int bin, band;
/* exponent mapping to PSD */
- for(bin=start;bin<end;bin++) {
+ for (bin = start; bin < end; bin++) {
psd[bin]=(3072 - (exp[bin] << 7));
}
int v = psd[bin++];
int band_end = FFMIN(band_start_tab[band+1], end);
for (; bin < band_end; bin++) {
+ int max = FFMAX(v, psd[bin]);
/* logadd */
- int adr = FFMIN(FFABS(v - psd[bin]) >> 1, 255);
- v = FFMAX(v, psd[bin]) + ff_ac3_log_add_tab[adr];
+ int adr = FFMIN(max - ((v + psd[bin] + 1) >> 1), 255);
+ v = max + ff_ac3_log_add_tab[adr];
}
band_psd[band++] = v;
} while (end > band_start_tab[band]);
int16_t *mask)
{
int16_t excite[50]; /* excitation */
- int bin, k;
- int bndstrt, bndend, begin, end1, tmp;
+ int band;
+ int band_start, band_end, begin, end1;
int lowcomp, fastleak, slowleak;
/* excitation function */
- bndstrt = bin_to_band_tab[start];
- bndend = bin_to_band_tab[end-1] + 1;
+ band_start = bin_to_band_tab[start];
+ band_end = bin_to_band_tab[end-1] + 1;
- if (bndstrt == 0) {
+ if (band_start == 0) {
lowcomp = 0;
lowcomp = calc_lowcomp1(lowcomp, band_psd[0], band_psd[1], 384);
excite[0] = band_psd[0] - fast_gain - lowcomp;
lowcomp = calc_lowcomp1(lowcomp, band_psd[1], band_psd[2], 384);
excite[1] = band_psd[1] - fast_gain - lowcomp;
begin = 7;
- for (bin = 2; bin < 7; bin++) {
- if (!(is_lfe && bin == 6))
- lowcomp = calc_lowcomp1(lowcomp, band_psd[bin], band_psd[bin+1], 384);
- fastleak = band_psd[bin] - fast_gain;
- slowleak = band_psd[bin] - s->slow_gain;
- excite[bin] = fastleak - lowcomp;
- if (!(is_lfe && bin == 6)) {
- if (band_psd[bin] <= band_psd[bin+1]) {
- begin = bin + 1;
+ for (band = 2; band < 7; band++) {
+ if (!(is_lfe && band == 6))
+ lowcomp = calc_lowcomp1(lowcomp, band_psd[band], band_psd[band+1], 384);
+ fastleak = band_psd[band] - fast_gain;
+ slowleak = band_psd[band] - s->slow_gain;
+ excite[band] = fastleak - lowcomp;
+ if (!(is_lfe && band == 6)) {
+ if (band_psd[band] <= band_psd[band+1]) {
+ begin = band + 1;
break;
}
}
}
- end1=bndend;
- if (end1 > 22) end1=22;
-
- for (bin = begin; bin < end1; bin++) {
- if (!(is_lfe && bin == 6))
- lowcomp = calc_lowcomp(lowcomp, band_psd[bin], band_psd[bin+1], bin);
-
- fastleak = FFMAX(fastleak - s->fast_decay, band_psd[bin] - fast_gain);
- slowleak = FFMAX(slowleak - s->slow_decay, band_psd[bin] - s->slow_gain);
- excite[bin] = FFMAX(fastleak - lowcomp, slowleak);
+ end1 = FFMIN(band_end, 22);
+ for (band = begin; band < end1; band++) {
+ if (!(is_lfe && band == 6))
+ lowcomp = calc_lowcomp(lowcomp, band_psd[band], band_psd[band+1], band);
+ fastleak = FFMAX(fastleak - s->fast_decay, band_psd[band] - fast_gain);
+ slowleak = FFMAX(slowleak - s->slow_decay, band_psd[band] - s->slow_gain);
+ excite[band] = FFMAX(fastleak - lowcomp, slowleak);
}
begin = 22;
} else {
/* coupling channel */
- begin = bndstrt;
-
+ begin = band_start;
fastleak = (s->cpl_fast_leak << 8) + 768;
slowleak = (s->cpl_slow_leak << 8) + 768;
}
- for (bin = begin; bin < bndend; bin++) {
- fastleak = FFMAX(fastleak - s->fast_decay, band_psd[bin] - fast_gain);
- slowleak = FFMAX(slowleak - s->slow_decay, band_psd[bin] - s->slow_gain);
- excite[bin] = FFMAX(fastleak, slowleak);
+ for (band = begin; band < band_end; band++) {
+ fastleak = FFMAX(fastleak - s->fast_decay, band_psd[band] - fast_gain);
+ slowleak = FFMAX(slowleak - s->slow_decay, band_psd[band] - s->slow_gain);
+ excite[band] = FFMAX(fastleak, slowleak);
}
/* compute masking curve */
- for (bin = bndstrt; bin < bndend; bin++) {
- tmp = s->db_per_bit - band_psd[bin];
+ for (band = band_start; band < band_end; band++) {
+ int tmp = s->db_per_bit - band_psd[band];
if (tmp > 0) {
- excite[bin] += tmp >> 2;
+ excite[band] += tmp >> 2;
}
- mask[bin] = FFMAX(ff_ac3_hearing_threshold_tab[bin >> s->sr_shift][s->sr_code], excite[bin]);
+ mask[band] = FFMAX(ff_ac3_hearing_threshold_tab[band >> s->sr_shift][s->sr_code], excite[band]);
}
/* delta bit allocation */
if (dba_mode == DBA_REUSE || dba_mode == DBA_NEW) {
- int band, seg, delta;
+ int i, seg, delta;
if (dba_nsegs >= 8)
return -1;
band = 0;
} else {
delta = (dba_values[seg] - 4) << 7;
}
- for (k = 0; k < dba_lengths[seg]; k++) {
- mask[band] += delta;
- band++;
+ for (i = 0; i < dba_lengths[seg]; i++) {
+ mask[band++] += delta;
}
}
}
int snr_offset, int floor,
const uint8_t *bap_tab, uint8_t *bap)
{
- int i, j, k, end1, v, address;
+ int bin, band;
/* special case, if snr offset is -960, set all bap's to zero */
- if(snr_offset == -960) {
+ if (snr_offset == -960) {
memset(bap, 0, 256);
return;
}
- i = start;
- j = bin_to_band_tab[start];
+ bin = start;
+ band = bin_to_band_tab[start];
do {
- v = (FFMAX(mask[j] - snr_offset - floor, 0) & 0x1FE0) + floor;
- end1 = FFMIN(band_start_tab[j] + ff_ac3_critical_band_size_tab[j], end);
- for (k = i; k < end1; k++) {
- address = av_clip((psd[i] - v) >> 5, 0, 63);
- bap[i] = bap_tab[address];
- i++;
+ int m = (FFMAX(mask[band] - snr_offset - floor, 0) & 0x1FE0) + floor;
+ int band_end = FFMIN(band_start_tab[band+1], end);
+ for (; bin < band_end; bin++) {
+ int address = av_clip((psd[bin] - m) >> 5, 0, 63);
+ bap[bin] = bap_tab[address];
}
- } while (end > band_start_tab[j++]);
+ } while (end > band_start_tab[band++]);
}
/* AC-3 bit allocation. The algorithm is the one described in the AC-3
ff_ac3_bit_alloc_calc_psd(exp, start, end, psd, band_psd);
ff_ac3_bit_alloc_calc_mask(s, band_psd, start, end, fast_gain, is_lfe,
- dba_mode, dba_nsegs, dba_offsets, dba_lengths, dba_values,
- mask);
+ dba_mode, dba_nsegs, dba_offsets, dba_lengths,
+ dba_values, mask);
ff_ac3_bit_alloc_calc_bap(mask, psd, start, end, snr_offset, s->floor,
ff_ac3_bap_tab, bap);
av_cold void ac3_common_init(void)
{
#if !CONFIG_HARDCODED_TABLES
- int i, j, k, l, v;
/* compute bndtab and masktab from bandsz */
- k = 0;
- l = 0;
- for(i=0;i<50;i++) {
- band_start_tab[i] = l;
- v = ff_ac3_critical_band_size_tab[i];
- for(j=0;j<v;j++) bin_to_band_tab[k++]=i;
- l += v;
+ int bin = 0, band;
+ for (band = 0; band < 50; band++) {
+ int band_end = bin + ff_ac3_critical_band_size_tab[band];
+ band_start_tab[band] = bin;
+ while (bin < band_end)
+ bin_to_band_tab[bin++] = band;
}
- band_start_tab[50] = l;
+ band_start_tab[50] = bin;
#endif /* !CONFIG_HARDCODED_TABLES */
}
projects / ffmpeg / blobdiff