ffmpeg / libavcodec / mpegaudiodec.c @ 6122b733
History  View  Annotate  Download (79.9 KB)
1 
/*


2 
* MPEG Audio decoder

3 
* Copyright (c) 2001, 2002 Fabrice Bellard.

4 
*

5 
* This file is part of FFmpeg.

6 
*

7 
* FFmpeg is free software; you can redistribute it and/or

8 
* modify it under the terms of the GNU Lesser General Public

9 
* License as published by the Free Software Foundation; either

10 
* version 2.1 of the License, or (at your option) any later version.

11 
*

12 
* FFmpeg is distributed in the hope that it will be useful,

13 
* but WITHOUT ANY WARRANTY; without even the implied warranty of

14 
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

15 
* Lesser General Public License for more details.

16 
*

17 
* You should have received a copy of the GNU Lesser General Public

18 
* License along with FFmpeg; if not, write to the Free Software

19 
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 021101301 USA

20 
*/

21  
22 
/**

23 
* @file mpegaudiodec.c

24 
* MPEG Audio decoder.

25 
*/

26  
27 
//#define DEBUG

28 
#include "avcodec.h" 
29 
#include "bitstream.h" 
30 
#include "dsputil.h" 
31  
32 
/*

33 
* TODO:

34 
*  in low precision mode, use more 16 bit multiplies in synth filter

35 
*  test lsf / mpeg25 extensively.

36 
*/

37  
38 
/* define USE_HIGHPRECISION to have a bit exact (but slower) mpeg

39 
audio decoder */

40 
#ifdef CONFIG_MPEGAUDIO_HP

41 
# define USE_HIGHPRECISION

42 
#endif

43  
44 
#include "mpegaudio.h" 
45 
#include "mpegaudiodecheader.h" 
46  
47 
#include "mathops.h" 
48  
49 
/* WARNING: only correct for posititive numbers */

50 
#define FIXR(a) ((int)((a) * FRAC_ONE + 0.5)) 
51 
#define FRAC_RND(a) (((a) + (FRAC_ONE/2)) >> FRAC_BITS) 
52  
53 
#define FIXHR(a) ((int)((a) * (1LL<<32) + 0.5)) 
54  
55 
/****************/

56  
57 
#define HEADER_SIZE 4 
58  
59 
/**

60 
* Context for MP3On4 decoder

61 
*/

62 
typedef struct MP3On4DecodeContext { 
63 
int frames; ///< number of mp3 frames per block (number of mp3 decoder instances) 
64 
int chan_cfg; ///< channel config number 
65 
MPADecodeContext *mp3decctx[5]; ///< MPADecodeContext for every decoder instance 
66 
} MP3On4DecodeContext; 
67  
68 
/* layer 3 "granule" */

69 
typedef struct GranuleDef { 
70 
uint8_t scfsi; 
71 
int part2_3_length;

72 
int big_values;

73 
int global_gain;

74 
int scalefac_compress;

75 
uint8_t block_type; 
76 
uint8_t switch_point; 
77 
int table_select[3]; 
78 
int subblock_gain[3]; 
79 
uint8_t scalefac_scale; 
80 
uint8_t count1table_select; 
81 
int region_size[3]; /* number of huffman codes in each region */ 
82 
int preflag;

83 
int short_start, long_end; /* long/short band indexes */ 
84 
uint8_t scale_factors[40];

85 
int32_t sb_hybrid[SBLIMIT * 18]; /* 576 samples */ 
86 
} GranuleDef; 
87  
88 
#include "mpegaudiodata.h" 
89 
#include "mpegaudiodectab.h" 
90  
91 
static void compute_antialias_integer(MPADecodeContext *s, GranuleDef *g); 
92 
static void compute_antialias_float(MPADecodeContext *s, GranuleDef *g); 
93  
94 
/* vlc structure for decoding layer 3 huffman tables */

95 
static VLC huff_vlc[16]; 
96 
static VLC huff_quad_vlc[2]; 
97 
/* computed from band_size_long */

98 
static uint16_t band_index_long[9][23]; 
99 
/* XXX: free when all decoders are closed */

100 
#define TABLE_4_3_SIZE (8191 + 16)*4 
101 
static int8_t table_4_3_exp[TABLE_4_3_SIZE];

102 
static uint32_t table_4_3_value[TABLE_4_3_SIZE];

103 
static uint32_t exp_table[512]; 
104 
static uint32_t expval_table[512][16]; 
105 
/* intensity stereo coef table */

106 
static int32_t is_table[2][16]; 
107 
static int32_t is_table_lsf[2][2][16]; 
108 
static int32_t csa_table[8][4]; 
109 
static float csa_table_float[8][4]; 
110 
static int32_t mdct_win[8][36]; 
111  
112 
/* lower 2 bits: modulo 3, higher bits: shift */

113 
static uint16_t scale_factor_modshift[64]; 
114 
/* [i][j]: 2^(j/3) * FRAC_ONE * 2^(i+2) / (2^(i+2)  1) */

115 
static int32_t scale_factor_mult[15][3]; 
116 
/* mult table for layer 2 group quantization */

117  
118 
#define SCALE_GEN(v) \

119 
{ FIXR(1.0 * (v)), FIXR(0.7937005259 * (v)), FIXR(0.6299605249 * (v)) } 
120  
121 
static const int32_t scale_factor_mult2[3][3] = { 
122 
SCALE_GEN(4.0 / 3.0), /* 3 steps */ 
123 
SCALE_GEN(4.0 / 5.0), /* 5 steps */ 
124 
SCALE_GEN(4.0 / 9.0), /* 9 steps */ 
125 
}; 
126  
127 
static DECLARE_ALIGNED_16(MPA_INT, window[512]); 
128  
129 
/**

130 
* Convert region offsets to region sizes and truncate

131 
* size to big_values.

132 
*/

133 
void ff_region_offset2size(GranuleDef *g){

134 
int i, k, j=0; 
135 
g>region_size[2] = (576 / 2); 
136 
for(i=0;i<3;i++) { 
137 
k = FFMIN(g>region_size[i], g>big_values); 
138 
g>region_size[i] = k  j; 
139 
j = k; 
140 
} 
141 
} 
142  
143 
void ff_init_short_region(MPADecodeContext *s, GranuleDef *g){

144 
if (g>block_type == 2) 
145 
g>region_size[0] = (36 / 2); 
146 
else {

147 
if (s>sample_rate_index <= 2) 
148 
g>region_size[0] = (36 / 2); 
149 
else if (s>sample_rate_index != 8) 
150 
g>region_size[0] = (54 / 2); 
151 
else

152 
g>region_size[0] = (108 / 2); 
153 
} 
154 
g>region_size[1] = (576 / 2); 
155 
} 
156  
157 
void ff_init_long_region(MPADecodeContext *s, GranuleDef *g, int ra1, int ra2){ 
158 
int l;

159 
g>region_size[0] =

160 
band_index_long[s>sample_rate_index][ra1 + 1] >> 1; 
161 
/* should not overflow */

162 
l = FFMIN(ra1 + ra2 + 2, 22); 
163 
g>region_size[1] =

164 
band_index_long[s>sample_rate_index][l] >> 1;

165 
} 
166  
167 
void ff_compute_band_indexes(MPADecodeContext *s, GranuleDef *g){

168 
if (g>block_type == 2) { 
169 
if (g>switch_point) {

170 
/* if switched mode, we handle the 36 first samples as

171 
long blocks. For 8000Hz, we handle the 48 first

172 
exponents as long blocks (XXX: check this!) */

173 
if (s>sample_rate_index <= 2) 
174 
g>long_end = 8;

175 
else if (s>sample_rate_index != 8) 
176 
g>long_end = 6;

177 
else

178 
g>long_end = 4; /* 8000 Hz */ 
179  
180 
g>short_start = 2 + (s>sample_rate_index != 8); 
181 
} else {

182 
g>long_end = 0;

183 
g>short_start = 0;

184 
} 
185 
} else {

186 
g>short_start = 13;

187 
g>long_end = 22;

188 
} 
189 
} 
190  
191 
/* layer 1 unscaling */

192 
/* n = number of bits of the mantissa minus 1 */

193 
static inline int l1_unscale(int n, int mant, int scale_factor) 
194 
{ 
195 
int shift, mod;

196 
int64_t val; 
197  
198 
shift = scale_factor_modshift[scale_factor]; 
199 
mod = shift & 3;

200 
shift >>= 2;

201 
val = MUL64(mant + (1 << n) + 1, scale_factor_mult[n1][mod]); 
202 
shift += n; 
203 
/* NOTE: at this point, 1 <= shift >= 21 + 15 */

204 
return (int)((val + (1LL << (shift  1))) >> shift); 
205 
} 
206  
207 
static inline int l2_unscale_group(int steps, int mant, int scale_factor) 
208 
{ 
209 
int shift, mod, val;

210  
211 
shift = scale_factor_modshift[scale_factor]; 
212 
mod = shift & 3;

213 
shift >>= 2;

214  
215 
val = (mant  (steps >> 1)) * scale_factor_mult2[steps >> 2][mod]; 
216 
/* NOTE: at this point, 0 <= shift <= 21 */

217 
if (shift > 0) 
218 
val = (val + (1 << (shift  1))) >> shift; 
219 
return val;

220 
} 
221  
222 
/* compute value^(4/3) * 2^(exponent/4). It normalized to FRAC_BITS */

223 
static inline int l3_unscale(int value, int exponent) 
224 
{ 
225 
unsigned int m; 
226 
int e;

227  
228 
e = table_4_3_exp [4*value + (exponent&3)]; 
229 
m = table_4_3_value[4*value + (exponent&3)]; 
230 
e = (exponent >> 2);

231 
assert(e>=1);

232 
if (e > 31) 
233 
return 0; 
234 
m = (m + (1 << (e1))) >> e; 
235  
236 
return m;

237 
} 
238  
239 
/* all integer n^(4/3) computation code */

240 
#define DEV_ORDER 13 
241  
242 
#define POW_FRAC_BITS 24 
243 
#define POW_FRAC_ONE (1 << POW_FRAC_BITS) 
244 
#define POW_FIX(a) ((int)((a) * POW_FRAC_ONE)) 
245 
#define POW_MULL(a,b) (((int64_t)(a) * (int64_t)(b)) >> POW_FRAC_BITS)

246  
247 
static int dev_4_3_coefs[DEV_ORDER]; 
248  
249 
#if 0 /* unused */

250 
static int pow_mult3[3] = {

251 
POW_FIX(1.0),

252 
POW_FIX(1.25992104989487316476),

253 
POW_FIX(1.58740105196819947474),

254 
};

255 
#endif

256  
257 
static void int_pow_init(void) 
258 
{ 
259 
int i, a;

260  
261 
a = POW_FIX(1.0); 
262 
for(i=0;i<DEV_ORDER;i++) { 
263 
a = POW_MULL(a, POW_FIX(4.0 / 3.0)  i * POW_FIX(1.0)) / (i + 1); 
264 
dev_4_3_coefs[i] = a; 
265 
} 
266 
} 
267  
268 
#if 0 /* unused, remove? */

269 
/* return the mantissa and the binary exponent */

270 
static int int_pow(int i, int *exp_ptr)

271 
{

272 
int e, er, eq, j;

273 
int a, a1;

274 

275 
/* renormalize */

276 
a = i;

277 
e = POW_FRAC_BITS;

278 
while (a < (1 << (POW_FRAC_BITS  1))) {

279 
a = a << 1;

280 
e;

281 
}

282 
a = (1 << POW_FRAC_BITS);

283 
a1 = 0;

284 
for(j = DEV_ORDER  1; j >= 0; j)

285 
a1 = POW_MULL(a, dev_4_3_coefs[j] + a1);

286 
a = (1 << POW_FRAC_BITS) + a1;

287 
/* exponent compute (exact) */

288 
e = e * 4;

289 
er = e % 3;

290 
eq = e / 3;

291 
a = POW_MULL(a, pow_mult3[er]);

292 
while (a >= 2 * POW_FRAC_ONE) {

293 
a = a >> 1;

294 
eq++;

295 
}

296 
/* convert to float */

297 
while (a < POW_FRAC_ONE) {

298 
a = a << 1;

299 
eq;

300 
}

301 
/* now POW_FRAC_ONE <= a < 2 * POW_FRAC_ONE */

302 
#if POW_FRAC_BITS > FRAC_BITS

303 
a = (a + (1 << (POW_FRAC_BITS  FRAC_BITS  1))) >> (POW_FRAC_BITS  FRAC_BITS);

304 
/* correct overflow */

305 
if (a >= 2 * (1 << FRAC_BITS)) {

306 
a = a >> 1;

307 
eq++;

308 
}

309 
#endif

310 
*exp_ptr = eq; 
311 
return a;

312 
} 
313 
#endif

314  
315 
static int decode_init(AVCodecContext * avctx) 
316 
{ 
317 
MPADecodeContext *s = avctx>priv_data; 
318 
static int init=0; 
319 
int i, j, k;

320  
321 
s>avctx = avctx; 
322  
323 
#if defined(USE_HIGHPRECISION) && defined(CONFIG_AUDIO_NONSHORT)

324 
avctx>sample_fmt= SAMPLE_FMT_S32; 
325 
#else

326 
avctx>sample_fmt= SAMPLE_FMT_S16; 
327 
#endif

328 
s>error_resilience= avctx>error_resilience; 
329  
330 
if(avctx>antialias_algo != FF_AA_FLOAT)

331 
s>compute_antialias= compute_antialias_integer; 
332 
else

333 
s>compute_antialias= compute_antialias_float; 
334  
335 
if (!init && !avctx>parse_only) {

336 
/* scale factors table for layer 1/2 */

337 
for(i=0;i<64;i++) { 
338 
int shift, mod;

339 
/* 1.0 (i = 3) is normalized to 2 ^ FRAC_BITS */

340 
shift = (i / 3);

341 
mod = i % 3;

342 
scale_factor_modshift[i] = mod  (shift << 2);

343 
} 
344  
345 
/* scale factor multiply for layer 1 */

346 
for(i=0;i<15;i++) { 
347 
int n, norm;

348 
n = i + 2;

349 
norm = ((INT64_C(1) << n) * FRAC_ONE) / ((1 << n)  1); 
350 
scale_factor_mult[i][0] = MULL(FIXR(1.0 * 2.0), norm); 
351 
scale_factor_mult[i][1] = MULL(FIXR(0.7937005259 * 2.0), norm); 
352 
scale_factor_mult[i][2] = MULL(FIXR(0.6299605249 * 2.0), norm); 
353 
dprintf(avctx, "%d: norm=%x s=%x %x %x\n",

354 
i, norm, 
355 
scale_factor_mult[i][0],

356 
scale_factor_mult[i][1],

357 
scale_factor_mult[i][2]);

358 
} 
359  
360 
ff_mpa_synth_init(window); 
361  
362 
/* huffman decode tables */

363 
for(i=1;i<16;i++) { 
364 
const HuffTable *h = &mpa_huff_tables[i];

365 
int xsize, x, y;

366 
unsigned int n; 
367 
uint8_t tmp_bits [512];

368 
uint16_t tmp_codes[512];

369  
370 
memset(tmp_bits , 0, sizeof(tmp_bits )); 
371 
memset(tmp_codes, 0, sizeof(tmp_codes)); 
372  
373 
xsize = h>xsize; 
374 
n = xsize * xsize; 
375  
376 
j = 0;

377 
for(x=0;x<xsize;x++) { 
378 
for(y=0;y<xsize;y++){ 
379 
tmp_bits [(x << 5)  y  ((x&&y)<<4)]= h>bits [j ]; 
380 
tmp_codes[(x << 5)  y  ((x&&y)<<4)]= h>codes[j++]; 
381 
} 
382 
} 
383  
384 
/* XXX: fail test */

385 
init_vlc(&huff_vlc[i], 7, 512, 
386 
tmp_bits, 1, 1, tmp_codes, 2, 2, 1); 
387 
} 
388 
for(i=0;i<2;i++) { 
389 
init_vlc(&huff_quad_vlc[i], i == 0 ? 7 : 4, 16, 
390 
mpa_quad_bits[i], 1, 1, mpa_quad_codes[i], 1, 1, 1); 
391 
} 
392  
393 
for(i=0;i<9;i++) { 
394 
k = 0;

395 
for(j=0;j<22;j++) { 
396 
band_index_long[i][j] = k; 
397 
k += band_size_long[i][j]; 
398 
} 
399 
band_index_long[i][22] = k;

400 
} 
401  
402 
/* compute n ^ (4/3) and store it in mantissa/exp format */

403  
404 
int_pow_init(); 
405 
for(i=1;i<TABLE_4_3_SIZE;i++) { 
406 
double f, fm;

407 
int e, m;

408 
f = pow((double)(i/4), 4.0 / 3.0) * pow(2, (i&3)*0.25); 
409 
fm = frexp(f, &e); 
410 
m = (uint32_t)(fm*(1LL<<31) + 0.5); 
411 
e+= FRAC_BITS  31 + 5  100; 
412  
413 
/* normalized to FRAC_BITS */

414 
table_4_3_value[i] = m; 
415 
// av_log(NULL, AV_LOG_DEBUG, "%d %d %f\n", i, m, pow((double)i, 4.0 / 3.0));

416 
table_4_3_exp[i] = e; 
417 
} 
418 
for(i=0; i<512*16; i++){ 
419 
int exponent= (i>>4); 
420 
double f= pow(i&15, 4.0 / 3.0) * pow(2, (exponent400)*0.25 + FRAC_BITS + 5); 
421 
expval_table[exponent][i&15]= llrint(f);

422 
if((i&15)==1) 
423 
exp_table[exponent]= llrint(f); 
424 
} 
425  
426 
for(i=0;i<7;i++) { 
427 
float f;

428 
int v;

429 
if (i != 6) { 
430 
f = tan((double)i * M_PI / 12.0); 
431 
v = FIXR(f / (1.0 + f)); 
432 
} else {

433 
v = FIXR(1.0); 
434 
} 
435 
is_table[0][i] = v;

436 
is_table[1][6  i] = v; 
437 
} 
438 
/* invalid values */

439 
for(i=7;i<16;i++) 
440 
is_table[0][i] = is_table[1][i] = 0.0; 
441  
442 
for(i=0;i<16;i++) { 
443 
double f;

444 
int e, k;

445  
446 
for(j=0;j<2;j++) { 
447 
e = (j + 1) * ((i + 1) >> 1); 
448 
f = pow(2.0, e / 4.0); 
449 
k = i & 1;

450 
is_table_lsf[j][k ^ 1][i] = FIXR(f);

451 
is_table_lsf[j][k][i] = FIXR(1.0); 
452 
dprintf(avctx, "is_table_lsf %d %d: %x %x\n",

453 
i, j, is_table_lsf[j][0][i], is_table_lsf[j][1][i]); 
454 
} 
455 
} 
456  
457 
for(i=0;i<8;i++) { 
458 
float ci, cs, ca;

459 
ci = ci_table[i]; 
460 
cs = 1.0 / sqrt(1.0 + ci * ci); 
461 
ca = cs * ci; 
462 
csa_table[i][0] = FIXHR(cs/4); 
463 
csa_table[i][1] = FIXHR(ca/4); 
464 
csa_table[i][2] = FIXHR(ca/4) + FIXHR(cs/4); 
465 
csa_table[i][3] = FIXHR(ca/4)  FIXHR(cs/4); 
466 
csa_table_float[i][0] = cs;

467 
csa_table_float[i][1] = ca;

468 
csa_table_float[i][2] = ca + cs;

469 
csa_table_float[i][3] = ca  cs;

470 
// printf("%d %d %d %d\n", FIX(cs), FIX(cs1), FIX(ca), FIX(cs)FIX(ca));

471 
// av_log(NULL, AV_LOG_DEBUG,"%f %f %f %f\n", cs, ca, ca+cs, cacs);

472 
} 
473  
474 
/* compute mdct windows */

475 
for(i=0;i<36;i++) { 
476 
for(j=0; j<4; j++){ 
477 
double d;

478  
479 
if(j==2 && i%3 != 1) 
480 
continue;

481  
482 
d= sin(M_PI * (i + 0.5) / 36.0); 
483 
if(j==1){ 
484 
if (i>=30) d= 0; 
485 
else if(i>=24) d= sin(M_PI * (i  18 + 0.5) / 12.0); 
486 
else if(i>=18) d= 1; 
487 
}else if(j==3){ 
488 
if (i< 6) d= 0; 
489 
else if(i< 12) d= sin(M_PI * (i  6 + 0.5) / 12.0); 
490 
else if(i< 18) d= 1; 
491 
} 
492 
//merge last stage of imdct into the window coefficients

493 
d*= 0.5 / cos(M_PI*(2*i + 19)/72); 
494  
495 
if(j==2) 
496 
mdct_win[j][i/3] = FIXHR((d / (1<<5))); 
497 
else

498 
mdct_win[j][i ] = FIXHR((d / (1<<5))); 
499 
// av_log(NULL, AV_LOG_DEBUG, "%2d %d %f\n", i,j,d / (1<<5));

500 
} 
501 
} 
502  
503 
/* NOTE: we do frequency inversion adter the MDCT by changing

504 
the sign of the right window coefs */

505 
for(j=0;j<4;j++) { 
506 
for(i=0;i<36;i+=2) { 
507 
mdct_win[j + 4][i] = mdct_win[j][i];

508 
mdct_win[j + 4][i + 1] = mdct_win[j][i + 1]; 
509 
} 
510 
} 
511  
512 
#if defined(DEBUG)

513 
for(j=0;j<8;j++) { 
514 
av_log(avctx, AV_LOG_DEBUG, "win%d=\n", j);

515 
for(i=0;i<36;i++) 
516 
av_log(avctx, AV_LOG_DEBUG, "%f, ", (double)mdct_win[j][i] / FRAC_ONE); 
517 
av_log(avctx, AV_LOG_DEBUG, "\n");

518 
} 
519 
#endif

520 
init = 1;

521 
} 
522  
523 
#ifdef DEBUG

524 
s>frame_count = 0;

525 
#endif

526 
if (avctx>codec_id == CODEC_ID_MP3ADU)

527 
s>adu_mode = 1;

528 
return 0; 
529 
} 
530  
531 
/* tab[i][j] = 1.0 / (2.0 * cos(pi*(2*k+1) / 2^(6  j))) */

532  
533 
/* cos(i*pi/64) */

534  
535 
#define COS0_0 FIXHR(0.50060299823519630134/2) 
536 
#define COS0_1 FIXHR(0.50547095989754365998/2) 
537 
#define COS0_2 FIXHR(0.51544730992262454697/2) 
538 
#define COS0_3 FIXHR(0.53104259108978417447/2) 
539 
#define COS0_4 FIXHR(0.55310389603444452782/2) 
540 
#define COS0_5 FIXHR(0.58293496820613387367/2) 
541 
#define COS0_6 FIXHR(0.62250412303566481615/2) 
542 
#define COS0_7 FIXHR(0.67480834145500574602/2) 
543 
#define COS0_8 FIXHR(0.74453627100229844977/2) 
544 
#define COS0_9 FIXHR(0.83934964541552703873/2) 
545 
#define COS0_10 FIXHR(0.97256823786196069369/2) 
546 
#define COS0_11 FIXHR(1.16943993343288495515/4) 
547 
#define COS0_12 FIXHR(1.48416461631416627724/4) 
548 
#define COS0_13 FIXHR(2.05778100995341155085/8) 
549 
#define COS0_14 FIXHR(3.40760841846871878570/8) 
550 
#define COS0_15 FIXHR(10.19000812354805681150/32) 
551  
552 
#define COS1_0 FIXHR(0.50241928618815570551/2) 
553 
#define COS1_1 FIXHR(0.52249861493968888062/2) 
554 
#define COS1_2 FIXHR(0.56694403481635770368/2) 
555 
#define COS1_3 FIXHR(0.64682178335999012954/2) 
556 
#define COS1_4 FIXHR(0.78815462345125022473/2) 
557 
#define COS1_5 FIXHR(1.06067768599034747134/4) 
558 
#define COS1_6 FIXHR(1.72244709823833392782/4) 
559 
#define COS1_7 FIXHR(5.10114861868916385802/16) 
560  
561 
#define COS2_0 FIXHR(0.50979557910415916894/2) 
562 
#define COS2_1 FIXHR(0.60134488693504528054/2) 
563 
#define COS2_2 FIXHR(0.89997622313641570463/2) 
564 
#define COS2_3 FIXHR(2.56291544774150617881/8) 
565  
566 
#define COS3_0 FIXHR(0.54119610014619698439/2) 
567 
#define COS3_1 FIXHR(1.30656296487637652785/4) 
568  
569 
#define COS4_0 FIXHR(0.70710678118654752439/2) 
570  
571 
/* butterfly operator */

572 
#define BF(a, b, c, s)\

573 
{\ 
574 
tmp0 = tab[a] + tab[b];\ 
575 
tmp1 = tab[a]  tab[b];\ 
576 
tab[a] = tmp0;\ 
577 
tab[b] = MULH(tmp1<<(s), c);\ 
578 
} 
579  
580 
#define BF1(a, b, c, d)\

581 
{\ 
582 
BF(a, b, COS4_0, 1);\

583 
BF(c, d,COS4_0, 1);\

584 
tab[c] += tab[d];\ 
585 
} 
586  
587 
#define BF2(a, b, c, d)\

588 
{\ 
589 
BF(a, b, COS4_0, 1);\

590 
BF(c, d,COS4_0, 1);\

591 
tab[c] += tab[d];\ 
592 
tab[a] += tab[c];\ 
593 
tab[c] += tab[b];\ 
594 
tab[b] += tab[d];\ 
595 
} 
596  
597 
#define ADD(a, b) tab[a] += tab[b]

598  
599 
/* DCT32 without 1/sqrt(2) coef zero scaling. */

600 
static void dct32(int32_t *out, int32_t *tab) 
601 
{ 
602 
int tmp0, tmp1;

603  
604 
/* pass 1 */

605 
BF( 0, 31, COS0_0 , 1); 
606 
BF(15, 16, COS0_15, 5); 
607 
/* pass 2 */

608 
BF( 0, 15, COS1_0 , 1); 
609 
BF(16, 31,COS1_0 , 1); 
610 
/* pass 1 */

611 
BF( 7, 24, COS0_7 , 1); 
612 
BF( 8, 23, COS0_8 , 1); 
613 
/* pass 2 */

614 
BF( 7, 8, COS1_7 , 4); 
615 
BF(23, 24,COS1_7 , 4); 
616 
/* pass 3 */

617 
BF( 0, 7, COS2_0 , 1); 
618 
BF( 8, 15,COS2_0 , 1); 
619 
BF(16, 23, COS2_0 , 1); 
620 
BF(24, 31,COS2_0 , 1); 
621 
/* pass 1 */

622 
BF( 3, 28, COS0_3 , 1); 
623 
BF(12, 19, COS0_12, 2); 
624 
/* pass 2 */

625 
BF( 3, 12, COS1_3 , 1); 
626 
BF(19, 28,COS1_3 , 1); 
627 
/* pass 1 */

628 
BF( 4, 27, COS0_4 , 1); 
629 
BF(11, 20, COS0_11, 2); 
630 
/* pass 2 */

631 
BF( 4, 11, COS1_4 , 1); 
632 
BF(20, 27,COS1_4 , 1); 
633 
/* pass 3 */

634 
BF( 3, 4, COS2_3 , 3); 
635 
BF(11, 12,COS2_3 , 3); 
636 
BF(19, 20, COS2_3 , 3); 
637 
BF(27, 28,COS2_3 , 3); 
638 
/* pass 4 */

639 
BF( 0, 3, COS3_0 , 1); 
640 
BF( 4, 7,COS3_0 , 1); 
641 
BF( 8, 11, COS3_0 , 1); 
642 
BF(12, 15,COS3_0 , 1); 
643 
BF(16, 19, COS3_0 , 1); 
644 
BF(20, 23,COS3_0 , 1); 
645 
BF(24, 27, COS3_0 , 1); 
646 
BF(28, 31,COS3_0 , 1); 
647  
648  
649  
650 
/* pass 1 */

651 
BF( 1, 30, COS0_1 , 1); 
652 
BF(14, 17, COS0_14, 3); 
653 
/* pass 2 */

654 
BF( 1, 14, COS1_1 , 1); 
655 
BF(17, 30,COS1_1 , 1); 
656 
/* pass 1 */

657 
BF( 6, 25, COS0_6 , 1); 
658 
BF( 9, 22, COS0_9 , 1); 
659 
/* pass 2 */

660 
BF( 6, 9, COS1_6 , 2); 
661 
BF(22, 25,COS1_6 , 2); 
662 
/* pass 3 */

663 
BF( 1, 6, COS2_1 , 1); 
664 
BF( 9, 14,COS2_1 , 1); 
665 
BF(17, 22, COS2_1 , 1); 
666 
BF(25, 30,COS2_1 , 1); 
667  
668 
/* pass 1 */

669 
BF( 2, 29, COS0_2 , 1); 
670 
BF(13, 18, COS0_13, 3); 
671 
/* pass 2 */

672 
BF( 2, 13, COS1_2 , 1); 
673 
BF(18, 29,COS1_2 , 1); 
674 
/* pass 1 */

675 
BF( 5, 26, COS0_5 , 1); 
676 
BF(10, 21, COS0_10, 1); 
677 
/* pass 2 */

678 
BF( 5, 10, COS1_5 , 2); 
679 
BF(21, 26,COS1_5 , 2); 
680 
/* pass 3 */

681 
BF( 2, 5, COS2_2 , 1); 
682 
BF(10, 13,COS2_2 , 1); 
683 
BF(18, 21, COS2_2 , 1); 
684 
BF(26, 29,COS2_2 , 1); 
685 
/* pass 4 */

686 
BF( 1, 2, COS3_1 , 2); 
687 
BF( 5, 6,COS3_1 , 2); 
688 
BF( 9, 10, COS3_1 , 2); 
689 
BF(13, 14,COS3_1 , 2); 
690 
BF(17, 18, COS3_1 , 2); 
691 
BF(21, 22,COS3_1 , 2); 
692 
BF(25, 26, COS3_1 , 2); 
693 
BF(29, 30,COS3_1 , 2); 
694  
695 
/* pass 5 */

696 
BF1( 0, 1, 2, 3); 
697 
BF2( 4, 5, 6, 7); 
698 
BF1( 8, 9, 10, 11); 
699 
BF2(12, 13, 14, 15); 
700 
BF1(16, 17, 18, 19); 
701 
BF2(20, 21, 22, 23); 
702 
BF1(24, 25, 26, 27); 
703 
BF2(28, 29, 30, 31); 
704  
705 
/* pass 6 */

706  
707 
ADD( 8, 12); 
708 
ADD(12, 10); 
709 
ADD(10, 14); 
710 
ADD(14, 9); 
711 
ADD( 9, 13); 
712 
ADD(13, 11); 
713 
ADD(11, 15); 
714  
715 
out[ 0] = tab[0]; 
716 
out[16] = tab[1]; 
717 
out[ 8] = tab[2]; 
718 
out[24] = tab[3]; 
719 
out[ 4] = tab[4]; 
720 
out[20] = tab[5]; 
721 
out[12] = tab[6]; 
722 
out[28] = tab[7]; 
723 
out[ 2] = tab[8]; 
724 
out[18] = tab[9]; 
725 
out[10] = tab[10]; 
726 
out[26] = tab[11]; 
727 
out[ 6] = tab[12]; 
728 
out[22] = tab[13]; 
729 
out[14] = tab[14]; 
730 
out[30] = tab[15]; 
731  
732 
ADD(24, 28); 
733 
ADD(28, 26); 
734 
ADD(26, 30); 
735 
ADD(30, 25); 
736 
ADD(25, 29); 
737 
ADD(29, 27); 
738 
ADD(27, 31); 
739  
740 
out[ 1] = tab[16] + tab[24]; 
741 
out[17] = tab[17] + tab[25]; 
742 
out[ 9] = tab[18] + tab[26]; 
743 
out[25] = tab[19] + tab[27]; 
744 
out[ 5] = tab[20] + tab[28]; 
745 
out[21] = tab[21] + tab[29]; 
746 
out[13] = tab[22] + tab[30]; 
747 
out[29] = tab[23] + tab[31]; 
748 
out[ 3] = tab[24] + tab[20]; 
749 
out[19] = tab[25] + tab[21]; 
750 
out[11] = tab[26] + tab[22]; 
751 
out[27] = tab[27] + tab[23]; 
752 
out[ 7] = tab[28] + tab[18]; 
753 
out[23] = tab[29] + tab[19]; 
754 
out[15] = tab[30] + tab[17]; 
755 
out[31] = tab[31]; 
756 
} 
757  
758 
#if FRAC_BITS <= 15 
759  
760 
static inline int round_sample(int *sum) 
761 
{ 
762 
int sum1;

763 
sum1 = (*sum) >> OUT_SHIFT; 
764 
*sum &= (1<<OUT_SHIFT)1; 
765 
if (sum1 < OUT_MIN)

766 
sum1 = OUT_MIN; 
767 
else if (sum1 > OUT_MAX) 
768 
sum1 = OUT_MAX; 
769 
return sum1;

770 
} 
771  
772 
/* signed 16x16 > 32 multiply add accumulate */

773 
#define MACS(rt, ra, rb) MAC16(rt, ra, rb)

774  
775 
/* signed 16x16 > 32 multiply */

776 
#define MULS(ra, rb) MUL16(ra, rb)

777  
778 
#else

779  
780 
static inline int round_sample(int64_t *sum) 
781 
{ 
782 
int sum1;

783 
sum1 = (int)((*sum) >> OUT_SHIFT);

784 
*sum &= (1<<OUT_SHIFT)1; 
785 
if (sum1 < OUT_MIN)

786 
sum1 = OUT_MIN; 
787 
else if (sum1 > OUT_MAX) 
788 
sum1 = OUT_MAX; 
789 
return sum1;

790 
} 
791  
792 
# define MULS(ra, rb) MUL64(ra, rb)

793 
#endif

794  
795 
#define SUM8(sum, op, w, p) \

796 
{ \ 
797 
sum op MULS((w)[0 * 64], p[0 * 64]);\ 
798 
sum op MULS((w)[1 * 64], p[1 * 64]);\ 
799 
sum op MULS((w)[2 * 64], p[2 * 64]);\ 
800 
sum op MULS((w)[3 * 64], p[3 * 64]);\ 
801 
sum op MULS((w)[4 * 64], p[4 * 64]);\ 
802 
sum op MULS((w)[5 * 64], p[5 * 64]);\ 
803 
sum op MULS((w)[6 * 64], p[6 * 64]);\ 
804 
sum op MULS((w)[7 * 64], p[7 * 64]);\ 
805 
} 
806  
807 
#define SUM8P2(sum1, op1, sum2, op2, w1, w2, p) \

808 
{ \ 
809 
int tmp;\

810 
tmp = p[0 * 64];\ 
811 
sum1 op1 MULS((w1)[0 * 64], tmp);\ 
812 
sum2 op2 MULS((w2)[0 * 64], tmp);\ 
813 
tmp = p[1 * 64];\ 
814 
sum1 op1 MULS((w1)[1 * 64], tmp);\ 
815 
sum2 op2 MULS((w2)[1 * 64], tmp);\ 
816 
tmp = p[2 * 64];\ 
817 
sum1 op1 MULS((w1)[2 * 64], tmp);\ 
818 
sum2 op2 MULS((w2)[2 * 64], tmp);\ 
819 
tmp = p[3 * 64];\ 
820 
sum1 op1 MULS((w1)[3 * 64], tmp);\ 
821 
sum2 op2 MULS((w2)[3 * 64], tmp);\ 
822 
tmp = p[4 * 64];\ 
823 
sum1 op1 MULS((w1)[4 * 64], tmp);\ 
824 
sum2 op2 MULS((w2)[4 * 64], tmp);\ 
825 
tmp = p[5 * 64];\ 
826 
sum1 op1 MULS((w1)[5 * 64], tmp);\ 
827 
sum2 op2 MULS((w2)[5 * 64], tmp);\ 
828 
tmp = p[6 * 64];\ 
829 
sum1 op1 MULS((w1)[6 * 64], tmp);\ 
830 
sum2 op2 MULS((w2)[6 * 64], tmp);\ 
831 
tmp = p[7 * 64];\ 
832 
sum1 op1 MULS((w1)[7 * 64], tmp);\ 
833 
sum2 op2 MULS((w2)[7 * 64], tmp);\ 
834 
} 
835  
836 
void ff_mpa_synth_init(MPA_INT *window)

837 
{ 
838 
int i;

839  
840 
/* max = 18760, max sum over all 16 coefs : 44736 */

841 
for(i=0;i<257;i++) { 
842 
int v;

843 
v = ff_mpa_enwindow[i]; 
844 
#if WFRAC_BITS < 16 
845 
v = (v + (1 << (16  WFRAC_BITS  1))) >> (16  WFRAC_BITS); 
846 
#endif

847 
window[i] = v; 
848 
if ((i & 63) != 0) 
849 
v = v; 
850 
if (i != 0) 
851 
window[512  i] = v;

852 
} 
853 
} 
854  
855 
/* 32 sub band synthesis filter. Input: 32 sub band samples, Output:

856 
32 samples. */

857 
/* XXX: optimize by avoiding ring buffer usage */

858 
void ff_mpa_synth_filter(MPA_INT *synth_buf_ptr, int *synth_buf_offset, 
859 
MPA_INT *window, int *dither_state,

860 
OUT_INT *samples, int incr,

861 
int32_t sb_samples[SBLIMIT]) 
862 
{ 
863 
int32_t tmp[32];

864 
register MPA_INT *synth_buf;

865 
register const MPA_INT *w, *w2, *p; 
866 
int j, offset, v;

867 
OUT_INT *samples2; 
868 
#if FRAC_BITS <= 15 
869 
int sum, sum2;

870 
#else

871 
int64_t sum, sum2; 
872 
#endif

873  
874 
dct32(tmp, sb_samples); 
875  
876 
offset = *synth_buf_offset; 
877 
synth_buf = synth_buf_ptr + offset; 
878  
879 
for(j=0;j<32;j++) { 
880 
v = tmp[j]; 
881 
#if FRAC_BITS <= 15 
882 
/* NOTE: can cause a loss in precision if very high amplitude

883 
sound */

884 
v = av_clip_int16(v); 
885 
#endif

886 
synth_buf[j] = v; 
887 
} 
888 
/* copy to avoid wrap */

889 
memcpy(synth_buf + 512, synth_buf, 32 * sizeof(MPA_INT)); 
890  
891 
samples2 = samples + 31 * incr;

892 
w = window; 
893 
w2 = window + 31;

894  
895 
sum = *dither_state; 
896 
p = synth_buf + 16;

897 
SUM8(sum, +=, w, p); 
898 
p = synth_buf + 48;

899 
SUM8(sum, =, w + 32, p);

900 
*samples = round_sample(&sum); 
901 
samples += incr; 
902 
w++; 
903  
904 
/* we calculate two samples at the same time to avoid one memory

905 
access per two sample */

906 
for(j=1;j<16;j++) { 
907 
sum2 = 0;

908 
p = synth_buf + 16 + j;

909 
SUM8P2(sum, +=, sum2, =, w, w2, p); 
910 
p = synth_buf + 48  j;

911 
SUM8P2(sum, =, sum2, =, w + 32, w2 + 32, p); 
912  
913 
*samples = round_sample(&sum); 
914 
samples += incr; 
915 
sum += sum2; 
916 
*samples2 = round_sample(&sum); 
917 
samples2 = incr; 
918 
w++; 
919 
w2; 
920 
} 
921  
922 
p = synth_buf + 32;

923 
SUM8(sum, =, w + 32, p);

924 
*samples = round_sample(&sum); 
925 
*dither_state= sum; 
926  
927 
offset = (offset  32) & 511; 
928 
*synth_buf_offset = offset; 
929 
} 
930  
931 
#define C3 FIXHR(0.86602540378443864676/2) 
932  
933 
/* 0.5 / cos(pi*(2*i+1)/36) */

934 
static const int icos36[9] = { 
935 
FIXR(0.50190991877167369479), 
936 
FIXR(0.51763809020504152469), //0 
937 
FIXR(0.55168895948124587824), 
938 
FIXR(0.61038729438072803416), 
939 
FIXR(0.70710678118654752439), //1 
940 
FIXR(0.87172339781054900991), 
941 
FIXR(1.18310079157624925896), 
942 
FIXR(1.93185165257813657349), //2 
943 
FIXR(5.73685662283492756461), 
944 
}; 
945  
946 
/* 0.5 / cos(pi*(2*i+1)/36) */

947 
static const int icos36h[9] = { 
948 
FIXHR(0.50190991877167369479/2), 
949 
FIXHR(0.51763809020504152469/2), //0 
950 
FIXHR(0.55168895948124587824/2), 
951 
FIXHR(0.61038729438072803416/2), 
952 
FIXHR(0.70710678118654752439/2), //1 
953 
FIXHR(0.87172339781054900991/2), 
954 
FIXHR(1.18310079157624925896/4), 
955 
FIXHR(1.93185165257813657349/4), //2 
956 
// FIXHR(5.73685662283492756461),

957 
}; 
958  
959 
/* 12 points IMDCT. We compute it "by hand" by factorizing obvious

960 
cases. */

961 
static void imdct12(int *out, int *in) 
962 
{ 
963 
int in0, in1, in2, in3, in4, in5, t1, t2;

964  
965 
in0= in[0*3]; 
966 
in1= in[1*3] + in[0*3]; 
967 
in2= in[2*3] + in[1*3]; 
968 
in3= in[3*3] + in[2*3]; 
969 
in4= in[4*3] + in[3*3]; 
970 
in5= in[5*3] + in[4*3]; 
971 
in5 += in3; 
972 
in3 += in1; 
973  
974 
in2= MULH(2*in2, C3);

975 
in3= MULH(4*in3, C3);

976  
977 
t1 = in0  in4; 
978 
t2 = MULH(2*(in1  in5), icos36h[4]); 
979  
980 
out[ 7]=

981 
out[10]= t1 + t2;

982 
out[ 1]=

983 
out[ 4]= t1  t2;

984  
985 
in0 += in4>>1;

986 
in4 = in0 + in2; 
987 
in5 += 2*in1;

988 
in1 = MULH(in5 + in3, icos36h[1]);

989 
out[ 8]=

990 
out[ 9]= in4 + in1;

991 
out[ 2]=

992 
out[ 3]= in4  in1;

993  
994 
in0 = in2; 
995 
in5 = MULH(2*(in5  in3), icos36h[7]); 
996 
out[ 0]=

997 
out[ 5]= in0  in5;

998 
out[ 6]=

999 
out[11]= in0 + in5;

1000 
} 
1001  
1002 
/* cos(pi*i/18) */

1003 
#define C1 FIXHR(0.98480775301220805936/2) 
1004 
#define C2 FIXHR(0.93969262078590838405/2) 
1005 
#define C3 FIXHR(0.86602540378443864676/2) 
1006 
#define C4 FIXHR(0.76604444311897803520/2) 
1007 
#define C5 FIXHR(0.64278760968653932632/2) 
1008 
#define C6 FIXHR(0.5/2) 
1009 
#define C7 FIXHR(0.34202014332566873304/2) 
1010 
#define C8 FIXHR(0.17364817766693034885/2) 
1011  
1012  
1013 
/* using Lee like decomposition followed by hand coded 9 points DCT */

1014 
static void imdct36(int *out, int *buf, int *in, int *win) 
1015 
{ 
1016 
int i, j, t0, t1, t2, t3, s0, s1, s2, s3;

1017 
int tmp[18], *tmp1, *in1; 
1018  
1019 
for(i=17;i>=1;i) 
1020 
in[i] += in[i1];

1021 
for(i=17;i>=3;i=2) 
1022 
in[i] += in[i2];

1023  
1024 
for(j=0;j<2;j++) { 
1025 
tmp1 = tmp + j; 
1026 
in1 = in + j; 
1027 
#if 0

1028 
//more accurate but slower

1029 
int64_t t0, t1, t2, t3;

1030 
t2 = in1[2*4] + in1[2*8]  in1[2*2];

1031 

1032 
t3 = (in1[2*0] + (int64_t)(in1[2*6]>>1))<<32;

1033 
t1 = in1[2*0]  in1[2*6];

1034 
tmp1[ 6] = t1  (t2>>1);

1035 
tmp1[16] = t1 + t2;

1036 

1037 
t0 = MUL64(2*(in1[2*2] + in1[2*4]), C2);

1038 
t1 = MUL64( in1[2*4]  in1[2*8] , 2*C8);

1039 
t2 = MUL64(2*(in1[2*2] + in1[2*8]), C4);

1040 

1041 
tmp1[10] = (t3  t0  t2) >> 32;

1042 
tmp1[ 2] = (t3 + t0 + t1) >> 32;

1043 
tmp1[14] = (t3 + t2  t1) >> 32;

1044 

1045 
tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7]  in1[2*1]), C3);

1046 
t2 = MUL64(2*(in1[2*1] + in1[2*5]), C1);

1047 
t3 = MUL64( in1[2*5]  in1[2*7] , 2*C7);

1048 
t0 = MUL64(2*in1[2*3], C3);

1049 

1050 
t1 = MUL64(2*(in1[2*1] + in1[2*7]), C5);

1051 

1052 
tmp1[ 0] = (t2 + t3 + t0) >> 32;

1053 
tmp1[12] = (t2 + t1  t0) >> 32;

1054 
tmp1[ 8] = (t3  t1  t0) >> 32;

1055 
#else

1056 
t2 = in1[2*4] + in1[2*8]  in1[2*2]; 
1057  
1058 
t3 = in1[2*0] + (in1[2*6]>>1); 
1059 
t1 = in1[2*0]  in1[2*6]; 
1060 
tmp1[ 6] = t1  (t2>>1); 
1061 
tmp1[16] = t1 + t2;

1062  
1063 
t0 = MULH(2*(in1[2*2] + in1[2*4]), C2); 
1064 
t1 = MULH( in1[2*4]  in1[2*8] , 2*C8); 
1065 
t2 = MULH(2*(in1[2*2] + in1[2*8]), C4); 
1066  
1067 
tmp1[10] = t3  t0  t2;

1068 
tmp1[ 2] = t3 + t0 + t1;

1069 
tmp1[14] = t3 + t2  t1;

1070  
1071 
tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7]  in1[2*1]), C3); 
1072 
t2 = MULH(2*(in1[2*1] + in1[2*5]), C1); 
1073 
t3 = MULH( in1[2*5]  in1[2*7] , 2*C7); 
1074 
t0 = MULH(2*in1[2*3], C3); 
1075  
1076 
t1 = MULH(2*(in1[2*1] + in1[2*7]), C5); 
1077  
1078 
tmp1[ 0] = t2 + t3 + t0;

1079 
tmp1[12] = t2 + t1  t0;

1080 
tmp1[ 8] = t3  t1  t0;

1081 
#endif

1082 
} 
1083  
1084 
i = 0;

1085 
for(j=0;j<4;j++) { 
1086 
t0 = tmp[i]; 
1087 
t1 = tmp[i + 2];

1088 
s0 = t1 + t0; 
1089 
s2 = t1  t0; 
1090  
1091 
t2 = tmp[i + 1];

1092 
t3 = tmp[i + 3];

1093 
s1 = MULH(2*(t3 + t2), icos36h[j]);

1094 
s3 = MULL(t3  t2, icos36[8  j]);

1095  
1096 
t0 = s0 + s1; 
1097 
t1 = s0  s1; 
1098 
out[(9 + j)*SBLIMIT] = MULH(t1, win[9 + j]) + buf[9 + j]; 
1099 
out[(8  j)*SBLIMIT] = MULH(t1, win[8  j]) + buf[8  j]; 
1100 
buf[9 + j] = MULH(t0, win[18 + 9 + j]); 
1101 
buf[8  j] = MULH(t0, win[18 + 8  j]); 
1102  
1103 
t0 = s2 + s3; 
1104 
t1 = s2  s3; 
1105 
out[(9 + 8  j)*SBLIMIT] = MULH(t1, win[9 + 8  j]) + buf[9 + 8  j]; 
1106 
out[( j)*SBLIMIT] = MULH(t1, win[ j]) + buf[ j]; 
1107 
buf[9 + 8  j] = MULH(t0, win[18 + 9 + 8  j]); 
1108 
buf[ + j] = MULH(t0, win[18 + j]);

1109 
i += 4;

1110 
} 
1111  
1112 
s0 = tmp[16];

1113 
s1 = MULH(2*tmp[17], icos36h[4]); 
1114 
t0 = s0 + s1; 
1115 
t1 = s0  s1; 
1116 
out[(9 + 4)*SBLIMIT] = MULH(t1, win[9 + 4]) + buf[9 + 4]; 
1117 
out[(8  4)*SBLIMIT] = MULH(t1, win[8  4]) + buf[8  4]; 
1118 
buf[9 + 4] = MULH(t0, win[18 + 9 + 4]); 
1119 
buf[8  4] = MULH(t0, win[18 + 8  4]); 
1120 
} 
1121  
1122 
/* return the number of decoded frames */

1123 
static int mp_decode_layer1(MPADecodeContext *s) 
1124 
{ 
1125 
int bound, i, v, n, ch, j, mant;

1126 
uint8_t allocation[MPA_MAX_CHANNELS][SBLIMIT]; 
1127 
uint8_t scale_factors[MPA_MAX_CHANNELS][SBLIMIT]; 
1128  
1129 
if (s>mode == MPA_JSTEREO)

1130 
bound = (s>mode_ext + 1) * 4; 
1131 
else

1132 
bound = SBLIMIT; 
1133  
1134 
/* allocation bits */

1135 
for(i=0;i<bound;i++) { 
1136 
for(ch=0;ch<s>nb_channels;ch++) { 
1137 
allocation[ch][i] = get_bits(&s>gb, 4);

1138 
} 
1139 
} 
1140 
for(i=bound;i<SBLIMIT;i++) {

1141 
allocation[0][i] = get_bits(&s>gb, 4); 
1142 
} 
1143  
1144 
/* scale factors */

1145 
for(i=0;i<bound;i++) { 
1146 
for(ch=0;ch<s>nb_channels;ch++) { 
1147 
if (allocation[ch][i])

1148 
scale_factors[ch][i] = get_bits(&s>gb, 6);

1149 
} 
1150 
} 
1151 
for(i=bound;i<SBLIMIT;i++) {

1152 
if (allocation[0][i]) { 
1153 
scale_factors[0][i] = get_bits(&s>gb, 6); 
1154 
scale_factors[1][i] = get_bits(&s>gb, 6); 
1155 
} 
1156 
} 
1157  
1158 
/* compute samples */

1159 
for(j=0;j<12;j++) { 
1160 
for(i=0;i<bound;i++) { 
1161 
for(ch=0;ch<s>nb_channels;ch++) { 
1162 
n = allocation[ch][i]; 
1163 
if (n) {

1164 
mant = get_bits(&s>gb, n + 1);

1165 
v = l1_unscale(n, mant, scale_factors[ch][i]); 
1166 
} else {

1167 
v = 0;

1168 
} 
1169 
s>sb_samples[ch][j][i] = v; 
1170 
} 
1171 
} 
1172 
for(i=bound;i<SBLIMIT;i++) {

1173 
n = allocation[0][i];

1174 
if (n) {

1175 
mant = get_bits(&s>gb, n + 1);

1176 
v = l1_unscale(n, mant, scale_factors[0][i]);

1177 
s>sb_samples[0][j][i] = v;

1178 
v = l1_unscale(n, mant, scale_factors[1][i]);

1179 
s>sb_samples[1][j][i] = v;

1180 
} else {

1181 
s>sb_samples[0][j][i] = 0; 
1182 
s>sb_samples[1][j][i] = 0; 
1183 
} 
1184 
} 
1185 
} 
1186 
return 12; 
1187 
} 
1188  
1189 
static int mp_decode_layer2(MPADecodeContext *s) 
1190 
{ 
1191 
int sblimit; /* number of used subbands */ 
1192 
const unsigned char *alloc_table; 
1193 
int table, bit_alloc_bits, i, j, ch, bound, v;

1194 
unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT]; 
1195 
unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT]; 
1196 
unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3], *sf; 
1197 
int scale, qindex, bits, steps, k, l, m, b;

1198  
1199 
/* select decoding table */

1200 
table = ff_mpa_l2_select_table(s>bit_rate / 1000, s>nb_channels,

1201 
s>sample_rate, s>lsf); 
1202 
sblimit = ff_mpa_sblimit_table[table]; 
1203 
alloc_table = ff_mpa_alloc_tables[table]; 
1204  
1205 
if (s>mode == MPA_JSTEREO)

1206 
bound = (s>mode_ext + 1) * 4; 
1207 
else

1208 
bound = sblimit; 
1209  
1210 
dprintf(s>avctx, "bound=%d sblimit=%d\n", bound, sblimit);

1211  
1212 
/* sanity check */

1213 
if( bound > sblimit ) bound = sblimit;

1214  
1215 
/* parse bit allocation */

1216 
j = 0;

1217 
for(i=0;i<bound;i++) { 
1218 
bit_alloc_bits = alloc_table[j]; 
1219 
for(ch=0;ch<s>nb_channels;ch++) { 
1220 
bit_alloc[ch][i] = get_bits(&s>gb, bit_alloc_bits); 
1221 
} 
1222 
j += 1 << bit_alloc_bits;

1223 
} 
1224 
for(i=bound;i<sblimit;i++) {

1225 
bit_alloc_bits = alloc_table[j]; 
1226 
v = get_bits(&s>gb, bit_alloc_bits); 
1227 
bit_alloc[0][i] = v;

1228 
bit_alloc[1][i] = v;

1229 
j += 1 << bit_alloc_bits;

1230 
} 
1231  
1232 
#ifdef DEBUG

1233 
{ 
1234 
for(ch=0;ch<s>nb_channels;ch++) { 
1235 
for(i=0;i<sblimit;i++) 
1236 
dprintf(s>avctx, " %d", bit_alloc[ch][i]);

1237 
dprintf(s>avctx, "\n");

1238 
} 
1239 
} 
1240 
#endif

1241  
1242 
/* scale codes */

1243 
for(i=0;i<sblimit;i++) { 
1244 
for(ch=0;ch<s>nb_channels;ch++) { 
1245 
if (bit_alloc[ch][i])

1246 
scale_code[ch][i] = get_bits(&s>gb, 2);

1247 
} 
1248 
} 
1249  
1250 
/* scale factors */

1251 
for(i=0;i<sblimit;i++) { 
1252 
for(ch=0;ch<s>nb_channels;ch++) { 
1253 
if (bit_alloc[ch][i]) {

1254 
sf = scale_factors[ch][i]; 
1255 
switch(scale_code[ch][i]) {

1256 
default:

1257 
case 0: 
1258 
sf[0] = get_bits(&s>gb, 6); 
1259 
sf[1] = get_bits(&s>gb, 6); 
1260 
sf[2] = get_bits(&s>gb, 6); 
1261 
break;

1262 
case 2: 
1263 
sf[0] = get_bits(&s>gb, 6); 
1264 
sf[1] = sf[0]; 
1265 
sf[2] = sf[0]; 
1266 
break;

1267 
case 1: 
1268 
sf[0] = get_bits(&s>gb, 6); 
1269 
sf[2] = get_bits(&s>gb, 6); 
1270 
sf[1] = sf[0]; 
1271 
break;

1272 
case 3: 
1273 
sf[0] = get_bits(&s>gb, 6); 
1274 
sf[2] = get_bits(&s>gb, 6); 
1275 
sf[1] = sf[2]; 
1276 
break;

1277 
} 
1278 
} 
1279 
} 
1280 
} 
1281  
1282 
#ifdef DEBUG

1283 
for(ch=0;ch<s>nb_channels;ch++) { 
1284 
for(i=0;i<sblimit;i++) { 
1285 
if (bit_alloc[ch][i]) {

1286 
sf = scale_factors[ch][i]; 
1287 
dprintf(s>avctx, " %d %d %d", sf[0], sf[1], sf[2]); 
1288 
} else {

1289 
dprintf(s>avctx, " ");

1290 
} 
1291 
} 
1292 
dprintf(s>avctx, "\n");

1293 
} 
1294 
#endif

1295  
1296 
/* samples */

1297 
for(k=0;k<3;k++) { 
1298 
for(l=0;l<12;l+=3) { 
1299 
j = 0;

1300 
for(i=0;i<bound;i++) { 
1301 
bit_alloc_bits = alloc_table[j]; 
1302 
for(ch=0;ch<s>nb_channels;ch++) { 
1303 
b = bit_alloc[ch][i]; 
1304 
if (b) {

1305 
scale = scale_factors[ch][i][k]; 
1306 
qindex = alloc_table[j+b]; 
1307 
bits = ff_mpa_quant_bits[qindex]; 
1308 
if (bits < 0) { 
1309 
/* 3 values at the same time */

1310 
v = get_bits(&s>gb, bits); 
1311 
steps = ff_mpa_quant_steps[qindex]; 
1312 
s>sb_samples[ch][k * 12 + l + 0][i] = 
1313 
l2_unscale_group(steps, v % steps, scale); 
1314 
v = v / steps; 
1315 
s>sb_samples[ch][k * 12 + l + 1][i] = 
1316 
l2_unscale_group(steps, v % steps, scale); 
1317 
v = v / steps; 
1318 
s>sb_samples[ch][k * 12 + l + 2][i] = 
1319 
l2_unscale_group(steps, v, scale); 
1320 
} else {

1321 
for(m=0;m<3;m++) { 
1322 
v = get_bits(&s>gb, bits); 
1323 
v = l1_unscale(bits  1, v, scale);

1324 
s>sb_samples[ch][k * 12 + l + m][i] = v;

1325 
} 
1326 
} 
1327 
} else {

1328 
s>sb_samples[ch][k * 12 + l + 0][i] = 0; 
1329 
s>sb_samples[ch][k * 12 + l + 1][i] = 0; 
1330 
s>sb_samples[ch][k * 12 + l + 2][i] = 0; 
1331 
} 
1332 
} 
1333 
/* next subband in alloc table */

1334 
j += 1 << bit_alloc_bits;

1335 
} 
1336 
/* XXX: find a way to avoid this duplication of code */

1337 
for(i=bound;i<sblimit;i++) {

1338 
bit_alloc_bits = alloc_table[j]; 
1339 
b = bit_alloc[0][i];

1340 
if (b) {

1341 
int mant, scale0, scale1;

1342 
scale0 = scale_factors[0][i][k];

1343 
scale1 = scale_factors[1][i][k];

1344 
qindex = alloc_table[j+b]; 
1345 
bits = ff_mpa_quant_bits[qindex]; 
1346 
if (bits < 0) { 
1347 
/* 3 values at the same time */

1348 
v = get_bits(&s>gb, bits); 
1349 
steps = ff_mpa_quant_steps[qindex]; 
1350 
mant = v % steps; 
1351 
v = v / steps; 
1352 
s>sb_samples[0][k * 12 + l + 0][i] = 
1353 
l2_unscale_group(steps, mant, scale0); 
1354 
s>sb_samples[1][k * 12 + l + 0][i] = 
1355 
l2_unscale_group(steps, mant, scale1); 
1356 
mant = v % steps; 
1357 
v = v / steps; 
1358 
s>sb_samples[0][k * 12 + l + 1][i] = 
1359 
l2_unscale_group(steps, mant, scale0); 
1360 
s>sb_samples[1][k * 12 + l + 1][i] = 
1361 
l2_unscale_group(steps, mant, scale1); 
1362 
s>sb_samples[0][k * 12 + l + 2][i] = 
1363 
l2_unscale_group(steps, v, scale0); 
1364 
s>sb_samples[1][k * 12 + l + 2][i] = 
1365 
l2_unscale_group(steps, v, scale1); 
1366 
} else {

1367 
for(m=0;m<3;m++) { 
1368 
mant = get_bits(&s>gb, bits); 
1369 
s>sb_samples[0][k * 12 + l + m][i] = 
1370 
l1_unscale(bits  1, mant, scale0);

1371 
s>sb_samples[1][k * 12 + l + m][i] = 
1372 
l1_unscale(bits  1, mant, scale1);

1373 
} 
1374 
} 
1375 
} else {

1376 
s>sb_samples[0][k * 12 + l + 0][i] = 0; 
1377 
s>sb_samples[0][k * 12 + l + 1][i] = 0; 
1378 
s>sb_samples[0][k * 12 + l + 2][i] = 0; 
1379 
s>sb_samples[1][k * 12 + l + 0][i] = 0; 
1380 
s>sb_samples[1][k * 12 + l + 1][i] = 0; 
1381 
s>sb_samples[1][k * 12 + l + 2][i] = 0; 
1382 
} 
1383 
/* next subband in alloc table */

1384 
j += 1 << bit_alloc_bits;

1385 
} 
1386 
/* fill remaining samples to zero */

1387 
for(i=sblimit;i<SBLIMIT;i++) {

1388 
for(ch=0;ch<s>nb_channels;ch++) { 
1389 
s>sb_samples[ch][k * 12 + l + 0][i] = 0; 
1390 
s>sb_samples[ch][k * 12 + l + 1][i] = 0; 
1391 
s>sb_samples[ch][k * 12 + l + 2][i] = 0; 
1392 
} 
1393 
} 
1394 
} 
1395 
} 
1396 
return 3 * 12; 
1397 
} 
1398  
1399 
static inline void lsf_sf_expand(int *slen, 
1400 
int sf, int n1, int n2, int n3) 
1401 
{ 
1402 
if (n3) {

1403 
slen[3] = sf % n3;

1404 
sf /= n3; 
1405 
} else {

1406 
slen[3] = 0; 
1407 
} 
1408 
if (n2) {

1409 
slen[2] = sf % n2;

1410 
sf /= n2; 
1411 
} else {

1412 
slen[2] = 0; 
1413 
} 
1414 
slen[1] = sf % n1;

1415 
sf /= n1; 
1416 
slen[0] = sf;

1417 
} 
1418  
1419 
static void exponents_from_scale_factors(MPADecodeContext *s, 
1420 
GranuleDef *g, 
1421 
int16_t *exponents) 
1422 
{ 
1423 
const uint8_t *bstab, *pretab;

1424 
int len, i, j, k, l, v0, shift, gain, gains[3]; 
1425 
int16_t *exp_ptr; 
1426  
1427 
exp_ptr = exponents; 
1428 
gain = g>global_gain  210;

1429 
shift = g>scalefac_scale + 1;

1430  
1431 
bstab = band_size_long[s>sample_rate_index]; 
1432 
pretab = mpa_pretab[g>preflag]; 
1433 
for(i=0;i<g>long_end;i++) { 
1434 
v0 = gain  ((g>scale_factors[i] + pretab[i]) << shift) + 400;

1435 
len = bstab[i]; 
1436 
for(j=len;j>0;j) 
1437 
*exp_ptr++ = v0; 
1438 
} 
1439  
1440 
if (g>short_start < 13) { 
1441 
bstab = band_size_short[s>sample_rate_index]; 
1442 
gains[0] = gain  (g>subblock_gain[0] << 3); 
1443 
gains[1] = gain  (g>subblock_gain[1] << 3); 
1444 
gains[2] = gain  (g>subblock_gain[2] << 3); 
1445 
k = g>long_end; 
1446 
for(i=g>short_start;i<13;i++) { 
1447 
len = bstab[i]; 
1448 
for(l=0;l<3;l++) { 
1449 
v0 = gains[l]  (g>scale_factors[k++] << shift) + 400;

1450 
for(j=len;j>0;j) 
1451 
*exp_ptr++ = v0; 
1452 
} 
1453 
} 
1454 
} 
1455 
} 
1456  
1457 
/* handle n = 0 too */

1458 
static inline int get_bitsz(GetBitContext *s, int n) 
1459 
{ 
1460 
if (n == 0) 
1461 
return 0; 
1462 
else

1463 
return get_bits(s, n);

1464 
} 
1465  
1466  
1467 
static void switch_buffer(MPADecodeContext *s, int *pos, int *end_pos, int *end_pos2){ 
1468 
if(s>in_gb.buffer && *pos >= s>gb.size_in_bits){

1469 
s>gb= s>in_gb; 
1470 
s>in_gb.buffer=NULL;

1471 
assert((get_bits_count(&s>gb) & 7) == 0); 
1472 
skip_bits_long(&s>gb, *pos  *end_pos); 
1473 
*end_pos2= 
1474 
*end_pos= *end_pos2 + get_bits_count(&s>gb)  *pos; 
1475 
*pos= get_bits_count(&s>gb); 
1476 
} 
1477 
} 
1478  
1479 
static int huffman_decode(MPADecodeContext *s, GranuleDef *g, 
1480 
int16_t *exponents, int end_pos2)

1481 
{ 
1482 
int s_index;

1483 
int i;

1484 
int last_pos, bits_left;

1485 
VLC *vlc; 
1486 
int end_pos= FFMIN(end_pos2, s>gb.size_in_bits);

1487  
1488 
/* low frequencies (called big values) */

1489 
s_index = 0;

1490 
for(i=0;i<3;i++) { 
1491 
int j, k, l, linbits;

1492 
j = g>region_size[i]; 
1493 
if (j == 0) 
1494 
continue;

1495 
/* select vlc table */

1496 
k = g>table_select[i]; 
1497 
l = mpa_huff_data[k][0];

1498 
linbits = mpa_huff_data[k][1];

1499 
vlc = &huff_vlc[l]; 
1500  
1501 
if(!l){

1502 
memset(&g>sb_hybrid[s_index], 0, sizeof(*g>sb_hybrid)*2*j); 
1503 
s_index += 2*j;

1504 
continue;

1505 
} 
1506  
1507 
/* read huffcode and compute each couple */

1508 
for(;j>0;j) { 
1509 
int exponent, x, y, v;

1510 
int pos= get_bits_count(&s>gb);

1511  
1512 
if (pos >= end_pos){

1513 
// av_log(NULL, AV_LOG_ERROR, "pos: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);

1514 
switch_buffer(s, &pos, &end_pos, &end_pos2); 
1515 
// av_log(NULL, AV_LOG_ERROR, "new pos: %d %d\n", pos, end_pos);

1516 
if(pos >= end_pos)

1517 
break;

1518 
} 
1519 
y = get_vlc2(&s>gb, vlc>table, 7, 3); 
1520  
1521 
if(!y){

1522 
g>sb_hybrid[s_index ] = 
1523 
g>sb_hybrid[s_index+1] = 0; 
1524 
s_index += 2;

1525 
continue;

1526 
} 
1527  
1528 
exponent= exponents[s_index]; 
1529  
1530 
dprintf(s>avctx, "region=%d n=%d x=%d y=%d exp=%d\n",

1531 
i, g>region_size[i]  j, x, y, exponent); 
1532 
if(y&16){ 
1533 
x = y >> 5;

1534 
y = y & 0x0f;

1535 
if (x < 15){ 
1536 
v = expval_table[ exponent ][ x ]; 
1537 
// v = expval_table[ (exponent&3) ][ x ] >> FFMIN(0  (exponent>>2), 31);

1538 
}else{

1539 
x += get_bitsz(&s>gb, linbits); 
1540 
v = l3_unscale(x, exponent); 
1541 
} 
1542 
if (get_bits1(&s>gb))

1543 
v = v; 
1544 
g>sb_hybrid[s_index] = v; 
1545 
if (y < 15){ 
1546 
v = expval_table[ exponent ][ y ]; 
1547 
}else{

1548 
y += get_bitsz(&s>gb, linbits); 
1549 
v = l3_unscale(y, exponent); 
1550 
} 
1551 
if (get_bits1(&s>gb))

1552 
v = v; 
1553 
g>sb_hybrid[s_index+1] = v;

1554 
}else{

1555 
x = y >> 5;

1556 
y = y & 0x0f;

1557 
x += y; 
1558 
if (x < 15){ 
1559 
v = expval_table[ exponent ][ x ]; 
1560 
}else{

1561 
x += get_bitsz(&s>gb, linbits); 
1562 
v = l3_unscale(x, exponent); 
1563 
} 
1564 
if (get_bits1(&s>gb))

1565 
v = v; 
1566 
g>sb_hybrid[s_index+!!y] = v; 
1567 
g>sb_hybrid[s_index+ !y] = 0;

1568 
} 
1569 
s_index+=2;

1570 
} 
1571 
} 
1572  
1573 
/* high frequencies */

1574 
vlc = &huff_quad_vlc[g>count1table_select]; 
1575 
last_pos=0;

1576 
while (s_index <= 572) { 
1577 
int pos, code;

1578 
pos = get_bits_count(&s>gb); 
1579 
if (pos >= end_pos) {

1580 
if (pos > end_pos2 && last_pos){

1581 
/* some encoders generate an incorrect size for this

1582 
part. We must go back into the data */

1583 
s_index = 4;

1584 
skip_bits_long(&s>gb, last_pos  pos); 
1585 
av_log(NULL, AV_LOG_INFO, "overread, skip %d enddists: %d %d\n", last_pos  pos, end_pospos, end_pos2pos); 
1586 
if(s>error_resilience >= FF_ER_COMPLIANT)

1587 
s_index=0;

1588 
break;

1589 
} 
1590 
// av_log(NULL, AV_LOG_ERROR, "pos2: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);

1591 
switch_buffer(s, &pos, &end_pos, &end_pos2); 
1592 
// av_log(NULL, AV_LOG_ERROR, "new pos2: %d %d %d\n", pos, end_pos, s_index);

1593 
if(pos >= end_pos)

1594 
break;

1595 
} 
1596 
last_pos= pos; 
1597  
1598 
code = get_vlc2(&s>gb, vlc>table, vlc>bits, 1);

1599 
dprintf(s>avctx, "t=%d code=%d\n", g>count1table_select, code);

1600 
g>sb_hybrid[s_index+0]=

1601 
g>sb_hybrid[s_index+1]=

1602 
g>sb_hybrid[s_index+2]=

1603 
g>sb_hybrid[s_index+3]= 0; 
1604 
while(code){

1605 
static const int idxtab[16]={3,3,2,2,1,1,1,1,0,0,0,0,0,0,0,0}; 
1606 
int v;

1607 
int pos= s_index+idxtab[code];

1608 
code ^= 8>>idxtab[code];

1609 
v = exp_table[ exponents[pos] ]; 
1610 
// v = exp_table[ (exponents[pos]&3) ] >> FFMIN(0  (exponents[pos]>>2), 31);

1611 
if(get_bits1(&s>gb))

1612 
v = v; 
1613 
g>sb_hybrid[pos] = v; 
1614 
} 
1615 
s_index+=4;

1616 
} 
1617 
/* skip extension bits */

1618 
bits_left = end_pos2  get_bits_count(&s>gb); 
1619 
//av_log(NULL, AV_LOG_ERROR, "left:%d buf:%p\n", bits_left, s>in_gb.buffer);

1620 
if (bits_left < 0/*  bits_left > 500*/) { 
1621 
av_log(NULL, AV_LOG_ERROR, "bits_left=%d\n", bits_left); 
1622 
s_index=0;

1623 
}else if(bits_left > 0 && s>error_resilience >= FF_ER_AGGRESSIVE){ 
1624 
av_log(NULL, AV_LOG_ERROR, "bits_left=%d\n", bits_left); 
1625 
s_index=0;

1626 
} 
1627 
memset(&g>sb_hybrid[s_index], 0, sizeof(*g>sb_hybrid)*(576  s_index)); 
1628 
skip_bits_long(&s>gb, bits_left); 
1629  
1630 
i= get_bits_count(&s>gb); 
1631 
switch_buffer(s, &i, &end_pos, &end_pos2); 
1632  
1633 
return 0; 
1634 
} 
1635  
1636 
/* Reorder short blocks from bitstream order to interleaved order. It

1637 
would be faster to do it in parsing, but the code would be far more

1638 
complicated */

1639 
static void reorder_block(MPADecodeContext *s, GranuleDef *g) 
1640 
{ 
1641 
int i, j, len;

1642 
int32_t *ptr, *dst, *ptr1; 
1643 
int32_t tmp[576];

1644  
1645 
if (g>block_type != 2) 
1646 
return;

1647  
1648 
if (g>switch_point) {

1649 
if (s>sample_rate_index != 8) { 
1650 
ptr = g>sb_hybrid + 36;

1651 
} else {

1652 
ptr = g>sb_hybrid + 48;

1653 
} 
1654 
} else {

1655 
ptr = g>sb_hybrid; 
1656 
} 
1657  
1658 
for(i=g>short_start;i<13;i++) { 
1659 
len = band_size_short[s>sample_rate_index][i]; 
1660 
ptr1 = ptr; 
1661 
dst = tmp; 
1662 
for(j=len;j>0;j) { 
1663 
*dst++ = ptr[0*len];

1664 
*dst++ = ptr[1*len];

1665 
*dst++ = ptr[2*len];

1666 
ptr++; 
1667 
} 
1668 
ptr+=2*len;

1669 
memcpy(ptr1, tmp, len * 3 * sizeof(*ptr1)); 
1670 
} 
1671 
} 
1672  
1673 
#define ISQRT2 FIXR(0.70710678118654752440) 
1674  
1675 
static void compute_stereo(MPADecodeContext *s, 
1676 
GranuleDef *g0, GranuleDef *g1) 
1677 
{ 
1678 
int i, j, k, l;

1679 
int32_t v1, v2; 
1680 
int sf_max, tmp0, tmp1, sf, len, non_zero_found;

1681 
int32_t (*is_tab)[16];

1682 
int32_t *tab0, *tab1; 
1683 
int non_zero_found_short[3]; 
1684  
1685 
/* intensity stereo */

1686 
if (s>mode_ext & MODE_EXT_I_STEREO) {

1687 
if (!s>lsf) {

1688 
is_tab = is_table; 
1689 
sf_max = 7;

1690 
} else {

1691 
is_tab = is_table_lsf[g1>scalefac_compress & 1];

1692 
sf_max = 16;

1693 
} 
1694  
1695 
tab0 = g0>sb_hybrid + 576;

1696 
tab1 = g1>sb_hybrid + 576;

1697  
1698 
non_zero_found_short[0] = 0; 
1699 
non_zero_found_short[1] = 0; 
1700 
non_zero_found_short[2] = 0; 
1701 
k = (13  g1>short_start) * 3 + g1>long_end  3; 
1702 
for(i = 12;i >= g1>short_start;i) { 
1703 
/* for last band, use previous scale factor */

1704 
if (i != 11) 
1705 
k = 3;

1706 
len = band_size_short[s>sample_rate_index][i]; 
1707 
for(l=2;l>=0;l) { 
1708 
tab0 = len; 
1709 
tab1 = len; 
1710 
if (!non_zero_found_short[l]) {

1711 
/* test if non zero band. if so, stop doing istereo */

1712 
for(j=0;j<len;j++) { 
1713 
if (tab1[j] != 0) { 
1714 
non_zero_found_short[l] = 1;

1715 
goto found1;

1716 
} 
1717 
} 
1718 
sf = g1>scale_factors[k + l]; 
1719 
if (sf >= sf_max)

1720 
goto found1;

1721  
1722 
v1 = is_tab[0][sf];

1723 
v2 = is_tab[1][sf];

1724 
for(j=0;j<len;j++) { 
1725 
tmp0 = tab0[j]; 
1726 
tab0[j] = MULL(tmp0, v1); 
1727 
tab1[j] = MULL(tmp0, v2); 
1728 
} 
1729 
} else {

1730 
found1:

1731 
if (s>mode_ext & MODE_EXT_MS_STEREO) {

1732 
/* lower part of the spectrum : do ms stereo

1733 
if enabled */

1734 
for(j=0;j<len;j++) { 
1735 
tmp0 = tab0[j]; 
1736 
tmp1 = tab1[j]; 
1737 
tab0[j] = MULL(tmp0 + tmp1, ISQRT2); 
1738 
tab1[j] = MULL(tmp0  tmp1, ISQRT2); 
1739 
} 
1740 
} 
1741 
} 
1742 
} 
1743 
} 
1744  
1745 
non_zero_found = non_zero_found_short[0] 

1746 
non_zero_found_short[1] 

1747 
non_zero_found_short[2];

1748  
1749 
for(i = g1>long_end  1;i >= 0;i) { 
1750 
len = band_size_long[s>sample_rate_index][i]; 
1751 
tab0 = len; 
1752 
tab1 = len; 
1753 
/* test if non zero band. if so, stop doing istereo */

1754 
if (!non_zero_found) {

1755 
for(j=0;j<len;j++) { 
1756 
if (tab1[j] != 0) { 
1757 
non_zero_found = 1;

1758 
goto found2;

1759 
} 
1760 
} 
1761 
/* for last band, use previous scale factor */

1762 
k = (i == 21) ? 20 : i; 
1763 
sf = g1>scale_factors[k]; 
1764 
if (sf >= sf_max)

1765 
goto found2;

1766 
v1 = is_tab[0][sf];

1767 
v2 = is_tab[1][sf];

1768 
for(j=0;j<len;j++) { 
1769 
tmp0 = tab0[j]; 
1770 
tab0[j] = MULL(tmp0, v1); 
1771 
tab1[j] = MULL(tmp0, v2); 
1772 
} 
1773 
} else {

1774 
found2:

1775 
if (s>mode_ext & MODE_EXT_MS_STEREO) {

1776 
/* lower part of the spectrum : do ms stereo

1777 
if enabled */

1778 
for(j=0;j<len;j++) { 
1779 
tmp0 = tab0[j]; 
1780 
tmp1 = tab1[j]; 
1781 
tab0[j] = MULL(tmp0 + tmp1, ISQRT2); 
1782 
tab1[j] = MULL(tmp0  tmp1, ISQRT2); 
1783 
} 
1784 
} 
1785 
} 
1786 
} 
1787 
} else if (s>mode_ext & MODE_EXT_MS_STEREO) { 
1788 
/* ms stereo ONLY */

1789 
/* NOTE: the 1/sqrt(2) normalization factor is included in the

1790 
global gain */

1791 
tab0 = g0>sb_hybrid; 
1792 
tab1 = g1>sb_hybrid; 
1793 
for(i=0;i<576;i++) { 
1794 
tmp0 = tab0[i]; 
1795 
tmp1 = tab1[i]; 
1796 
tab0[i] = tmp0 + tmp1; 
1797 
tab1[i] = tmp0  tmp1; 
1798 
} 
1799 
} 
1800 
} 
1801  
1802 
static void compute_antialias_integer(MPADecodeContext *s, 
1803 
GranuleDef *g) 
1804 
{ 
1805 
int32_t *ptr, *csa; 
1806 
int n, i;

1807  
1808 
/* we antialias only "long" bands */

1809 
if (g>block_type == 2) { 
1810 
if (!g>switch_point)

1811 
return;

1812 
/* XXX: check this for 8000Hz case */

1813 
n = 1;

1814 
} else {

1815 
n = SBLIMIT  1;

1816 
} 
1817  
1818 
ptr = g>sb_hybrid + 18;

1819 
for(i = n;i > 0;i) { 
1820 
int tmp0, tmp1, tmp2;

1821 
csa = &csa_table[0][0]; 
1822 
#define INT_AA(j) \

1823 
tmp0 = ptr[1j];\

1824 
tmp1 = ptr[ j];\ 
1825 
tmp2= MULH(tmp0 + tmp1, csa[0+4*j]);\ 
1826 
ptr[1j] = 4*(tmp2  MULH(tmp1, csa[2+4*j]));\ 
1827 
ptr[ j] = 4*(tmp2 + MULH(tmp0, csa[3+4*j])); 
1828  
1829 
INT_AA(0)

1830 
INT_AA(1)

1831 
INT_AA(2)

1832 
INT_AA(3)

1833 
INT_AA(4)

1834 
INT_AA(5)

1835 
INT_AA(6)

1836 
INT_AA(7)

1837  
1838 
ptr += 18;

1839 
} 
1840 
} 
1841  
1842 
static void compute_antialias_float(MPADecodeContext *s, 
1843 
GranuleDef *g) 
1844 
{ 
1845 
int32_t *ptr; 
1846 
int n, i;

1847  
1848 
/* we antialias only "long" bands */

1849 
if (g>block_type == 2) { 
1850 
if (!g>switch_point)

1851 
return;

1852 
/* XXX: check this for 8000Hz case */

1853 
n = 1;

1854 
} else {

1855 
n = SBLIMIT  1;

1856 
} 
1857  
1858 
ptr = g>sb_hybrid + 18;

1859 
for(i = n;i > 0;i) { 
1860 
float tmp0, tmp1;

1861 
float *csa = &csa_table_float[0][0]; 
1862 
#define FLOAT_AA(j)\

1863 
tmp0= ptr[1j];\

1864 
tmp1= ptr[ j];\ 
1865 
ptr[1j] = lrintf(tmp0 * csa[0+4*j]  tmp1 * csa[1+4*j]);\ 
1866 
ptr[ j] = lrintf(tmp0 * csa[1+4*j] + tmp1 * csa[0+4*j]); 
1867  
1868 
FLOAT_AA(0)

1869 
FLOAT_AA(1)

1870 
FLOAT_AA(2)

1871 
FLOAT_AA(3)

1872 
FLOAT_AA(4)

1873 
FLOAT_AA(5)

1874 
FLOAT_AA(6)

1875 
FLOAT_AA(7)

1876  
1877 
ptr += 18;

1878 
} 
1879 
} 
1880  
1881 
static void compute_imdct(MPADecodeContext *s, 
1882 
GranuleDef *g, 
1883 
int32_t *sb_samples, 
1884 
int32_t *mdct_buf) 
1885 
{ 
1886 
int32_t *ptr, *win, *win1, *buf, *out_ptr, *ptr1; 
1887 
int32_t out2[12];

1888 
int i, j, mdct_long_end, v, sblimit;

1889  
1890 
/* find last non zero block */

1891 
ptr = g>sb_hybrid + 576;

1892 
ptr1 = g>sb_hybrid + 2 * 18; 
1893 
while (ptr >= ptr1) {

1894 
ptr = 6;

1895 
v = ptr[0]  ptr[1]  ptr[2]  ptr[3]  ptr[4]  ptr[5]; 
1896 
if (v != 0) 
1897 
break;

1898 
} 
1899 
sblimit = ((ptr  g>sb_hybrid) / 18) + 1; 
1900  
1901 
if (g>block_type == 2) { 
1902 
/* XXX: check for 8000 Hz */

1903 
if (g>switch_point)

1904 
mdct_long_end = 2;

1905 
else

1906 
mdct_long_end = 0;

1907 
} else {

1908 
mdct_long_end = sblimit; 
1909 
} 
1910  
1911 
buf = mdct_buf; 
1912 
ptr = g>sb_hybrid; 
1913 
for(j=0;j<mdct_long_end;j++) { 
1914 
/* apply window & overlap with previous buffer */

1915 
out_ptr = sb_samples + j; 
1916 
/* select window */

1917 
if (g>switch_point && j < 2) 
1918 
win1 = mdct_win[0];

1919 
else

1920 
win1 = mdct_win[g>block_type]; 
1921 
/* select frequency inversion */

1922 
win = win1 + ((4 * 36) & (j & 1)); 
1923 
imdct36(out_ptr, buf, ptr, win); 
1924 
out_ptr += 18*SBLIMIT;

1925 
ptr += 18;

1926 
buf += 18;

1927 
} 
1928 
for(j=mdct_long_end;j<sblimit;j++) {

1929 
/* select frequency inversion */

1930 
win = mdct_win[2] + ((4 * 36) & (j & 1)); 
1931 
out_ptr = sb_samples + j; 
1932  
1933 
for(i=0; i<6; i++){ 
1934 
*out_ptr = buf[i]; 
1935 
out_ptr += SBLIMIT; 
1936 
} 
1937 
imdct12(out2, ptr + 0);

1938 
for(i=0;i<6;i++) { 
1939 
*out_ptr = MULH(out2[i], win[i]) + buf[i + 6*1]; 
1940 
buf[i + 6*2] = MULH(out2[i + 6], win[i + 6]); 
1941 
out_ptr += SBLIMIT; 
1942 
} 
1943 
imdct12(out2, ptr + 1);

1944 
for(i=0;i<6;i++) { 
1945 
*out_ptr = MULH(out2[i], win[i]) + buf[i + 6*2]; 
1946 
buf[i + 6*0] = MULH(out2[i + 6], win[i + 6]); 
1947 
out_ptr += SBLIMIT; 
1948 
} 
1949 
imdct12(out2, ptr + 2);

1950 
for(i=0;i<6;i++) { 
1951 
buf[i + 6*0] = MULH(out2[i], win[i]) + buf[i + 6*0]; 
1952 
buf[i + 6*1] = MULH(out2[i + 6], win[i + 6]); 
1953 
buf[i + 6*2] = 0; 
1954 
} 
1955 
ptr += 18;

1956 
buf += 18;

1957 
} 
1958 
/* zero bands */

1959 
for(j=sblimit;j<SBLIMIT;j++) {

1960 
/* overlap */

1961 
out_ptr = sb_samples + j; 
1962 
for(i=0;i<18;i++) { 
1963 
*out_ptr = buf[i]; 
1964 
buf[i] = 0;

1965 
out_ptr += SBLIMIT; 
1966 
} 
1967 
buf += 18;

1968 
} 
1969 
} 
1970  
1971 
#if defined(DEBUG)

1972 
void sample_dump(int fnum, int32_t *tab, int n) 
1973 
{ 
1974 
static FILE *files[16], *f; 
1975 
char buf[512]; 
1976 
int i;

1977 
int32_t v; 
1978  
1979 
f = files[fnum]; 
1980 
if (!f) {

1981 
snprintf(buf, sizeof(buf), "/tmp/out%d.%s.pcm", 
1982 
fnum, 
1983 
#ifdef USE_HIGHPRECISION

1984 
"hp"

1985 
#else

1986 
"lp"

1987 
#endif

1988 
); 
1989 
f = fopen(buf, "w");

1990 
if (!f)

1991 
return;

1992 
files[fnum] = f; 
1993 
} 
1994  
1995 
if (fnum == 0) { 
1996 
static int pos = 0; 
1997 
av_log(NULL, AV_LOG_DEBUG, "pos=%d\n", pos); 
1998 
for(i=0;i<n;i++) { 
1999 
av_log(NULL, AV_LOG_DEBUG, " %0.4f", (double)tab[i] / FRAC_ONE); 
2000 
if ((i % 18) == 17) 
2001 
av_log(NULL, AV_LOG_DEBUG, "\n"); 
2002 
} 
2003 
pos += n; 
2004 
} 
2005 
for(i=0;i<n;i++) { 
2006 
/* normalize to 23 frac bits */

2007 
v = tab[i] << (23  FRAC_BITS);

2008 
fwrite(&v, 1, sizeof(int32_t), f); 
2009 
} 
2010 
} 
2011 
#endif

2012  
2013  
2014 
/* main layer3 decoding function */

2015 
static int mp_decode_layer3(MPADecodeContext *s) 
2016 
{ 
2017 
int nb_granules, main_data_begin, private_bits;

2018 
int gr, ch, blocksplit_flag, i, j, k, n, bits_pos;

2019 
GranuleDef granules[2][2], *g; 
2020 
int16_t exponents[576];

2021  
2022 
/* read side info */

2023 
if (s>lsf) {

2024 
main_data_begin = get_bits(&s>gb, 8);

2025 
private_bits = get_bits(&s>gb, s>nb_channels); 
2026 
nb_granules = 1;

2027 
} else {

2028 
main_data_begin = get_bits(&s>gb, 9);

2029 
if (s>nb_channels == 2) 
2030 
private_bits = get_bits(&s>gb, 3);

2031 
else

2032 
private_bits = get_bits(&s>gb, 5);

2033 
nb_granules = 2;

2034 
for(ch=0;ch<s>nb_channels;ch++) { 
2035 
granules[ch][0].scfsi = 0; /* all scale factors are transmitted */ 
2036 
granules[ch][1].scfsi = get_bits(&s>gb, 4); 
2037 
} 
2038 
} 
2039  
2040 
for(gr=0;gr<nb_granules;gr++) { 
2041 
for(ch=0;ch<s>nb_channels;ch++) { 
2042 
dprintf(s>avctx, "gr=%d ch=%d: side_info\n", gr, ch);

2043 
g = &granules[ch][gr]; 
2044 
g>part2_3_length = get_bits(&s>gb, 12);

2045 
g>big_values = get_bits(&s>gb, 9);

2046 
if(g>big_values > 288){ 
2047 
av_log(s>avctx, AV_LOG_ERROR, "big_values too big\n");

2048 
return 1; 
2049 
} 
2050  
2051 
g>global_gain = get_bits(&s>gb, 8);

2052 
/* if MS stereo only is selected, we precompute the

2053 
1/sqrt(2) renormalization factor */

2054 
if ((s>mode_ext & (MODE_EXT_MS_STEREO  MODE_EXT_I_STEREO)) ==

2055 
MODE_EXT_MS_STEREO) 
2056 
g>global_gain = 2;

2057 
if (s>lsf)

2058 
g>scalefac_compress = get_bits(&s>gb, 9);

2059 
else

2060 
g>scalefac_compress = get_bits(&s>gb, 4);

2061 
blocksplit_flag = get_bits1(&s>gb); 
2062 
if (blocksplit_flag) {

2063 
g>block_type = get_bits(&s>gb, 2);

2064 
if (g>block_type == 0){ 
2065 
av_log(NULL, AV_LOG_ERROR, "invalid block type\n"); 
2066 
return 1; 
2067 
} 
2068 
g>switch_point = get_bits1(&s>gb); 
2069 
for(i=0;i<2;i++) 
2070 
g>table_select[i] = get_bits(&s>gb, 5);

2071 
for(i=0;i<3;i++) 
2072 
g>subblock_gain[i] = get_bits(&s>gb, 3);

2073 
ff_init_short_region(s, g); 
2074 
} else {

2075 
int region_address1, region_address2;

2076 
g>block_type = 0;

2077 
g>switch_point = 0;

2078 
for(i=0;i<3;i++) 
2079 
g>table_select[i] = get_bits(&s>gb, 5);

2080 
/* compute huffman coded region sizes */

2081 
region_address1 = get_bits(&s>gb, 4);

2082 
region_address2 = get_bits(&s>gb, 3);

2083 
dprintf(s>avctx, "region1=%d region2=%d\n",

2084 
region_address1, region_address2); 
2085 
ff_init_long_region(s, g, region_address1, region_address2); 
2086 
} 
2087 
ff_region_offset2size(g); 
2088 
ff_compute_band_indexes(s, g); 
2089  
2090 
g>preflag = 0;

2091 
if (!s>lsf)

2092 
g>preflag = get_bits1(&s>gb); 
2093 
g>scalefac_scale = get_bits1(&s>gb); 
2094 
g>count1table_select = get_bits1(&s>gb); 
2095 
dprintf(s>avctx, "block_type=%d switch_point=%d\n",

2096 
g>block_type, g>switch_point); 
2097 
} 
2098 
} 
2099  
2100 
if (!s>adu_mode) {

2101 
const uint8_t *ptr = s>gb.buffer + (get_bits_count(&s>gb)>>3); 
2102 
assert((get_bits_count(&s>gb) & 7) == 0); 
2103 
/* now we get bits from the main_data_begin offset */

2104 
dprintf(s>avctx, "seekback: %d\n", main_data_begin);

2105 
//av_log(NULL, AV_LOG_ERROR, "backstep:%d, lastbuf:%d\n", main_data_begin, s>last_buf_size);

2106  
2107 
memcpy(s>last_buf + s>last_buf_size, ptr, EXTRABYTES); 
2108 
s>in_gb= s>gb; 
2109 
init_get_bits(&s>gb, s>last_buf, s>last_buf_size*8);

2110 
skip_bits_long(&s>gb, 8*(s>last_buf_size  main_data_begin));

2111 
} 
2112  
2113 
for(gr=0;gr<nb_granules;gr++) { 
2114 
for(ch=0;ch<s>nb_channels;ch++) { 
2115 
g = &granules[ch][gr]; 
2116 
if(get_bits_count(&s>gb)<0){ 
2117 
av_log(NULL, AV_LOG_ERROR, "mdb:%d, lastbuf:%d skipping granule %d\n", 
2118 
main_data_begin, s>last_buf_size, gr); 
2119 
skip_bits_long(&s>gb, g>part2_3_length); 
2120 
memset(g>sb_hybrid, 0, sizeof(g>sb_hybrid)); 
2121 
if(get_bits_count(&s>gb) >= s>gb.size_in_bits && s>in_gb.buffer){

2122 
skip_bits_long(&s>in_gb, get_bits_count(&s>gb)  s>gb.size_in_bits); 
2123 
s>gb= s>in_gb; 
2124 
s>in_gb.buffer=NULL;

2125 
} 
2126 
continue;

2127 
} 
2128  
2129 
bits_pos = get_bits_count(&s>gb); 
2130  
2131 
if (!s>lsf) {

2132 
uint8_t *sc; 
2133 
int slen, slen1, slen2;

2134  
2135 
/* MPEG1 scale factors */

2136 
slen1 = slen_table[0][g>scalefac_compress];

2137 
slen2 = slen_table[1][g>scalefac_compress];

2138 
dprintf(s>avctx, "slen1=%d slen2=%d\n", slen1, slen2);

2139 
if (g>block_type == 2) { 
2140 
n = g>switch_point ? 17 : 18; 
2141 
j = 0;

2142 
if(slen1){

2143 
for(i=0;i<n;i++) 
2144 
g>scale_factors[j++] = get_bits(&s>gb, slen1); 
2145 
}else{

2146 
for(i=0;i<n;i++) 
2147 
g>scale_factors[j++] = 0;

2148 
} 
2149 
if(slen2){

2150 
for(i=0;i<18;i++) 
2151 
g>scale_factors[j++] = get_bits(&s>gb, slen2); 
2152 
for(i=0;i<3;i++) 
2153 
g>scale_factors[j++] = 0;

2154 
}else{

2155 
for(i=0;i<21;i++) 
2156 
g>scale_factors[j++] = 0;

2157 
} 
2158 
} else {

2159 
sc = granules[ch][0].scale_factors;

2160 
j = 0;

2161 
for(k=0;k<4;k++) { 
2162 
n = (k == 0 ? 6 : 5); 
2163 
if ((g>scfsi & (0x8 >> k)) == 0) { 
2164 
slen = (k < 2) ? slen1 : slen2;

2165 
if(slen){

2166 
for(i=0;i<n;i++) 
2167 
g>scale_factors[j++] = get_bits(&s>gb, slen); 
2168 
}else{

2169 
for(i=0;i<n;i++) 
2170 
g>scale_factors[j++] = 0;

2171 
} 
2172 
} else {

2173 
/* simply copy from last granule */

2174 
for(i=0;i<n;i++) { 
2175 
g>scale_factors[j] = sc[j]; 
2176 
j++; 
2177 
} 
2178 
} 
2179 
} 
2180 
g>scale_factors[j++] = 0;

2181 
} 
2182 
#if defined(DEBUG)

2183 
{ 
2184 
dprintf(s>avctx, "scfsi=%x gr=%d ch=%d scale_factors:\n",

2185 
g>scfsi, gr, ch); 
2186 
for(i=0;i<j;i++) 
2187 
dprintf(s>avctx, " %d", g>scale_factors[i]);

2188 
dprintf(s>avctx, "\n");

2189 
} 
2190 
#endif

2191 
} else {

2192 
int tindex, tindex2, slen[4], sl, sf; 
2193  
2194 
/* LSF scale factors */

2195 
if (g>block_type == 2) { 
2196 
tindex = g>switch_point ? 2 : 1; 
2197 
} else {

2198 
tindex = 0;

2199 
} 
2200 
sf = g>scalefac_compress; 
2201 
if ((s>mode_ext & MODE_EXT_I_STEREO) && ch == 1) { 
2202 
/* intensity stereo case */

2203 
sf >>= 1;

2204 
if (sf < 180) { 
2205 
lsf_sf_expand(slen, sf, 6, 6, 0); 
2206 
tindex2 = 3;

2207 
} else if (sf < 244) { 
2208 
lsf_sf_expand(slen, sf  180, 4, 4, 0); 
2209 
tindex2 = 4;

2210 
} else {

2211 
lsf_sf_expand(slen, sf  244, 3, 0, 0); 
2212 
tindex2 = 5;

2213 
} 
2214 
} else {

2215 
/* normal case */

2216 
if (sf < 400) { 
2217 
lsf_sf_expand(slen, sf, 5, 4, 4); 
2218 
tindex2 = 0;

2219 
} else if (sf < 500) { 
2220 
lsf_sf_expand(slen, sf  400, 5, 4, 0); 
2221 
tindex2 = 1;

2222 
} else {

2223 
lsf_sf_expand(slen, sf  500, 3, 0, 0); 
2224 
tindex2 = 2;

2225 
g>preflag = 1;

2226 
} 
2227 
} 
2228  
2229 
j = 0;

2230 
for(k=0;k<4;k++) { 
2231 
n = lsf_nsf_table[tindex2][tindex][k]; 
2232 
sl = slen[k]; 
2233 
if(sl){

2234 
for(i=0;i<n;i++) 
2235 
g>scale_factors[j++] = get_bits(&s>gb, sl); 
2236 
}else{

2237 
for(i=0;i<n;i++) 
2238 
g>scale_factors[j++] = 0;

2239 
} 
2240 
} 
2241 
/* XXX: should compute exact size */

2242 
for(;j<40;j++) 
2243 
g>scale_factors[j] = 0;

2244 
#if defined(DEBUG)

2245 
{ 
2246 
dprintf(s>avctx, "gr=%d ch=%d scale_factors:\n",

2247 
gr, ch); 
2248 
for(i=0;i<40;i++) 
2249 
dprintf(s>avctx, " %d", g>scale_factors[i]);

2250 
dprintf(s>avctx, "\n");

2251 
} 
2252 
#endif

2253 
} 
2254  
2255 
exponents_from_scale_factors(s, g, exponents); 
2256  
2257 
/* read Huffman coded residue */

2258 
huffman_decode(s, g, exponents, bits_pos + g>part2_3_length); 
2259 
#if defined(DEBUG)

2260 
sample_dump(0, g>sb_hybrid, 576); 
2261 
#endif

2262 
} /* ch */

2263  
2264 
if (s>nb_channels == 2) 
2265 
compute_stereo(s, &granules[0][gr], &granules[1][gr]); 
2266  
2267 
for(ch=0;ch<s>nb_channels;ch++) { 
2268 
g = &granules[ch][gr]; 
2269  
2270 
reorder_block(s, g); 
2271 
#if defined(DEBUG)

2272 
sample_dump(0, g>sb_hybrid, 576); 
2273 
#endif

2274 
s>compute_antialias(s, g); 
2275 
#if defined(DEBUG)

2276 
sample_dump(1, g>sb_hybrid, 576); 
2277 
#endif

2278 
compute_imdct(s, g, &s>sb_samples[ch][18 * gr][0], s>mdct_buf[ch]); 
2279 
#if defined(DEBUG)

2280 
sample_dump(2, &s>sb_samples[ch][18 * gr][0], 576); 
2281 
#endif

2282 
} 
2283 
} /* gr */

2284 
if(get_bits_count(&s>gb)<0) 
2285 
skip_bits_long(&s>gb, get_bits_count(&s>gb)); 
2286 
return nb_granules * 18; 
2287 
} 
2288  
2289 
static int mp_decode_frame(MPADecodeContext *s, 
2290 
OUT_INT *samples, const uint8_t *buf, int buf_size) 
2291 
{ 
2292 
int i, nb_frames, ch;

2293 
OUT_INT *samples_ptr; 
2294  
2295 
init_get_bits(&s>gb, buf + HEADER_SIZE, (buf_size  HEADER_SIZE)*8);

2296  
2297 
/* skip error protection field */

2298 
if (s>error_protection)

2299 
skip_bits(&s>gb, 16);

2300  
2301 
dprintf(s>avctx, "frame %d:\n", s>frame_count);

2302 
switch(s>layer) {

2303 
case 1: 
2304 
s>avctx>frame_size = 384;

2305 
nb_frames = mp_decode_layer1(s); 
2306 
break;

2307 
case 2: 
2308 
s>avctx>frame_size = 1152;

2309 
nb_frames = mp_decode_layer2(s); 
2310 
break;

2311 
case 3: 
2312 
s>avctx>frame_size = s>lsf ? 576 : 1152; 
2313 
default:

2314 
nb_frames = mp_decode_layer3(s); 
2315  
2316 
s>last_buf_size=0;

2317 
if(s>in_gb.buffer){

2318 
align_get_bits(&s>gb); 
2319 
i= (s>gb.size_in_bits  get_bits_count(&s>gb))>>3;

2320 
if(i >= 0 && i <= BACKSTEP_SIZE){ 
2321 
memmove(s>last_buf, s>gb.buffer + (get_bits_count(&s>gb)>>3), i);

2322 
s>last_buf_size=i; 
2323 
}else

2324 
av_log(NULL, AV_LOG_ERROR, "invalid old backstep %d\n", i); 
2325 
s>gb= s>in_gb; 
2326 
s>in_gb.buffer= NULL;

2327 
} 
2328  
2329 
align_get_bits(&s>gb); 
2330 
assert((get_bits_count(&s>gb) & 7) == 0); 
2331 
i= (s>gb.size_in_bits  get_bits_count(&s>gb))>>3;

2332  
2333 
if(i<0  i > BACKSTEP_SIZE  nb_frames<0){ 
2334 
av_log(NULL, AV_LOG_ERROR, "invalid new backstep %d\n", i); 
2335 
i= FFMIN(BACKSTEP_SIZE, buf_size  HEADER_SIZE); 
2336 
} 
2337 
assert(i <= buf_size  HEADER_SIZE && i>= 0);

2338 
memcpy(s>last_buf + s>last_buf_size, s>gb.buffer + buf_size  HEADER_SIZE  i, i); 
2339 
s>last_buf_size += i; 
2340  
2341 
break;

2342 
} 
2343 
#if defined(DEBUG)

2344 
for(i=0;i<nb_frames;i++) { 
2345 
for(ch=0;ch<s>nb_channels;ch++) { 
2346 
int j;

2347 
dprintf(s>avctx, "%d%d:", i, ch);

2348 
for(j=0;j<SBLIMIT;j++) 
2349 
dprintf(s>avctx, " %0.6f", (double)s>sb_samples[ch][i][j] / FRAC_ONE); 
2350 
dprintf(s>avctx, "\n");

2351 
} 
2352 
} 
2353 
#endif

2354 
/* apply the synthesis filter */

2355 
for(ch=0;ch<s>nb_channels;ch++) { 
2356 
samples_ptr = samples + ch; 
2357 
for(i=0;i<nb_frames;i++) { 
2358 
ff_mpa_synth_filter(s>synth_buf[ch], &(s>synth_buf_offset[ch]), 
2359 
window, &s>dither_state, 
2360 
samples_ptr, s>nb_channels, 
2361 
s>sb_samples[ch][i]); 
2362 
samples_ptr += 32 * s>nb_channels;

2363 
} 
2364 
} 
2365 
#ifdef DEBUG

2366 
s>frame_count++; 
2367 
#endif

2368 
return nb_frames * 32 * sizeof(OUT_INT) * s>nb_channels; 
2369 
} 
2370  
2371 
static int decode_frame(AVCodecContext * avctx, 
2372 
void *data, int *data_size, 
2373 
const uint8_t * buf, int buf_size) 
2374 
{ 
2375 
MPADecodeContext *s = avctx>priv_data; 
2376 
uint32_t header; 
2377 
int out_size;

2378 
OUT_INT *out_samples = data; 
2379  
2380 
retry:

2381 
if(buf_size < HEADER_SIZE)

2382 
return 1; 
2383  
2384 
header = AV_RB32(buf); 
2385 
if(ff_mpa_check_header(header) < 0){ 
2386 
buf++; 
2387 
// buf_size;

2388 
av_log(avctx, AV_LOG_ERROR, "Header missing skipping one byte.\n");

2389 
goto retry;

2390 
} 
2391  
2392 
if (ff_mpegaudio_decode_header(s, header) == 1) { 
2393 
/* free format: prepare to compute frame size */

2394 
s>frame_size = 1;

2395 
return 1; 
2396 
} 
2397 
/* update codec info */

2398 
avctx>channels = s>nb_channels; 
2399 
avctx>bit_rate = s>bit_rate; 
2400 
avctx>sub_id = s>layer; 
2401  
2402 
if(s>frame_size<=0  s>frame_size > buf_size){ 
2403 
av_log(avctx, AV_LOG_ERROR, "incomplete frame\n");

2404 
return 1; 
2405 
}else if(s>frame_size < buf_size){ 
2406 
av_log(avctx, AV_LOG_ERROR, "incorrect frame size\n");

2407 
buf_size= s>frame_size; 
2408 
} 
2409  
2410 
out_size = mp_decode_frame(s, out_samples, buf, buf_size); 
2411 
if(out_size>=0){ 
2412 
*data_size = out_size; 
2413 
avctx>sample_rate = s>sample_rate; 
2414 
//FIXME maybe move the other codec info stuff from above here too

2415 
}else

2416 
av_log(avctx, AV_LOG_DEBUG, "Error while decoding MPEG audio frame.\n"); //FIXME return 1 / but also return the number of bytes consumed 
2417 
s>frame_size = 0;

2418 
return buf_size;

2419 
} 
2420  
2421 
static void flush(AVCodecContext *avctx){ 
2422 
MPADecodeContext *s = avctx>priv_data; 
2423 
memset(s>synth_buf, 0, sizeof(s>synth_buf)); 
2424 
s>last_buf_size= 0;

2425 
} 
2426  
2427 
#ifdef CONFIG_MP3ADU_DECODER

2428 
static int decode_frame_adu(AVCodecContext * avctx, 
2429 
void *data, int *data_size, 
2430 
const uint8_t * buf, int buf_size) 
2431 
{ 
2432 
MPADecodeContext *s = avctx>priv_data; 
2433 
uint32_t header; 
2434 
int len, out_size;

2435 
OUT_INT *out_samples = data; 
2436  
2437 
len = buf_size; 
2438  
2439 
// Discard too short frames

2440 
if (buf_size < HEADER_SIZE) {

2441 
*data_size = 0;

2442 
return buf_size;

2443 
} 
2444  
2445  
2446 
if (len > MPA_MAX_CODED_FRAME_SIZE)

2447 
len = MPA_MAX_CODED_FRAME_SIZE; 
2448  
2449 
// Get header and restore sync word

2450 
header = AV_RB32(buf)  0xffe00000;

2451  
2452 
if (ff_mpa_check_header(header) < 0) { // Bad header, discard frame 
2453 
*data_size = 0;

2454 
return buf_size;

2455 
} 
2456  
2457 
ff_mpegaudio_decode_header(s, header); 
2458 
/* update codec info */

2459 
avctx>sample_rate = s>sample_rate; 
2460 
avctx>channels = s>nb_channels; 
2461 
avctx>bit_rate = s>bit_rate; 
2462 
avctx>sub_id = s>layer; 
2463  
2464 
s>frame_size = len; 
2465  
2466 
if (avctx>parse_only) {

2467 
out_size = buf_size; 
2468 
} else {

2469 
out_size = mp_decode_frame(s, out_samples, buf, buf_size); 
2470 
} 
2471  
2472 
*data_size = out_size; 
2473 
return buf_size;

2474 
} 
2475 
#endif /* CONFIG_MP3ADU_DECODER */ 
2476  
2477 
#ifdef CONFIG_MP3ON4_DECODER

2478 
/* Next 3 arrays are indexed by channel config number (passed via codecdata) */

2479 
static int mp3Frames[16] = {0,1,1,2,3,3,4,5,2}; /* number of mp3 decoder instances */ 
2480 
static int mp3Channels[16] = {0,1,2,3,4,5,6,8,4}; /* total output channels */ 
2481 
/* offsets into output buffer, assume output order is FL FR BL BR C LFE */

2482 
static int chan_offset[9][5] = { 
2483 
{0},

2484 
{0}, // C 
2485 
{0}, // FLR 
2486 
{2,0}, // C FLR 
2487 
{2,0,3}, // C FLR BS 
2488 
{4,0,2}, // C FLR BLRS 
2489 
{4,0,2,5}, // C FLR BLRS LFE 
2490 
{4,0,2,6,5}, // C FLR BLRS BLR LFE 
2491 
{0,2} // FLR BLRS 
2492 
}; 
2493  
2494  
2495 
static int decode_init_mp3on4(AVCodecContext * avctx) 
2496 
{ 
2497 
MP3On4DecodeContext *s = avctx>priv_data; 
2498 
int i;

2499  
2500 
if ((avctx>extradata_size < 2)  (avctx>extradata == NULL)) { 
2501 
av_log(avctx, AV_LOG_ERROR, "Codec extradata missing or too short.\n");

2502 
return 1; 
2503 
} 
2504  
2505 
s>chan_cfg = (((unsigned char *)avctx>extradata)[1] >> 3) & 0x0f; 
2506 
s>frames = mp3Frames[s>chan_cfg]; 
2507 
if(!s>frames) {

2508 
av_log(avctx, AV_LOG_ERROR, "Invalid channel config number.\n");

2509 
return 1; 
2510 
} 
2511 
avctx>channels = mp3Channels[s>chan_cfg]; 
2512  
2513 
/* Init the first mp3 decoder in standard way, so that all tables get builded

2514 
* We replace avctx>priv_data with the context of the first decoder so that

2515 
* decode_init() does not have to be changed.

2516 
* Other decoders will be initialized here copying data from the first context

2517 
*/

2518 
// Allocate zeroed memory for the first decoder context

2519 
s>mp3decctx[0] = av_mallocz(sizeof(MPADecodeContext)); 
2520 
// Put decoder context in place to make init_decode() happy

2521 
avctx>priv_data = s>mp3decctx[0];

2522 
decode_init(avctx); 
2523 
// Restore mp3on4 context pointer

2524 
avctx>priv_data = s; 
2525 
s>mp3decctx[0]>adu_mode = 1; // Set adu mode 
2526  
2527 
/* Create a separate codec/context for each frame (first is already ok).

2528 
* Each frame is 1 or 2 channels  up to 5 frames allowed

2529 
*/

2530 
for (i = 1; i < s>frames; i++) { 
2531 
s>mp3decctx[i] = av_mallocz(sizeof(MPADecodeContext));

2532 
s>mp3decctx[i]>compute_antialias = s>mp3decctx[0]>compute_antialias;

2533 
s>mp3decctx[i]>adu_mode = 1;

2534 
s>mp3decctx[i]>avctx = avctx; 
2535 
} 
2536  
2537 
return 0; 
2538 
} 
2539  
2540  
2541 
static int decode_close_mp3on4(AVCodecContext * avctx) 
2542 
{ 
2543 
MP3On4DecodeContext *s = avctx>priv_data; 
2544 
int i;

2545  
2546 
for (i = 0; i < s>frames; i++) 
2547 
if (s>mp3decctx[i])

2548 
av_free(s>mp3decctx[i]); 
2549  
2550 
return 0; 
2551 
} 
2552  
2553  
2554 
static int decode_frame_mp3on4(AVCodecContext * avctx, 
2555 
void *data, int *data_size, 
2556 
const uint8_t * buf, int buf_size) 
2557 
{ 
2558 
MP3On4DecodeContext *s = avctx>priv_data; 
2559 
MPADecodeContext *m; 
2560 
int len, out_size = 0; 
2561 
uint32_t header; 
2562 
OUT_INT *out_samples = data; 
2563 
OUT_INT decoded_buf[MPA_FRAME_SIZE * MPA_MAX_CHANNELS]; 
2564 
OUT_INT *outptr, *bp; 
2565 
int fsize;

2566 
const unsigned char *start2 = buf, *start; 
2567 
int fr, i, j, n;

2568 
int off = avctx>channels;

2569 
int *coff = chan_offset[s>chan_cfg];

2570  
2571 
len = buf_size; 
2572  
2573 
// Discard too short frames

2574 
if (buf_size < HEADER_SIZE) {

2575 
*data_size = 0;

2576 
return buf_size;

2577 
} 
2578  
2579 
// If only one decoder interleave is not needed

2580 
outptr = s>frames == 1 ? out_samples : decoded_buf;

2581  
2582 
for (fr = 0; fr < s>frames; fr++) { 
2583 
start = start2; 
2584 
fsize = (start[0] << 4)  (start[1] >> 4); 
2585 
start2 += fsize; 
2586 
if (fsize > len)

2587 
fsize = len; 
2588 
len = fsize; 
2589 
if (fsize > MPA_MAX_CODED_FRAME_SIZE)

2590 
fsize = MPA_MAX_CODED_FRAME_SIZE; 
2591 
m = s>mp3decctx[fr]; 
2592 
assert (m != NULL);

2593  
2594 
// Get header

2595 
header = AV_RB32(start)  0xfff00000;

2596  
2597 
if (ff_mpa_check_header(header) < 0) { // Bad header, discard block 
2598 
*data_size = 0;

2599 
return buf_size;

2600 
} 
2601  
2602 
ff_mpegaudio_decode_header(m, header); 
2603 
mp_decode_frame(m, decoded_buf, start, fsize); 
2604  
2605 
n = MPA_FRAME_SIZE * m>nb_channels; 
2606 
out_size += n * sizeof(OUT_INT);

2607 
if(s>frames > 1) { 
2608 
/* interleave output data */

2609 
bp = out_samples + coff[fr]; 
2610 
if(m>nb_channels == 1) { 
2611 
for(j = 0; j < n; j++) { 
2612 
*bp = decoded_buf[j]; 
2613 
bp += off; 
2614 
} 
2615 
} else {

2616 
for(j = 0; j < n; j++) { 
2617 
bp[0] = decoded_buf[j++];

2618 
bp[1] = decoded_buf[j];

2619 
bp += off; 
2620 
} 
2621 
} 
2622 
} 
2623 
} 
2624  
2625 
/* update codec info */

2626 
avctx>sample_rate = s>mp3decctx[0]>sample_rate;

2627 
avctx>bit_rate = 0;

2628 
for (i = 0; i < s>frames; i++) 
2629 
avctx>bit_rate += s>mp3decctx[i]>bit_rate; 
2630  
2631 
*data_size = out_size; 
2632 
return buf_size;

2633 
} 
2634 
#endif /* CONFIG_MP3ON4_DECODER */ 
2635  
2636 
#ifdef CONFIG_MP2_DECODER

2637 
AVCodec mp2_decoder = 
2638 
{ 
2639 
"mp2",

2640 
CODEC_TYPE_AUDIO, 
2641 
CODEC_ID_MP2, 
2642 
sizeof(MPADecodeContext),

2643 
decode_init, 
2644 
NULL,

2645 
NULL,

2646 
decode_frame, 
2647 
CODEC_CAP_PARSE_ONLY, 
2648 
.flush= flush, 
2649 
}; 
2650 
#endif

2651 
#ifdef CONFIG_MP3_DECODER

2652 
AVCodec mp3_decoder = 
2653 
{ 
2654 
"mp3",

2655 
CODEC_TYPE_AUDIO, 
2656 
CODEC_ID_MP3, 
2657 
sizeof(MPADecodeContext),

2658 
decode_init, 
2659 
NULL,

2660 
NULL,

2661 
decode_frame, 
2662 
CODEC_CAP_PARSE_ONLY, 
2663 
.flush= flush, 
2664 
}; 
2665 
#endif

2666 
#ifdef CONFIG_MP3ADU_DECODER

2667 
AVCodec mp3adu_decoder = 
2668 
{ 
2669 
"mp3adu",

2670 
CODEC_TYPE_AUDIO, 
2671 
CODEC_ID_MP3ADU, 
2672 
sizeof(MPADecodeContext),

2673 
decode_init, 
2674 
NULL,

2675 
NULL,

2676 
decode_frame_adu, 
2677 
CODEC_CAP_PARSE_ONLY, 
2678 
.flush= flush, 
2679 
}; 
2680 
#endif

2681 
#ifdef CONFIG_MP3ON4_DECODER

2682 
AVCodec mp3on4_decoder = 
2683 
{ 
2684 
"mp3on4",

2685 
CODEC_TYPE_AUDIO, 
2686 
CODEC_ID_MP3ON4, 
2687 
sizeof(MP3On4DecodeContext),

2688 
decode_init_mp3on4, 
2689 
NULL,

2690 
decode_close_mp3on4, 
2691 
decode_frame_mp3on4, 
2692 
.flush= flush, 
2693 
}; 
2694 
#endif
