ffmpeg.c

    if(!name)
        return CODEC_ID_NONE;
    codec = encoder ?
        avcodec_find_encoder_by_name(name) :
        avcodec_find_decoder_by_name(name);
    if(!codec) {
        av_log(NULL, AV_LOG_ERROR, "Unknown %s '%s'\n", codec_string, name);
        exit_program(1);
    }
    if(codec->type != type) {
        av_log(NULL, AV_LOG_ERROR, "Invalid %s type '%s'\n", codec_string, name);
        exit_program(1);
    }
    return codec->id;
}

static AVCodec *choose_codec(AVFormatContext *s, AVStream *st, enum AVMediaType type, AVDictionary *codec_names)
{
    AVDictionaryEntry *e = NULL;
    char *codec_name = NULL;
    int ret;

    while (e = av_dict_get(codec_names, "", e, AV_DICT_IGNORE_SUFFIX)) {
        char *p = strchr(e->key, ':');

        if ((ret = check_stream_specifier(s, st, p ? p + 1 : "")) > 0)
            codec_name = e->value;
        else if (ret < 0)
            exit_program(1);
    }

    if (!codec_name) {
        if (s->oformat) {
            st->codec->codec_id = av_guess_codec(s->oformat, NULL, s->filename, NULL, type);
            return avcodec_find_encoder(st->codec->codec_id);
        }
    } else if (!strcmp(codec_name, "copy"))
        st->stream_copy = 1;
    else {
        st->codec->codec_id = find_codec_or_die(codec_name, type, s->iformat == NULL);
        return s->oformat ? avcodec_find_encoder_by_name(codec_name) :
                            avcodec_find_decoder_by_name(codec_name);
    }

    return NULL;
}

/**
 * Add all the streams from the given input file to the global
 * list of input streams.
 */
static void add_input_streams(AVFormatContext *ic)
{
    int i, rfps, rfps_base, ret;

    for (i = 0; i < ic->nb_streams; i++) {
        AVStream *st = ic->streams[i];
        AVCodecContext *dec = st->codec;
        AVDictionaryEntry *e = NULL;
        InputStream *ist;
        char *scale = NULL;

        dec->thread_count = thread_count;

        input_streams = grow_array(input_streams, sizeof(*input_streams), &nb_input_streams, nb_input_streams + 1);
        ist = &input_streams[nb_input_streams - 1];
        ist->st = st;
        ist->file_index = nb_input_files;
        ist->discard = 1;
        ist->opts = filter_codec_opts(codec_opts, ist->st->codec->codec_id, ic, st);

        while (e = av_dict_get(ts_scale, "", e, AV_DICT_IGNORE_SUFFIX)) {
            char *p = strchr(e->key, ':');

            if ((ret = check_stream_specifier(ic, st, p ? p + 1 : "")) > 0)
                scale = e->value;
            else if (ret < 0)
                exit_program(1);
        }
        if (scale)
            ist->ts_scale = strtod(scale, NULL);

        ist->dec = choose_codec(ic, st, dec->codec_type, codec_names);

        switch (dec->codec_type) {
        case AVMEDIA_TYPE_AUDIO:
            if(!ist->dec)
                ist->dec = avcodec_find_decoder(dec->codec_id);
            if(audio_disable)
                st->discard= AVDISCARD_ALL;
            break;
        case AVMEDIA_TYPE_VIDEO:
            if(!ist->dec)
                ist->dec = avcodec_find_decoder(dec->codec_id);
            rfps      = ic->streams[i]->r_frame_rate.num;
            rfps_base = ic->streams[i]->r_frame_rate.den;
            if (dec->lowres) {
                dec->flags |= CODEC_FLAG_EMU_EDGE;
            }
            if(me_threshold)
                dec->debug |= FF_DEBUG_MV;

            if (dec->time_base.den != rfps*dec->ticks_per_frame || dec->time_base.num != rfps_base) {

                if (verbose >= 0)
                    fprintf(stderr,"\nSeems stream %d codec frame rate differs from container frame rate: %2.2f (%d/%d) -> %2.2f (%d/%d)\n",
                            i, (float)dec->time_base.den / dec->time_base.num, dec->time_base.den, dec->time_base.num,

                    (float)rfps / rfps_base, rfps, rfps_base);
            }

            if(video_disable)
                st->discard= AVDISCARD_ALL;
            else if(video_discard)
                st->discard= video_discard;
            break;
        case AVMEDIA_TYPE_DATA:
            break;
        case AVMEDIA_TYPE_SUBTITLE:
            if(!ist->dec)
                ist->dec = avcodec_find_decoder(dec->codec_id);
            if(subtitle_disable)
                st->discard = AVDISCARD_ALL;
            break;
        case AVMEDIA_TYPE_ATTACHMENT:
        case AVMEDIA_TYPE_UNKNOWN:
            break;
        default:
            abort();
        }
    }
}

static int opt_input_file(const char *opt, const char *filename)
{
    AVFormatContext *ic;
    AVInputFormat *file_iformat = NULL;
    int err, i, ret;
    int64_t timestamp;
    uint8_t buf[128];
    AVDictionary **opts;
    int orig_nb_streams;                     // number of streams before avformat_find_stream_info

    if (last_asked_format) {
        if (!(file_iformat = av_find_input_format(last_asked_format))) {
            fprintf(stderr, "Unknown input format: '%s'\n", last_asked_format);
            exit_program(1);
        }
        last_asked_format = NULL;
    }

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

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

    /* get default parameters from command line */
    ic = avformat_alloc_context();
    if (!ic) {
        print_error(filename, AVERROR(ENOMEM));
        exit_program(1);
    }
    if (audio_sample_rate) {
        snprintf(buf, sizeof(buf), "%d", audio_sample_rate);
        av_dict_set(&format_opts, "sample_rate", buf, 0);
    }
    if (audio_channels) {
        snprintf(buf, sizeof(buf), "%d", audio_channels);
        av_dict_set(&format_opts, "channels", buf, 0);
    }
    if (frame_rate.num) {
        snprintf(buf, sizeof(buf), "%d/%d", frame_rate.num, frame_rate.den);
        av_dict_set(&format_opts, "framerate", buf, 0);
    }
    if (frame_width && frame_height) {
        snprintf(buf, sizeof(buf), "%dx%d", frame_width, frame_height);
        av_dict_set(&format_opts, "video_size", buf, 0);
    }
    if (frame_pix_fmt != PIX_FMT_NONE)
        av_dict_set(&format_opts, "pixel_format", av_get_pix_fmt_name(frame_pix_fmt), 0);

    ic->flags |= AVFMT_FLAG_NONBLOCK;

    if (loop_input) {
        av_log(NULL, AV_LOG_WARNING, "-loop_input is deprecated, use -loop 1\n");
        ic->loop_input = loop_input;
    }

    /* open the input file with generic libav function */
    err = avformat_open_input(&ic, filename, file_iformat, &format_opts);
    if (err < 0) {
        print_error(filename, err);
        exit_program(1);
    }
    assert_avoptions(format_opts);

    if(opt_programid) {
        int i, j;
        int found=0;
        for(i=0; i<ic->nb_streams; i++){
            ic->streams[i]->discard= AVDISCARD_ALL;
        }
        for(i=0; i<ic->nb_programs; i++){
            AVProgram *p= ic->programs[i];
            if(p->id != opt_programid){
                p->discard = AVDISCARD_ALL;
            }else{
                found=1;
                for(j=0; j<p->nb_stream_indexes; j++){
                    ic->streams[p->stream_index[j]]->discard= AVDISCARD_DEFAULT;
                }
            }
        }
        if(!found){
            fprintf(stderr, "Specified program id not found\n");
            exit_program(1);
        }
        opt_programid=0;
    }

    /* apply forced codec ids */
    for (i = 0; i < ic->nb_streams; i++)
        choose_codec(ic, ic->streams[i], ic->streams[i]->codec->codec_type, codec_names);

    /* Set AVCodecContext options for avformat_find_stream_info */
    opts = setup_find_stream_info_opts(ic, codec_opts);
    orig_nb_streams = ic->nb_streams;

    /* If not enough info to get the stream parameters, we decode the
       first frames to get it. (used in mpeg case for example) */
    ret = avformat_find_stream_info(ic, opts);
    if (ret < 0 && verbose >= 0) {
        fprintf(stderr, "%s: could not find codec parameters\n", filename);
        av_close_input_file(ic);
        exit_program(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 */
    add_input_streams(ic);

    /* dump the file content */
    if (verbose >= 0)
        av_dump_format(ic, nb_input_files, filename, 0);

    input_files = grow_array(input_files, sizeof(*input_files), &nb_input_files, nb_input_files + 1);
    input_files[nb_input_files - 1].ctx        = ic;
    input_files[nb_input_files - 1].ist_index  = nb_input_streams - ic->nb_streams;
    input_files[nb_input_files - 1].ts_offset  = input_ts_offset - (copy_ts ? 0 : timestamp);
    input_files[nb_input_files - 1].nb_streams = ic->nb_streams;

    top_field_first = -1;
    frame_rate    = (AVRational){0, 0};
    frame_pix_fmt = PIX_FMT_NONE;
    frame_height = 0;
    frame_width  = 0;
    audio_sample_rate = 0;
    audio_channels    = 0;
    audio_sample_fmt  = AV_SAMPLE_FMT_NONE;
    av_dict_free(&ts_scale);

    for (i = 0; i < orig_nb_streams; i++)
        av_dict_free(&opts[i]);
    av_freep(&opts);
    av_dict_free(&codec_names);
    uninit_opts();
    init_opts();
    return 0;
}

static void parse_forced_key_frames(char *kf, OutputStream *ost,
                                    AVCodecContext *avctx)
{
    char *p;
    int n = 1, i;
    int64_t t;

    for (p = kf; *p; p++)
        if (*p == ',')
            n++;
    ost->forced_kf_count = n;
    ost->forced_kf_pts = av_malloc(sizeof(*ost->forced_kf_pts) * n);
    if (!ost->forced_kf_pts) {
        av_log(NULL, AV_LOG_FATAL, "Could not allocate forced key frames array.\n");
        exit_program(1);
    }
    for (i = 0; i < n; i++) {
        p = i ? strchr(p, ',') + 1 : kf;
        t = parse_time_or_die("force_key_frames", p, 1);
        ost->forced_kf_pts[i] = av_rescale_q(t, AV_TIME_BASE_Q, avctx->time_base);
    }
}

static OutputStream *new_output_stream(AVFormatContext *oc, enum AVMediaType type)
{
    OutputStream *ost;
    AVStream *st = av_new_stream(oc, oc->nb_streams < nb_streamid_map ? streamid_map[oc->nb_streams] : 0);
    int idx      = oc->nb_streams - 1;

    if (!st) {
        av_log(NULL, AV_LOG_ERROR, "Could not alloc stream.\n");
        exit_program(1);
    }

    output_streams_for_file[nb_output_files] =
        grow_array(output_streams_for_file[nb_output_files],
                   sizeof(*output_streams_for_file[nb_output_files]),
                   &nb_output_streams_for_file[nb_output_files],
                   oc->nb_streams);
    ost = output_streams_for_file[nb_output_files][idx] =
        av_mallocz(sizeof(OutputStream));
    if (!ost) {
        fprintf(stderr, "Could not alloc output stream\n");
        exit_program(1);
    }
    ost->file_index = nb_output_files;
    ost->index = idx;
    ost->st    = st;
    st->codec->codec_type = type;
    ost->enc = choose_codec(oc, st, type, codec_names);
    if (ost->enc) {
        ost->opts  = filter_codec_opts(codec_opts, ost->enc->id, oc, st);
    }

    avcodec_get_context_defaults3(st->codec, ost->enc);
    st->codec->codec_type = type; // XXX hack, avcodec_get_context_defaults2() sets type to unknown for stream copy

    ost->sws_flags = av_get_int(sws_opts, "sws_flags", NULL);
    return ost;
}

static OutputStream *new_video_stream(AVFormatContext *oc)
{
    AVStream *st;
    OutputStream *ost;
    AVCodecContext *video_enc;

    ost = new_output_stream(oc, AVMEDIA_TYPE_VIDEO);
    st  = ost->st;
    if (!st->stream_copy) {
        ost->frame_aspect_ratio = frame_aspect_ratio;
        frame_aspect_ratio = 0;
#if CONFIG_AVFILTER
        ost->avfilter = vfilters;
        vfilters = NULL;
#endif
    }

    ost->bitstream_filters = video_bitstream_filters;
    video_bitstream_filters= NULL;

    st->codec->thread_count= thread_count;

    video_enc = st->codec;

    if(video_codec_tag)
        video_enc->codec_tag= video_codec_tag;

    if(oc->oformat->flags & AVFMT_GLOBALHEADER) {
        video_enc->flags |= CODEC_FLAG_GLOBAL_HEADER;
    }

    if (st->stream_copy) {
        video_enc->sample_aspect_ratio =
        st->sample_aspect_ratio = av_d2q(frame_aspect_ratio*frame_height/frame_width, 255);
    } else {
        const char *p;
        int i;

        if (frame_rate.num)
            ost->frame_rate = frame_rate;

        video_enc->width = frame_width;
        video_enc->height = frame_height;
        video_enc->pix_fmt = frame_pix_fmt;
        video_enc->bits_per_raw_sample = frame_bits_per_raw_sample;
        st->sample_aspect_ratio = video_enc->sample_aspect_ratio;

        if (intra_only)
            video_enc->gop_size = 0;
        if (video_qscale || same_quant) {
            video_enc->flags |= CODEC_FLAG_QSCALE;
            video_enc->global_quality = FF_QP2LAMBDA * video_qscale;
        }

        if(intra_matrix)
            video_enc->intra_matrix = intra_matrix;
        if(inter_matrix)
            video_enc->inter_matrix = inter_matrix;

        p= video_rc_override_string;
        for(i=0; p; i++){
            int start, end, q;
            int e=sscanf(p, "%d,%d,%d", &start, &end, &q);
            if(e!=3){
                fprintf(stderr, "error parsing rc_override\n");
                exit_program(1);
            }
            video_enc->rc_override=
                av_realloc(video_enc->rc_override,
                           sizeof(RcOverride)*(i+1));
            video_enc->rc_override[i].start_frame= start;
            video_enc->rc_override[i].end_frame  = end;
            if(q>0){
                video_enc->rc_override[i].qscale= q;
                video_enc->rc_override[i].quality_factor= 1.0;
            }
            else{
                video_enc->rc_override[i].qscale= 0;
                video_enc->rc_override[i].quality_factor= -q/100.0;
            }
            p= strchr(p, '/');
            if(p) p++;
        }
        video_enc->rc_override_count=i;
        if (!video_enc->rc_initial_buffer_occupancy)
            video_enc->rc_initial_buffer_occupancy = video_enc->rc_buffer_size*3/4;
        video_enc->me_threshold= me_threshold;
        video_enc->intra_dc_precision= intra_dc_precision - 8;

        if (do_psnr)
            video_enc->flags|= CODEC_FLAG_PSNR;

        /* two pass mode */
        if (do_pass) {
            if (do_pass == 1) {
                video_enc->flags |= CODEC_FLAG_PASS1;
            } else {
                video_enc->flags |= CODEC_FLAG_PASS2;
            }
        }

        if (forced_key_frames)
            parse_forced_key_frames(forced_key_frames, ost, video_enc);
    }
    if (video_language) {
        av_dict_set(&st->metadata, "language", video_language, 0);
        av_freep(&video_language);
    }

    /* reset some key parameters */
    video_disable = 0;
    av_freep(&forced_key_frames);
    frame_pix_fmt = PIX_FMT_NONE;
    return ost;
}

static OutputStream *new_audio_stream(AVFormatContext *oc)
{
    AVStream *st;
    OutputStream *ost;
    AVCodecContext *audio_enc;

    ost = new_output_stream(oc, AVMEDIA_TYPE_AUDIO);
    st  = ost->st;

    ost->bitstream_filters = audio_bitstream_filters;
    audio_bitstream_filters= NULL;

    st->codec->thread_count= thread_count;

    audio_enc = st->codec;
    audio_enc->codec_type = AVMEDIA_TYPE_AUDIO;

    if(audio_codec_tag)
        audio_enc->codec_tag= audio_codec_tag;

    if (oc->oformat->flags & AVFMT_GLOBALHEADER) {
        audio_enc->flags |= CODEC_FLAG_GLOBAL_HEADER;
    }
    if (!st->stream_copy) {
        if (audio_qscale > QSCALE_NONE) {
            audio_enc->flags |= CODEC_FLAG_QSCALE;
            audio_enc->global_quality = FF_QP2LAMBDA * audio_qscale;
        }
        if (audio_channels)
            audio_enc->channels = audio_channels;
        if (audio_sample_fmt != AV_SAMPLE_FMT_NONE)
            audio_enc->sample_fmt = audio_sample_fmt;
        if (audio_sample_rate)
            audio_enc->sample_rate = audio_sample_rate;
    }
    if (audio_language) {
        av_dict_set(&st->metadata, "language", audio_language, 0);
        av_freep(&audio_language);
    }

    /* reset some key parameters */
    audio_disable = 0;

    return ost;
}

static OutputStream *new_data_stream(AVFormatContext *oc)
{
    AVStream *st;
    OutputStream *ost;
    AVCodecContext *data_enc;

    ost = new_output_stream(oc, AVMEDIA_TYPE_DATA);
    st  = ost->st;
    data_enc = st->codec;
    if (!st->stream_copy) {
        fprintf(stderr, "Data stream encoding not supported yet (only streamcopy)\n");
        exit_program(1);
    }

    if (data_codec_tag)
        data_enc->codec_tag= data_codec_tag;

    if (oc->oformat->flags & AVFMT_GLOBALHEADER) {
        data_enc->flags |= CODEC_FLAG_GLOBAL_HEADER;
    }

    data_disable = 0;
    return ost;
}

static OutputStream *new_subtitle_stream(AVFormatContext *oc)
{
    AVStream *st;
    OutputStream *ost;
    AVCodecContext *subtitle_enc;

    ost = new_output_stream(oc, AVMEDIA_TYPE_SUBTITLE);
    st  = ost->st;
    subtitle_enc = st->codec;

    ost->bitstream_filters = subtitle_bitstream_filters;
    subtitle_bitstream_filters= NULL;

    subtitle_enc->codec_type = AVMEDIA_TYPE_SUBTITLE;

    if(subtitle_codec_tag)
        subtitle_enc->codec_tag= subtitle_codec_tag;

    if (oc->oformat->flags & AVFMT_GLOBALHEADER) {
        subtitle_enc->flags |= CODEC_FLAG_GLOBAL_HEADER;
    }

    if (subtitle_language) {
        av_dict_set(&st->metadata, "language", subtitle_language, 0);
        av_freep(&subtitle_language);
    }

    subtitle_disable = 0;
    return ost;
}

/* arg format is "output-stream-index:streamid-value". */
static int opt_streamid(const char *opt, const char *arg)
{
    int idx;
    char *p;
    char idx_str[16];

    av_strlcpy(idx_str, arg, sizeof(idx_str));
    p = strchr(idx_str, ':');
    if (!p) {
        fprintf(stderr,
                "Invalid value '%s' for option '%s', required syntax is 'index:value'\n",
                arg, opt);
        exit_program(1);
    }
    *p++ = '\0';
    idx = parse_number_or_die(opt, idx_str, OPT_INT, 0, MAX_STREAMS-1);
    streamid_map = grow_array(streamid_map, sizeof(*streamid_map), &nb_streamid_map, idx+1);
    streamid_map[idx] = parse_number_or_die(opt, p, OPT_INT, 0, INT_MAX);
    return 0;
}
static int read_ffserver_streams(AVFormatContext *s, const char *filename)
{
    int i, err;
    AVFormatContext *ic = NULL;

    err = avformat_open_input(&ic, filename, NULL, NULL);
    if (err < 0)
        return err;
    /* copy stream format */
    for(i=0;i<ic->nb_streams;i++) {
        AVStream *st;
        OutputStream *ost;
        AVCodec *codec;

        codec = avcodec_find_encoder(ic->streams[i]->codec->codec_id);
        ost   = new_output_stream(s, codec->type);
        st    = ost->st;

        // FIXME: a more elegant solution is needed
        memcpy(st, ic->streams[i], sizeof(AVStream));
        st->info = av_malloc(sizeof(*st->info));
        memcpy(st->info, ic->streams[i]->info, sizeof(*st->info));
        avcodec_copy_context(st->codec, ic->streams[i]->codec);

        if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && !st->stream_copy)
            choose_sample_fmt(st, codec);
        else if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && !st->stream_copy)
            choose_pixel_fmt(st, codec);
    }

    av_close_input_file(ic);
    return 0;
}


static int copy_chapters(int infile, int outfile)
{
    AVFormatContext *is = input_files[infile].ctx;
    AVFormatContext *os = output_files[outfile];
    int i;

    for (i = 0; i < is->nb_chapters; i++) {
        AVChapter *in_ch = is->chapters[i], *out_ch;
        int64_t ts_off   = av_rescale_q(start_time - input_files[infile].ts_offset,
                                      AV_TIME_BASE_Q, in_ch->time_base);
        int64_t rt       = (recording_time == INT64_MAX) ? INT64_MAX :
                           av_rescale_q(recording_time, AV_TIME_BASE_Q, in_ch->time_base);


        if (in_ch->end < ts_off)
            continue;
        if (rt != INT64_MAX && in_ch->start > rt + ts_off)
            break;

        out_ch = av_mallocz(sizeof(AVChapter));
        if (!out_ch)
            return AVERROR(ENOMEM);

        out_ch->id        = in_ch->id;
        out_ch->time_base = in_ch->time_base;
        out_ch->start     = FFMAX(0,  in_ch->start - ts_off);
        out_ch->end       = FFMIN(rt, in_ch->end   - ts_off);

        if (metadata_chapters_autocopy)
            av_dict_copy(&out_ch->metadata, in_ch->metadata, 0);

        os->nb_chapters++;
        os->chapters = av_realloc(os->chapters, sizeof(AVChapter)*os->nb_chapters);
        if (!os->chapters)
            return AVERROR(ENOMEM);
        os->chapters[os->nb_chapters - 1] = out_ch;
    }
    return 0;
}

static int opt_output_file(const char *opt, const char *filename)
{
    AVFormatContext *oc;
    int i, err;
    AVOutputFormat *file_oformat;
    OutputStream *ost;
    InputStream  *ist;

    if(nb_output_files >= FF_ARRAY_ELEMS(output_files)){
        fprintf(stderr, "Too many output files\n");
        exit_program(1);
    }

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

    err = avformat_alloc_output_context2(&oc, NULL, last_asked_format, filename);
    last_asked_format = NULL;
    if (!oc) {
        print_error(filename, err);
        exit_program(1);
    }
    file_oformat= oc->oformat;

    if (!strcmp(file_oformat->name, "ffm") &&
        av_strstart(filename, "http:", NULL)) {
        /* special case for files sent to ffserver: we get the stream
           parameters from ffserver */
        int err = read_ffserver_streams(oc, filename);
        if (err < 0) {
            print_error(filename, err);
            exit_program(1);
        }
    } else if (!nb_stream_maps) {
        /* pick the "best" stream of each type */
#define NEW_STREAM(type, index)\
        if (index >= 0) {\
            ost = new_ ## type ## _stream(oc);\
            ost->source_index = index;\
            ost->sync_ist     = &input_streams[index];\
            input_streams[index].discard = 0;\
        }

        /* video: highest resolution */
        if (!video_disable && oc->oformat->video_codec != CODEC_ID_NONE) {
            int area = 0, idx = -1;
            for (i = 0; i < nb_input_streams; i++) {
                ist = &input_streams[i];
                if (ist->st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
                    ist->st->codec->width * ist->st->codec->height > area) {
                    area = ist->st->codec->width * ist->st->codec->height;
                    idx = i;
                }
            }
            NEW_STREAM(video, idx);
        }

        /* audio: most channels */
        if (!audio_disable && oc->oformat->audio_codec != CODEC_ID_NONE) {
            int channels = 0, idx = -1;
            for (i = 0; i < nb_input_streams; i++) {
                ist = &input_streams[i];
                if (ist->st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&
                    ist->st->codec->channels > channels) {
                    channels = ist->st->codec->channels;
                    idx = i;
                }
            }
            NEW_STREAM(audio, idx);
        }

        /* subtitles: pick first */
        if (!subtitle_disable && oc->oformat->subtitle_codec != CODEC_ID_NONE) {
            for (i = 0; i < nb_input_streams; i++)
                if (input_streams[i].st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {
                    NEW_STREAM(subtitle, i);
                    break;
                }
        }
        /* do something with data? */
    } else {
        for (i = 0; i < nb_stream_maps; i++) {
            StreamMap *map = &stream_maps[i];

            if (map->disabled)
                continue;

            ist = &input_streams[input_files[map->file_index].ist_index + map->stream_index];
            switch (ist->st->codec->codec_type) {
            case AVMEDIA_TYPE_VIDEO:    ost = new_video_stream(oc);    break;
            case AVMEDIA_TYPE_AUDIO:    ost = new_audio_stream(oc);    break;
            case AVMEDIA_TYPE_SUBTITLE: ost = new_subtitle_stream(oc); break;
            case AVMEDIA_TYPE_DATA:     ost = new_data_stream(oc);     break;
            default:
                av_log(NULL, AV_LOG_ERROR, "Cannot map stream #%d.%d - unsupported type.\n",
                       map->file_index, map->stream_index);
                exit_program(1);
            }

            ost->source_index = input_files[map->file_index].ist_index + map->stream_index;
            ost->sync_ist = &input_streams[input_files[map->sync_file_index].ist_index +
                                           map->sync_stream_index];
            ist->discard = 0;
        }
    }

    av_dict_copy(&oc->metadata, metadata, 0);
    av_dict_free(&metadata);

    av_dict_copy(&output_opts[nb_output_files], format_opts, 0);
    output_files[nb_output_files++] = oc;

    /* check filename in case of an image number is expected */
    if (oc->oformat->flags & AVFMT_NEEDNUMBER) {
        if (!av_filename_number_test(oc->filename)) {
            print_error(oc->filename, AVERROR(EINVAL));
            exit_program(1);
        }
    }

    if (!(oc->oformat->flags & AVFMT_NOFILE)) {
        /* test if it already exists to avoid loosing precious files */
        if (!file_overwrite &&
            (strchr(filename, ':') == NULL ||
             filename[1] == ':' ||
             av_strstart(filename, "file:", NULL))) {
            if (avio_check(filename, 0) == 0) {
                if (!using_stdin) {
                    fprintf(stderr,"File '%s' already exists. Overwrite ? [y/N] ", filename);
                    fflush(stderr);
                    if (!read_yesno()) {
                        fprintf(stderr, "Not overwriting - exiting\n");
                        exit_program(1);
                    }
                }
                else {
                    fprintf(stderr,"File '%s' already exists. Exiting.\n", filename);
                    exit_program(1);
                }
            }
        }

        /* open the file */
        if ((err = avio_open(&oc->pb, filename, AVIO_FLAG_WRITE)) < 0) {
            print_error(filename, err);
            exit_program(1);
        }
    }

    oc->preload= (int)(mux_preload*AV_TIME_BASE);
    oc->max_delay= (int)(mux_max_delay*AV_TIME_BASE);

    if (loop_output >= 0) {
        av_log(NULL, AV_LOG_WARNING, "-loop_output is deprecated, use -loop\n");
        oc->loop_output = loop_output;
    }

    /* copy chapters */
    if (chapters_input_file >= nb_input_files) {
        if (chapters_input_file == INT_MAX) {
            /* copy chapters from the first input file that has them*/
            chapters_input_file = -1;
            for (i = 0; i < nb_input_files; i++)
                if (input_files[i].ctx->nb_chapters) {
                    chapters_input_file = i;
                    break;
                }
        } else {
            av_log(NULL, AV_LOG_ERROR, "Invalid input file index %d in chapter mapping.\n",
                   chapters_input_file);
            exit_program(1);
        }
    }
    if (chapters_input_file >= 0)
        copy_chapters(chapters_input_file, nb_output_files - 1);

    /* copy metadata */
    for (i = 0; i < nb_meta_data_maps; i++) {
        AVFormatContext *files[2];
        AVDictionary    **meta[2];
        int j;

#define METADATA_CHECK_INDEX(index, nb_elems, desc)\
        if ((index) < 0 || (index) >= (nb_elems)) {\
            av_log(NULL, AV_LOG_ERROR, "Invalid %s index %d while processing metadata maps\n",\
                     (desc), (index));\
            exit_program(1);\
        }

        int in_file_index = meta_data_maps[i][1].file;
        if (in_file_index < 0)
            continue;
        METADATA_CHECK_INDEX(in_file_index, nb_input_files, "input file")

        files[0] = oc;
        files[1] = input_files[in_file_index].ctx;

        for (j = 0; j < 2; j++) {
            MetadataMap *map = &meta_data_maps[i][j];

            switch (map->type) {
            case 'g':
                meta[j] = &files[j]->metadata;
                break;
            case 's':
                METADATA_CHECK_INDEX(map->index, files[j]->nb_streams, "stream")
                meta[j] = &files[j]->streams[map->index]->metadata;
                break;
            case 'c':
                METADATA_CHECK_INDEX(map->index, files[j]->nb_chapters, "chapter")
                meta[j] = &files[j]->chapters[map->index]->metadata;
                break;
            case 'p':
                METADATA_CHECK_INDEX(map->index, files[j]->nb_programs, "program")
                meta[j] = &files[j]->programs[map->index]->metadata;
                break;
            }
        }

        av_dict_copy(meta[0], *meta[1], AV_DICT_DONT_OVERWRITE);
    }

    /* copy global metadata by default */
    if (metadata_global_autocopy && nb_input_files)
        av_dict_copy(&oc->metadata, input_files[0].ctx->metadata,
                     AV_DICT_DONT_OVERWRITE);
    if (metadata_streams_autocopy)
        for (i = 0; i < oc->nb_streams; i++) {
            InputStream *ist = &input_streams[output_streams_for_file[nb_output_files-1][i]->source_index];
            av_dict_copy(&oc->streams[i]->metadata, ist->st->metadata, AV_DICT_DONT_OVERWRITE);
        }

    frame_rate    = (AVRational){0, 0};
    frame_width   = 0;
    frame_height  = 0;
    audio_sample_rate = 0;
    audio_channels    = 0;
    audio_sample_fmt  = AV_SAMPLE_FMT_NONE;
    chapters_input_file = INT_MAX;

    av_freep(&meta_data_maps);
    nb_meta_data_maps = 0;
    metadata_global_autocopy   = 1;
    metadata_streams_autocopy  = 1;
    metadata_chapters_autocopy = 1;
    av_freep(&stream_maps);
    nb_stream_maps = 0;

    av_dict_free(&codec_names);

    av_freep(&forced_key_frames);
    uninit_opts();
    init_opts();
    return 0;
}

/* same option as mencoder */
static int opt_pass(const char *opt, const char *arg)
{
    do_pass = parse_number_or_die(opt, arg, OPT_INT, 1, 2);
    return 0;
}

static int64_t getutime(void)
{
#if HAVE_GETRUSAGE
    struct rusage rusage;

    getrusage(RUSAGE_SELF, &rusage);
    return (rusage.ru_utime.tv_sec * 1000000LL) + rusage.ru_utime.tv_usec;
#elif HAVE_GETPROCESSTIMES
    HANDLE proc;
    FILETIME c, e, k, u;
    proc = GetCurrentProcess();
    GetProcessTimes(proc, &c, &e, &k, &u);
    return ((int64_t) u.dwHighDateTime << 32 | u.dwLowDateTime) / 10;
#else
    return av_gettime();
#endif
}

static int64_t getmaxrss(void)
{
#if HAVE_GETRUSAGE && HAVE_STRUCT_RUSAGE_RU_MAXRSS
    struct rusage rusage;
    getrusage(RUSAGE_SELF, &rusage);
    return (int64_t)rusage.ru_maxrss * 1024;
#elif HAVE_GETPROCESSMEMORYINFO
    HANDLE proc;
    PROCESS_MEMORY_COUNTERS memcounters;
    proc = GetCurrentProcess();
    memcounters.cb = sizeof(memcounters);
    GetProcessMemoryInfo(proc, &memcounters, sizeof(memcounters));
    return memcounters.PeakPagefileUsage;
#else
    return 0;
#endif
}

static void parse_matrix_coeffs(uint16_t *dest, const char *str)
{
    int i;
    const char *p = str;
    for(i = 0;; i++) {
        dest[i] = atoi(p);
        if(i == 63)
            break;
        p = strchr(p, ',');
        if(!p) {
            fprintf(stderr, "Syntax error in matrix \"%s\" at coeff %d\n", str, i);
            exit_program(1);
        }
        p++;
    }
}

static int opt_inter_matrix(const char *opt, const char *arg)
{
    inter_matrix = av_mallocz(sizeof(uint16_t) * 64);
    parse_matrix_coeffs(inter_matrix, arg);
    return 0;
}

static int opt_intra_matrix(const char *opt, const char *arg)
{
    intra_matrix = av_mallocz(sizeof(uint16_t) * 64);
    parse_matrix_coeffs(intra_matrix, arg);
    return 0;
}

static void show_usage(void)
{
    printf("Hyper fast Audio and Video encoder\n");
    printf("usage: %s [options] [[infile options] -i infile]... {[outfile options] outfile}...\n", program_name);
    printf("\n");
}

static int opt_help(const char *opt, const char *arg)
{