int mant1_cnt, mant2_cnt, mant4_cnt;
} AC3EncodeContext;
-#include "ac3tab.h"
+static int16_t costab[64];
+static int16_t sintab[64];
+static int16_t fft_rev[512];
+static int16_t xcos1[128];
+static int16_t xsin1[128];
#define MDCT_NBITS 9
#define N (1 << MDCT_NBITS)
return v;
}
-static inline int calc_lowcomp1(int a, int b0, int b1)
-{
- if ((b0 + 256) == b1) {
- a = 384 ;
- } else if (b0 > b1) {
- a = a - 64;
- if (a < 0) a=0;
- }
- return a;
-}
-
-static inline int calc_lowcomp(int a, int b0, int b1, int bin)
-{
- if (bin < 7) {
- if ((b0 + 256) == b1) {
- a = 384 ;
- } else if (b0 > b1) {
- a = a - 64;
- if (a < 0) a=0;
- }
- } else if (bin < 20) {
- if ((b0 + 256) == b1) {
- a = 320 ;
- } else if (b0 > b1) {
- a= a - 64;
- if (a < 0) a=0;
- }
- } else {
- a = a - 128;
- if (a < 0) a=0;
- }
- return a;
-}
-
-/* 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)
-{
- int bin,i,j,k,end1,v,v1,bndstrt,bndend,lowcomp,begin;
- int fastleak,slowleak,address,tmp;
- int16_t psd[256]; /* scaled exponents */
- int16_t bndpsd[50]; /* interpolated exponents */
- int16_t excite[50]; /* excitation */
- int16_t mask[50]; /* masking value */
-
- /* 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=bndtab[k+1];
- if (end1 > end) end1=end;
- for(i=j;i<end1;i++) {
- int c,adr;
- /* logadd */
- v1=psd[j];
- c=v-v1;
- if (c >= 0) {
- adr=c >> 1;
- if (adr > 255) adr=255;
- v=v + latab[adr];
- } else {
- adr=(-c) >> 1;
- if (adr > 255) adr=255;
- v=v1 + latab[adr];
- }
- j++;
- }
- bndpsd[k]=v;
- k++;
- } while (end > bndtab[k]);
-
- /* excitation function */
- bndstrt = masktab[start];
- bndend = masktab[end-1] + 1;
-
- if (bndstrt == 0) {
- lowcomp = 0;
- lowcomp = calc_lowcomp1(lowcomp, bndpsd[0], bndpsd[1]) ;
- excite[0] = bndpsd[0] - fgain - lowcomp ;
- lowcomp = calc_lowcomp1(lowcomp, bndpsd[1], bndpsd[2]) ;
- 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]) ;
- 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 -= s->fdecay ;
- v = bndpsd[bin] - fgain;
- if (fastleak < v) fastleak = v;
-
- slowleak -= s->sdecay ;
- v = bndpsd[bin] - s->sgain;
- if (slowleak < v) slowleak = v;
-
- v=fastleak - lowcomp;
- if (slowleak > v) v=slowleak;
-
- excite[bin] = v;
- }
- begin = 22;
- } else {
- /* coupling channel */
- begin = bndstrt;
-
- fastleak = (s->cplfleak << 8) + 768;
- slowleak = (s->cplsleak << 8) + 768;
- }
-
- for (bin = begin; bin < bndend; bin++) {
- fastleak -= s->fdecay ;
- v = bndpsd[bin] - fgain;
- if (fastleak < v) fastleak = v;
- slowleak -= s->sdecay ;
- v = bndpsd[bin] - s->sgain;
- if (slowleak < v) slowleak = v;
-
- v=fastleak;
- if (slowleak > v) v = slowleak;
- excite[bin] = v;
- }
-
- /* compute masking curve */
-
- for (bin = bndstrt; bin < bndend; bin++) {
- v1 = excite[bin];
- tmp = s->dbknee - bndpsd[bin];
- if (tmp > 0) {
- v1 += tmp >> 2;
- }
- v=hth[bin >> s->halfratecod][s->fscod];
- if (v1 > v) v=v1;
- mask[bin] = v;
- }
-
- /* 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++ ;
- }
- }
- }
-
- /* compute bit allocation */
-
- i = start ;
- j = masktab[start] ;
- do {
- v=mask[j];
- v -= snroffset ;
- v -= s->floor ;
- if (v < 0) v = 0;
- v &= 0x1fe0 ;
- v += s->floor ;
-
- end1=bndtab[j] + bndsz[j];
- if (end1 > end) end1=end;
-
- for (k = i; k < end1; k++) {
- address = (psd[i] - v) >> 5 ;
- if (address < 0) address=0;
- else if (address > 63) address=63;
- bap[i] = baptab[address];
- i++;
- }
- } while (end > bndtab[j++]) ;
-}
-
typedef struct IComplex {
short re,im;
} IComplex;
}
+static void bit_alloc_masking(AC3EncodeContext *s,
+ uint8_t encoded_exp[NB_BLOCKS][AC3_MAX_CHANNELS][N/2],
+ uint8_t exp_strategy[NB_BLOCKS][AC3_MAX_CHANNELS],
+ int16_t psd[NB_BLOCKS][AC3_MAX_CHANNELS][N/2],
+ int16_t mask[NB_BLOCKS][AC3_MAX_CHANNELS][50])
+{
+ int blk, ch;
+ int16_t bndpsd[NB_BLOCKS][AC3_MAX_CHANNELS][50];
+
+ for(blk=0; blk<NB_BLOCKS; blk++) {
+ for(ch=0;ch<s->nb_all_channels;ch++) {
+ if(exp_strategy[blk][ch] == EXP_REUSE) {
+ memcpy(psd[blk][ch], psd[blk-1][ch], (N/2)*sizeof(int16_t));
+ memcpy(mask[blk][ch], mask[blk-1][ch], 50*sizeof(int16_t));
+ } else {
+ ff_ac3_bit_alloc_calc_psd(encoded_exp[blk][ch], 0,
+ s->nb_coefs[ch],
+ psd[blk][ch], bndpsd[blk][ch]);
+ ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, bndpsd[blk][ch],
+ 0, s->nb_coefs[ch],
+ ff_fgaintab[s->fgaincod[ch]],
+ ch == s->lfe_channel,
+ DBA_NONE, 0, NULL, NULL, NULL,
+ mask[blk][ch]);
+ }
+ }
+ }
+}
+
static int bit_alloc(AC3EncodeContext *s,
+ int16_t mask[NB_BLOCKS][AC3_MAX_CHANNELS][50],
+ int16_t psd[NB_BLOCKS][AC3_MAX_CHANNELS][N/2],
uint8_t bap[NB_BLOCKS][AC3_MAX_CHANNELS][N/2],
- uint8_t encoded_exp[NB_BLOCKS][AC3_MAX_CHANNELS][N/2],
- uint8_t exp_strategy[NB_BLOCKS][AC3_MAX_CHANNELS],
int frame_bits, int csnroffst, int fsnroffst)
{
int i, ch;
+ int snroffset;
+
+ snroffset = (((csnroffst - 15) << 4) + fsnroffst) << 2;
/* compute size */
for(i=0;i<NB_BLOCKS;i++) {
s->mant2_cnt = 0;
s->mant4_cnt = 0;
for(ch=0;ch<s->nb_all_channels;ch++) {
- ac3_parametric_bit_allocation(&s->bit_alloc,
- bap[i][ch], (int8_t *)encoded_exp[i][ch],
- 0, s->nb_coefs[ch],
- (((csnroffst-15) << 4) +
- fsnroffst) << 2,
- fgaintab[s->fgaincod[ch]],
- ch == s->lfe_channel,
- 2, 0, NULL, NULL, NULL);
+ ff_ac3_bit_alloc_calc_bap(mask[i][ch], psd[i][ch], 0,
+ s->nb_coefs[ch], snroffset,
+ s->bit_alloc.floor, bap[i][ch]);
frame_bits += compute_mantissa_size(s, bap[i][ch],
s->nb_coefs[ch]);
}
int i, ch;
int csnroffst, fsnroffst;
uint8_t bap1[NB_BLOCKS][AC3_MAX_CHANNELS][N/2];
+ int16_t psd[NB_BLOCKS][AC3_MAX_CHANNELS][N/2];
+ int16_t mask[NB_BLOCKS][AC3_MAX_CHANNELS][50];
static int frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
/* init default parameters */
/* compute real values */
s->bit_alloc.fscod = s->fscod;
s->bit_alloc.halfratecod = s->halfratecod;
- s->bit_alloc.sdecay = sdecaytab[s->sdecaycod] >> s->halfratecod;
- s->bit_alloc.fdecay = fdecaytab[s->fdecaycod] >> s->halfratecod;
- s->bit_alloc.sgain = sgaintab[s->sgaincod];
- s->bit_alloc.dbknee = dbkneetab[s->dbkneecod];
- s->bit_alloc.floor = floortab[s->floorcod];
+ s->bit_alloc.sdecay = ff_sdecaytab[s->sdecaycod] >> s->halfratecod;
+ s->bit_alloc.fdecay = ff_fdecaytab[s->fdecaycod] >> s->halfratecod;
+ s->bit_alloc.sgain = ff_sgaintab[s->sgaincod];
+ s->bit_alloc.dbknee = ff_dbkneetab[s->dbkneecod];
+ s->bit_alloc.floor = ff_floortab[s->floorcod];
/* header size */
frame_bits += 65;
/* audio blocks */
for(i=0;i<NB_BLOCKS;i++) {
frame_bits += s->nb_channels * 2 + 2; /* blksw * c, dithflag * c, dynrnge, cplstre */
- if (s->acmod == 2) {
+ if (s->acmod == AC3_ACMOD_STEREO) {
frame_bits++; /* rematstr */
if(i==0) frame_bits += 4;
}
/* CRC */
frame_bits += 16;
+ /* calculate psd and masking curve before doing bit allocation */
+ bit_alloc_masking(s, encoded_exp, exp_strategy, psd, mask);
+
/* now the big work begins : do the bit allocation. Modify the snr
offset until we can pack everything in the requested frame size */
csnroffst = s->csnroffst;
while (csnroffst >= 0 &&
- bit_alloc(s, bap, encoded_exp, exp_strategy, frame_bits, csnroffst, 0) < 0)
+ bit_alloc(s, mask, psd, bap, frame_bits, csnroffst, 0) < 0)
csnroffst -= SNR_INC1;
if (csnroffst < 0) {
av_log(NULL, AV_LOG_ERROR, "Bit allocation failed, try increasing the bitrate, -ab 384 for example!\n");
return -1;
}
while ((csnroffst + SNR_INC1) <= 63 &&
- bit_alloc(s, bap1, encoded_exp, exp_strategy, frame_bits,
+ bit_alloc(s, mask, psd, bap1, frame_bits,
csnroffst + SNR_INC1, 0) >= 0) {
csnroffst += SNR_INC1;
memcpy(bap, bap1, sizeof(bap1));
}
while ((csnroffst + 1) <= 63 &&
- bit_alloc(s, bap1, encoded_exp, exp_strategy, frame_bits, csnroffst + 1, 0) >= 0) {
+ bit_alloc(s, mask, psd, bap1, frame_bits, csnroffst + 1, 0) >= 0) {
csnroffst++;
memcpy(bap, bap1, sizeof(bap1));
}
fsnroffst = 0;
while ((fsnroffst + SNR_INC1) <= 15 &&
- bit_alloc(s, bap1, encoded_exp, exp_strategy, frame_bits,
+ bit_alloc(s, mask, psd, bap1, frame_bits,
csnroffst, fsnroffst + SNR_INC1) >= 0) {
fsnroffst += SNR_INC1;
memcpy(bap, bap1, sizeof(bap1));
}
while ((fsnroffst + 1) <= 15 &&
- bit_alloc(s, bap1, encoded_exp, exp_strategy, frame_bits,
+ bit_alloc(s, mask, psd, bap1, frame_bits,
csnroffst, fsnroffst + 1) >= 0) {
fsnroffst++;
memcpy(bap, bap1, sizeof(bap1));
return 0;
}
-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;
-}
-
-
static int AC3_encode_init(AVCodecContext *avctx)
{
int freq = avctx->sample_rate;
avctx->frame_size = AC3_FRAME_SIZE;
+ ac3_common_init();
+
/* number of channels */
if (channels < 1 || channels > 6)
return -1;
/* frequency */
for(i=0;i<3;i++) {
for(j=0;j<3;j++)
- if ((ac3_freqs[j] >> i) == freq)
+ if ((ff_ac3_freqs[j] >> i) == freq)
goto found;
}
return -1;
/* bitrate & frame size */
bitrate /= 1000;
for(i=0;i<19;i++) {
- if ((ac3_bitratetab[i] >> s->halfratecod) == bitrate)
+ if ((ff_ac3_bitratetab[i] >> s->halfratecod) == bitrate)
break;
}
if (i == 19)
return -1;
s->bit_rate = bitrate;
s->frmsizecod = i << 1;
- s->frame_size_min = (bitrate * 1000 * AC3_FRAME_SIZE) / (freq * 16);
+ s->frame_size_min = ff_ac3_frame_sizes[s->frmsizecod][s->fscod];
s->bits_written = 0;
s->samples_written = 0;
s->frame_size = s->frame_size_min;
/* initial snr offset */
s->csnroffst = 40;
- ac3_common_init();
-
/* mdct init */
fft_init(MDCT_NBITS - 2);
for(i=0;i<N/4;i++) {
put_bits(&s->pb, 5, s->bsid);
put_bits(&s->pb, 3, s->bsmod);
put_bits(&s->pb, 3, s->acmod);
- if ((s->acmod & 0x01) && s->acmod != 0x01)
+ if ((s->acmod & 0x01) && s->acmod != AC3_ACMOD_MONO)
put_bits(&s->pb, 2, 1); /* XXX -4.5 dB */
if (s->acmod & 0x04)
put_bits(&s->pb, 2, 1); /* XXX -6 dB */
- if (s->acmod == 0x02)
+ if (s->acmod == AC3_ACMOD_STEREO)
put_bits(&s->pb, 2, 0); /* surround not indicated */
put_bits(&s->pb, 1, s->lfe); /* LFE */
put_bits(&s->pb, 5, 31); /* dialog norm: -31 db */
put_bits(&s->pb, 1, 0); /* no new coupling strategy */
}
- if (s->acmod == 2)
+ if (s->acmod == AC3_ACMOD_STEREO)
{
if(block_num==0)
{
/* XXX: could precompute crc_inv */
crc_inv = pow_poly((CRC16_POLY >> 1), (16 * frame_size_58) - 16, CRC16_POLY);
crc1 = mul_poly(crc_inv, crc1, CRC16_POLY);
- frame[2] = crc1 >> 8;
- frame[3] = crc1;
+ AV_WB16(frame+2,crc1);
crc2 = bswap_16(av_crc(av_crc8005, 0, frame + 2 * frame_size_58, (frame_size - frame_size_58) * 2 - 2));
- frame[2*frame_size - 2] = crc2 >> 8;
- frame[2*frame_size - 1] = crc2;
+ AV_WB16(frame+2*frame_size-2,crc2);
// printf("n=%d frame_size=%d\n", n, frame_size);
return frame_size * 2;
/* apply the MDCT window */
for(j=0;j<N/2;j++) {
input_samples[j] = MUL16(input_samples[j],
- ac3_window[j]) >> 15;
+ ff_ac3_window[j]) >> 15;
input_samples[N-j-1] = MUL16(input_samples[N-j-1],
- ac3_window[j]) >> 15;
+ ff_ac3_window[j]) >> 15;
}
/* Normalize the samples to use the maximum available
projects / ffmpeg / blobdiff