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cosmetics: pretty-printing, alignment, etc...

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Originally committed as revision 25958 to svn://svn.ffmpeg.org/ffmpeg/trunk
oldabi
Justin Ruggles 14 years ago
parent a913b5cf60
commit 6a988808a4
1 changed files with 206 additions and 244 deletions
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  1. 450
      libavcodec/ac3enc.c

450
libavcodec/ac3enc.c
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@ -23,6 +23,7 @@
* @file
* The simplest AC-3 encoder.
*/
//#define DEBUG
#include "libavcore/audioconvert.h"
@ -84,9 +85,6 @@ static int16_t xsin1[128];
#define MDCT_NBITS 9
#define MDCT_SAMPLES (1 << MDCT_NBITS)
/* new exponents are sent if their Norm 1 exceed this number */
#define EXP_DIFF_THRESHOLD 1000
#define FIX15(a) av_clip_int16(SCALE_FLOAT(a, 15))
typedef struct IComplex {
@ -100,8 +98,8 @@ static av_cold void fft_init(int ln)
n = 1 << ln;
for(i=0;i<(n/2);i++) {
alpha = 2 * M_PI * (float)i / (float)n;
for (i = 0; i < n/2; i++) {
alpha = 2 * M_PI * (float)i / (float)n;
costab[i] = FIX15(cos(alpha));
sintab[i] = FIX15(sin(alpha));
}
@ -116,46 +114,46 @@ static av_cold void mdct_init(int nbits)
fft_init(nbits - 2);
for(i=0;i<n4;i++) {
alpha = 2 * M_PI * (i + 1.0 / 8.0) / n;
for (i = 0; i < n4; i++) {
alpha = 2 * M_PI * (i + 1.0 / 8.0) / n;
xcos1[i] = FIX15(-cos(alpha));
xsin1[i] = FIX15(-sin(alpha));
}
}
/* butter fly op */
#define BF(pre, pim, qre, qim, pre1, pim1, qre1, qim1) \
{\
int ax, ay, bx, by;\
bx=pre1;\
by=pim1;\
ax=qre1;\
ay=qim1;\
pre = (bx + ax) >> 1;\
pim = (by + ay) >> 1;\
qre = (bx - ax) >> 1;\
qim = (by - ay) >> 1;\
#define BF(pre, pim, qre, qim, pre1, pim1, qre1, qim1) \
{ \
int ax, ay, bx, by; \
bx = pre1; \
by = pim1; \
ax = qre1; \
ay = qim1; \
pre = (bx + ax) >> 1; \
pim = (by + ay) >> 1; \
qre = (bx - ax) >> 1; \
qim = (by - ay) >> 1; \
}
#define CMUL(pre, pim, are, aim, bre, bim) \
{\
pre = (MUL16(are, bre) - MUL16(aim, bim)) >> 15;\
pim = (MUL16(are, bim) + MUL16(bre, aim)) >> 15;\
#define CMUL(pre, pim, are, aim, bre, bim) \
{ \
pre = (MUL16(are, bre) - MUL16(aim, bim)) >> 15; \
pim = (MUL16(are, bim) + MUL16(bre, aim)) >> 15; \
}
/* do a 2^n point complex fft on 2^ln points. */
static void fft(IComplex *z, int ln)
{
int j, l, np, np2;
int nblocks, nloops;
int j, l, np, np2;
int nblocks, nloops;
register IComplex *p,*q;
int tmp_re, tmp_im;
np = 1 << ln;
/* reverse */
for(j=0;j<np;j++) {
for (j = 0; j < np; j++) {
int k = av_reverse[j] >> (8 - ln);
if (k < j)
FFSWAP(IComplex, z[k], z[j]);
@ -163,44 +161,42 @@ static void fft(IComplex *z, int ln)
/* pass 0 */
p=&z[0];
j=(np >> 1);
p = &z[0];
j = np >> 1;
do {
BF(p[0].re, p[0].im, p[1].re, p[1].im,
p[0].re, p[0].im, p[1].re, p[1].im);
p+=2;
} while (--j != 0);
p += 2;
} while (--j);
/* pass 1 */
p=&z[0];
j=np >> 2;
p = &z[0];
j = np >> 2;
do {
BF(p[0].re, p[0].im, p[2].re, p[2].im,
p[0].re, p[0].im, p[2].re, p[2].im);
BF(p[1].re, p[1].im, p[3].re, p[3].im,
BF(p[0].re, p[0].im, p[2].re, p[2].im,
p[0].re, p[0].im, p[2].re, p[2].im);
BF(p[1].re, p[1].im, p[3].re, p[3].im,
p[1].re, p[1].im, p[3].im, -p[3].re);
p+=4;
} while (--j != 0);
} while (--j);
/* pass 2 .. ln-1 */
nblocks = np >> 3;
nloops = 1 << 2;
np2 = np >> 1;
nloops = 1 << 2;
np2 = np >> 1;
do {
p = z;
q = z + nloops;
for (j = 0; j < nblocks; ++j) {
for (j = 0; j < nblocks; j++) {
BF(p->re, p->im, q->re, q->im,
p->re, p->im, q->re, q->im);
p++;
q++;
for(l = nblocks; l < np2; l += nblocks) {
CMUL(tmp_re, tmp_im, costab[l], -sintab[l], q->re, q->im);
BF(p->re, p->im, q->re, q->im,
BF(p->re, p->im, q->re, q->im,
p->re, p->im, tmp_re, tmp_im);
p++;
q++;
@ -209,11 +205,10 @@ static void fft(IComplex *z, int ln)
q += nloops;
}
nblocks = nblocks >> 1;
nloops = nloops << 1;
} while (nblocks != 0);
nloops = nloops << 1;
} while (nblocks);
}
/* do a 512 point mdct */
static void mdct512(int32_t *out, int16_t *in)
{
int i, re, im, re1, im1;
@ -221,14 +216,14 @@ static void mdct512(int32_t *out, int16_t *in)
IComplex x[MDCT_SAMPLES/4];
/* shift to simplify computations */
for(i=0;i<MDCT_SAMPLES/4;i++)
for (i = 0; i < MDCT_SAMPLES/4; i++)
rot[i] = -in[i + 3*MDCT_SAMPLES/4];
for(i=MDCT_SAMPLES/4;i<MDCT_SAMPLES;i++)
rot[i] = in[i - MDCT_SAMPLES/4];
for (;i < MDCT_SAMPLES; i++)
rot[i] = in[i - MDCT_SAMPLES/4];
/* pre rotation */
for(i=0;i<MDCT_SAMPLES/4;i++) {
re = ((int)rot[2*i] - (int)rot[MDCT_SAMPLES-1-2*i]) >> 1;
for (i = 0; i < MDCT_SAMPLES/4; i++) {
re = ((int)rot[ 2*i] - (int)rot[MDCT_SAMPLES -1-2*i]) >> 1;
im = -((int)rot[MDCT_SAMPLES/2+2*i] - (int)rot[MDCT_SAMPLES/2-1-2*i]) >> 1;
CMUL(x[i].re, x[i].im, re, im, -xcos1[i], xsin1[i]);
}
@ -236,26 +231,27 @@ static void mdct512(int32_t *out, int16_t *in)
fft(x, MDCT_NBITS - 2);
/* post rotation */
for(i=0;i<MDCT_SAMPLES/4;i++) {
for (i = 0; i < MDCT_SAMPLES/4; i++) {
re = x[i].re;
im = x[i].im;
CMUL(re1, im1, re, im, xsin1[i], xcos1[i]);
out[2*i] = im1;
out[ 2*i] = im1;
out[MDCT_SAMPLES/2-1-2*i] = re1;
}
}
/* XXX: use another norm ? */
static int calc_exp_diff(uint8_t *exp1, uint8_t *exp2, int n)
{
int sum, i;
sum = 0;
for(i=0;i<n;i++) {
for (i = 0; i < n; i++)
sum += abs(exp1[i] - exp2[i]);
}
return sum;
}
/* new exponents are sent if their Norm 1 exceed this number */
#define EXP_DIFF_THRESHOLD 1000
static void compute_exp_strategy(uint8_t exp_strategy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS],
uint8_t exp[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS],
int ch, int is_lfe)
@ -266,7 +262,7 @@ static void compute_exp_strategy(uint8_t exp_strategy[AC3_MAX_BLOCKS][AC3_MAX_CH
/* estimate if the exponent variation & decide if they should be
reused in the next frame */
exp_strategy[0][ch] = EXP_NEW;
for(i=1;i<AC3_MAX_BLOCKS;i++) {
for (i = 1; i < AC3_MAX_BLOCKS; i++) {
exp_diff = calc_exp_diff(exp[i][ch], exp[i-1][ch], AC3_MAX_COEFS);
if (exp_diff > EXP_DIFF_THRESHOLD)
exp_strategy[i][ch] = EXP_NEW;
@ -283,7 +279,7 @@ static void compute_exp_strategy(uint8_t exp_strategy[AC3_MAX_BLOCKS][AC3_MAX_CH
j = i + 1;
while (j < AC3_MAX_BLOCKS && exp_strategy[j][ch] == EXP_REUSE)
j++;
switch(j - i) {
switch (j - i) {
case 1:
exp_strategy[i][ch] = EXP_D45;
break;
@ -303,8 +299,7 @@ static void compute_exp_strategy(uint8_t exp_strategy[AC3_MAX_BLOCKS][AC3_MAX_CH
static void exponent_min(uint8_t exp[AC3_MAX_COEFS], uint8_t exp1[AC3_MAX_COEFS], int n)
{
int i;
for(i=0;i<n;i++) {
for (i = 0; i < n; i++) {
if (exp1[i] < exp[i])
exp[i] = exp1[i];
}
@ -314,13 +309,12 @@ static void exponent_min(uint8_t exp[AC3_MAX_COEFS], uint8_t exp1[AC3_MAX_COEFS]
decode. Return the number of bits used to code the exponents */
static int encode_exp(uint8_t encoded_exp[AC3_MAX_COEFS],
uint8_t exp[AC3_MAX_COEFS],
int nb_exps,
int exp_strategy)
int nb_exps, int exp_strategy)
{
int group_size, nb_groups, i, j, k, exp_min;
uint8_t exp1[AC3_MAX_COEFS];
switch(exp_strategy) {
switch (exp_strategy) {
case EXP_D15:
group_size = 1;
break;
@ -337,10 +331,10 @@ static int encode_exp(uint8_t encoded_exp[AC3_MAX_COEFS],
/* for each group, compute the minimum exponent */
exp1[0] = exp[0]; /* DC exponent is handled separately */
k = 1;
for(i=1;i<=nb_groups;i++) {
for (i = 1; i <= nb_groups; i++) {
exp_min = exp[k];
assert(exp_min >= 0 && exp_min <= 24);
for(j=1;j<group_size;j++) {
for (j = 1; j < group_size; j++) {
if (exp[k+j] < exp_min)
exp_min = exp[k+j];
}
@ -352,20 +346,19 @@ static int encode_exp(uint8_t encoded_exp[AC3_MAX_COEFS],
if (exp1[0] > 15)
exp1[0] = 15;
/* Decrease the delta between each groups to within 2
* so that they can be differentially encoded */
for (i=1;i<=nb_groups;i++)
/* decrease the delta between each groups to within 2 so that they can be
differentially encoded */
for (i = 1; i <= nb_groups; i++)
exp1[i] = FFMIN(exp1[i], exp1[i-1] + 2);
for (i=nb_groups-1;i>=0;i--)
for (i = nb_groups-1; i >= 0; i--)
exp1[i] = FFMIN(exp1[i], exp1[i+1] + 2);
/* now we have the exponent values the decoder will see */
encoded_exp[0] = exp1[0];
k = 1;
for(i=1;i<=nb_groups;i++) {
for(j=0;j<group_size;j++) {
for (i = 1; i <= nb_groups; i++) {
for (j = 0; j < group_size; j++)
encoded_exp[k+j] = exp1[i];
}
k += group_size;
}
@ -378,9 +371,9 @@ static int compute_mantissa_size(AC3EncodeContext *s, uint8_t *m, int nb_coefs)
int bits, mant, i;
bits = 0;
for(i=0;i<nb_coefs;i++) {
for (i = 0; i < nb_coefs; i++) {
mant = m[i];
switch(mant) {
switch (mant) {
case 0:
/* nothing */
break;
@ -432,8 +425,8 @@ static void bit_alloc_masking(AC3EncodeContext *s,
int blk, ch;
int16_t band_psd[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][50];
for(blk=0; blk<AC3_MAX_BLOCKS; blk++) {
for(ch=0;ch<s->channels;ch++) {
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
for (ch = 0; ch < s->channels; ch++) {
if(exp_strategy[blk][ch] == EXP_REUSE) {
memcpy(psd[blk][ch], psd[blk-1][ch], AC3_MAX_COEFS*sizeof(int16_t));
memcpy(mask[blk][ch], mask[blk-1][ch], 50*sizeof(int16_t));
@ -463,18 +456,16 @@ static int bit_alloc(AC3EncodeContext *s,
snr_offset = (((coarse_snr_offset - 15) << 4) + fine_snr_offset) << 2;
/* compute size */
for(i=0;i<AC3_MAX_BLOCKS;i++) {
for (i = 0; i < AC3_MAX_BLOCKS; i++) {
s->mant1_cnt = 0;
s->mant2_cnt = 0;
s->mant4_cnt = 0;
for(ch=0;ch<s->channels;ch++) {
for (ch = 0; ch < s->channels; ch++) {
ff_ac3_bit_alloc_calc_bap(mask[i][ch], psd[i][ch], 0,
s->nb_coefs[ch], snr_offset,
s->bit_alloc.floor, ff_ac3_bap_tab,
bap[i][ch]);
frame_bits += compute_mantissa_size(s, bap[i][ch],
s->nb_coefs[ch]);
frame_bits += compute_mantissa_size(s, bap[i][ch], s->nb_coefs[ch]);
}
}
return 16 * s->frame_size - frame_bits;
@ -498,18 +489,18 @@ static int compute_bit_allocation(AC3EncodeContext *s,
/* init default parameters */
s->slow_decay_code = 2;
s->fast_decay_code = 1;
s->slow_gain_code = 1;
s->slow_gain_code = 1;
s->db_per_bit_code = 2;
s->floor_code = 4;
for(ch=0;ch<s->channels;ch++)
s->floor_code = 4;
for (ch = 0; ch < s->channels; ch++)
s->fast_gain_code[ch] = 4;
/* compute real values */
s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code] >> s->bit_alloc.sr_shift;
s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code] >> s->bit_alloc.sr_shift;
s->bit_alloc.slow_gain = ff_ac3_slow_gain_tab[s->slow_gain_code];
s->bit_alloc.slow_gain = ff_ac3_slow_gain_tab[s->slow_gain_code];
s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code];
s->bit_alloc.floor = ff_ac3_floor_tab[s->floor_code];
s->bit_alloc.floor = ff_ac3_floor_tab[s->floor_code];
/* header size */
frame_bits += 65;
@ -518,16 +509,17 @@ static int compute_bit_allocation(AC3EncodeContext *s,
frame_bits += frame_bits_inc[s->channel_mode];
/* audio blocks */
for(i=0;i<AC3_MAX_BLOCKS;i++) {
for (i = 0; i < AC3_MAX_BLOCKS; i++) {
frame_bits += s->fbw_channels * 2 + 2; /* blksw * c, dithflag * c, dynrnge, cplstre */
if (s->channel_mode == AC3_CHMODE_STEREO) {
frame_bits++; /* rematstr */
if(i==0) frame_bits += 4;
if (!i)
frame_bits += 4;
}
frame_bits += 2 * s->fbw_channels; /* chexpstr[2] * c */
if (s->lfe_on)
frame_bits++; /* lfeexpstr */
for(ch=0;ch<s->fbw_channels;ch++) {
for (ch = 0; ch < s->fbw_channels; ch++) {
if (exp_strategy[i][ch] != EXP_REUSE)
frame_bits += 6 + 2; /* chbwcod[6], gainrng[2] */
}
@ -562,26 +554,26 @@ static int compute_bit_allocation(AC3EncodeContext *s,
av_log(NULL, AV_LOG_ERROR, "Bit allocation failed. Try increasing the bitrate.\n");
return -1;
}
while ((coarse_snr_offset + SNR_INC1) <= 63 &&
while (coarse_snr_offset + SNR_INC1 <= 63 &&
bit_alloc(s, mask, psd, bap1, frame_bits,
coarse_snr_offset + SNR_INC1, 0) >= 0) {
coarse_snr_offset += SNR_INC1;
memcpy(bap, bap1, sizeof(bap1));
}
while ((coarse_snr_offset + 1) <= 63 &&
while (coarse_snr_offset + 1 <= 63 &&
bit_alloc(s, mask, psd, bap1, frame_bits, coarse_snr_offset + 1, 0) >= 0) {
coarse_snr_offset++;
memcpy(bap, bap1, sizeof(bap1));
}
fine_snr_offset = 0;
while ((fine_snr_offset + SNR_INC1) <= 15 &&
while (fine_snr_offset + SNR_INC1 <= 15 &&
bit_alloc(s, mask, psd, bap1, frame_bits,
coarse_snr_offset, fine_snr_offset + SNR_INC1) >= 0) {
fine_snr_offset += SNR_INC1;
memcpy(bap, bap1, sizeof(bap1));
}
while ((fine_snr_offset + 1) <= 15 &&
while (fine_snr_offset + 1 <= 15 &&
bit_alloc(s, mask, psd, bap1, frame_bits,
coarse_snr_offset, fine_snr_offset + 1) >= 0) {
fine_snr_offset++;
@ -589,7 +581,7 @@ static int compute_bit_allocation(AC3EncodeContext *s,
}
s->coarse_snr_offset = coarse_snr_offset;
for(ch=0;ch<s->channels;ch++)
for (ch = 0; ch < s->channels; ch++)
s->fine_snr_offset[ch] = fine_snr_offset;
return 0;
@ -631,7 +623,7 @@ static av_cold int set_channel_info(AC3EncodeContext *s, int channels,
return -1;
}
s->channel_map = ff_ac3_enc_channel_map[s->channel_mode][s->lfe_on];
s->channel_map = ff_ac3_enc_channel_map[s->channel_mode][s->lfe_on];
*channel_layout = ch_layout;
if (s->lfe_on)
*channel_layout |= AV_CH_LOW_FREQUENCY;
@ -662,39 +654,39 @@ static av_cold int AC3_encode_init(AVCodecContext *avctx)
}
/* frequency */
for(i=0;i<3;i++) {
for(j=0;j<3;j++)
for (i = 0; i < 3; i++) {
for (j = 0; j < 3; j++)
if ((ff_ac3_sample_rate_tab[j] >> i) == freq)
goto found;
}
return -1;
found:
s->sample_rate = freq;
s->sample_rate = freq;
s->bit_alloc.sr_shift = i;
s->bit_alloc.sr_code = j;
s->bitstream_id = 8 + s->bit_alloc.sr_shift;
s->bitstream_mode = 0; /* complete main audio service */
s->bit_alloc.sr_code = j;
s->bitstream_id = 8 + s->bit_alloc.sr_shift;
s->bitstream_mode = 0; /* complete main audio service */
/* bitrate & frame size */
for(i=0;i<19;i++) {
for (i = 0; i < 19; i++) {
if ((ff_ac3_bitrate_tab[i] >> s->bit_alloc.sr_shift)*1000 == bitrate)
break;
}
if (i == 19)
return -1;
s->bit_rate = bitrate;
s->bit_rate = bitrate;
s->frame_size_code = i << 1;
s->frame_size_min = ff_ac3_frame_size_tab[s->frame_size_code][s->bit_alloc.sr_code];
s->bits_written = 0;
s->frame_size_min = ff_ac3_frame_size_tab[s->frame_size_code][s->bit_alloc.sr_code];
s->bits_written = 0;
s->samples_written = 0;
s->frame_size = s->frame_size_min;
s->frame_size = s->frame_size_min;
/* bit allocation init */
/* set bandwidth */
if(avctx->cutoff) {
/* calculate bandwidth based on user-specified cutoff frequency */
int cutoff = av_clip(avctx->cutoff, 1, s->sample_rate >> 1);
int cutoff = av_clip(avctx->cutoff, 1, s->sample_rate >> 1);
int fbw_coeffs = cutoff * 2 * AC3_MAX_COEFS / s->sample_rate;
bw_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
bw_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
} else {
/* use default bandwidth setting */
/* XXX: should compute the bandwidth according to the frame
@ -704,11 +696,11 @@ static av_cold int AC3_encode_init(AVCodecContext *avctx)
for(ch=0;ch<s->fbw_channels;ch++) {
/* bandwidth for each channel */
s->bandwidth_code[ch] = bw_code;
s->nb_coefs[ch] = bw_code * 3 + 73;
}
if (s->lfe_on) {
s->nb_coefs[s->lfe_channel] = 7; /* fixed */
s->nb_coefs[ch] = bw_code * 3 + 73;
}
if (s->lfe_on)
s->nb_coefs[s->lfe_channel] = 7; /* LFE channel always has 7 coefs */
/* initial snr offset */
s->coarse_snr_offset = 40;
@ -725,29 +717,29 @@ static void output_frame_header(AC3EncodeContext *s, unsigned char *frame)
{
init_put_bits(&s->pb, frame, AC3_MAX_CODED_FRAME_SIZE);
put_bits(&s->pb, 16, 0x0b77); /* frame header */
put_bits(&s->pb, 16, 0); /* crc1: will be filled later */
put_bits(&s->pb, 2, s->bit_alloc.sr_code);
put_bits(&s->pb, 6, s->frame_size_code + (s->frame_size - s->frame_size_min));
put_bits(&s->pb, 5, s->bitstream_id);
put_bits(&s->pb, 3, s->bitstream_mode);
put_bits(&s->pb, 3, s->channel_mode);
put_bits(&s->pb, 16, 0x0b77); /* frame header */
put_bits(&s->pb, 16, 0); /* crc1: will be filled later */
put_bits(&s->pb, 2, s->bit_alloc.sr_code);
put_bits(&s->pb, 6, s->frame_size_code + (s->frame_size - s->frame_size_min));
put_bits(&s->pb, 5, s->bitstream_id);
put_bits(&s->pb, 3, s->bitstream_mode);
put_bits(&s->pb, 3, s->channel_mode);
if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)
put_bits(&s->pb, 2, 1); /* XXX -4.5 dB */
put_bits(&s->pb, 2, 1); /* XXX -4.5 dB */
if (s->channel_mode & 0x04)
put_bits(&s->pb, 2, 1); /* XXX -6 dB */
put_bits(&s->pb, 2, 1); /* XXX -6 dB */
if (s->channel_mode == AC3_CHMODE_STEREO)
put_bits(&s->pb, 2, 0); /* surround not indicated */
put_bits(&s->pb, 2, 0); /* surround not indicated */
put_bits(&s->pb, 1, s->lfe_on); /* LFE */
put_bits(&s->pb, 5, 31); /* dialog norm: -31 db */
put_bits(&s->pb, 1, 0); /* no compression control word */
put_bits(&s->pb, 1, 0); /* no lang code */
put_bits(&s->pb, 1, 0); /* no audio production info */
put_bits(&s->pb, 1, 0); /* no copyright */
put_bits(&s->pb, 1, 1); /* original bitstream */
put_bits(&s->pb, 1, 0); /* no time code 1 */
put_bits(&s->pb, 1, 0); /* no time code 2 */
put_bits(&s->pb, 1, 0); /* no additional bit stream info */
put_bits(&s->pb, 5, 31); /* dialog norm: -31 db */
put_bits(&s->pb, 1, 0); /* no compression control word */
put_bits(&s->pb, 1, 0); /* no lang code */
put_bits(&s->pb, 1, 0); /* no audio production info */
put_bits(&s->pb, 1, 0); /* no copyright */
put_bits(&s->pb, 1, 1); /* original bitstream */
put_bits(&s->pb, 1, 0); /* no time code 1 */
put_bits(&s->pb, 1, 0); /* no time code 2 */
put_bits(&s->pb, 1, 0); /* no additional bit stream info */
}
/* symetric quantization on 'levels' levels */
@ -805,55 +797,48 @@ static void output_audio_block(AC3EncodeContext *s,
uint16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr;
int delta0, delta1, delta2;
for(ch=0;ch<s->fbw_channels;ch++)
put_bits(&s->pb, 1, 0); /* 512 point MDCT */
for(ch=0;ch<s->fbw_channels;ch++)
for (ch = 0; ch < s->fbw_channels; ch++)
put_bits(&s->pb, 1, 0); /* no block switching */
for (ch = 0; ch < s->fbw_channels; ch++)
put_bits(&s->pb, 1, 1); /* no dither */
put_bits(&s->pb, 1, 0); /* no dynamic range */
if (block_num == 0) {
/* for block 0, even if no coupling, we must say it. This is a
waste of bit :-) */
put_bits(&s->pb, 1, 0); /* no dynamic range */
if (!block_num) {
put_bits(&s->pb, 1, 1); /* coupling strategy present */
put_bits(&s->pb, 1, 0); /* no coupling strategy */
} else {
put_bits(&s->pb, 1, 0); /* no new coupling strategy */
}
if (s->channel_mode == AC3_CHMODE_STEREO)
{
if(block_num==0)
{
/* first block must define rematrixing (rematstr) */
if (s->channel_mode == AC3_CHMODE_STEREO) {
if (!block_num) {
/* first block must define rematrixing (rematstr) */
put_bits(&s->pb, 1, 1);
/* dummy rematrixing rematflg(1:4)=0 */
for (rbnd=0;rbnd<4;rbnd++)
put_bits(&s->pb, 1, 0);
}
else
{
for (rbnd = 0; rbnd < 4; rbnd++)
put_bits(&s->pb, 1, 0);
} else {
/* no matrixing (but should be used in the future) */
put_bits(&s->pb, 1, 0);
}
}
}
}
/* exponent strategy */
for(ch=0;ch<s->fbw_channels;ch++) {
for (ch = 0; ch < s->fbw_channels; ch++)
put_bits(&s->pb, 2, exp_strategy[ch]);
}
if (s->lfe_on) {
if (s->lfe_on)
put_bits(&s->pb, 1, exp_strategy[s->lfe_channel]);
}
for(ch=0;ch<s->fbw_channels;ch++) {
/* bandwidth */
for (ch = 0; ch < s->fbw_channels; ch++) {
if (exp_strategy[ch] != EXP_REUSE)
put_bits(&s->pb, 6, s->bandwidth_code[ch]);
}
/* exponents */
for (ch = 0; ch < s->channels; ch++) {
switch(exp_strategy[ch]) {
switch (exp_strategy[ch]) {
case EXP_REUSE:
continue;
case EXP_D15:
@ -875,21 +860,21 @@ static void output_audio_block(AC3EncodeContext *s,
put_bits(&s->pb, 4, exp1);
/* next ones are delta encoded */
for(i=0;i<nb_groups;i++) {
for (i = 0; i < nb_groups; i++) {
/* merge three delta in one code */
exp0 = exp1;
exp1 = p[0];
p += group_size;
exp0 = exp1;
exp1 = p[0];
p += group_size;
delta0 = exp1 - exp0 + 2;
exp0 = exp1;
exp1 = p[0];
p += group_size;
exp0 = exp1;
exp1 = p[0];
p += group_size;
delta1 = exp1 - exp0 + 2;
exp0 = exp1;
exp1 = p[0];
p += group_size;
exp0 = exp1;
exp1 = p[0];
p += group_size;
delta2 = exp1 - exp0 + 2;
put_bits(&s->pb, 7, ((delta0 * 5 + delta1) * 5) + delta2);
@ -911,10 +896,10 @@ static void output_audio_block(AC3EncodeContext *s,
}
/* snr offset */
put_bits(&s->pb, 1, baie); /* always present with bai */
put_bits(&s->pb, 1, baie);
if (baie) {
put_bits(&s->pb, 6, s->coarse_snr_offset);
for(ch=0;ch<s->channels;ch++) {
for (ch = 0; ch < s->channels; ch++) {
put_bits(&s->pb, 4, s->fine_snr_offset[ch]);
put_bits(&s->pb, 3, s->fast_gain_code[ch]);
}
@ -934,17 +919,17 @@ static void output_audio_block(AC3EncodeContext *s,
for (ch = 0; ch < s->channels; ch++) {
int b, c, e, v;
for(i=0;i<s->nb_coefs[ch];i++) {
for (i = 0; i < s->nb_coefs[ch]; i++) {
c = mdct_coefs[ch][i];
e = encoded_exp[ch][i] - global_exp[ch];
b = bap[ch][i];
switch(b) {
switch (b) {
case 0:
v = 0;
break;
case 1:
v = sym_quant(c, e, 3);
switch(mant1_cnt) {
switch (mant1_cnt) {
case 0:
qmant1_ptr = &qmant[ch][i];
v = 9 * v;
@ -964,7 +949,7 @@ static void output_audio_block(AC3EncodeContext *s,
break;
case 2:
v = sym_quant(c, e, 5);
switch(mant2_cnt) {
switch (mant2_cnt) {
case 0:
qmant2_ptr = &qmant[ch][i];
v = 25 * v;
@ -987,7 +972,7 @@ static void output_audio_block(AC3EncodeContext *s,
break;
case 4:
v = sym_quant(c, e, 11);
switch(mant4_cnt) {
switch (mant4_cnt) {
case 0:
qmant4_ptr = &qmant[ch][i];
v = 11 * v;
@ -1021,36 +1006,18 @@ static void output_audio_block(AC3EncodeContext *s,
for (ch = 0; ch < s->channels; ch++) {
int b, q;
for(i=0;i<s->nb_coefs[ch];i++) {
for (i = 0; i < s->nb_coefs[ch]; i++) {
q = qmant[ch][i];
b = bap[ch][i];
switch(b) {
case 0:
break;
case 1:
if (q != 128)
put_bits(&s->pb, 5, q);
break;
case 2:
if (q != 128)
put_bits(&s->pb, 7, q);
break;
case 3:
put_bits(&s->pb, 3, q);
break;
case 4:
if (q != 128)
put_bits(&s->pb, 7, q);
break;
case 14:
put_bits(&s->pb, 14, q);
break;
case 15:
put_bits(&s->pb, 16, q);
break;
default:
put_bits(&s->pb, b - 1, q);
break;
switch (b) {
case 0: break;
case 1: if (q != 128) put_bits(&s->pb, 5, q); break;
case 2: if (q != 128) put_bits(&s->pb, 7, q); break;
case 3: put_bits(&s->pb, 3, q); break;
case 4: if (q != 128) put_bits(&s->pb, 7, q); break;
case 14: put_bits(&s->pb, 14, q); break;
case 15: put_bits(&s->pb, 16, q); break;
default: put_bits(&s->pb, b-1, q); break;
}
}
}
@ -1094,9 +1061,9 @@ static int log2_tab(int16_t *tab, int n)
int i, v;
v = 0;
for(i=0;i<n;i++) {
for (i = 0; i < n; i++)
v |= abs(tab[i]);
}
return av_log2(v);
}
@ -1105,14 +1072,12 @@ static void lshift_tab(int16_t *tab, int n, int lshift)
int i;
if (lshift > 0) {
for(i=0;i<n;i++) {
for(i = 0; i < n; i++)
tab[i] <<= lshift;
}
} else if (lshift < 0) {
lshift = -lshift;
for(i=0;i<n;i++) {
for (i = 0; i < n; i++)
tab[i] >>= lshift;
}
}
}
@ -1129,25 +1094,26 @@ static int output_frame_end(AC3EncodeContext *s)
frame = s->pb.buf;
n = 2 * s->frame_size - (put_bits_ptr(&s->pb) - frame) - 2;
assert(n >= 0);
if(n>0)
memset(put_bits_ptr(&s->pb), 0, n);
if (n > 0)
memset(put_bits_ptr(&s->pb), 0, n);
/* Now we must compute both crcs : this is not so easy for crc1
because it is at the beginning of the data... */
frame_size_58 = (frame_size >> 1) + (frame_size >> 3);
crc1 = av_bswap16(av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0,
frame + 4, 2 * frame_size_58 - 4));
frame + 4, 2 * frame_size_58 - 4));
/* 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);
AV_WB16(frame+2,crc1);
crc1 = mul_poly(crc_inv, crc1, CRC16_POLY);
AV_WB16(frame + 2, crc1);
crc2 = av_bswap16(av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0,
frame + 2 * frame_size_58,
(frame_size - frame_size_58) * 2 - 2));
AV_WB16(frame+2*frame_size-2,crc2);
frame + 2 * frame_size_58,
(frame_size - frame_size_58) * 2 - 2));
AV_WB16(frame + 2*frame_size - 2, crc2);
// printf("n=%d frame_size=%d\n", n, frame_size);
return frame_size * 2;
}
@ -1167,10 +1133,10 @@ static int AC3_encode_frame(AVCodecContext *avctx,
int frame_bits;
frame_bits = 0;
for(ch=0;ch<s->channels;ch++) {
for (ch = 0; ch < s->channels; ch++) {
int ich = s->channel_map[ch];
/* fixed mdct to the six sub blocks & exponent computation */
for(i=0;i<AC3_MAX_BLOCKS;i++) {
for (i = 0; i < AC3_MAX_BLOCKS; i++) {
const int16_t *sptr;
int sinc;
@ -1178,7 +1144,7 @@ static int AC3_encode_frame(AVCodecContext *avctx,
memcpy(input_samples, s->last_samples[ich], AC3_BLOCK_SIZE * sizeof(int16_t));
sinc = s->channels;
sptr = samples + (sinc * AC3_BLOCK_SIZE * i) + ich;
for(j=0;j<AC3_BLOCK_SIZE;j++) {
for (j = 0; j < AC3_BLOCK_SIZE; j++) {
v = *sptr;
input_samples[j + AC3_BLOCK_SIZE] = v;
s->last_samples[ich][j] = v;
@ -1186,15 +1152,14 @@ static int AC3_encode_frame(AVCodecContext *avctx,
}
/* apply the MDCT window */
for(j=0;j<AC3_BLOCK_SIZE;j++) {
input_samples[j] = MUL16(input_samples[j],
ff_ac3_window[j]) >> 15;
for (j = 0; j < AC3_BLOCK_SIZE; j++) {
input_samples[j] = MUL16(input_samples[j],
ff_ac3_window[j]) >> 15;
input_samples[AC3_WINDOW_SIZE-j-1] = MUL16(input_samples[AC3_WINDOW_SIZE-j-1],
ff_ac3_window[j]) >> 15;
ff_ac3_window[j]) >> 15;
}
/* Normalize the samples to use the maximum available
precision */
/* Normalize the samples to use the maximum available precision */
v = 14 - log2_tab(input_samples, AC3_WINDOW_SIZE);
if (v < 0)
v = 0;
@ -1204,9 +1169,8 @@ static int AC3_encode_frame(AVCodecContext *avctx,
/* do the MDCT */
mdct512(mdct_coef[i][ch], input_samples);
/* compute "exponents". We take into account the
normalization there */
for(j=0;j<AC3_MAX_COEFS;j++) {
/* compute "exponents". We take into account the normalization there */
for (j = 0; j < AC3_MAX_COEFS; j++) {
int e;
v = abs(mdct_coef[i][ch][j]);
if (v == 0)
@ -1238,7 +1202,7 @@ static int AC3_encode_frame(AVCodecContext *avctx,
exp[i][ch], s->nb_coefs[ch],
exp_strategy[i][ch]);
/* copy encoded exponents for reuse case */
for(k=i+1;k<j;k++) {
for (k = i+1; k < j; k++) {
memcpy(encoded_exp[k][ch], encoded_exp[i][ch],
s->nb_coefs[ch] * sizeof(uint8_t));
}
@ -1247,19 +1211,19 @@ static int AC3_encode_frame(AVCodecContext *avctx,
}
/* adjust for fractional frame sizes */
while(s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
s->bits_written -= s->bit_rate;
while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
s->bits_written -= s->bit_rate;
s->samples_written -= s->sample_rate;
}
s->frame_size = s->frame_size_min + (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);
s->bits_written += s->frame_size * 16;
s->bits_written += s->frame_size * 16;
s->samples_written += AC3_FRAME_SIZE;
compute_bit_allocation(s, bap, encoded_exp, exp_strategy, frame_bits);
/* everything is known... let's output the frame */
output_frame_header(s, frame);
for(i=0;i<AC3_MAX_BLOCKS;i++) {
for (i = 0; i < AC3_MAX_BLOCKS; i++) {
output_audio_block(s, exp_strategy[i], encoded_exp[i],
bap[i], mdct_coef[i], exp_samples[i], i);
}
@ -1286,20 +1250,18 @@ static void fft_test(AVLFG *lfg)
int k, n, i;
float sum_re, sum_im, a;
/* FFT test */
for(i=0;i<FN;i++) {
for (i = 0; i < FN; i++) {
in[i].re = av_lfg_get(lfg) % 65535 - 32767;
in[i].im = av_lfg_get(lfg) % 65535 - 32767;
in1[i] = in[i];
in1[i] = in[i];
}
fft(in, 7);
/* do it by hand */
for(k=0;k<FN;k++) {
for (k = 0; k < FN; k++) {
sum_re = 0;
sum_im = 0;
for(n=0;n<FN;n++) {
for (n = 0; n < FN; n++) {
a = -2 * M_PI * (n * k) / FN;
sum_re += in1[n].re * cos(a) - in1[n].im * sin(a);
sum_im += in1[n].re * sin(a) + in1[n].im * cos(a);
@ -1318,26 +1280,26 @@ static void mdct_test(AVLFG *lfg)
float s, a, err, e, emax;
int i, k, n;
for(i=0;i<MDCT_SAMPLES;i++) {
input[i] = (av_lfg_get(lfg) % 65535 - 32767) * 9 / 10;
for (i = 0; i < MDCT_SAMPLES; i++) {
input[i] = (av_lfg_get(lfg) % 65535 - 32767) * 9 / 10;
input1[i] = input[i];
}
mdct512(output, input);
/* do it by hand */
for(k=0;k<AC3_MAX_COEFS;k++) {
for (k = 0; k < AC3_MAX_COEFS; k++) {
s = 0;
for(n=0;n<MDCT_SAMPLES;n++) {
for (n = 0; n < MDCT_SAMPLES; n++) {
a = (2*M_PI*(2*n+1+MDCT_SAMPLES/2)*(2*k+1) / (4 * MDCT_SAMPLES));
s += input1[n] * cos(a);
}
output1[k] = -2 * s / MDCT_SAMPLES;
}
err = 0;
err = 0;
emax = 0;
for(i=0;i<AC3_MAX_COEFS;i++) {
for (i = 0; i < AC3_MAX_COEFS; i++) {
av_log(NULL, AV_LOG_DEBUG, "%3d: %7d %7.0f\n", i, output[i], output1[i]);
e = output[i] - output1[i];
if (e > emax)

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