* Decode the grouped exponents according to exponent strategy.
* reference: Section 7.1.3 Exponent Decoding
*/
-static void decode_exponents(GetBitContext *gbc, int exp_strategy, int ngrps,
+static int decode_exponents(GetBitContext *gbc, int exp_strategy, int ngrps,
uint8_t absexp, int8_t *dexps)
{
int i, j, grp, group_size;
/* convert to absolute exps and expand groups */
prevexp = absexp;
for(i=0; i<ngrps*3; i++) {
- prevexp = av_clip(prevexp + dexp[i]-2, 0, 24);
+ prevexp += dexp[i] - 2;
+ if (prevexp < 0 || prevexp > 24)
+ return -1;
for(j=0; j<group_size; j++) {
dexps[(i*group_size)+j] = prevexp;
}
}
+ return 0;
}
/**
for (ch = !cpl_in_use; ch <= s->channels; ch++) {
if (s->exp_strategy[blk][ch] != EXP_REUSE) {
s->dexps[ch][0] = get_bits(gbc, 4) << !ch;
- decode_exponents(gbc, s->exp_strategy[blk][ch],
+ if (decode_exponents(gbc, s->exp_strategy[blk][ch],
s->num_exp_groups[ch], s->dexps[ch][0],
- &s->dexps[ch][s->start_freq[ch]+!!ch]);
+ &s->dexps[ch][s->start_freq[ch]+!!ch])) {
+ av_log(s->avctx, AV_LOG_ERROR, "exponent out-of-range\n");
+ return -1;
+ }
if(ch != CPL_CH && ch != s->lfe_ch)
skip_bits(gbc, 2); /* skip gainrng */
}