Function dca_subsubframe

libavcodec/dca.c:910–1072

static const uint8_t abits_levels[7] = { 3, 5, 7, 9, 13, 17, 25 };

static int dca_subsubframe(DCAContext * s)
{
    int k, l;
    int subsubframe = s->current_subsubframe;

    const float *quant_step_table;

    /* FIXME */
    LOCAL_ALIGNED_16(float, subband_samples, [DCA_PRIM_CHANNELS_MAX], [DCA_SUBBANDS][8]);
    LOCAL_ALIGNED_16(int, block, [8]);

    /*
     * Audio data
     */

    /* Select quantization step size table */
    if (s->bit_rate_index == 0x1f)
        quant_step_table = lossless_quant_d;
    else
        quant_step_table = lossy_quant_d;

    for (k = 0; k < s->prim_channels; k++) {
        for (l = 0; l < s->vq_start_subband[k]; l++) {
            int m;

            /* Select the mid-tread linear quantizer */
            int abits = s->bitalloc[k][l];

            float quant_step_size = quant_step_table[abits];

            /*
             * Determine quantization index code book and its type
             */

            /* Select quantization index code book */
            int sel = s->quant_index_huffman[k][abits];

            /*
             * Extract bits from the bit stream
             */
            if(!abits){
                memset(subband_samples[k][l], 0, 8 * sizeof(subband_samples[0][0][0]));
            } else {
                /* Deal with transients */
                int sfi = s->transition_mode[k][l] && subsubframe >= s->transition_mode[k][l];
                float rscale = quant_step_size * s->scale_factor[k][l][sfi] * s->scalefactor_adj[k][sel];

                if(abits >= 11 || !dca_smpl_bitalloc[abits].vlc[sel].table){
                    if(abits <= 7){
                        /* Block code */
                        int block_code1, block_code2, size, levels;

                        size = abits_sizes[abits-1];
                        levels = abits_levels[abits-1];

                        block_code1 = get_bits(&s->gb, size);
                        /* FIXME Should test return value */
                        decode_blockcode(block_code1, levels, block);