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Diffstat (limited to 'contrib/ffmpeg/libavcodec/ac3.c')
-rw-r--r--contrib/ffmpeg/libavcodec/ac3.c287
1 files changed, 0 insertions, 287 deletions
diff --git a/contrib/ffmpeg/libavcodec/ac3.c b/contrib/ffmpeg/libavcodec/ac3.c
deleted file mode 100644
index 3749d02f0..000000000
--- a/contrib/ffmpeg/libavcodec/ac3.c
+++ /dev/null
@@ -1,287 +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 "ac3tab.h"
-#include "bitstream.h"
-
-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 *bndpsd)
-{
- 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=masktab[start];
- do {
- v=psd[j];
- j++;
- end1 = FFMIN(bndtab[k+1], end);
- for(i=j;i<end1;i++) {
- /* logadd */
- int adr = FFMIN(FFABS(v - psd[j]) >> 1, 255);
- v = FFMAX(v, psd[j]) + latab[adr];
- j++;
- }
- bndpsd[k]=v;
- k++;
- } while (end > bndtab[k]);
-}
-
-void ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *bndpsd,
- int start, int end, int fgain, int is_lfe,
- int deltbae, int deltnseg, uint8_t *deltoffst,
- uint8_t *deltlen, uint8_t *deltba,
- int16_t *mask)
-{
- int16_t excite[50]; /* excitation */
- int bin, k;
- int bndstrt, bndend, begin, end1, tmp;
- int lowcomp, fastleak, slowleak;
-
- /* excitation function */
- bndstrt = masktab[start];
- bndend = masktab[end-1] + 1;
-
- if (bndstrt == 0) {
- lowcomp = 0;
- lowcomp = calc_lowcomp1(lowcomp, bndpsd[0], bndpsd[1], 384);
- excite[0] = bndpsd[0] - fgain - lowcomp;
- lowcomp = calc_lowcomp1(lowcomp, bndpsd[1], bndpsd[2], 384);
- excite[1] = bndpsd[1] - fgain - lowcomp;
- begin = 7;
- for (bin = 2; bin < 7; bin++) {
- if (!(is_lfe && bin == 6))
- lowcomp = calc_lowcomp1(lowcomp, bndpsd[bin], bndpsd[bin+1], 384);
- fastleak = bndpsd[bin] - fgain;
- slowleak = bndpsd[bin] - s->sgain;
- excite[bin] = fastleak - lowcomp;
- if (!(is_lfe && bin == 6)) {
- if (bndpsd[bin] <= bndpsd[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, bndpsd[bin], bndpsd[bin+1], bin);
-
- fastleak = FFMAX(fastleak - s->fdecay, bndpsd[bin] - fgain);
- slowleak = FFMAX(slowleak - s->sdecay, bndpsd[bin] - s->sgain);
- excite[bin] = FFMAX(fastleak - lowcomp, slowleak);
- }
- begin = 22;
- } else {
- /* coupling channel */
- begin = bndstrt;
-
- fastleak = (s->cplfleak << 8) + 768;
- slowleak = (s->cplsleak << 8) + 768;
- }
-
- for (bin = begin; bin < bndend; bin++) {
- fastleak = FFMAX(fastleak - s->fdecay, bndpsd[bin] - fgain);
- slowleak = FFMAX(slowleak - s->sdecay, bndpsd[bin] - s->sgain);
- excite[bin] = FFMAX(fastleak, slowleak);
- }
-
- /* compute masking curve */
-
- for (bin = bndstrt; bin < bndend; bin++) {
- tmp = s->dbknee - bndpsd[bin];
- if (tmp > 0) {
- excite[bin] += tmp >> 2;
- }
- mask[bin] = FFMAX(hth[bin >> s->halfratecod][s->fscod], excite[bin]);
- }
-
- /* delta bit allocation */
-
- if (deltbae == 0 || deltbae == 1) {
- int band, seg, delta;
- band = 0;
- for (seg = 0; seg < deltnseg; seg++) {
- band += deltoffst[seg];
- if (deltba[seg] >= 4) {
- delta = (deltba[seg] - 3) << 7;
- } else {
- delta = (deltba[seg] - 4) << 7;
- }
- for (k = 0; k < deltlen[seg]; k++) {
- mask[band] += delta;
- band++;
- }
- }
- }
-}
-
-void ff_ac3_bit_alloc_calc_bap(int16_t *mask, int16_t *psd, int start, int end,
- int snroffset, int floor, uint8_t *bap)
-{
- int i, j, k, end1, v, address;
-
- /* special case, if snroffset is -960, set all bap's to zero */
- if(snroffset == -960) {
- memset(bap, 0, 256);
- return;
- }
-
- i = start;
- j = masktab[start];
- do {
- v = (FFMAX(mask[j] - snroffset - floor, 0) & 0x1FE0) + floor;
- end1 = FFMIN(bndtab[j] + bndsz[j], end);
- for (k = i; k < end1; k++) {
- address = av_clip((psd[i] - v) >> 5, 0, 63);
- bap[i] = baptab[address];
- i++;
- }
- } while (end > bndtab[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 snroffset, int fgain, int is_lfe,
- int deltbae,int deltnseg,
- uint8_t *deltoffst, uint8_t *deltlen,
- uint8_t *deltba)
-{
- int16_t psd[256]; /* scaled exponents */
- int16_t bndpsd[50]; /* interpolated exponents */
- int16_t mask[50]; /* masking value */
-
- ff_ac3_bit_alloc_calc_psd(exp, start, end, psd, bndpsd);
-
- ff_ac3_bit_alloc_calc_mask(s, bndpsd, start, end, fgain, is_lfe,
- deltbae, deltnseg, deltoffst, deltlen, deltba,
- mask);
-
- ff_ac3_bit_alloc_calc_bap(mask, psd, start, end, snroffset, 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++) {
- bndtab[i] = l;
- v = bndsz[i];
- for(j=0;j<v;j++) masktab[k++]=i;
- l += v;
- }
- bndtab[50] = l;
-}
-
-int ff_ac3_parse_header(const uint8_t buf[7], AC3HeaderInfo *hdr)
-{
- GetBitContext gbc;
-
- memset(hdr, 0, sizeof(*hdr));
-
- init_get_bits(&gbc, buf, 54);
-
- hdr->sync_word = get_bits(&gbc, 16);
- if(hdr->sync_word != 0x0B77)
- return -1;
-
- /* read ahead to bsid to make sure this is AC-3, not E-AC-3 */
- hdr->bsid = show_bits_long(&gbc, 29) & 0x1F;
- if(hdr->bsid > 10)
- return -2;
-
- hdr->crc1 = get_bits(&gbc, 16);
- hdr->fscod = get_bits(&gbc, 2);
- if(hdr->fscod == 3)
- return -3;
-
- hdr->frmsizecod = get_bits(&gbc, 6);
- if(hdr->frmsizecod > 37)
- return -4;
-
- skip_bits(&gbc, 5); // skip bsid, already got it
-
- hdr->bsmod = get_bits(&gbc, 3);
- hdr->acmod = get_bits(&gbc, 3);
- if((hdr->acmod & 1) && hdr->acmod != 1) {
- hdr->cmixlev = get_bits(&gbc, 2);
- }
- if(hdr->acmod & 4) {
- hdr->surmixlev = get_bits(&gbc, 2);
- }
- if(hdr->acmod == 2) {
- hdr->dsurmod = get_bits(&gbc, 2);
- }
- hdr->lfeon = get_bits1(&gbc);
-
- hdr->halfratecod = FFMAX(hdr->bsid, 8) - 8;
- hdr->sample_rate = ff_ac3_freqs[hdr->fscod] >> hdr->halfratecod;
- hdr->bit_rate = (ff_ac3_bitratetab[hdr->frmsizecod>>1] * 1000) >> hdr->halfratecod;
- hdr->channels = ff_ac3_channels[hdr->acmod] + hdr->lfeon;
- hdr->frame_size = ff_ac3_frame_sizes[hdr->frmsizecod][hdr->fscod] * 2;
-
- return 0;
-}
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