ffmpeg.c

                    ipts_min = ipts;
                    if(input_sync ) file_index = ist->file_index;
                }
                if(opts < opts_min) {
                    opts_min = opts;
                    if(!input_sync) file_index = ist->file_index;
                }
            }
            if(ost->frame_number >= max_frames[ost->st->codec->codec_type]){
                file_index= -1;
                break;
            }
        }
        /* if none, if is finished */
        if (file_index < 0) {
            break;
        }

        /* finish if recording time exhausted */
        if (recording_time > 0 && opts_min >= (recording_time / 1000000.0))
            break;

        /* finish if limit size exhausted */
        if (limit_filesize != 0 && (limit_filesize * 1024) < url_ftell(&output_files[0]->pb))
            break;

        /* read a frame from it and output it in the fifo */
        is = input_files[file_index];
        if (av_read_frame(is, &pkt) < 0) {
            file_table[file_index].eof_reached = 1;
            if (opt_shortest) break; else continue; //
        }

        if (!pkt.size) {
            stream_no_data = is;
        } else {
            stream_no_data = 0;
        }
        if (do_pkt_dump) {
            av_pkt_dump(stdout, &pkt, do_hex_dump);
        }
        /* the following test is needed in case new streams appear
           dynamically in stream : we ignore them */
        if (pkt.stream_index >= file_table[file_index].nb_streams)
            goto discard_packet;
        ist_index = file_table[file_index].ist_index + pkt.stream_index;
        ist = ist_table[ist_index];
        if (ist->discard)
            goto discard_packet;

//        fprintf(stderr, "next:%lld dts:%lld off:%lld %d\n", ist->next_pts, pkt.dts, input_files_ts_offset[ist->file_index], ist->st->codec->codec_type);
        if (pkt.dts != AV_NOPTS_VALUE && ist->next_pts != AV_NOPTS_VALUE) {
            int64_t delta= av_rescale_q(pkt.dts, ist->st->time_base, AV_TIME_BASE_Q) - ist->next_pts;
            if(ABS(delta) > 10LL*AV_TIME_BASE && !copy_ts){
                input_files_ts_offset[ist->file_index]-= delta;
                if (verbose > 2)
                    fprintf(stderr, "timestamp discontinuity %lld, new offset= %lld\n", delta, input_files_ts_offset[ist->file_index]);
                for(i=0; i<file_table[file_index].nb_streams; i++){
                    int index= file_table[file_index].ist_index + i;
                    ist_table[index]->next_pts += delta;
                    ist_table[index]->is_start=1;
                }
            }
        }

        //fprintf(stderr,"read #%d.%d size=%d\n", ist->file_index, ist->index, pkt.size);
        if (output_packet(ist, ist_index, ost_table, nb_ostreams, &pkt) < 0) {

            if (verbose >= 0)
                fprintf(stderr, "Error while decoding stream #%d.%d\n",
                        ist->file_index, ist->index);

            av_free_packet(&pkt);
            goto redo;
        }

    discard_packet:
        av_free_packet(&pkt);
        
        /* dump report by using the output first video and audio streams */
        print_report(output_files, ost_table, nb_ostreams, 0);
    }

    /* at the end of stream, we must flush the decoder buffers */
    for(i=0;i<nb_istreams;i++) {
        ist = ist_table[i];
        if (ist->decoding_needed) {
            output_packet(ist, i, ost_table, nb_ostreams, NULL);
        }
    }

    term_exit();

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

    /* dump report by using the first video and audio streams */
    print_report(output_files, ost_table, nb_ostreams, 1);

    /* close each encoder */
    for(i=0;i<nb_ostreams;i++) {
        ost = ost_table[i];
        if (ost->encoding_needed) {
            av_freep(&ost->st->codec->stats_in);
            avcodec_close(ost->st->codec);
        }
    }
    
    /* close each decoder */
    for(i=0;i<nb_istreams;i++) {
        ist = ist_table[i];
        if (ist->decoding_needed) {
            avcodec_close(ist->st->codec);
        }
    }

    /* finished ! */
    
    ret = 0;
 fail1:
    av_freep(&bit_buffer);
    av_free(file_table);

    if (ist_table) {
        for(i=0;i<nb_istreams;i++) {
            ist = ist_table[i];
            av_free(ist);
        }
        av_free(ist_table);
    }
    if (ost_table) {
        for(i=0;i<nb_ostreams;i++) {
            ost = ost_table[i];
            if (ost) {
                if (ost->logfile) {
                    fclose(ost->logfile);
                    ost->logfile = NULL;
                }
                fifo_free(&ost->fifo); /* works even if fifo is not
                                          initialized but set to zero */
                av_free(ost->pict_tmp.data[0]);
                if (ost->video_resample)
                    img_resample_close(ost->img_resample_ctx);
                if (ost->audio_resample)
                    audio_resample_close(ost->resample);
                av_free(ost);
            }
        }
        av_free(ost_table);
    }
    return ret;
 fail:
    ret = -ENOMEM;
    goto fail1;
}

#if 0
int file_read(const char *filename)
{
    URLContext *h;
    unsigned char buffer[1024];
    int len, i;

    if (url_open(&h, filename, O_RDONLY) < 0) {
        printf("could not open '%s'\n", filename);
        return -1;
    }
    for(;;) {
        len = url_read(h, buffer, sizeof(buffer));
        if (len <= 0)
            break;
        for(i=0;i<len;i++) putchar(buffer[i]);
    }
    url_close(h);
    return 0;
}
#endif

static void opt_image_format(const char *arg)
{
    AVImageFormat *f;
    
    for(f = first_image_format; f != NULL; f = f->next) {
        if (!strcmp(arg, f->name))
            break;
    }
    if (!f) {
        fprintf(stderr, "Unknown image format: '%s'\n", arg);
        exit(1);
    }
    image_format = f;
}

static void opt_format(const char *arg)
{
    /* compatibility stuff for pgmyuv */
    if (!strcmp(arg, "pgmyuv")) {
        pgmyuv_compatibility_hack=1;
//        opt_image_format(arg);
        arg = "image2";
    }

    file_iformat = av_find_input_format(arg);
    file_oformat = guess_format(arg, NULL, NULL);
    if (!file_iformat && !file_oformat) {
        fprintf(stderr, "Unknown input or output format: %s\n", arg);
        exit(1);
    }
}

static void opt_video_bitrate(const char *arg)
{
    video_bit_rate = atoi(arg) * 1000;
}

static void opt_video_bitrate_tolerance(const char *arg)
{
    video_bit_rate_tolerance = atoi(arg) * 1000;
}

static void opt_video_bitrate_max(const char *arg)
{
    video_rc_max_rate = atoi(arg) * 1000;
}

static void opt_video_bitrate_min(const char *arg)
{
    video_rc_min_rate = atoi(arg) * 1000;
}

static void opt_video_buffer_size(const char *arg)
{
    video_rc_buffer_size = atoi(arg) * 8*1024;
}

static void opt_video_rc_eq(char *arg)
{
    video_rc_eq = arg;
}

static void opt_video_rc_override_string(char *arg)
{
    video_rc_override_string = arg;
}


static void opt_workaround_bugs(const char *arg)
{
    workaround_bugs = atoi(arg);
}

static void opt_me_threshold(const char *arg)
{
    me_threshold = atoi(arg);
}

static void opt_mb_threshold(const char *arg)
{
    mb_threshold = atoi(arg);
}

static void opt_error_resilience(const char *arg)
{
    error_resilience = atoi(arg);
}

static void opt_error_concealment(const char *arg)
{
    error_concealment = atoi(arg);
}

static void opt_verbose(const char *arg)
{
    verbose = atoi(arg);
    av_log_set_level(atoi(arg));
}

static void opt_frame_rate(const char *arg)
{
    if (parse_frame_rate(&frame_rate, &frame_rate_base, arg) < 0) {
        fprintf(stderr, "Incorrect frame rate\n");
	exit(1);
    }
}

static void opt_frame_crop_top(const char *arg)
{
    frame_topBand = atoi(arg); 
    if (frame_topBand < 0) {
        fprintf(stderr, "Incorrect top crop size\n");
        exit(1);
    }
    if ((frame_topBand % 2) != 0) {
        fprintf(stderr, "Top crop size must be a multiple of 2\n");
        exit(1);
    }
    if ((frame_topBand) >= frame_height){
    	fprintf(stderr, "Vertical crop dimensions are outside the range of the original image.\nRemember to crop first and scale second.\n");
        exit(1);
    }
    frame_height -= frame_topBand;
}

static void opt_frame_crop_bottom(const char *arg)
{
    frame_bottomBand = atoi(arg);
    if (frame_bottomBand < 0) {
        fprintf(stderr, "Incorrect bottom crop size\n");
        exit(1);
    }
    if ((frame_bottomBand % 2) != 0) {
        fprintf(stderr, "Bottom crop size must be a multiple of 2\n");
        exit(1);        
    }
    if ((frame_bottomBand) >= frame_height){
    	fprintf(stderr, "Vertical crop dimensions are outside the range of the original image.\nRemember to crop first and scale second.\n");
        exit(1);
    }
    frame_height -= frame_bottomBand;
}

static void opt_frame_crop_left(const char *arg)
{
    frame_leftBand = atoi(arg);
    if (frame_leftBand < 0) {
        fprintf(stderr, "Incorrect left crop size\n");
        exit(1);
    }
    if ((frame_leftBand % 2) != 0) {
        fprintf(stderr, "Left crop size must be a multiple of 2\n");
        exit(1);
    }
    if ((frame_leftBand) >= frame_width){
    	fprintf(stderr, "Horizontal crop dimensions are outside the range of the original image.\nRemember to crop first and scale second.\n");
        exit(1);
    }
    frame_width -= frame_leftBand;
}

static void opt_frame_crop_right(const char *arg)
{
    frame_rightBand = atoi(arg);
    if (frame_rightBand < 0) {
        fprintf(stderr, "Incorrect right crop size\n");
        exit(1);
    }
    if ((frame_rightBand % 2) != 0) {
        fprintf(stderr, "Right crop size must be a multiple of 2\n");
        exit(1);        
    }
    if ((frame_rightBand) >= frame_width){
    	fprintf(stderr, "Horizontal crop dimensions are outside the range of the original image.\nRemember to crop first and scale second.\n");
        exit(1);
    }
    frame_width -= frame_rightBand;
}

static void opt_frame_size(const char *arg)
{
    if (parse_image_size(&frame_width, &frame_height, arg) < 0) {
        fprintf(stderr, "Incorrect frame size\n");
        exit(1);
    }
    if ((frame_width % 2) != 0 || (frame_height % 2) != 0) {
        fprintf(stderr, "Frame size must be a multiple of 2\n");
        exit(1);
    }
}


#define SCALEBITS 10
#define ONE_HALF  (1 << (SCALEBITS - 1))
#define FIX(x)	  ((int) ((x) * (1<<SCALEBITS) + 0.5))

#define RGB_TO_Y(r, g, b) \
((FIX(0.29900) * (r) + FIX(0.58700) * (g) + \
  FIX(0.11400) * (b) + ONE_HALF) >> SCALEBITS)

#define RGB_TO_U(r1, g1, b1, shift)\
(((- FIX(0.16874) * r1 - FIX(0.33126) * g1 +         \
     FIX(0.50000) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)

#define RGB_TO_V(r1, g1, b1, shift)\
(((FIX(0.50000) * r1 - FIX(0.41869) * g1 -           \
   FIX(0.08131) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)

static void opt_pad_color(const char *arg) {
    /* Input is expected to be six hex digits similar to
       how colors are expressed in html tags (but without the #) */
    int rgb = strtol(arg, NULL, 16);
    int r,g,b;
    
    r = (rgb >> 16); 
    g = ((rgb >> 8) & 255);
    b = (rgb & 255);

    padcolor[0] = RGB_TO_Y(r,g,b);
    padcolor[1] = RGB_TO_U(r,g,b,0);
    padcolor[2] = RGB_TO_V(r,g,b,0);
}

static void opt_frame_pad_top(const char *arg)
{
    frame_padtop = atoi(arg); 
    if (frame_padtop < 0) {
        fprintf(stderr, "Incorrect top pad size\n");
        exit(1);
    }
    if ((frame_padtop % 2) != 0) {
        fprintf(stderr, "Top pad size must be a multiple of 2\n");
        exit(1);
    }
}

static void opt_frame_pad_bottom(const char *arg)
{
    frame_padbottom = atoi(arg); 
    if (frame_padbottom < 0) {
        fprintf(stderr, "Incorrect bottom pad size\n");
        exit(1);
    }
    if ((frame_padbottom % 2) != 0) {
        fprintf(stderr, "Bottom pad size must be a multiple of 2\n");
        exit(1);
    }
}


static void opt_frame_pad_left(const char *arg)
{
    frame_padleft = atoi(arg); 
    if (frame_padleft < 0) {
        fprintf(stderr, "Incorrect left pad size\n");
        exit(1);
    }
    if ((frame_padleft % 2) != 0) {
        fprintf(stderr, "Left pad size must be a multiple of 2\n");
        exit(1);
    }
}


static void opt_frame_pad_right(const char *arg)
{
    frame_padright = atoi(arg); 
    if (frame_padright < 0) {
        fprintf(stderr, "Incorrect right pad size\n");
        exit(1);
    }
    if ((frame_padright % 2) != 0) {
        fprintf(stderr, "Right pad size must be a multiple of 2\n");
        exit(1);
    }
}


static void opt_frame_pix_fmt(const char *arg)
{
    frame_pix_fmt = avcodec_get_pix_fmt(arg);
}

static void opt_frame_aspect_ratio(const char *arg)
{
    int x = 0, y = 0;
    double ar = 0;
    const char *p;
    
    p = strchr(arg, ':');
    if (p) {
        x = strtol(arg, (char **)&arg, 10);
	if (arg == p)
	    y = strtol(arg+1, (char **)&arg, 10);
	if (x > 0 && y > 0)
	    ar = (double)x / (double)y;
    } else
        ar = strtod(arg, (char **)&arg);

    if (!ar) {
        fprintf(stderr, "Incorrect aspect ratio specification.\n");
	exit(1);
    }
    frame_aspect_ratio = ar;
}

static void opt_gop_size(const char *arg)
{
    gop_size = atoi(arg);
}

static void opt_b_frames(const char *arg)
{
    b_frames = atoi(arg);
    if (b_frames > FF_MAX_B_FRAMES) {
        fprintf(stderr, "\nCannot have more than %d B frames, increase FF_MAX_B_FRAMES.\n", FF_MAX_B_FRAMES);
        exit(1);
    } else if (b_frames < 1) {
        fprintf(stderr, "\nNumber of B frames must be higher than 0\n");
        exit(1);
    }
}

static void opt_pre_me(const char *arg)
{
    pre_me = atoi(arg);
}

static void opt_lumi_mask(const char *arg)
{
    lumi_mask = atof(arg);
}

static void opt_dark_mask(const char *arg)
{
    dark_mask = atof(arg);
}

static void opt_scplx_mask(const char *arg)
{
    scplx_mask = atof(arg);
}

static void opt_tcplx_mask(const char *arg)
{
    tcplx_mask = atof(arg);
}

static void opt_p_mask(const char *arg)
{
    p_mask = atof(arg);
}

static void opt_qscale(const char *arg)
{
    video_qscale = atof(arg);
    if (video_qscale < 0.01 ||
        video_qscale > 255) {
        fprintf(stderr, "qscale must be >= 0.01 and <= 255\n");
        exit(1);
    }
}

static void opt_qsquish(const char *arg)
{
    video_qsquish = atof(arg);
    if (video_qsquish < 0.0 ||
        video_qsquish > 99.0) {
        fprintf(stderr, "qsquish must be >= 0.0 and <= 99.0\n");
        exit(1);
    }
}

static void opt_lmax(const char *arg)
{
    video_lmax = atof(arg)*FF_QP2LAMBDA;
}

static void opt_lmin(const char *arg)
{
    video_lmin = atof(arg)*FF_QP2LAMBDA;
}

static void opt_qmin(const char *arg)
{
    video_qmin = atoi(arg);
    if (video_qmin < 1 ||
        video_qmin > 31) {
        fprintf(stderr, "qmin must be >= 1 and <= 31\n");
        exit(1);
    }
}

static void opt_qmax(const char *arg)
{
    video_qmax = atoi(arg);
    if (video_qmax < 1 ||
        video_qmax > 31) {
        fprintf(stderr, "qmax must be >= 1 and <= 31\n");
        exit(1);
    }
}

static void opt_mb_lmin(const char *arg)
{
    video_mb_lmin = atof(arg)*FF_QP2LAMBDA;
    if (video_mb_lmin < 1 ||
        video_mb_lmin > FF_LAMBDA_MAX) {
        fprintf(stderr, "mblmin must be >= 1 and <= %d\n", FF_LAMBDA_MAX / FF_QP2LAMBDA);
        exit(1);
    }
}

static void opt_mb_lmax(const char *arg)
{
    video_mb_lmax = atof(arg)*FF_QP2LAMBDA;
    if (video_mb_lmax < 1 ||
        video_mb_lmax > FF_LAMBDA_MAX) {
        fprintf(stderr, "mblmax must be >= 1 and <= %d\n", FF_LAMBDA_MAX / FF_QP2LAMBDA);
        exit(1);
    }
}

static void opt_qdiff(const char *arg)
{
    video_qdiff = atoi(arg);
    if (video_qdiff < 0 ||
        video_qdiff > 31) {
        fprintf(stderr, "qdiff must be >= 1 and <= 31\n");
        exit(1);
    }
}

static void opt_qblur(const char *arg)
{
    video_qblur = atof(arg);
}

static void opt_qcomp(const char *arg)
{
    video_qcomp = atof(arg);
}

static void opt_rc_initial_cplx(const char *arg)
{
    video_rc_initial_cplx = atof(arg);
}
static void opt_b_qfactor(const char *arg)
{
    video_b_qfactor = atof(arg);
}
static void opt_i_qfactor(const char *arg)
{
    video_i_qfactor = atof(arg);
}
static void opt_b_qoffset(const char *arg)
{
    video_b_qoffset = atof(arg);
}
static void opt_i_qoffset(const char *arg)
{
    video_i_qoffset = atof(arg);
}

static void opt_ibias(const char *arg)
{
    video_intra_quant_bias = atoi(arg);
}
static void opt_pbias(const char *arg)
{
    video_inter_quant_bias = atoi(arg);
}

static void opt_packet_size(const char *arg)
{
    packet_size= atoi(arg);
}

static void opt_error_rate(const char *arg)
{
    error_rate= atoi(arg);
}

static void opt_strict(const char *arg)
{
    strict= atoi(arg);
}

static void opt_top_field_first(const char *arg)
{
    top_field_first= atoi(arg);
}

static void opt_noise_reduction(const char *arg)
{
    noise_reduction= atoi(arg);
}

static void opt_qns(const char *arg)
{
    qns= atoi(arg);
}

static void opt_sc_threshold(const char *arg)
{
    sc_threshold= atoi(arg);
}

static void opt_me_range(const char *arg)
{
    me_range = atoi(arg);
}

static void opt_thread_count(const char *arg)
{
    thread_count= atoi(arg);
#if !defined(HAVE_THREADS)
    if (verbose >= 0)
        fprintf(stderr, "Warning: not compiled with thread support, using thread emulation\n");
#endif
}

static void opt_audio_bitrate(const char *arg)
{
    audio_bit_rate = atoi(arg) * 1000;
}

static void opt_audio_rate(const char *arg)
{
    audio_sample_rate = atoi(arg);
}

static void opt_audio_channels(const char *arg)
{
    audio_channels = atoi(arg);
}

static void opt_video_device(const char *arg)
{
    video_device = av_strdup(arg);
}

static void opt_grab_device(const char *arg)
{
    grab_device = av_strdup(arg);
}

static void opt_video_channel(const char *arg)
{
    video_channel = strtol(arg, NULL, 0);
}

static void opt_video_standard(const char *arg)
{
    video_standard = av_strdup(arg);
}

static void opt_audio_device(const char *arg)
{
    audio_device = av_strdup(arg);
}

static void opt_codec(int *pstream_copy, int *pcodec_id,
                      int codec_type, const char *arg)
{
    AVCodec *p;

    if (!strcmp(arg, "copy")) {
        *pstream_copy = 1;
    } else {
        p = first_avcodec;
        while (p) {
            if (!strcmp(p->name, arg) && p->type == codec_type)
                break;
            p = p->next;
        }
        if (p == NULL) {
            fprintf(stderr, "Unknown codec '%s'\n", arg);
            exit(1);
        } else {
            *pcodec_id = p->id;
        }
    }
}

static void opt_audio_codec(const char *arg)
{
    opt_codec(&audio_stream_copy, &audio_codec_id, CODEC_TYPE_AUDIO, arg);
}

static void opt_audio_tag(const char *arg)
{
    char *tail;
    audio_codec_tag= strtol(arg, &tail, 0);

    if(!tail || *tail)
        audio_codec_tag= arg[0] + (arg[1]<<8) + (arg[2]<<16) + (arg[3]<<24);
}

static void opt_video_tag(const char *arg)
{
    char *tail;
    video_codec_tag= strtol(arg, &tail, 0);

    if(!tail || *tail)
        video_codec_tag= arg[0] + (arg[1]<<8) + (arg[2]<<16) + (arg[3]<<24);
}

static void add_frame_hooker(const char *arg)
{
    int argc = 0;
    char *argv[64];
    int i;
    char *args = av_strdup(arg);

    using_vhook = 1;

    argv[0] = strtok(args, " ");
    while (argc < 62 && (argv[++argc] = strtok(NULL, " "))) {
    }

    i = frame_hook_add(argc, argv);

    if (i != 0) {
        fprintf(stderr, "Failed to add video hook function: %s\n", arg);
        exit(1);
    }
}

const char *motion_str[] = {
    "zero",
    "full",
    "log",
    "phods",
    "epzs",
    "x1",
    NULL,
};

static void opt_motion_estimation(const char *arg)
{
    const char **p;
    p = motion_str;
    for(;;) {
        if (!*p) {
            fprintf(stderr, "Unknown motion estimation method '%s'\n", arg);
            exit(1);
        }
        if (!strcmp(*p, arg))
            break;
        p++;
    }
    me_method = (p - motion_str) + 1;
}

static void opt_video_codec(const char *arg)
{
    opt_codec(&video_stream_copy, &video_codec_id, CODEC_TYPE_VIDEO, arg);
}

static void opt_subtitle_codec(const char *arg)
{
    opt_codec(&subtitle_stream_copy, &subtitle_codec_id, CODEC_TYPE_SUBTITLE, arg);
}

static void opt_map(const char *arg)
{
    AVStreamMap *m;
    const char *p;

    p = arg;
    m = &stream_maps[nb_stream_maps++];

    m->file_index = strtol(arg, (char **)&p, 0);
    if (*p)
        p++;

    m->stream_index = strtol(p, (char **)&p, 0);
    if (*p) {
        p++;
        m->sync_file_index = strtol(p, (char **)&p, 0);
        if (*p)
            p++;
        m->sync_stream_index = strtol(p, (char **)&p, 0);
    } else {
        m->sync_file_index = m->file_index;
        m->sync_stream_index = m->stream_index;
    }
}

static void opt_map_meta_data(const char *arg)
{
    AVMetaDataMap *m;
    const char *p;
	
    p = arg;
    m = &meta_data_maps[nb_meta_data_maps++];

    m->out_file = strtol(arg, (char **)&p, 0);
    if (*p)
        p++;

    m->in_file = strtol(p, (char **)&p, 0);
}

static void opt_recording_time(const char *arg)
{
    recording_time = parse_date(arg, 1);
}

static void opt_start_time(const char *arg)
{
    start_time = parse_date(arg, 1);
}

static void opt_rec_timestamp(const char *arg)
{
    rec_timestamp = parse_date(arg, 0) / 1000000;
}

static void opt_input_ts_offset(const char *arg)
{
    input_ts_offset = parse_date(arg, 1);
}

static void opt_input_file(const char *filename)
{
    AVFormatContext *ic;
    AVFormatParameters params, *ap = &params;
    int err, i, ret, rfps, rfps_base;
    int64_t timestamp;

    if (!strcmp(filename, "-"))
        filename = "pipe:";

    using_stdin |= !strncmp(filename, "pipe:", 5) || 
                   !strcmp( filename, "/dev/stdin" );

    /* get default parameters from command line */
    memset(ap, 0, sizeof(*ap));
    ap->sample_rate = audio_sample_rate;
    ap->channels = audio_channels;
    ap->time_base.den = frame_rate;
    ap->time_base.num = frame_rate_base;
    ap->width = frame_width + frame_padleft + frame_padright;
    ap->height = frame_height + frame_padtop + frame_padbottom;
    ap->image_format = image_format;
    ap->pix_fmt = frame_pix_fmt;
    ap->device  = grab_device;
    ap->channel = video_channel;
    ap->standard = video_standard;
    ap->video_codec_id = video_codec_id;
    ap->audio_codec_id = audio_codec_id;
    if(pgmyuv_compatibility_hack)
        ap->video_codec_id= CODEC_ID_PGMYUV;

    /* open the input file with generic libav function */
    err = av_open_input_file(&ic, filename, file_iformat, 0, ap);
    if (err < 0) {
        print_error(filename, err);
        exit(1);
    }

    if(genpts)
        ic->flags|= AVFMT_FLAG_GENPTS;
    
    /* If not enough info to get the stream parameters, we decode the
       first frames to get it. (used in mpeg case for example) */
    ret = av_find_stream_info(ic);
    if (ret < 0 && verbose >= 0) {
        fprintf(stderr, "%s: could not find codec parameters\n", filename);
        exit(1);
    }

    timestamp = start_time;
    /* add the stream start time */
    if (ic->start_time != AV_NOPTS_VALUE)
        timestamp += ic->start_time;

    /* if seeking requested, we execute it */
    if (start_time != 0) {
        ret = av_seek_frame(ic, -1, timestamp, AVSEEK_FLAG_BACKWARD);
        if (ret < 0) {
            fprintf(stderr, "%s: could not seek to position %0.3f\n", 
                    filename, (double)timestamp / AV_TIME_BASE);
        }
        /* reset seek info */
        start_time = 0;
    }

    /* update the current parameters so that they match the one of the input stream */
    for(i=0;i<ic->nb_streams;i++) {
        int j;
        AVCodecContext *enc = ic->streams[i]->codec;
#if defined(HAVE_THREADS)
        if(thread_count>1)
            avcodec_thread_init(enc, thread_count);
#endif
        enc->thread_count= thread_count;
        switch(enc->codec_type) {
        case CODEC_TYPE_AUDIO:
            for(j=0; j<opt_name_count; j++){
                AVOption *opt;
                double d= av_get_double(avctx_opts, opt_names[j], &opt);
                if(d==d && (opt->flags&AV_OPT_FLAG_AUDIO_PARAM) && (opt->flags&AV_OPT_FLAG_DECODING_PARAM))
                    av_set_double(enc, opt_names[j], d);
            }
            //fprintf(stderr, "\nInput Audio channels: %d", enc->channels);
            audio_channels = enc->channels;
            audio_sample_rate = enc->sample_rate;
            if(audio_disable)
                ic->streams[i]->discard= AVDISCARD_ALL;
            break;
        case CODEC_TYPE_VIDEO:
            for(j=0; j<opt_name_count; j++){
                AVOption *opt;
                double d= av_get_double(avctx_opts, opt_names[j], &opt);
                if(d==d && (opt->flags&AV_OPT_FLAG_VIDEO_PARAM) && (opt->flags&AV_OPT_FLAG_DECODING_PARAM))
                    av_set_double(enc, opt_names[j], d);