Function read_channel_data

libavcodec/alsdec.c:1123–1165

Reads the channel data. */

/** Reads the channel data.
  */
static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
{
    GetBitContext *gb       = &ctx->gb;
    ALSChannelData *current = cd;
    unsigned int channels   = ctx->avctx->channels;
    int entries             = 0;

    while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
        current->master_channel = get_bits_long(gb, av_ceil_log2(channels));

        if (current->master_channel >= channels) {
            av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
            return -1;
        }

        if (current->master_channel != c) {
            current->time_diff_flag = get_bits1(gb);
            current->weighting[0]   = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
            current->weighting[1]   = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 32)];
            current->weighting[2]   = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];

            if (current->time_diff_flag) {
                current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
                current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
                current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];

                current->time_diff_sign  = get_bits1(gb);
                current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
            }
        }

        current++;
        entries++;
    }

    if (entries == channels) {
        av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
        return -1;
    }

    align_get_bits(gb);
    return 0;
}


/** Recursively reverts the inter-channel correlation for a block.