time_base.den;
                    }
                    avpkt.size = 0;
                    buffer_to_free = NULL;
                    pre_process_video_frame(ist, (AVPicture *)decoded_frame, &buffer_to_free);
                    break;
            case AVMEDIA_TYPE_SUBTITLE:
                ret = avcodec_decode_subtitle2(ist->st->codec,
                                               &subtitle, &got_output, &avpkt);
                if (ret < 0)
                    return ret;
                if (!got_output) {
                    goto discard_packet;
                }
                subtitle_to_free = &subtitle;
                avpkt.size = 0;
                break;
            default:
                return -1;
            }
        } else {
            switch(ist->st->codec->codec_type) {
            case AVMEDIA_TYPE_AUDIO:
                ist->next_pts += ((int64_t)AV_TIME_BASE * ist->st->codec->frame_size) /
                    ist->st->codec->sample_rate;
                break;
            case AVMEDIA_TYPE_VIDEO:
                if (ist->st->codec->time_base.num != 0) {
                    int ticks= ist->st->parser ? ist->st->parser->repeat_pict+1 : ist->st->codec->ticks_per_frame;
                    ist->next_pts += ((int64_t)AV_TIME_BASE *
                                      ist->st->codec->time_base.num * ticks) /
                        ist->st->codec->time_base.den;
                }
                break;
            }
            avpkt.size = 0;
        }

#if CONFIG_AVFILTER
        if(ist->st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
        for(i=0;i<nb_ostreams;i++) {
            OutputFile *of = &output_files[ost_table[i].file_index];
            if (of->start_time == 0 || ist->pts >= of->start_time) {
                ost = &ost_table[i];
                if (ost->input_video_filter && ost->source_index == ist_index) {
                    if (!decoded_frame->sample_aspect_ratio.num)
                        decoded_frame->sample_aspect_ratio = ist->st->sample_aspect_ratio;
                    decoded_frame->pts = ist->pts;

                    av_vsrc_buffer_add_frame(ost->input_video_filter, decoded_frame, AV_VSRC_BUF_FLAG_OVERWRITE);
                }
            }
        }
#endif

        // preprocess audio (volume)
        if (ist->st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
            if (audio_volume != 256) {
                switch (ist->st->codec->sample_fmt) {
                case AV_SAMPLE_FMT_U8:
                {
                    uint8_t *volp = samples;
                    for (i = 0; i < (decoded_data_size / sizeof(*volp)); i++) {
                        int v = (((*volp - 128) * audio_volume + 128) >> 8) + 128;
                        *volp++ = av_clip_uint8(v);
                    }
                    break;
                }
                case AV_SAMPLE_FMT_S16:
                {
                    int16_t *volp = samples;
                    for (i = 0; i < (decoded_data_size / sizeof(*volp)); i++) {
                        int v = ((*volp) * audio_volume + 128) >> 8;
                        *volp++ = av_clip_int16(v);
                    }
                    break;
                }
                case AV_SAMPLE_FMT_S32:
                {
                    int32_t *volp = samples;
                    for (i = 0; i < (decoded_data_size / sizeof(*volp)); i++) {
                        int64_t v = (((int64_t)*volp * audio_volume + 128) >> 8);
                        *volp++ = av_clipl_int32(v);
                    }
                    break;
                }
                case AV_SAMPLE_FMT_FLT:
                {
                    float *volp = samples;
                    float scale = audio_volume / 256.f;
                    for (i = 0; i < (decoded_data_size / sizeof(*volp)); i++) {
                        *volp++ *= scale;
                    }
                    break;
                }
                case AV_SAMPLE_FMT_DBL:
                {
                    double *volp = samples;
                    double scale = audio_volume / 256.;
                    for (i = 0; i < (decoded_data_size / sizeof(*volp)); i++) {
                        *volp++ *= scale;
                    }
                    break;
                }
                default:
                    av_log(NULL, AV_LOG_FATAL,
                           "Audio volume adjustment on sample format %s is not supported.\n",
                           av_get_sample_fmt_name(ist->st->codec->sample_fmt));
                    exit_program(1);
                }
            }
        }

        /* frame rate emulation */
        if (input_files[ist->file_index].rate_emu) {
            int64_t pts = av_rescale(ist->pts, 1000000, AV_TIME_BASE);
            int64_t now = av_gettime() - ist->start;
            if (pts > now)
                usleep(pts - now);
        }
        /* if output time reached then transcode raw format,
           encode packets and output them */
        for (i = 0; i < nb_ostreams; i++) {
            OutputFile *of = &output_files[ost_table[i].file_index];
            int frame_size;

            ost = &ost_table[i];
            if (ost->source_index != ist_index)
                continue;

            if (of->start_time && ist->pts < of->start_time)
                continue;

            if (of->recording_time != INT64_MAX &&
                av_compare_ts(ist->pts, AV_TIME_BASE_Q, of->recording_time + of->start_time,
                              (AVRational){1, 1000000}) >= 0) {
                ost->is_past_recording_time = 1;
                continue;
            }

#if CONFIG_AVFILTER
            frame_available = ist->st->codec->codec_type != AVMEDIA_TYPE_VIDEO ||
                !ost->output_video_filter || avfilter_poll_frame(ost->output_video_filter->inputs[0]);
            while (frame_available) {
                if (ist->st->codec->codec_type == AVMEDIA_TYPE_VIDEO && ost->output_video_filter) {
                    AVRational ist_pts_tb = ost->output_video_filter->inputs[0]->time_base;
                    if (av_buffersink_get_buffer_ref(ost->output_video_filter, &ost->picref, 0) < 0)
                        goto cont;
                    if (!filtered_frame && !(filtered_frame = avcodec_alloc_frame())) {
                        ret = AVERROR(ENOMEM);
                        goto fail;
                    }
                    *filtered_frame= *decoded_frame; //for me_threshold
                    if (ost->picref) {
                        avfilter_fill_frame_from_video_buffer_ref(filtered_frame, ost->picref);
                        ist->pts = av_rescale_q(ost->picref->pts, ist_pts_tb, AV_TIME_BASE_Q);
                    }
                }
#else
                filtered_frame = decoded_frame;
#endif
                os = output_files[ost->file_index].ctx;

                /* set the input output pts pairs */
                //ost->sync_ipts = (double)(ist->pts + input_files[ist->file_index].ts_offset - start_time)/ AV_TIME_BASE;

                if (ost->encoding_needed) {
                    av_assert0(ist->decoding_needed);
                    switch(ost->st->codec->codec_type) {
                    case AVMEDIA_TYPE_AUDIO:
                        do_audio_out(os, ost, ist, decoded_data_buf, decoded_data_size);
                        break;
                    case AVMEDIA_TYPE_VIDEO:
#if CONFIG_AVFILTER
                        if (ost->picref->video && !ost->frame_aspect_ratio)
                            ost->st->codec->sample_aspect_ratio = ost->picref->video->sample_aspect_ratio;
#endif
                        do_video_out(os, ost, ist, filtered_frame, &frame_size,
                                     same_quant ? quality : ost->st->codec->global_quality);
                        if (vstats_filename && frame_size)
                            do_video_stats(os, ost, frame_size);
                        break;
                    case AVMEDIA_TYPE_SUBTITLE:
                        do_subtitle_out(os, ost, ist, &subtitle,
                                        pkt->pts);
                        break;
                    default:
                        abort();
                    }
                } else {
                    AVPicture pict;
                    AVPacket opkt;
                    int64_t ost_tb_start_time= av_rescale_q(of->start_time, AV_TIME_BASE_Q, ost->st->time_base);
                    av_init_packet(&opkt);

                    if ((!ost->frame_number && !(pkt->flags & AV_PKT_FLAG_KEY)) &&
                        !ost->copy_initial_nonkeyframes)
#if !CONFIG_AVFILTER
                        continue;
#else
                        goto cont;
#endif

                    /* no reencoding needed : output the packet directly */
                    /* force the input stream PTS */

                    if(ost->st->codec->codec_type == AVMEDIA_TYPE_AUDIO)
                        audio_size += data_size;
                    else if (ost->st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
                        video_size += data_size;
                        ost->sync_opts++;
                    }

                    opkt.stream_index= ost->index;
                    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->pts, 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;

                    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->st->codec->codec_id != CODEC_ID_H264
                       && ost->st->codec->codec_id != CODEC_ID_MPEG1VIDEO
                       && ost->st->codec->codec_id != CODEC_ID_MPEG2VIDEO
                       ) {
                        if(av_parser_change(ist->st->parser, ost->st->codec, &opkt.data, &opkt.size, data_buf, data_size, pkt->flags & AV_PKT_FLAG_KEY))
                            opkt.destruct= av_destruct_packet;
                    } else {
                        opkt.data = data_buf;
                        opkt.size = data_size;
                    }

                    if (os->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(os, &opkt, ost->st->codec, ost->bitstream_filters);
                    ost->st->codec->frame_number++;
                    ost->frame_number++;
                    av_free_packet(&opkt);
                }
#if CONFIG_AVFILTER
                cont:
                frame_available = (ist->st->codec->codec_type == AVMEDIA_TYPE_VIDEO) &&
                                   ost->output_video_filter && avfilter_poll_frame(ost->output_video_filter->inputs[0]);
                avfilter_unref_buffer(ost->picref);
            }
            av_freep(&filtered_frame);
#endif
        }

fail:
        av_free(buffer_to_free);
        /* XXX: allocate the subtitles in the codec ? */
        if (subtitle_to_free) {
            avsubtitle_free(subtitle_to_free);
            subtitle_to_free = NULL;
        }
        av_freep(&decoded_frame);