Function decode_blocks

libavcodec/alsdec.c:1042–1118

Decodes blocks dependently. */

/** Decodes blocks dependently.
 */
static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
                         unsigned int c, const unsigned int *div_blocks,
                         unsigned int *js_blocks)
{
    ALSSpecificConfig *sconf = &ctx->sconf;
    unsigned int offset = 0;
    unsigned int b;
    ALSBlockData bd[2];

    memset(bd, 0, 2 * sizeof(ALSBlockData));

    bd[0].ra_block         = ra_frame;
    bd[0].use_ltp          = ctx->use_ltp;
    bd[0].ltp_lag          = ctx->ltp_lag;
    bd[0].ltp_gain         = ctx->ltp_gain[0];
    bd[0].quant_cof        = ctx->quant_cof[0];
    bd[0].lpc_cof          = ctx->lpc_cof[0];
    bd[0].prev_raw_samples = ctx->prev_raw_samples;
    bd[0].js_blocks        = *js_blocks;

    bd[1].ra_block         = ra_frame;
    bd[1].use_ltp          = ctx->use_ltp;
    bd[1].ltp_lag          = ctx->ltp_lag;
    bd[1].ltp_gain         = ctx->ltp_gain[0];
    bd[1].quant_cof        = ctx->quant_cof[0];
    bd[1].lpc_cof          = ctx->lpc_cof[0];
    bd[1].prev_raw_samples = ctx->prev_raw_samples;
    bd[1].js_blocks        = *(js_blocks + 1);

    // decode all blocks
    for (b = 0; b < ctx->num_blocks; b++) {
        unsigned int s;

        bd[0].shift_lsbs   = 0;
        bd[1].shift_lsbs   = 0;

        bd[0].block_length = div_blocks[b];
        bd[1].block_length = div_blocks[b];

        bd[0].raw_samples  = ctx->raw_samples[c    ] + offset;
        bd[1].raw_samples  = ctx->raw_samples[c + 1] + offset;

        bd[0].raw_other    = bd[1].raw_samples;
        bd[1].raw_other    = bd[0].raw_samples;

        if(read_decode_block(ctx, &bd[0]) || read_decode_block(ctx, &bd[1])) {
            // damaged block, write zero for the rest of the frame
            zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
            zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
            return -1;
        }

        // reconstruct joint-stereo blocks
        if (bd[0].js_blocks) {
            if (bd[1].js_blocks)
                av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair!\n");

            for (s = 0; s < div_blocks[b]; s++)