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Diffstat (limited to 'contrib/ffmpeg/libavcodec/ac3.c')
-rw-r--r--contrib/ffmpeg/libavcodec/ac3.c239
1 files changed, 0 insertions, 239 deletions
diff --git a/contrib/ffmpeg/libavcodec/ac3.c b/contrib/ffmpeg/libavcodec/ac3.c
deleted file mode 100644
index cc80277bc..000000000
--- a/contrib/ffmpeg/libavcodec/ac3.c
+++ /dev/null
@@ -1,239 +0,0 @@
-/*
- * Common code between AC3 encoder and decoder
- * Copyright (c) 2000 Fabrice Bellard.
- *
- * This file is part of FFmpeg.
- *
- * FFmpeg is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * FFmpeg is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-/**
- * @file ac3.c
- * Common code between AC3 encoder and decoder.
- */
-
-#include "avcodec.h"
-#include "ac3.h"
-#include "bitstream.h"
-
-static uint8_t band_start_tab[51];
-static uint8_t bin_to_band_tab[253];
-
-static inline int calc_lowcomp1(int a, int b0, int b1, int c)
-{
- if ((b0 + 256) == b1) {
- a = c;
- } else if (b0 > b1) {
- a = FFMAX(a - 64, 0);
- }
- return a;
-}
-
-static inline int calc_lowcomp(int a, int b0, int b1, int bin)
-{
- if (bin < 7) {
- return calc_lowcomp1(a, b0, b1, 384);
- } else if (bin < 20) {
- return calc_lowcomp1(a, b0, b1, 320);
- } else {
- return FFMAX(a - 128, 0);
- }
-}
-
-void ff_ac3_bit_alloc_calc_psd(int8_t *exp, int start, int end, int16_t *psd,
- int16_t *band_psd)
-{
- int bin, i, j, k, end1, v;
-
- /* exponent mapping to PSD */
- for(bin=start;bin<end;bin++) {
- psd[bin]=(3072 - (exp[bin] << 7));
- }
-
- /* PSD integration */
- j=start;
- k=bin_to_band_tab[start];
- do {
- v=psd[j];
- j++;
- end1 = FFMIN(band_start_tab[k+1], end);
- for(i=j;i<end1;i++) {
- /* logadd */
- int adr = FFMIN(FFABS(v - psd[j]) >> 1, 255);
- v = FFMAX(v, psd[j]) + ff_ac3_log_add_tab[adr];
- j++;
- }
- band_psd[k]=v;
- k++;
- } while (end > band_start_tab[k]);
-}
-
-void ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *band_psd,
- int start, int end, int fast_gain, int is_lfe,
- int dba_mode, int dba_nsegs, uint8_t *dba_offsets,
- uint8_t *dba_lengths, uint8_t *dba_values,
- int16_t *mask)
-{
- int16_t excite[50]; /* excitation */
- int bin, k;
- int bndstrt, bndend, begin, end1, tmp;
- int lowcomp, fastleak, slowleak;
-
- /* excitation function */
- bndstrt = bin_to_band_tab[start];
- bndend = bin_to_band_tab[end-1] + 1;
-
- if (bndstrt == 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;
- 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);
- }
- begin = 22;
- } else {
- /* coupling channel */
- begin = bndstrt;
-
- 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);
- }
-
- /* compute masking curve */
-
- for (bin = bndstrt; bin < bndend; bin++) {
- tmp = s->db_per_bit - band_psd[bin];
- if (tmp > 0) {
- excite[bin] += tmp >> 2;
- }
- mask[bin] = FFMAX(ff_ac3_hearing_threshold_tab[bin >> s->sr_shift][s->sr_code], excite[bin]);
- }
-
- /* delta bit allocation */
-
- if (dba_mode == DBA_REUSE || dba_mode == DBA_NEW) {
- int band, seg, delta;
- band = 0;
- for (seg = 0; seg < dba_nsegs; seg++) {
- band += dba_offsets[seg];
- if (dba_values[seg] >= 4) {
- delta = (dba_values[seg] - 3) << 7;
- } else {
- delta = (dba_values[seg] - 4) << 7;
- }
- for (k = 0; k < dba_lengths[seg]; k++) {
- mask[band] += delta;
- band++;
- }
- }
- }
-}
-
-void ff_ac3_bit_alloc_calc_bap(int16_t *mask, int16_t *psd, int start, int end,
- int snr_offset, int floor, uint8_t *bap)
-{
- int i, j, k, end1, v, address;
-
- /* special case, if snr offset is -960, set all bap's to zero */
- if(snr_offset == -960) {
- memset(bap, 0, 256);
- return;
- }
-
- i = start;
- j = 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] = ff_ac3_bap_tab[address];
- i++;
- }
- } while (end > band_start_tab[j++]);
-}
-
-/* AC3 bit allocation. The algorithm is the one described in the AC3
- spec. */
-void ac3_parametric_bit_allocation(AC3BitAllocParameters *s, uint8_t *bap,
- int8_t *exp, int start, int end,
- int snr_offset, int fast_gain, int is_lfe,
- int dba_mode, int dba_nsegs,
- uint8_t *dba_offsets, uint8_t *dba_lengths,
- uint8_t *dba_values)
-{
- int16_t psd[256]; /* scaled exponents */
- int16_t band_psd[50]; /* interpolated exponents */
- int16_t mask[50]; /* masking value */
-
- 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);
-
- ff_ac3_bit_alloc_calc_bap(mask, psd, start, end, snr_offset, s->floor, bap);
-}
-
-/**
- * Initializes some tables.
- * note: This function must remain thread safe because it is called by the
- * AVParser init code.
- */
-void ac3_common_init(void)
-{
- 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;
- }
- band_start_tab[50] = l;
-}
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