Esempio n. 1
0
static int get_high_utility_cell(elbg_data *elbg)
{
    int i=0;
    /* Using linear search, do binary if it ever turns to be speed critical */
    int r = av_random(elbg->rand_state)%elbg->utility_inc[elbg->numCB-1];
    while (elbg->utility_inc[i] < r)
        i++;
    return i;
}
Esempio n. 2
0
static void nelly_decode_block(NellyMoserDecodeContext *s,
                               const unsigned char block[NELLY_BLOCK_LEN],
                               float audio[NELLY_SAMPLES])
{
    int i,j;
    float buf[NELLY_FILL_LEN], pows[NELLY_FILL_LEN];
    float *aptr, *bptr, *pptr, val, pval;
    int bits[NELLY_BUF_LEN];
    unsigned char v;

    init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8);

    bptr = buf;
    pptr = pows;
    val = ff_nelly_init_table[get_bits(&s->gb, 6)];
    for (i=0 ; i<NELLY_BANDS ; i++) {
        if (i > 0)
            val += ff_nelly_delta_table[get_bits(&s->gb, 5)];
        pval = -pow(2, val/2048) * s->scale_bias;
        for (j = 0; j < ff_nelly_band_sizes_table[i]; j++) {
            *bptr++ = val;
            *pptr++ = pval;
        }

    }

    ff_nelly_get_sample_bits(buf, bits);

    for (i = 0; i < 2; i++) {
        aptr = audio + i * NELLY_BUF_LEN;

        init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8);
        skip_bits(&s->gb, NELLY_HEADER_BITS + i*NELLY_DETAIL_BITS);

        for (j = 0; j < NELLY_FILL_LEN; j++) {
            if (bits[j] <= 0) {
                aptr[j] = M_SQRT1_2*pows[j];
                if (av_random(&s->random_state) & 1)
                    aptr[j] *= -1.0;
            } else {
                v = get_bits(&s->gb, bits[j]);
                aptr[j] = ff_nelly_dequantization_table[(1<<bits[j])-1+v]*pows[j];
            }
        }
        memset(&aptr[NELLY_FILL_LEN], 0,
               (NELLY_BUF_LEN - NELLY_FILL_LEN) * sizeof(float));

        s->imdct_ctx.fft.imdct_calc(&s->imdct_ctx, s->imdct_out,
                                    aptr, s->imdct_tmp);
        /* XXX: overlapping and windowing should be part of a more
           generic imdct function */
        overlap_and_window(s, s->state, aptr, s->imdct_out);
    }
}
Esempio n. 3
0
static void scalar_dequant_float(COOKContext *q, int index, int quant_index,
                           int* subband_coef_index, int* subband_coef_sign,
                           float* mlt_p){
    int i;
    float f1;

    for(i=0 ; i<SUBBAND_SIZE ; i++) {
        if (subband_coef_index[i]) {
            f1 = quant_centroid_tab[index][subband_coef_index[i]];
            if (subband_coef_sign[i]) f1 = -f1;
        } else {
            /* noise coding if subband_coef_index[i] == 0 */
            f1 = dither_tab[index];
            if (av_random(&q->random_state) < 0x80000000) f1 = -f1;
        }
        mlt_p[i] = f1 * rootpow2tab[quant_index+63];
    }
}
Esempio n. 4
0
static int rtp_write_header(AVFormatContext *s1)
{
    RTPMuxContext *s = s1->priv_data;
    int payload_type, max_packet_size, n;
    AVStream *st;

    if (s1->nb_streams != 1)
        return -1;
    st = s1->streams[0];

    payload_type = ff_rtp_get_payload_type(st->codec);
    if (payload_type < 0)
        payload_type = RTP_PT_PRIVATE; /* private payload type */
    if (s1->rtp_pt > 0)
        payload_type = s1->rtp_pt; /* private payload type */
    s->payload_type = payload_type;

// following 2 FIXMEs could be set based on the current time, there is normally no info leak, as RTP will likely be transmitted immediately
    if (random_state.index == 0)
        av_init_random(av_gettime() + (getpid() << 16), &random_state);
    //s->base_timestamp = 0; /* FIXME: was random(), what should this be? */
    s->base_timestamp = av_random(&random_state);
    s->timestamp = s->base_timestamp;
    s->cur_timestamp = 0;
    //s->ssrc = 0; /* FIXME: was random(), what should this be? */
    s->ssrc = av_random(&random_state);
    s->first_packet = 1;
    s->first_rtcp_ntp_time = AV_NOPTS_VALUE;

    max_packet_size = url_fget_max_packet_size(s1->pb);
    if (max_packet_size <= 12)
        return AVERROR(EIO);
    s->buf = av_malloc(max_packet_size);
    if (s->buf == NULL) {
        return AVERROR(ENOMEM);
    }
    s->max_payload_size = max_packet_size - 12;

    s->max_frames_per_packet = 0;
    if (s1->max_delay) {
        if (st->codec->codec_type == CODEC_TYPE_AUDIO) {
            if (st->codec->frame_size == 0) {
                av_log(s1, AV_LOG_ERROR, "Cannot respect max delay: frame size = 0\n");
            } else {
                s->max_frames_per_packet = av_rescale_rnd(s1->max_delay, st->codec->sample_rate, AV_TIME_BASE * st->codec->frame_size, AV_ROUND_DOWN);
            }
        }
        if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
            /* FIXME: We should round down here... */
            s->max_frames_per_packet = av_rescale_q(s1->max_delay, (AVRational){1, 1000000}, st->codec->time_base);
        }
    }

    av_set_pts_info(st, 32, 1, 90000);
    switch(st->codec->codec_id) {
    case CODEC_ID_MP2:
    case CODEC_ID_MP3:
        s->buf_ptr = s->buf + 4;
        break;
    case CODEC_ID_MPEG1VIDEO:
    case CODEC_ID_MPEG2VIDEO:
        break;
    case CODEC_ID_MPEG2TS:
        n = s->max_payload_size / TS_PACKET_SIZE;
        if (n < 1)
            n = 1;
        s->max_payload_size = n * TS_PACKET_SIZE;
        s->buf_ptr = s->buf;
        break;
    case CODEC_ID_AAC:
        s->num_frames = 0;
    default:
        if (st->codec->codec_type == CODEC_TYPE_AUDIO) {
            av_set_pts_info(st, 32, 1, st->codec->sample_rate);
        }
        s->buf_ptr = s->buf;
        break;
    }

    memset(s->stock_buf, 0, sizeof(s->stock_buf));
    s->stock_len = 0;

    return 0;
}