ffmpeg / libavcodec / mpegaudiodec.c @ 84dc2d8a
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/*


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* MPEG Audio decoder

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* Copyright (c) 2001, 2002 Fabrice Bellard

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*

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* This file is part of FFmpeg.

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*

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

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

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* License as published by the Free Software Foundation; either

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

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*

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

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

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

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* Lesser General Public License for more details.

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*

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

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

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

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*/

21  
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/**

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* @file libavcodec/mpegaudiodec.c

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* MPEG Audio decoder.

25 
*/

26  
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#include "avcodec.h" 
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#include "get_bits.h" 
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#include "dsputil.h" 
30  
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/*

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* TODO:

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

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*  test lsf / mpeg25 extensively.

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*/

36  
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#include "mpegaudio.h" 
38 
#include "mpegaudiodecheader.h" 
39  
40 
#include "mathops.h" 
41  
42 
/* WARNING: only correct for posititive numbers */

43 
#define FIXR(a) ((int)((a) * FRAC_ONE + 0.5)) 
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#define FRAC_RND(a) (((a) + (FRAC_ONE/2)) >> FRAC_BITS) 
45  
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#define FIXHR(a) ((int)((a) * (1LL<<32) + 0.5)) 
47  
48 
/****************/

49  
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#define HEADER_SIZE 4 
51  
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#include "mpegaudiodata.h" 
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#include "mpegaudiodectab.h" 
54  
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static void compute_antialias_integer(MPADecodeContext *s, GranuleDef *g); 
56 
static void compute_antialias_float(MPADecodeContext *s, GranuleDef *g); 
57  
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/* vlc structure for decoding layer 3 huffman tables */

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static VLC huff_vlc[16]; 
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static VLC_TYPE huff_vlc_tables[

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0+128+128+128+130+128+154+166+ 
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142+204+190+170+542+460+662+414 
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][2];

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static const int huff_vlc_tables_sizes[16] = { 
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0, 128, 128, 128, 130, 128, 154, 166, 
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142, 204, 190, 170, 542, 460, 662, 414 
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}; 
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static VLC huff_quad_vlc[2]; 
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static VLC_TYPE huff_quad_vlc_tables[128+16][2]; 
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static const int huff_quad_vlc_tables_sizes[2] = { 
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128, 16 
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}; 
73 
/* computed from band_size_long */

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static uint16_t band_index_long[9][23]; 
75 
#include "mpegaudio_tablegen.h" 
76 
/* intensity stereo coef table */

77 
static int32_t is_table[2][16]; 
78 
static int32_t is_table_lsf[2][2][16]; 
79 
static int32_t csa_table[8][4]; 
80 
static float csa_table_float[8][4]; 
81 
static int32_t mdct_win[8][36]; 
82  
83 
/* lower 2 bits: modulo 3, higher bits: shift */

84 
static uint16_t scale_factor_modshift[64]; 
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/* [i][j]: 2^(j/3) * FRAC_ONE * 2^(i+2) / (2^(i+2)  1) */

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static int32_t scale_factor_mult[15][3]; 
87 
/* mult table for layer 2 group quantization */

88  
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#define SCALE_GEN(v) \

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{ FIXR(1.0 * (v)), FIXR(0.7937005259 * (v)), FIXR(0.6299605249 * (v)) } 
91  
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static const int32_t scale_factor_mult2[3][3] = { 
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SCALE_GEN(4.0 / 3.0), /* 3 steps */ 
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SCALE_GEN(4.0 / 5.0), /* 5 steps */ 
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SCALE_GEN(4.0 / 9.0), /* 9 steps */ 
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}; 
97  
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DECLARE_ALIGNED(16, MPA_INT, ff_mpa_synth_window)[512]; 
99  
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/**

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* Convert region offsets to region sizes and truncate

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* size to big_values.

103 
*/

104 
void ff_region_offset2size(GranuleDef *g){

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int i, k, j=0; 
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g>region_size[2] = (576 / 2); 
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for(i=0;i<3;i++) { 
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k = FFMIN(g>region_size[i], g>big_values); 
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g>region_size[i] = k  j; 
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j = k; 
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} 
112 
} 
113  
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void ff_init_short_region(MPADecodeContext *s, GranuleDef *g){

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

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

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g>region_size[0] = (108 / 2); 
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} 
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g>region_size[1] = (576 / 2); 
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} 
127  
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void ff_init_long_region(MPADecodeContext *s, GranuleDef *g, int ra1, int ra2){ 
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int l;

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g>region_size[0] =

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

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

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

136 
} 
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void ff_compute_band_indexes(MPADecodeContext *s, GranuleDef *g){

139 
if (g>block_type == 2) { 
140 
if (g>switch_point) {

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

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

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

144 
if (s>sample_rate_index <= 2) 
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g>long_end = 8;

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

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else

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

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g>long_end = 0;

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g>short_start = 0;

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} 
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} else {

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g>short_start = 13;

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g>long_end = 22;

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} 
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} 
161  
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/* layer 1 unscaling */

163 
/* n = number of bits of the mantissa minus 1 */

164 
static inline int l1_unscale(int n, int mant, int scale_factor) 
165 
{ 
166 
int shift, mod;

167 
int64_t val; 
168  
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shift = scale_factor_modshift[scale_factor]; 
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mod = shift & 3;

171 
shift >>= 2;

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

175 
return (int)((val + (1LL << (shift  1))) >> shift); 
176 
} 
177  
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static inline int l2_unscale_group(int steps, int mant, int scale_factor) 
179 
{ 
180 
int shift, mod, val;

181  
182 
shift = scale_factor_modshift[scale_factor]; 
183 
mod = shift & 3;

184 
shift >>= 2;

185  
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val = (mant  (steps >> 1)) * scale_factor_mult2[steps >> 2][mod]; 
187 
/* NOTE: at this point, 0 <= shift <= 21 */

188 
if (shift > 0) 
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val = (val + (1 << (shift  1))) >> shift; 
190 
return val;

191 
} 
192  
193 
/* compute value^(4/3) * 2^(exponent/4). It normalized to FRAC_BITS */

194 
static inline int l3_unscale(int value, int exponent) 
195 
{ 
196 
unsigned int m; 
197 
int e;

198  
199 
e = table_4_3_exp [4*value + (exponent&3)]; 
200 
m = table_4_3_value[4*value + (exponent&3)]; 
201 
e = (exponent >> 2);

202 
assert(e>=1);

203 
if (e > 31) 
204 
return 0; 
205 
m = (m + (1 << (e1))) >> e; 
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return m;

208 
} 
209  
210 
/* all integer n^(4/3) computation code */

211 
#define DEV_ORDER 13 
212  
213 
#define POW_FRAC_BITS 24 
214 
#define POW_FRAC_ONE (1 << POW_FRAC_BITS) 
215 
#define POW_FIX(a) ((int)((a) * POW_FRAC_ONE)) 
216 
#define POW_MULL(a,b) (((int64_t)(a) * (int64_t)(b)) >> POW_FRAC_BITS)

217  
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static int dev_4_3_coefs[DEV_ORDER]; 
219  
220 
#if 0 /* unused */

221 
static int pow_mult3[3] = {

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POW_FIX(1.0),

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POW_FIX(1.25992104989487316476),

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POW_FIX(1.58740105196819947474),

225 
};

226 
#endif

227  
228 
static av_cold void int_pow_init(void) 
229 
{ 
230 
int i, a;

231  
232 
a = POW_FIX(1.0); 
233 
for(i=0;i<DEV_ORDER;i++) { 
234 
a = POW_MULL(a, POW_FIX(4.0 / 3.0)  i * POW_FIX(1.0)) / (i + 1); 
235 
dev_4_3_coefs[i] = a; 
236 
} 
237 
} 
238  
239 
#if 0 /* unused, remove? */

240 
/* return the mantissa and the binary exponent */

241 
static int int_pow(int i, int *exp_ptr)

242 
{

243 
int e, er, eq, j;

244 
int a, a1;

245 

246 
/* renormalize */

247 
a = i;

248 
e = POW_FRAC_BITS;

249 
while (a < (1 << (POW_FRAC_BITS  1))) {

250 
a = a << 1;

251 
e;

252 
}

253 
a = (1 << POW_FRAC_BITS);

254 
a1 = 0;

255 
for(j = DEV_ORDER  1; j >= 0; j)

256 
a1 = POW_MULL(a, dev_4_3_coefs[j] + a1);

257 
a = (1 << POW_FRAC_BITS) + a1;

258 
/* exponent compute (exact) */

259 
e = e * 4;

260 
er = e % 3;

261 
eq = e / 3;

262 
a = POW_MULL(a, pow_mult3[er]);

263 
while (a >= 2 * POW_FRAC_ONE) {

264 
a = a >> 1;

265 
eq++;

266 
}

267 
/* convert to float */

268 
while (a < POW_FRAC_ONE) {

269 
a = a << 1;

270 
eq;

271 
}

272 
/* now POW_FRAC_ONE <= a < 2 * POW_FRAC_ONE */

273 
#if POW_FRAC_BITS > FRAC_BITS

274 
a = (a + (1 << (POW_FRAC_BITS  FRAC_BITS  1))) >> (POW_FRAC_BITS  FRAC_BITS);

275 
/* correct overflow */

276 
if (a >= 2 * (1 << FRAC_BITS)) {

277 
a = a >> 1;

278 
eq++;

279 
}

280 
#endif

281 
*exp_ptr = eq; 
282 
return a;

283 
} 
284 
#endif

285  
286 
static av_cold int decode_init(AVCodecContext * avctx) 
287 
{ 
288 
MPADecodeContext *s = avctx>priv_data; 
289 
static int init=0; 
290 
int i, j, k;

291  
292 
s>avctx = avctx; 
293  
294 
avctx>sample_fmt= OUT_FMT; 
295 
s>error_recognition= avctx>error_recognition; 
296  
297 
if(avctx>antialias_algo != FF_AA_FLOAT)

298 
s>compute_antialias= compute_antialias_integer; 
299 
else

300 
s>compute_antialias= compute_antialias_float; 
301  
302 
if (!init && !avctx>parse_only) {

303 
int offset;

304  
305 
/* scale factors table for layer 1/2 */

306 
for(i=0;i<64;i++) { 
307 
int shift, mod;

308 
/* 1.0 (i = 3) is normalized to 2 ^ FRAC_BITS */

309 
shift = (i / 3);

310 
mod = i % 3;

311 
scale_factor_modshift[i] = mod  (shift << 2);

312 
} 
313  
314 
/* scale factor multiply for layer 1 */

315 
for(i=0;i<15;i++) { 
316 
int n, norm;

317 
n = i + 2;

318 
norm = ((INT64_C(1) << n) * FRAC_ONE) / ((1 << n)  1); 
319 
scale_factor_mult[i][0] = MULL(FIXR(1.0 * 2.0), norm, FRAC_BITS); 
320 
scale_factor_mult[i][1] = MULL(FIXR(0.7937005259 * 2.0), norm, FRAC_BITS); 
321 
scale_factor_mult[i][2] = MULL(FIXR(0.6299605249 * 2.0), norm, FRAC_BITS); 
322 
dprintf(avctx, "%d: norm=%x s=%x %x %x\n",

323 
i, norm, 
324 
scale_factor_mult[i][0],

325 
scale_factor_mult[i][1],

326 
scale_factor_mult[i][2]);

327 
} 
328  
329 
ff_mpa_synth_init(ff_mpa_synth_window); 
330  
331 
/* huffman decode tables */

332 
offset = 0;

333 
for(i=1;i<16;i++) { 
334 
const HuffTable *h = &mpa_huff_tables[i];

335 
int xsize, x, y;

336 
uint8_t tmp_bits [512];

337 
uint16_t tmp_codes[512];

338  
339 
memset(tmp_bits , 0, sizeof(tmp_bits )); 
340 
memset(tmp_codes, 0, sizeof(tmp_codes)); 
341  
342 
xsize = h>xsize; 
343  
344 
j = 0;

345 
for(x=0;x<xsize;x++) { 
346 
for(y=0;y<xsize;y++){ 
347 
tmp_bits [(x << 5)  y  ((x&&y)<<4)]= h>bits [j ]; 
348 
tmp_codes[(x << 5)  y  ((x&&y)<<4)]= h>codes[j++]; 
349 
} 
350 
} 
351  
352 
/* XXX: fail test */

353 
huff_vlc[i].table = huff_vlc_tables+offset; 
354 
huff_vlc[i].table_allocated = huff_vlc_tables_sizes[i]; 
355 
init_vlc(&huff_vlc[i], 7, 512, 
356 
tmp_bits, 1, 1, tmp_codes, 2, 2, 
357 
INIT_VLC_USE_NEW_STATIC); 
358 
offset += huff_vlc_tables_sizes[i]; 
359 
} 
360 
assert(offset == FF_ARRAY_ELEMS(huff_vlc_tables)); 
361  
362 
offset = 0;

363 
for(i=0;i<2;i++) { 
364 
huff_quad_vlc[i].table = huff_quad_vlc_tables+offset; 
365 
huff_quad_vlc[i].table_allocated = huff_quad_vlc_tables_sizes[i]; 
366 
init_vlc(&huff_quad_vlc[i], i == 0 ? 7 : 4, 16, 
367 
mpa_quad_bits[i], 1, 1, mpa_quad_codes[i], 1, 1, 
368 
INIT_VLC_USE_NEW_STATIC); 
369 
offset += huff_quad_vlc_tables_sizes[i]; 
370 
} 
371 
assert(offset == FF_ARRAY_ELEMS(huff_quad_vlc_tables)); 
372  
373 
for(i=0;i<9;i++) { 
374 
k = 0;

375 
for(j=0;j<22;j++) { 
376 
band_index_long[i][j] = k; 
377 
k += band_size_long[i][j]; 
378 
} 
379 
band_index_long[i][22] = k;

380 
} 
381  
382 
/* compute n ^ (4/3) and store it in mantissa/exp format */

383  
384 
int_pow_init(); 
385 
mpegaudio_tableinit(); 
386  
387 
for(i=0;i<7;i++) { 
388 
float f;

389 
int v;

390 
if (i != 6) { 
391 
f = tan((double)i * M_PI / 12.0); 
392 
v = FIXR(f / (1.0 + f)); 
393 
} else {

394 
v = FIXR(1.0); 
395 
} 
396 
is_table[0][i] = v;

397 
is_table[1][6  i] = v; 
398 
} 
399 
/* invalid values */

400 
for(i=7;i<16;i++) 
401 
is_table[0][i] = is_table[1][i] = 0.0; 
402  
403 
for(i=0;i<16;i++) { 
404 
double f;

405 
int e, k;

406  
407 
for(j=0;j<2;j++) { 
408 
e = (j + 1) * ((i + 1) >> 1); 
409 
f = pow(2.0, e / 4.0); 
410 
k = i & 1;

411 
is_table_lsf[j][k ^ 1][i] = FIXR(f);

412 
is_table_lsf[j][k][i] = FIXR(1.0); 
413 
dprintf(avctx, "is_table_lsf %d %d: %x %x\n",

414 
i, j, is_table_lsf[j][0][i], is_table_lsf[j][1][i]); 
415 
} 
416 
} 
417  
418 
for(i=0;i<8;i++) { 
419 
float ci, cs, ca;

420 
ci = ci_table[i]; 
421 
cs = 1.0 / sqrt(1.0 + ci * ci); 
422 
ca = cs * ci; 
423 
csa_table[i][0] = FIXHR(cs/4); 
424 
csa_table[i][1] = FIXHR(ca/4); 
425 
csa_table[i][2] = FIXHR(ca/4) + FIXHR(cs/4); 
426 
csa_table[i][3] = FIXHR(ca/4)  FIXHR(cs/4); 
427 
csa_table_float[i][0] = cs;

428 
csa_table_float[i][1] = ca;

429 
csa_table_float[i][2] = ca + cs;

430 
csa_table_float[i][3] = ca  cs;

431 
} 
432  
433 
/* compute mdct windows */

434 
for(i=0;i<36;i++) { 
435 
for(j=0; j<4; j++){ 
436 
double d;

437  
438 
if(j==2 && i%3 != 1) 
439 
continue;

440  
441 
d= sin(M_PI * (i + 0.5) / 36.0); 
442 
if(j==1){ 
443 
if (i>=30) d= 0; 
444 
else if(i>=24) d= sin(M_PI * (i  18 + 0.5) / 12.0); 
445 
else if(i>=18) d= 1; 
446 
}else if(j==3){ 
447 
if (i< 6) d= 0; 
448 
else if(i< 12) d= sin(M_PI * (i  6 + 0.5) / 12.0); 
449 
else if(i< 18) d= 1; 
450 
} 
451 
//merge last stage of imdct into the window coefficients

452 
d*= 0.5 / cos(M_PI*(2*i + 19)/72); 
453  
454 
if(j==2) 
455 
mdct_win[j][i/3] = FIXHR((d / (1<<5))); 
456 
else

457 
mdct_win[j][i ] = FIXHR((d / (1<<5))); 
458 
} 
459 
} 
460  
461 
/* NOTE: we do frequency inversion adter the MDCT by changing

462 
the sign of the right window coefs */

463 
for(j=0;j<4;j++) { 
464 
for(i=0;i<36;i+=2) { 
465 
mdct_win[j + 4][i] = mdct_win[j][i];

466 
mdct_win[j + 4][i + 1] = mdct_win[j][i + 1]; 
467 
} 
468 
} 
469  
470 
init = 1;

471 
} 
472  
473 
if (avctx>codec_id == CODEC_ID_MP3ADU)

474 
s>adu_mode = 1;

475 
return 0; 
476 
} 
477  
478 
/* tab[i][j] = 1.0 / (2.0 * cos(pi*(2*k+1) / 2^(6  j))) */

479  
480 
/* cos(i*pi/64) */

481  
482 
#define COS0_0 FIXHR(0.50060299823519630134/2) 
483 
#define COS0_1 FIXHR(0.50547095989754365998/2) 
484 
#define COS0_2 FIXHR(0.51544730992262454697/2) 
485 
#define COS0_3 FIXHR(0.53104259108978417447/2) 
486 
#define COS0_4 FIXHR(0.55310389603444452782/2) 
487 
#define COS0_5 FIXHR(0.58293496820613387367/2) 
488 
#define COS0_6 FIXHR(0.62250412303566481615/2) 
489 
#define COS0_7 FIXHR(0.67480834145500574602/2) 
490 
#define COS0_8 FIXHR(0.74453627100229844977/2) 
491 
#define COS0_9 FIXHR(0.83934964541552703873/2) 
492 
#define COS0_10 FIXHR(0.97256823786196069369/2) 
493 
#define COS0_11 FIXHR(1.16943993343288495515/4) 
494 
#define COS0_12 FIXHR(1.48416461631416627724/4) 
495 
#define COS0_13 FIXHR(2.05778100995341155085/8) 
496 
#define COS0_14 FIXHR(3.40760841846871878570/8) 
497 
#define COS0_15 FIXHR(10.19000812354805681150/32) 
498  
499 
#define COS1_0 FIXHR(0.50241928618815570551/2) 
500 
#define COS1_1 FIXHR(0.52249861493968888062/2) 
501 
#define COS1_2 FIXHR(0.56694403481635770368/2) 
502 
#define COS1_3 FIXHR(0.64682178335999012954/2) 
503 
#define COS1_4 FIXHR(0.78815462345125022473/2) 
504 
#define COS1_5 FIXHR(1.06067768599034747134/4) 
505 
#define COS1_6 FIXHR(1.72244709823833392782/4) 
506 
#define COS1_7 FIXHR(5.10114861868916385802/16) 
507  
508 
#define COS2_0 FIXHR(0.50979557910415916894/2) 
509 
#define COS2_1 FIXHR(0.60134488693504528054/2) 
510 
#define COS2_2 FIXHR(0.89997622313641570463/2) 
511 
#define COS2_3 FIXHR(2.56291544774150617881/8) 
512  
513 
#define COS3_0 FIXHR(0.54119610014619698439/2) 
514 
#define COS3_1 FIXHR(1.30656296487637652785/4) 
515  
516 
#define COS4_0 FIXHR(0.70710678118654752439/2) 
517  
518 
/* butterfly operator */

519 
#define BF(a, b, c, s)\

520 
{\ 
521 
tmp0 = tab[a] + tab[b];\ 
522 
tmp1 = tab[a]  tab[b];\ 
523 
tab[a] = tmp0;\ 
524 
tab[b] = MULH(tmp1<<(s), c);\ 
525 
} 
526  
527 
#define BF1(a, b, c, d)\

528 
{\ 
529 
BF(a, b, COS4_0, 1);\

530 
BF(c, d,COS4_0, 1);\

531 
tab[c] += tab[d];\ 
532 
} 
533  
534 
#define BF2(a, b, c, d)\

535 
{\ 
536 
BF(a, b, COS4_0, 1);\

537 
BF(c, d,COS4_0, 1);\

538 
tab[c] += tab[d];\ 
539 
tab[a] += tab[c];\ 
540 
tab[c] += tab[b];\ 
541 
tab[b] += tab[d];\ 
542 
} 
543  
544 
#define ADD(a, b) tab[a] += tab[b]

545  
546 
/* DCT32 without 1/sqrt(2) coef zero scaling. */

547 
static void dct32(int32_t *out, int32_t *tab) 
548 
{ 
549 
int tmp0, tmp1;

550  
551 
/* pass 1 */

552 
BF( 0, 31, COS0_0 , 1); 
553 
BF(15, 16, COS0_15, 5); 
554 
/* pass 2 */

555 
BF( 0, 15, COS1_0 , 1); 
556 
BF(16, 31,COS1_0 , 1); 
557 
/* pass 1 */

558 
BF( 7, 24, COS0_7 , 1); 
559 
BF( 8, 23, COS0_8 , 1); 
560 
/* pass 2 */

561 
BF( 7, 8, COS1_7 , 4); 
562 
BF(23, 24,COS1_7 , 4); 
563 
/* pass 3 */

564 
BF( 0, 7, COS2_0 , 1); 
565 
BF( 8, 15,COS2_0 , 1); 
566 
BF(16, 23, COS2_0 , 1); 
567 
BF(24, 31,COS2_0 , 1); 
568 
/* pass 1 */

569 
BF( 3, 28, COS0_3 , 1); 
570 
BF(12, 19, COS0_12, 2); 
571 
/* pass 2 */

572 
BF( 3, 12, COS1_3 , 1); 
573 
BF(19, 28,COS1_3 , 1); 
574 
/* pass 1 */

575 
BF( 4, 27, COS0_4 , 1); 
576 
BF(11, 20, COS0_11, 2); 
577 
/* pass 2 */

578 
BF( 4, 11, COS1_4 , 1); 
579 
BF(20, 27,COS1_4 , 1); 
580 
/* pass 3 */

581 
BF( 3, 4, COS2_3 , 3); 
582 
BF(11, 12,COS2_3 , 3); 
583 
BF(19, 20, COS2_3 , 3); 
584 
BF(27, 28,COS2_3 , 3); 
585 
/* pass 4 */

586 
BF( 0, 3, COS3_0 , 1); 
587 
BF( 4, 7,COS3_0 , 1); 
588 
BF( 8, 11, COS3_0 , 1); 
589 
BF(12, 15,COS3_0 , 1); 
590 
BF(16, 19, COS3_0 , 1); 
591 
BF(20, 23,COS3_0 , 1); 
592 
BF(24, 27, COS3_0 , 1); 
593 
BF(28, 31,COS3_0 , 1); 
594  
595  
596  
597 
/* pass 1 */

598 
BF( 1, 30, COS0_1 , 1); 
599 
BF(14, 17, COS0_14, 3); 
600 
/* pass 2 */

601 
BF( 1, 14, COS1_1 , 1); 
602 
BF(17, 30,COS1_1 , 1); 
603 
/* pass 1 */

604 
BF( 6, 25, COS0_6 , 1); 
605 
BF( 9, 22, COS0_9 , 1); 
606 
/* pass 2 */

607 
BF( 6, 9, COS1_6 , 2); 
608 
BF(22, 25,COS1_6 , 2); 
609 
/* pass 3 */

610 
BF( 1, 6, COS2_1 , 1); 
611 
BF( 9, 14,COS2_1 , 1); 
612 
BF(17, 22, COS2_1 , 1); 
613 
BF(25, 30,COS2_1 , 1); 
614  
615 
/* pass 1 */

616 
BF( 2, 29, COS0_2 , 1); 
617 
BF(13, 18, COS0_13, 3); 
618 
/* pass 2 */

619 
BF( 2, 13, COS1_2 , 1); 
620 
BF(18, 29,COS1_2 , 1); 
621 
/* pass 1 */

622 
BF( 5, 26, COS0_5 , 1); 
623 
BF(10, 21, COS0_10, 1); 
624 
/* pass 2 */

625 
BF( 5, 10, COS1_5 , 2); 
626 
BF(21, 26,COS1_5 , 2); 
627 
/* pass 3 */

628 
BF( 2, 5, COS2_2 , 1); 
629 
BF(10, 13,COS2_2 , 1); 
630 
BF(18, 21, COS2_2 , 1); 
631 
BF(26, 29,COS2_2 , 1); 
632 
/* pass 4 */

633 
BF( 1, 2, COS3_1 , 2); 
634 
BF( 5, 6,COS3_1 , 2); 
635 
BF( 9, 10, COS3_1 , 2); 
636 
BF(13, 14,COS3_1 , 2); 
637 
BF(17, 18, COS3_1 , 2); 
638 
BF(21, 22,COS3_1 , 2); 
639 
BF(25, 26, COS3_1 , 2); 
640 
BF(29, 30,COS3_1 , 2); 
641  
642 
/* pass 5 */

643 
BF1( 0, 1, 2, 3); 
644 
BF2( 4, 5, 6, 7); 
645 
BF1( 8, 9, 10, 11); 
646 
BF2(12, 13, 14, 15); 
647 
BF1(16, 17, 18, 19); 
648 
BF2(20, 21, 22, 23); 
649 
BF1(24, 25, 26, 27); 
650 
BF2(28, 29, 30, 31); 
651  
652 
/* pass 6 */

653  
654 
ADD( 8, 12); 
655 
ADD(12, 10); 
656 
ADD(10, 14); 
657 
ADD(14, 9); 
658 
ADD( 9, 13); 
659 
ADD(13, 11); 
660 
ADD(11, 15); 
661  
662 
out[ 0] = tab[0]; 
663 
out[16] = tab[1]; 
664 
out[ 8] = tab[2]; 
665 
out[24] = tab[3]; 
666 
out[ 4] = tab[4]; 
667 
out[20] = tab[5]; 
668 
out[12] = tab[6]; 
669 
out[28] = tab[7]; 
670 
out[ 2] = tab[8]; 
671 
out[18] = tab[9]; 
672 
out[10] = tab[10]; 
673 
out[26] = tab[11]; 
674 
out[ 6] = tab[12]; 
675 
out[22] = tab[13]; 
676 
out[14] = tab[14]; 
677 
out[30] = tab[15]; 
678  
679 
ADD(24, 28); 
680 
ADD(28, 26); 
681 
ADD(26, 30); 
682 
ADD(30, 25); 
683 
ADD(25, 29); 
684 
ADD(29, 27); 
685 
ADD(27, 31); 
686  
687 
out[ 1] = tab[16] + tab[24]; 
688 
out[17] = tab[17] + tab[25]; 
689 
out[ 9] = tab[18] + tab[26]; 
690 
out[25] = tab[19] + tab[27]; 
691 
out[ 5] = tab[20] + tab[28]; 
692 
out[21] = tab[21] + tab[29]; 
693 
out[13] = tab[22] + tab[30]; 
694 
out[29] = tab[23] + tab[31]; 
695 
out[ 3] = tab[24] + tab[20]; 
696 
out[19] = tab[25] + tab[21]; 
697 
out[11] = tab[26] + tab[22]; 
698 
out[27] = tab[27] + tab[23]; 
699 
out[ 7] = tab[28] + tab[18]; 
700 
out[23] = tab[29] + tab[19]; 
701 
out[15] = tab[30] + tab[17]; 
702 
out[31] = tab[31]; 
703 
} 
704  
705 
#if FRAC_BITS <= 15 
706  
707 
static inline int round_sample(int *sum) 
708 
{ 
709 
int sum1;

710 
sum1 = (*sum) >> OUT_SHIFT; 
711 
*sum &= (1<<OUT_SHIFT)1; 
712 
return av_clip(sum1, OUT_MIN, OUT_MAX);

713 
} 
714  
715 
/* signed 16x16 > 32 multiply add accumulate */

716 
#define MACS(rt, ra, rb) MAC16(rt, ra, rb)

717  
718 
/* signed 16x16 > 32 multiply */

719 
#define MULS(ra, rb) MUL16(ra, rb)

720  
721 
#define MLSS(rt, ra, rb) MLS16(rt, ra, rb)

722  
723 
#else

724  
725 
static inline int round_sample(int64_t *sum) 
726 
{ 
727 
int sum1;

728 
sum1 = (int)((*sum) >> OUT_SHIFT);

729 
*sum &= (1<<OUT_SHIFT)1; 
730 
return av_clip(sum1, OUT_MIN, OUT_MAX);

731 
} 
732  
733 
# define MULS(ra, rb) MUL64(ra, rb)

734 
# define MACS(rt, ra, rb) MAC64(rt, ra, rb)

735 
# define MLSS(rt, ra, rb) MLS64(rt, ra, rb)

736 
#endif

737  
738 
#define SUM8(op, sum, w, p) \

739 
{ \ 
740 
op(sum, (w)[0 * 64], (p)[0 * 64]); \ 
741 
op(sum, (w)[1 * 64], (p)[1 * 64]); \ 
742 
op(sum, (w)[2 * 64], (p)[2 * 64]); \ 
743 
op(sum, (w)[3 * 64], (p)[3 * 64]); \ 
744 
op(sum, (w)[4 * 64], (p)[4 * 64]); \ 
745 
op(sum, (w)[5 * 64], (p)[5 * 64]); \ 
746 
op(sum, (w)[6 * 64], (p)[6 * 64]); \ 
747 
op(sum, (w)[7 * 64], (p)[7 * 64]); \ 
748 
} 
749  
750 
#define SUM8P2(sum1, op1, sum2, op2, w1, w2, p) \

751 
{ \ 
752 
int tmp;\

753 
tmp = p[0 * 64];\ 
754 
op1(sum1, (w1)[0 * 64], tmp);\ 
755 
op2(sum2, (w2)[0 * 64], tmp);\ 
756 
tmp = p[1 * 64];\ 
757 
op1(sum1, (w1)[1 * 64], tmp);\ 
758 
op2(sum2, (w2)[1 * 64], tmp);\ 
759 
tmp = p[2 * 64];\ 
760 
op1(sum1, (w1)[2 * 64], tmp);\ 
761 
op2(sum2, (w2)[2 * 64], tmp);\ 
762 
tmp = p[3 * 64];\ 
763 
op1(sum1, (w1)[3 * 64], tmp);\ 
764 
op2(sum2, (w2)[3 * 64], tmp);\ 
765 
tmp = p[4 * 64];\ 
766 
op1(sum1, (w1)[4 * 64], tmp);\ 
767 
op2(sum2, (w2)[4 * 64], tmp);\ 
768 
tmp = p[5 * 64];\ 
769 
op1(sum1, (w1)[5 * 64], tmp);\ 
770 
op2(sum2, (w2)[5 * 64], tmp);\ 
771 
tmp = p[6 * 64];\ 
772 
op1(sum1, (w1)[6 * 64], tmp);\ 
773 
op2(sum2, (w2)[6 * 64], tmp);\ 
774 
tmp = p[7 * 64];\ 
775 
op1(sum1, (w1)[7 * 64], tmp);\ 
776 
op2(sum2, (w2)[7 * 64], tmp);\ 
777 
} 
778  
779 
void av_cold ff_mpa_synth_init(MPA_INT *window)

780 
{ 
781 
int i;

782  
783 
/* max = 18760, max sum over all 16 coefs : 44736 */

784 
for(i=0;i<257;i++) { 
785 
int v;

786 
v = ff_mpa_enwindow[i]; 
787 
#if WFRAC_BITS < 16 
788 
v = (v + (1 << (16  WFRAC_BITS  1))) >> (16  WFRAC_BITS); 
789 
#endif

790 
window[i] = v; 
791 
if ((i & 63) != 0) 
792 
v = v; 
793 
if (i != 0) 
794 
window[512  i] = v;

795 
} 
796 
} 
797  
798 
/* 32 sub band synthesis filter. Input: 32 sub band samples, Output:

799 
32 samples. */

800 
/* XXX: optimize by avoiding ring buffer usage */

801 
void ff_mpa_synth_filter(MPA_INT *synth_buf_ptr, int *synth_buf_offset, 
802 
MPA_INT *window, int *dither_state,

803 
OUT_INT *samples, int incr,

804 
int32_t sb_samples[SBLIMIT]) 
805 
{ 
806 
register MPA_INT *synth_buf;

807 
register const MPA_INT *w, *w2, *p; 
808 
int j, offset;

809 
OUT_INT *samples2; 
810 
#if FRAC_BITS <= 15 
811 
int32_t tmp[32];

812 
int sum, sum2;

813 
#else

814 
int64_t sum, sum2; 
815 
#endif

816  
817 
offset = *synth_buf_offset; 
818 
synth_buf = synth_buf_ptr + offset; 
819  
820 
#if FRAC_BITS <= 15 
821 
dct32(tmp, sb_samples); 
822 
for(j=0;j<32;j++) { 
823 
/* NOTE: can cause a loss in precision if very high amplitude

824 
sound */

825 
synth_buf[j] = av_clip_int16(tmp[j]); 
826 
} 
827 
#else

828 
dct32(synth_buf, sb_samples); 
829 
#endif

830  
831 
/* copy to avoid wrap */

832 
memcpy(synth_buf + 512, synth_buf, 32 * sizeof(MPA_INT)); 
833  
834 
samples2 = samples + 31 * incr;

835 
w = window; 
836 
w2 = window + 31;

837  
838 
sum = *dither_state; 
839 
p = synth_buf + 16;

840 
SUM8(MACS, sum, w, p); 
841 
p = synth_buf + 48;

842 
SUM8(MLSS, sum, w + 32, p);

843 
*samples = round_sample(&sum); 
844 
samples += incr; 
845 
w++; 
846  
847 
/* we calculate two samples at the same time to avoid one memory

848 
access per two sample */

849 
for(j=1;j<16;j++) { 
850 
sum2 = 0;

851 
p = synth_buf + 16 + j;

852 
SUM8P2(sum, MACS, sum2, MLSS, w, w2, p); 
853 
p = synth_buf + 48  j;

854 
SUM8P2(sum, MLSS, sum2, MLSS, w + 32, w2 + 32, p); 
855  
856 
*samples = round_sample(&sum); 
857 
samples += incr; 
858 
sum += sum2; 
859 
*samples2 = round_sample(&sum); 
860 
samples2 = incr; 
861 
w++; 
862 
w2; 
863 
} 
864  
865 
p = synth_buf + 32;

866 
SUM8(MLSS, sum, w + 32, p);

867 
*samples = round_sample(&sum); 
868 
*dither_state= sum; 
869  
870 
offset = (offset  32) & 511; 
871 
*synth_buf_offset = offset; 
872 
} 
873  
874 
#define C3 FIXHR(0.86602540378443864676/2) 
875  
876 
/* 0.5 / cos(pi*(2*i+1)/36) */

877 
static const int icos36[9] = { 
878 
FIXR(0.50190991877167369479), 
879 
FIXR(0.51763809020504152469), //0 
880 
FIXR(0.55168895948124587824), 
881 
FIXR(0.61038729438072803416), 
882 
FIXR(0.70710678118654752439), //1 
883 
FIXR(0.87172339781054900991), 
884 
FIXR(1.18310079157624925896), 
885 
FIXR(1.93185165257813657349), //2 
886 
FIXR(5.73685662283492756461), 
887 
}; 
888  
889 
/* 0.5 / cos(pi*(2*i+1)/36) */

890 
static const int icos36h[9] = { 
891 
FIXHR(0.50190991877167369479/2), 
892 
FIXHR(0.51763809020504152469/2), //0 
893 
FIXHR(0.55168895948124587824/2), 
894 
FIXHR(0.61038729438072803416/2), 
895 
FIXHR(0.70710678118654752439/2), //1 
896 
FIXHR(0.87172339781054900991/2), 
897 
FIXHR(1.18310079157624925896/4), 
898 
FIXHR(1.93185165257813657349/4), //2 
899 
// FIXHR(5.73685662283492756461),

900 
}; 
901  
902 
/* 12 points IMDCT. We compute it "by hand" by factorizing obvious

903 
cases. */

904 
static void imdct12(int *out, int *in) 
905 
{ 
906 
int in0, in1, in2, in3, in4, in5, t1, t2;

907  
908 
in0= in[0*3]; 
909 
in1= in[1*3] + in[0*3]; 
910 
in2= in[2*3] + in[1*3]; 
911 
in3= in[3*3] + in[2*3]; 
912 
in4= in[4*3] + in[3*3]; 
913 
in5= in[5*3] + in[4*3]; 
914 
in5 += in3; 
915 
in3 += in1; 
916  
917 
in2= MULH(2*in2, C3);

918 
in3= MULH(4*in3, C3);

919  
920 
t1 = in0  in4; 
921 
t2 = MULH(2*(in1  in5), icos36h[4]); 
922  
923 
out[ 7]=

924 
out[10]= t1 + t2;

925 
out[ 1]=

926 
out[ 4]= t1  t2;

927  
928 
in0 += in4>>1;

929 
in4 = in0 + in2; 
930 
in5 += 2*in1;

931 
in1 = MULH(in5 + in3, icos36h[1]);

932 
out[ 8]=

933 
out[ 9]= in4 + in1;

934 
out[ 2]=

935 
out[ 3]= in4  in1;

936  
937 
in0 = in2; 
938 
in5 = MULH(2*(in5  in3), icos36h[7]); 
939 
out[ 0]=

940 
out[ 5]= in0  in5;

941 
out[ 6]=

942 
out[11]= in0 + in5;

943 
} 
944  
945 
/* cos(pi*i/18) */

946 
#define C1 FIXHR(0.98480775301220805936/2) 
947 
#define C2 FIXHR(0.93969262078590838405/2) 
948 
#define C3 FIXHR(0.86602540378443864676/2) 
949 
#define C4 FIXHR(0.76604444311897803520/2) 
950 
#define C5 FIXHR(0.64278760968653932632/2) 
951 
#define C6 FIXHR(0.5/2) 
952 
#define C7 FIXHR(0.34202014332566873304/2) 
953 
#define C8 FIXHR(0.17364817766693034885/2) 
954  
955  
956 
/* using Lee like decomposition followed by hand coded 9 points DCT */

957 
static void imdct36(int *out, int *buf, int *in, int *win) 
958 
{ 
959 
int i, j, t0, t1, t2, t3, s0, s1, s2, s3;

960 
int tmp[18], *tmp1, *in1; 
961  
962 
for(i=17;i>=1;i) 
963 
in[i] += in[i1];

964 
for(i=17;i>=3;i=2) 
965 
in[i] += in[i2];

966  
967 
for(j=0;j<2;j++) { 
968 
tmp1 = tmp + j; 
969 
in1 = in + j; 
970 
#if 0

971 
//more accurate but slower

972 
int64_t t0, t1, t2, t3;

973 
t2 = in1[2*4] + in1[2*8]  in1[2*2];

974 

975 
t3 = (in1[2*0] + (int64_t)(in1[2*6]>>1))<<32;

976 
t1 = in1[2*0]  in1[2*6];

977 
tmp1[ 6] = t1  (t2>>1);

978 
tmp1[16] = t1 + t2;

979 

980 
t0 = MUL64(2*(in1[2*2] + in1[2*4]), C2);

981 
t1 = MUL64( in1[2*4]  in1[2*8] , 2*C8);

982 
t2 = MUL64(2*(in1[2*2] + in1[2*8]), C4);

983 

984 
tmp1[10] = (t3  t0  t2) >> 32;

985 
tmp1[ 2] = (t3 + t0 + t1) >> 32;

986 
tmp1[14] = (t3 + t2  t1) >> 32;

987 

988 
tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7]  in1[2*1]), C3);

989 
t2 = MUL64(2*(in1[2*1] + in1[2*5]), C1);

990 
t3 = MUL64( in1[2*5]  in1[2*7] , 2*C7);

991 
t0 = MUL64(2*in1[2*3], C3);

992 

993 
t1 = MUL64(2*(in1[2*1] + in1[2*7]), C5);

994 

995 
tmp1[ 0] = (t2 + t3 + t0) >> 32;

996 
tmp1[12] = (t2 + t1  t0) >> 32;

997 
tmp1[ 8] = (t3  t1  t0) >> 32;

998 
#else

999 
t2 = in1[2*4] + in1[2*8]  in1[2*2]; 
1000  
1001 
t3 = in1[2*0] + (in1[2*6]>>1); 
1002 
t1 = in1[2*0]  in1[2*6]; 
1003 
tmp1[ 6] = t1  (t2>>1); 
1004 
tmp1[16] = t1 + t2;

1005  
1006 
t0 = MULH(2*(in1[2*2] + in1[2*4]), C2); 
1007 
t1 = MULH( in1[2*4]  in1[2*8] , 2*C8); 
1008 
t2 = MULH(2*(in1[2*2] + in1[2*8]), C4); 
1009  
1010 
tmp1[10] = t3  t0  t2;

1011 
tmp1[ 2] = t3 + t0 + t1;

1012 
tmp1[14] = t3 + t2  t1;

1013  
1014 
tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7]  in1[2*1]), C3); 
1015 
t2 = MULH(2*(in1[2*1] + in1[2*5]), C1); 
1016 
t3 = MULH( in1[2*5]  in1[2*7] , 2*C7); 
1017 
t0 = MULH(2*in1[2*3], C3); 
1018  
1019 
t1 = MULH(2*(in1[2*1] + in1[2*7]), C5); 
1020  
1021 
tmp1[ 0] = t2 + t3 + t0;

1022 
tmp1[12] = t2 + t1  t0;

1023 
tmp1[ 8] = t3  t1  t0;

1024 
#endif

1025 
} 
1026  
1027 
i = 0;

1028 
for(j=0;j<4;j++) { 
1029 
t0 = tmp[i]; 
1030 
t1 = tmp[i + 2];

1031 
s0 = t1 + t0; 
1032 
s2 = t1  t0; 
1033  
1034 
t2 = tmp[i + 1];

1035 
t3 = tmp[i + 3];

1036 
s1 = MULH(2*(t3 + t2), icos36h[j]);

1037 
s3 = MULL(t3  t2, icos36[8  j], FRAC_BITS);

1038  
1039 
t0 = s0 + s1; 
1040 
t1 = s0  s1; 
1041 
out[(9 + j)*SBLIMIT] = MULH(t1, win[9 + j]) + buf[9 + j]; 
1042 
out[(8  j)*SBLIMIT] = MULH(t1, win[8  j]) + buf[8  j]; 
1043 
buf[9 + j] = MULH(t0, win[18 + 9 + j]); 
1044 
buf[8  j] = MULH(t0, win[18 + 8  j]); 
1045  
1046 
t0 = s2 + s3; 
1047 
t1 = s2  s3; 
1048 
out[(9 + 8  j)*SBLIMIT] = MULH(t1, win[9 + 8  j]) + buf[9 + 8  j]; 
1049 
out[( j)*SBLIMIT] = MULH(t1, win[ j]) + buf[ j]; 
1050 
buf[9 + 8  j] = MULH(t0, win[18 + 9 + 8  j]); 
1051 
buf[ + j] = MULH(t0, win[18 + j]);

1052 
i += 4;

1053 
} 
1054  
1055 
s0 = tmp[16];

1056 
s1 = MULH(2*tmp[17], icos36h[4]); 
1057 
t0 = s0 + s1; 
1058 
t1 = s0  s1; 
1059 
out[(9 + 4)*SBLIMIT] = MULH(t1, win[9 + 4]) + buf[9 + 4]; 
1060 
out[(8  4)*SBLIMIT] = MULH(t1, win[8  4]) + buf[8  4]; 
1061 
buf[9 + 4] = MULH(t0, win[18 + 9 + 4]); 
1062 
buf[8  4] = MULH(t0, win[18 + 8  4]); 
1063 
} 
1064  
1065 
/* return the number of decoded frames */

1066 
static int mp_decode_layer1(MPADecodeContext *s) 
1067 
{ 
1068 
int bound, i, v, n, ch, j, mant;

1069 
uint8_t allocation[MPA_MAX_CHANNELS][SBLIMIT]; 
1070 
uint8_t scale_factors[MPA_MAX_CHANNELS][SBLIMIT]; 
1071  
1072 
if (s>mode == MPA_JSTEREO)

1073 
bound = (s>mode_ext + 1) * 4; 
1074 
else

1075 
bound = SBLIMIT; 
1076  
1077 
/* allocation bits */

1078 
for(i=0;i<bound;i++) { 
1079 
for(ch=0;ch<s>nb_channels;ch++) { 
1080 
allocation[ch][i] = get_bits(&s>gb, 4);

1081 
} 
1082 
} 
1083 
for(i=bound;i<SBLIMIT;i++) {

1084 
allocation[0][i] = get_bits(&s>gb, 4); 
1085 
} 
1086  
1087 
/* scale factors */

1088 
for(i=0;i<bound;i++) { 
1089 
for(ch=0;ch<s>nb_channels;ch++) { 
1090 
if (allocation[ch][i])

1091 
scale_factors[ch][i] = get_bits(&s>gb, 6);

1092 
} 
1093 
} 
1094 
for(i=bound;i<SBLIMIT;i++) {

1095 
if (allocation[0][i]) { 
1096 
scale_factors[0][i] = get_bits(&s>gb, 6); 
1097 
scale_factors[1][i] = get_bits(&s>gb, 6); 
1098 
} 
1099 
} 
1100  
1101 
/* compute samples */

1102 
for(j=0;j<12;j++) { 
1103 
for(i=0;i<bound;i++) { 
1104 
for(ch=0;ch<s>nb_channels;ch++) { 
1105 
n = allocation[ch][i]; 
1106 
if (n) {

1107 
mant = get_bits(&s>gb, n + 1);

1108 
v = l1_unscale(n, mant, scale_factors[ch][i]); 
1109 
} else {

1110 
v = 0;

1111 
} 
1112 
s>sb_samples[ch][j][i] = v; 
1113 
} 
1114 
} 
1115 
for(i=bound;i<SBLIMIT;i++) {

1116 
n = allocation[0][i];

1117 
if (n) {

1118 
mant = get_bits(&s>gb, n + 1);

1119 
v = l1_unscale(n, mant, scale_factors[0][i]);

1120 
s>sb_samples[0][j][i] = v;

1121 
v = l1_unscale(n, mant, scale_factors[1][i]);

1122 
s>sb_samples[1][j][i] = v;

1123 
} else {

1124 
s>sb_samples[0][j][i] = 0; 
1125 
s>sb_samples[1][j][i] = 0; 
1126 
} 
1127 
} 
1128 
} 
1129 
return 12; 
1130 
} 
1131  
1132 
static int mp_decode_layer2(MPADecodeContext *s) 
1133 
{ 
1134 
int sblimit; /* number of used subbands */ 
1135 
const unsigned char *alloc_table; 
1136 
int table, bit_alloc_bits, i, j, ch, bound, v;

1137 
unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT]; 
1138 
unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT]; 
1139 
unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3], *sf; 
1140 
int scale, qindex, bits, steps, k, l, m, b;

1141  
1142 
/* select decoding table */

1143 
table = ff_mpa_l2_select_table(s>bit_rate / 1000, s>nb_channels,

1144 
s>sample_rate, s>lsf); 
1145 
sblimit = ff_mpa_sblimit_table[table]; 
1146 
alloc_table = ff_mpa_alloc_tables[table]; 
1147  
1148 
if (s>mode == MPA_JSTEREO)

1149 
bound = (s>mode_ext + 1) * 4; 
1150 
else

1151 
bound = sblimit; 
1152  
1153 
dprintf(s>avctx, "bound=%d sblimit=%d\n", bound, sblimit);

1154  
1155 
/* sanity check */

1156 
if( bound > sblimit ) bound = sblimit;

1157  
1158 
/* parse bit allocation */

1159 
j = 0;

1160 
for(i=0;i<bound;i++) { 
1161 
bit_alloc_bits = alloc_table[j]; 
1162 
for(ch=0;ch<s>nb_channels;ch++) { 
1163 
bit_alloc[ch][i] = get_bits(&s>gb, bit_alloc_bits); 
1164 
} 
1165 
j += 1 << bit_alloc_bits;

1166 
} 
1167 
for(i=bound;i<sblimit;i++) {

1168 
bit_alloc_bits = alloc_table[j]; 
1169 
v = get_bits(&s>gb, bit_alloc_bits); 
1170 
bit_alloc[0][i] = v;

1171 
bit_alloc[1][i] = v;

1172 
j += 1 << bit_alloc_bits;

1173 
} 
1174  
1175 
/* scale codes */

1176 
for(i=0;i<sblimit;i++) { 
1177 
for(ch=0;ch<s>nb_channels;ch++) { 
1178 
if (bit_alloc[ch][i])

1179 
scale_code[ch][i] = get_bits(&s>gb, 2);

1180 
} 
1181 
} 
1182  
1183 
/* scale factors */

1184 
for(i=0;i<sblimit;i++) { 
1185 
for(ch=0;ch<s>nb_channels;ch++) { 
1186 
if (bit_alloc[ch][i]) {

1187 
sf = scale_factors[ch][i]; 
1188 
switch(scale_code[ch][i]) {

1189 
default:

1190 
case 0: 
1191 
sf[0] = get_bits(&s>gb, 6); 
1192 
sf[1] = get_bits(&s>gb, 6); 
1193 
sf[2] = get_bits(&s>gb, 6); 
1194 
break;

1195 
case 2: 
1196 
sf[0] = get_bits(&s>gb, 6); 
1197 
sf[1] = sf[0]; 
1198 
sf[2] = sf[0]; 
1199 
break;

1200 
case 1: 
1201 
sf[0] = get_bits(&s>gb, 6); 
1202 
sf[2] = get_bits(&s>gb, 6); 
1203 
sf[1] = sf[0]; 
1204 
break;

1205 
case 3: 
1206 
sf[0] = get_bits(&s>gb, 6); 
1207 
sf[2] = get_bits(&s>gb, 6); 
1208 
sf[1] = sf[2]; 
1209 
break;

1210 
} 
1211 
} 
1212 
} 
1213 
} 
1214  
1215 
/* samples */

1216 
for(k=0;k<3;k++) { 
1217 
for(l=0;l<12;l+=3) { 
1218 
j = 0;

1219 
for(i=0;i<bound;i++) { 
1220 
bit_alloc_bits = alloc_table[j]; 
1221 
for(ch=0;ch<s>nb_channels;ch++) { 
1222 
b = bit_alloc[ch][i]; 
1223 
if (b) {

1224 
scale = scale_factors[ch][i][k]; 
1225 
qindex = alloc_table[j+b]; 
1226 
bits = ff_mpa_quant_bits[qindex]; 
1227 
if (bits < 0) { 
1228 
/* 3 values at the same time */

1229 
v = get_bits(&s>gb, bits); 
1230 
steps = ff_mpa_quant_steps[qindex]; 
1231 
s>sb_samples[ch][k * 12 + l + 0][i] = 
1232 
l2_unscale_group(steps, v % steps, scale); 
1233 
v = v / steps; 
1234 
s>sb_samples[ch][k * 12 + l + 1][i] = 
1235 
l2_unscale_group(steps, v % steps, scale); 
1236 
v = v / steps; 
1237 
s>sb_samples[ch][k * 12 + l + 2][i] = 
1238 
l2_unscale_group(steps, v, scale); 
1239 
} else {

1240 
for(m=0;m<3;m++) { 
1241 
v = get_bits(&s>gb, bits); 
1242 
v = l1_unscale(bits  1, v, scale);

1243 
s>sb_samples[ch][k * 12 + l + m][i] = v;

1244 
} 
1245 
} 
1246 
} else {

1247 
s>sb_samples[ch][k * 12 + l + 0][i] = 0; 
1248 
s>sb_samples[ch][k * 12 + l + 1][i] = 0; 
1249 
s>sb_samples[ch][k * 12 + l + 2][i] = 0; 
1250 
} 
1251 
} 
1252 
/* next subband in alloc table */

1253 
j += 1 << bit_alloc_bits;

1254 
} 
1255 
/* XXX: find a way to avoid this duplication of code */

1256 
for(i=bound;i<sblimit;i++) {

1257 
bit_alloc_bits = alloc_table[j]; 
1258 
b = bit_alloc[0][i];

1259 
if (b) {

1260 
int mant, scale0, scale1;

1261 
scale0 = scale_factors[0][i][k];

1262 
scale1 = scale_factors[1][i][k];

1263 
qindex = alloc_table[j+b]; 
1264 
bits = ff_mpa_quant_bits[qindex]; 
1265 
if (bits < 0) { 
1266 
/* 3 values at the same time */

1267 
v = get_bits(&s>gb, bits); 
1268 
steps = ff_mpa_quant_steps[qindex]; 
1269 
mant = v % steps; 
1270 
v = v / steps; 
1271 
s>sb_samples[0][k * 12 + l + 0][i] = 
1272 
l2_unscale_group(steps, mant, scale0); 
1273 
s>sb_samples[1][k * 12 + l + 0][i] = 
1274 
l2_unscale_group(steps, mant, scale1); 
1275 
mant = v % steps; 
1276 
v = v / steps; 
1277 
s>sb_samples[0][k * 12 + l + 1][i] = 
1278 
l2_unscale_group(steps, mant, scale0); 
1279 
s>sb_samples[1][k * 12 + l + 1][i] = 
1280 
l2_unscale_group(steps, mant, scale1); 
1281 
s>sb_samples[0][k * 12 + l + 2][i] = 
1282 
l2_unscale_group(steps, v, scale0); 
1283 
s>sb_samples[1][k * 12 + l + 2][i] = 
1284 
l2_unscale_group(steps, v, scale1); 
1285 
} else {

1286 
for(m=0;m<3;m++) { 
1287 
mant = get_bits(&s>gb, bits); 
1288 
s>sb_samples[0][k * 12 + l + m][i] = 
1289 
l1_unscale(bits  1, mant, scale0);

1290 
s>sb_samples[1][k * 12 + l + m][i] = 
1291 
l1_unscale(bits  1, mant, scale1);

1292 
} 
1293 
} 
1294 
} else {

1295 
s>sb_samples[0][k * 12 + l + 0][i] = 0; 
1296 
s>sb_samples[0][k * 12 + l + 1][i] = 0; 
1297 
s>sb_samples[0][k * 12 + l + 2][i] = 0; 
1298 
s>sb_samples[1][k * 12 + l + 0][i] = 0; 
1299 
s>sb_samples[1][k * 12 + l + 1][i] = 0; 
1300 
s>sb_samples[1][k * 12 + l + 2][i] = 0; 
1301 
} 
1302 
/* next subband in alloc table */

1303 
j += 1 << bit_alloc_bits;

1304 
} 
1305 
/* fill remaining samples to zero */

1306 
for(i=sblimit;i<SBLIMIT;i++) {

1307 
for(ch=0;ch<s>nb_channels;ch++) { 
1308 
s>sb_samples[ch][k * 12 + l + 0][i] = 0; 
1309 
s>sb_samples[ch][k * 12 + l + 1][i] = 0; 
1310 
s>sb_samples[ch][k * 12 + l + 2][i] = 0; 
1311 
} 
1312 
} 
1313 
} 
1314 
} 
1315 
return 3 * 12; 
1316 
} 
1317  
1318 
static inline void lsf_sf_expand(int *slen, 
1319 
int sf, int n1, int n2, int n3) 
1320 
{ 
1321 
if (n3) {

1322 
slen[3] = sf % n3;

1323 
sf /= n3; 
1324 
} else {

1325 
slen[3] = 0; 
1326 
} 
1327 
if (n2) {

1328 
slen[2] = sf % n2;

1329 
sf /= n2; 
1330 
} else {

1331 
slen[2] = 0; 
1332 
} 
1333 
slen[1] = sf % n1;

1334 
sf /= n1; 
1335 
slen[0] = sf;

1336 
} 
1337  
1338 
static void exponents_from_scale_factors(MPADecodeContext *s, 
1339 
GranuleDef *g, 
1340 
int16_t *exponents) 
1341 
{ 
1342 
const uint8_t *bstab, *pretab;

1343 
int len, i, j, k, l, v0, shift, gain, gains[3]; 
1344 
int16_t *exp_ptr; 
1345  
1346 
exp_ptr = exponents; 
1347 
gain = g>global_gain  210;

1348 
shift = g>scalefac_scale + 1;

1349  
1350 
bstab = band_size_long[s>sample_rate_index]; 
1351 
pretab = mpa_pretab[g>preflag]; 
1352 
for(i=0;i<g>long_end;i++) { 
1353 
v0 = gain  ((g>scale_factors[i] + pretab[i]) << shift) + 400;

1354 
len = bstab[i]; 
1355 
for(j=len;j>0;j) 
1356 
*exp_ptr++ = v0; 
1357 
} 
1358  
1359 
if (g>short_start < 13) { 
1360 
bstab = band_size_short[s>sample_rate_index]; 
1361 
gains[0] = gain  (g>subblock_gain[0] << 3); 
1362 
gains[1] = gain  (g>subblock_gain[1] << 3); 
1363 
gains[2] = gain  (g>subblock_gain[2] << 3); 
1364 
k = g>long_end; 
1365 
for(i=g>short_start;i<13;i++) { 
1366 
len = bstab[i]; 
1367 
for(l=0;l<3;l++) { 
1368 
v0 = gains[l]  (g>scale_factors[k++] << shift) + 400;

1369 
for(j=len;j>0;j) 
1370 
*exp_ptr++ = v0; 
1371 
} 
1372 
} 
1373 
} 
1374 
} 
1375  
1376 
/* handle n = 0 too */

1377 
static inline int get_bitsz(GetBitContext *s, int n) 
1378 
{ 
1379 
if (n == 0) 
1380 
return 0; 
1381 
else

1382 
return get_bits(s, n);

1383 
} 
1384  
1385  
1386 
static void switch_buffer(MPADecodeContext *s, int *pos, int *end_pos, int *end_pos2){ 
1387 
if(s>in_gb.buffer && *pos >= s>gb.size_in_bits){

1388 
s>gb= s>in_gb; 
1389 
s>in_gb.buffer=NULL;

1390 
assert((get_bits_count(&s>gb) & 7) == 0); 
1391 
skip_bits_long(&s>gb, *pos  *end_pos); 
1392 
*end_pos2= 
1393 
*end_pos= *end_pos2 + get_bits_count(&s>gb)  *pos; 
1394 
*pos= get_bits_count(&s>gb); 
1395 
} 
1396 
} 
1397  
1398 
static int huffman_decode(MPADecodeContext *s, GranuleDef *g, 
1399 
int16_t *exponents, int end_pos2)

1400 
{ 
1401 
int s_index;

1402 
int i;

1403 
int last_pos, bits_left;

1404 
VLC *vlc; 
1405 
int end_pos= FFMIN(end_pos2, s>gb.size_in_bits);

1406  
1407 
/* low frequencies (called big values) */

1408 
s_index = 0;

1409 
for(i=0;i<3;i++) { 
1410 
int j, k, l, linbits;

1411 
j = g>region_size[i]; 
1412 
if (j == 0) 
1413 
continue;

1414 
/* select vlc table */

1415 
k = g>table_select[i]; 
1416 
l = mpa_huff_data[k][0];

1417 
linbits = mpa_huff_data[k][1];

1418 
vlc = &huff_vlc[l]; 
1419  
1420 
if(!l){

1421 
memset(&g>sb_hybrid[s_index], 0, sizeof(*g>sb_hybrid)*2*j); 
1422 
s_index += 2*j;

1423 
continue;

1424 
} 
1425  
1426 
/* read huffcode and compute each couple */

1427 
for(;j>0;j) { 
1428 
int exponent, x, y, v;

1429 
int pos= get_bits_count(&s>gb);

1430  
1431 
if (pos >= end_pos){

1432 
// av_log(NULL, AV_LOG_ERROR, "pos: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);

1433 
switch_buffer(s, &pos, &end_pos, &end_pos2); 
1434 
// av_log(NULL, AV_LOG_ERROR, "new pos: %d %d\n", pos, end_pos);

1435 
if(pos >= end_pos)

1436 
break;

1437 
} 
1438 
y = get_vlc2(&s>gb, vlc>table, 7, 3); 
1439  
1440 
if(!y){

1441 
g>sb_hybrid[s_index ] = 
1442 
g>sb_hybrid[s_index+1] = 0; 
1443 
s_index += 2;

1444 
continue;

1445 
} 
1446  
1447 
exponent= exponents[s_index]; 
1448  
1449 
dprintf(s>avctx, "region=%d n=%d x=%d y=%d exp=%d\n",

1450 
i, g>region_size[i]  j, x, y, exponent); 
1451 
if(y&16){ 
1452 
x = y >> 5;

1453 
y = y & 0x0f;

1454 
if (x < 15){ 
1455 
v = expval_table[ exponent ][ x ]; 
1456 
// v = expval_table[ (exponent&3) ][ x ] >> FFMIN(0  (exponent>>2), 31);

1457 
}else{

1458 
x += get_bitsz(&s>gb, linbits); 
1459 
v = l3_unscale(x, exponent); 
1460 
} 
1461 
if (get_bits1(&s>gb))

1462 
v = v; 
1463 
g>sb_hybrid[s_index] = v; 
1464 
if (y < 15){ 
1465 
v = expval_table[ exponent ][ y ]; 
1466 
}else{

1467 
y += get_bitsz(&s>gb, linbits); 
1468 
v = l3_unscale(y, exponent); 
1469 
} 
1470 
if (get_bits1(&s>gb))

1471 
v = v; 
1472 
g>sb_hybrid[s_index+1] = v;

1473 
}else{

1474 
x = y >> 5;

1475 
y = y & 0x0f;

1476 
x += y; 
1477 
if (x < 15){ 
1478 
v = expval_table[ exponent ][ x ]; 
1479 
}else{

1480 
x += get_bitsz(&s>gb, linbits); 
1481 
v = l3_unscale(x, exponent); 
1482 
} 
1483 
if (get_bits1(&s>gb))

1484 
v = v; 
1485 
g>sb_hybrid[s_index+!!y] = v; 
1486 
g>sb_hybrid[s_index+ !y] = 0;

1487 
} 
1488 
s_index+=2;

1489 
} 
1490 
} 
1491  
1492 
/* high frequencies */

1493 
vlc = &huff_quad_vlc[g>count1table_select]; 
1494 
last_pos=0;

1495 
while (s_index <= 572) { 
1496 
int pos, code;

1497 
pos = get_bits_count(&s>gb); 
1498 
if (pos >= end_pos) {

1499 
if (pos > end_pos2 && last_pos){

1500 
/* some encoders generate an incorrect size for this

1501 
part. We must go back into the data */

1502 
s_index = 4;

1503 
skip_bits_long(&s>gb, last_pos  pos); 
1504 
av_log(s>avctx, AV_LOG_INFO, "overread, skip %d enddists: %d %d\n", last_pos  pos, end_pospos, end_pos2pos);

1505 
if(s>error_recognition >= FF_ER_COMPLIANT)

1506 
s_index=0;

1507 
break;

1508 
} 
1509 
// av_log(NULL, AV_LOG_ERROR, "pos2: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);

1510 
switch_buffer(s, &pos, &end_pos, &end_pos2); 
1511 
// av_log(NULL, AV_LOG_ERROR, "new pos2: %d %d %d\n", pos, end_pos, s_index);

1512 
if(pos >= end_pos)

1513 
break;

1514 
} 
1515 
last_pos= pos; 
1516  
1517 
code = get_vlc2(&s>gb, vlc>table, vlc>bits, 1);

1518 
dprintf(s>avctx, "t=%d code=%d\n", g>count1table_select, code);

1519 
g>sb_hybrid[s_index+0]=

1520 
g>sb_hybrid[s_index+1]=

1521 
g>sb_hybrid[s_index+2]=

1522 
g>sb_hybrid[s_index+3]= 0; 
1523 
while(code){

1524 
static const int idxtab[16]={3,3,2,2,1,1,1,1,0,0,0,0,0,0,0,0}; 
1525 
int v;

1526 
int pos= s_index+idxtab[code];

1527 
code ^= 8>>idxtab[code];

1528 
v = exp_table[ exponents[pos] ]; 
1529 
// v = exp_table[ (exponents[pos]&3) ] >> FFMIN(0  (exponents[pos]>>2), 31);

1530 
if(get_bits1(&s>gb))

1531 
v = v; 
1532 
g>sb_hybrid[pos] = v; 
1533 
} 
1534 
s_index+=4;

1535 
} 
1536 
/* skip extension bits */

1537 
bits_left = end_pos2  get_bits_count(&s>gb); 
1538 
//av_log(NULL, AV_LOG_ERROR, "left:%d buf:%p\n", bits_left, s>in_gb.buffer);

1539 
if (bits_left < 0 && s>error_recognition >= FF_ER_COMPLIANT) { 
1540 
av_log(s>avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);

1541 
s_index=0;

1542 
}else if(bits_left > 0 && s>error_recognition >= FF_ER_AGGRESSIVE){ 
1543 
av_log(s>avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);

1544 
s_index=0;

1545 
} 
1546 
memset(&g>sb_hybrid[s_index], 0, sizeof(*g>sb_hybrid)*(576  s_index)); 
1547 
skip_bits_long(&s>gb, bits_left); 
1548  
1549 
i= get_bits_count(&s>gb); 
1550 
switch_buffer(s, &i, &end_pos, &end_pos2); 
1551  
1552 
return 0; 
1553 
} 
1554  
1555 
/* Reorder short blocks from bitstream order to interleaved order. It

1556 
would be faster to do it in parsing, but the code would be far more

1557 
complicated */

1558 
static void reorder_block(MPADecodeContext *s, GranuleDef *g) 
1559 
{ 
1560 
int i, j, len;

1561 
int32_t *ptr, *dst, *ptr1; 
1562 
int32_t tmp[576];

1563  
1564 
if (g>block_type != 2) 
1565 
return;

1566  
1567 
if (g>switch_point) {

1568 
if (s>sample_rate_index != 8) { 
1569 
ptr = g>sb_hybrid + 36;

1570 
} else {

1571 
ptr = g>sb_hybrid + 48;

1572 
} 
1573 
} else {

1574 
ptr = g>sb_hybrid; 
1575 
} 
1576  
1577 
for(i=g>short_start;i<13;i++) { 
1578 
len = band_size_short[s>sample_rate_index][i]; 
1579 
ptr1 = ptr; 
1580 
dst = tmp; 
1581 
for(j=len;j>0;j) { 
1582 
*dst++ = ptr[0*len];

1583 
*dst++ = ptr[1*len];

1584 
*dst++ = ptr[2*len];

1585 
ptr++; 
1586 
} 
1587 
ptr+=2*len;

1588 
memcpy(ptr1, tmp, len * 3 * sizeof(*ptr1)); 
1589 
} 
1590 
} 
1591  
1592 
#define ISQRT2 FIXR(0.70710678118654752440) 
1593  
1594 
static void compute_stereo(MPADecodeContext *s, 
1595 
GranuleDef *g0, GranuleDef *g1) 
1596 
{ 
1597 
int i, j, k, l;

1598 
int32_t v1, v2; 
1599 
int sf_max, tmp0, tmp1, sf, len, non_zero_found;

1600 
int32_t (*is_tab)[16];

1601 
int32_t *tab0, *tab1; 
1602 
int non_zero_found_short[3]; 
1603  
1604 
/* intensity stereo */

1605 
if (s>mode_ext & MODE_EXT_I_STEREO) {

1606 
if (!s>lsf) {

1607 
is_tab = is_table; 
1608 
sf_max = 7;

1609 
} else {

1610 
is_tab = is_table_lsf[g1>scalefac_compress & 1];

1611 
sf_max = 16;

1612 
} 
1613  
1614 
tab0 = g0>sb_hybrid + 576;

1615 
tab1 = g1>sb_hybrid + 576;

1616  
1617 
non_zero_found_short[0] = 0; 
1618 
non_zero_found_short[1] = 0; 
1619 
non_zero_found_short[2] = 0; 
1620 
k = (13  g1>short_start) * 3 + g1>long_end  3; 
1621 
for(i = 12;i >= g1>short_start;i) { 
1622 
/* for last band, use previous scale factor */

1623 
if (i != 11) 
1624 
k = 3;

1625 
len = band_size_short[s>sample_rate_index][i]; 
1626 
for(l=2;l>=0;l) { 
1627 
tab0 = len; 
1628 
tab1 = len; 
1629 
if (!non_zero_found_short[l]) {

1630 
/* test if non zero band. if so, stop doing istereo */

1631 
for(j=0;j<len;j++) { 
1632 
if (tab1[j] != 0) { 
1633 
non_zero_found_short[l] = 1;

1634 
goto found1;

1635 
} 
1636 
} 
1637 
sf = g1>scale_factors[k + l]; 
1638 
if (sf >= sf_max)

1639 
goto found1;

1640  
1641 
v1 = is_tab[0][sf];

1642 
v2 = is_tab[1][sf];

1643 
for(j=0;j<len;j++) { 
1644 
tmp0 = tab0[j]; 
1645 
tab0[j] = MULL(tmp0, v1, FRAC_BITS); 
1646 
tab1[j] = MULL(tmp0, v2, FRAC_BITS); 
1647 
} 
1648 
} else {

1649 
found1:

1650 
if (s>mode_ext & MODE_EXT_MS_STEREO) {

1651 
/* lower part of the spectrum : do ms stereo

1652 
if enabled */

1653 
for(j=0;j<len;j++) { 
1654 
tmp0 = tab0[j]; 
1655 
tmp1 = tab1[j]; 
1656 
tab0[j] = MULL(tmp0 + tmp1, ISQRT2, FRAC_BITS); 
1657 
tab1[j] = MULL(tmp0  tmp1, ISQRT2, FRAC_BITS); 
1658 
} 
1659 
} 
1660 
} 
1661 
} 
1662 
} 
1663  
1664 
non_zero_found = non_zero_found_short[0] 

1665 
non_zero_found_short[1] 

1666 
non_zero_found_short[2];

1667  
1668 
for(i = g1>long_end  1;i >= 0;i) { 
1669 
len = band_size_long[s>sample_rate_index][i]; 
1670 
tab0 = len; 
1671 
tab1 = len; 
1672 
/* test if non zero band. if so, stop doing istereo */

1673 
if (!non_zero_found) {

1674 
for(j=0;j<len;j++) { 
1675 
if (tab1[j] != 0) { 
1676 
non_zero_found = 1;

1677 
goto found2;

1678 
} 
1679 
} 
1680 
/* for last band, use previous scale factor */

1681 
k = (i == 21) ? 20 : i; 
1682 
sf = g1>scale_factors[k]; 
1683 
if (sf >= sf_max)

1684 
goto found2;

1685 
v1 = is_tab[0][sf];

1686 
v2 = is_tab[1][sf];

1687 
for(j=0;j<len;j++) { 
1688 
tmp0 = tab0[j]; 
1689 
tab0[j] = MULL(tmp0, v1, FRAC_BITS); 
1690 
tab1[j] = MULL(tmp0, v2, FRAC_BITS); 
1691 
} 
1692 
} else {

1693 
found2:

1694 
if (s>mode_ext & MODE_EXT_MS_STEREO) {

1695 
/* lower part of the spectrum : do ms stereo

1696 
if enabled */

1697 
for(j=0;j<len;j++) { 
1698 
tmp0 = tab0[j]; 
1699 
tmp1 = tab1[j]; 
1700 
tab0[j] = MULL(tmp0 + tmp1, ISQRT2, FRAC_BITS); 
1701 
tab1[j] = MULL(tmp0  tmp1, ISQRT2, FRAC_BITS); 
1702 
} 
1703 
} 
1704 
} 
1705 
} 
1706 
} else if (s>mode_ext & MODE_EXT_MS_STEREO) { 
1707 
/* ms stereo ONLY */

1708 
/* NOTE: the 1/sqrt(2) normalization factor is included in the

1709 
global gain */

1710 
tab0 = g0>sb_hybrid; 
1711 
tab1 = g1>sb_hybrid; 
1712 
for(i=0;i<576;i++) { 
1713 
tmp0 = tab0[i]; 
1714 
tmp1 = tab1[i]; 
1715 
tab0[i] = tmp0 + tmp1; 
1716 
tab1[i] = tmp0  tmp1; 
1717 
} 
1718 
} 
1719 
} 
1720  
1721 
static void compute_antialias_integer(MPADecodeContext *s, 
1722 
GranuleDef *g) 
1723 
{ 
1724 
int32_t *ptr, *csa; 
1725 
int n, i;

1726  
1727 
/* we antialias only "long" bands */

1728 
if (g>block_type == 2) { 
1729 
if (!g>switch_point)

1730 
return;

1731 
/* XXX: check this for 8000Hz case */

1732 
n = 1;

1733 
} else {

1734 
n = SBLIMIT  1;

1735 
} 
1736  
1737 
ptr = g>sb_hybrid + 18;

1738 
for(i = n;i > 0;i) { 
1739 
int tmp0, tmp1, tmp2;

1740 
csa = &csa_table[0][0]; 
1741 
#define INT_AA(j) \

1742 
tmp0 = ptr[1j];\

1743 
tmp1 = ptr[ j];\ 
1744 
tmp2= MULH(tmp0 + tmp1, csa[0+4*j]);\ 
1745 
ptr[1j] = 4*(tmp2  MULH(tmp1, csa[2+4*j]));\ 
1746 
ptr[ j] = 4*(tmp2 + MULH(tmp0, csa[3+4*j])); 
1747  
1748 
INT_AA(0)

1749 
INT_AA(1)

1750 
INT_AA(2)

1751 
INT_AA(3)

1752 
INT_AA(4)

1753 
INT_AA(5)

1754 
INT_AA(6)

1755 
INT_AA(7)

1756  
1757 
ptr += 18;

1758 
} 
1759 
} 
1760  
1761 
static void compute_antialias_float(MPADecodeContext *s, 
1762 
GranuleDef *g) 
1763 
{ 
1764 
int32_t *ptr; 
1765 
int n, i;

1766  
1767 
/* we antialias only "long" bands */

1768 
if (g>block_type == 2) { 
1769 
if (!g>switch_point)

1770 
return;

1771 
/* XXX: check this for 8000Hz case */

1772 
n = 1;

1773 
} else {

1774 
n = SBLIMIT  1;

1775 
} 
1776  
1777 
ptr = g>sb_hybrid + 18;

1778 
for(i = n;i > 0;i) { 
1779 
float tmp0, tmp1;

1780 
float *csa = &csa_table_float[0][0]; 
1781 
#define FLOAT_AA(j)\

1782 
tmp0= ptr[1j];\

1783 
tmp1= ptr[ j];\ 
1784 
ptr[1j] = lrintf(tmp0 * csa[0+4*j]  tmp1 * csa[1+4*j]);\ 
1785 
ptr[ j] = lrintf(tmp0 * csa[1+4*j] + tmp1 * csa[0+4*j]); 
1786  
1787 
FLOAT_AA(0)

1788 
FLOAT_AA(1)

1789 
FLOAT_AA(2)

1790 
FLOAT_AA(3)

1791 
FLOAT_AA(4)

1792 
FLOAT_AA(5)

1793 
FLOAT_AA(6)

1794 
FLOAT_AA(7)

1795  
1796 
ptr += 18;

1797 
} 
1798 
} 
1799  
1800 
static void compute_imdct(MPADecodeContext *s, 
1801 
GranuleDef *g, 
1802 
int32_t *sb_samples, 
1803 
int32_t *mdct_buf) 
1804 
{ 
1805 
int32_t *ptr, *win, *win1, *buf, *out_ptr, *ptr1; 
1806 
int32_t out2[12];

1807 
int i, j, mdct_long_end, v, sblimit;

1808  
1809 
/* find last non zero block */

1810 
ptr = g>sb_hybrid + 576;

1811 
ptr1 = g>sb_hybrid + 2 * 18; 
1812 
while (ptr >= ptr1) {

1813 
ptr = 6;

1814 
v = ptr[0]  ptr[1]  ptr[2]  ptr[3]  ptr[4]  ptr[5]; 
1815 
if (v != 0) 
1816 
break;

1817 
} 
1818 
sblimit = ((ptr  g>sb_hybrid) / 18) + 1; 
1819  
1820 
if (g>block_type == 2) { 
1821 
/* XXX: check for 8000 Hz */

1822 
if (g>switch_point)

1823 
mdct_long_end = 2;

1824 
else

1825 
mdct_long_end = 0;

1826 
} else {

1827 
mdct_long_end = sblimit; 
1828 
} 
1829  
1830 
buf = mdct_buf; 
1831 
ptr = g>sb_hybrid; 
1832 
for(j=0;j<mdct_long_end;j++) { 
1833 
/* apply window & overlap with previous buffer */

1834 
out_ptr = sb_samples + j; 
1835 
/* select window */

1836 
if (g>switch_point && j < 2) 
1837 
win1 = mdct_win[0];

1838 
else

1839 
win1 = mdct_win[g>block_type]; 
1840 
/* select frequency inversion */

1841 
win = win1 + ((4 * 36) & (j & 1)); 
1842 
imdct36(out_ptr, buf, ptr, win); 
1843 
out_ptr += 18*SBLIMIT;

1844 
ptr += 18;

1845 
buf += 18;

1846 
} 
1847 
for(j=mdct_long_end;j<sblimit;j++) {

1848 
/* select frequency inversion */

1849 
win = mdct_win[2] + ((4 * 36) & (j & 1)); 
1850 
out_ptr = sb_samples + j; 
1851  
1852 
for(i=0; i<6; i++){ 
1853 
*out_ptr = buf[i]; 
1854 
out_ptr += SBLIMIT; 
1855 
} 
1856 
imdct12(out2, ptr + 0);

1857 
for(i=0;i<6;i++) { 
1858 
*out_ptr = MULH(out2[i], win[i]) + buf[i + 6*1]; 
1859 
buf[i + 6*2] = MULH(out2[i + 6], win[i + 6]); 
1860 
out_ptr += SBLIMIT; 
1861 
} 
1862 
imdct12(out2, ptr + 1);

1863 
for(i=0;i<6;i++) { 
1864 
*out_ptr = MULH(out2[i], win[i]) + buf[i + 6*2]; 
1865 
buf[i + 6*0] = MULH(out2[i + 6], win[i + 6]); 
1866 
out_ptr += SBLIMIT; 
1867 
} 
1868 
imdct12(out2, ptr + 2);

1869 
for(i=0;i<6;i++) { 
1870 
buf[i + 6*0] = MULH(out2[i], win[i]) + buf[i + 6*0]; 
1871 
buf[i + 6*1] = MULH(out2[i + 6], win[i + 6]); 
1872 
buf[i + 6*2] = 0; 
1873 
} 
1874 
ptr += 18;

1875 
buf += 18;

1876 
} 
1877 
/* zero bands */

1878 
for(j=sblimit;j<SBLIMIT;j++) {

1879 
/* overlap */

1880 
out_ptr = sb_samples + j; 
1881 
for(i=0;i<18;i++) { 
1882 
*out_ptr = buf[i]; 
1883 
buf[i] = 0;

1884 
out_ptr += SBLIMIT; 
1885 
} 
1886 
buf += 18;

1887 
} 
1888 
} 
1889  
1890 
/* main layer3 decoding function */

1891 
static int mp_decode_layer3(MPADecodeContext *s) 
1892 
{ 
1893 
int nb_granules, main_data_begin, private_bits;

1894 
int gr, ch, blocksplit_flag, i, j, k, n, bits_pos;

1895 
GranuleDef *g; 
1896 
int16_t exponents[576];

1897  
1898 
/* read side info */

1899 
if (s>lsf) {

1900 
main_data_begin = get_bits(&s>gb, 8);

1901 
private_bits = get_bits(&s>gb, s>nb_channels); 
1902 
nb_granules = 1;

1903 
} else {

1904 
main_data_begin = get_bits(&s>gb, 9);

1905 
if (s>nb_channels == 2) 
1906 
private_bits = get_bits(&s>gb, 3);

1907 
else

1908 
private_bits = get_bits(&s>gb, 5);

1909 
nb_granules = 2;

1910 
for(ch=0;ch<s>nb_channels;ch++) { 
1911 
s>granules[ch][0].scfsi = 0;/* all scale factors are transmitted */ 
1912 
s>granules[ch][1].scfsi = get_bits(&s>gb, 4); 
1913 
} 
1914 
} 
1915  
1916 
for(gr=0;gr<nb_granules;gr++) { 
1917 
for(ch=0;ch<s>nb_channels;ch++) { 
1918 
dprintf(s>avctx, "gr=%d ch=%d: side_info\n", gr, ch);

1919 
g = &s>granules[ch][gr]; 
1920 
g>part2_3_length = get_bits(&s>gb, 12);

1921 
g>big_values = get_bits(&s>gb, 9);

1922 
if(g>big_values > 288){ 
1923 
av_log(s>avctx, AV_LOG_ERROR, "big_values too big\n");

1924 
return 1; 
1925 
} 
1926  
1927 
g>global_gain = get_bits(&s>gb, 8);

1928 
/* if MS stereo only is selected, we precompute the

1929 
1/sqrt(2) renormalization factor */

1930 
if ((s>mode_ext & (MODE_EXT_MS_STEREO  MODE_EXT_I_STEREO)) ==

1931 
MODE_EXT_MS_STEREO) 
1932 
g>global_gain = 2;

1933 
if (s>lsf)

1934 
g>scalefac_compress = get_bits(&s>gb, 9);

1935 
else

1936 
g>scalefac_compress = get_bits(&s>gb, 4);

1937 
blocksplit_flag = get_bits1(&s>gb); 
1938 
if (blocksplit_flag) {

1939 
g>block_type = get_bits(&s>gb, 2);

1940 
if (g>block_type == 0){ 
1941 
av_log(s>avctx, AV_LOG_ERROR, "invalid block type\n");

1942 
return 1; 
1943 
} 
1944 
g>switch_point = get_bits1(&s>gb); 
1945 
for(i=0;i<2;i++) 
1946 
g>table_select[i] = get_bits(&s>gb, 5);

1947 
for(i=0;i<3;i++) 
1948 
g>subblock_gain[i] = get_bits(&s>gb, 3);

1949 
ff_init_short_region(s, g); 
1950 
} else {

1951 
int region_address1, region_address2;

1952 
g>block_type = 0;

1953 
g>switch_point = 0;

1954 
for(i=0;i<3;i++) 
1955 
g>table_select[i] = get_bits(&s>gb, 5);

1956 
/* compute huffman coded region sizes */

1957 
region_address1 = get_bits(&s>gb, 4);

1958 
region_address2 = get_bits(&s>gb, 3);

1959 
dprintf(s>avctx, "region1=%d region2=%d\n",

1960 
region_address1, region_address2); 
1961 
ff_init_long_region(s, g, region_address1, region_address2); 
1962 
} 
1963 
ff_region_offset2size(g); 
1964 
ff_compute_band_indexes(s, g); 
1965  
1966 
g>preflag = 0;

1967 
if (!s>lsf)

1968 
g>preflag = get_bits1(&s>gb); 
1969 
g>scalefac_scale = get_bits1(&s>gb); 
1970 
g>count1table_select = get_bits1(&s>gb); 
1971 
dprintf(s>avctx, "block_type=%d switch_point=%d\n",

1972 
g>block_type, g>switch_point); 
1973 
} 
1974 
} 
1975  
1976 
if (!s>adu_mode) {

1977 
const uint8_t *ptr = s>gb.buffer + (get_bits_count(&s>gb)>>3); 
1978 
assert((get_bits_count(&s>gb) & 7) == 0); 
1979 
/* now we get bits from the main_data_begin offset */

1980 
dprintf(s>avctx, "seekback: %d\n", main_data_begin);

1981 
//av_log(NULL, AV_LOG_ERROR, "backstep:%d, lastbuf:%d\n", main_data_begin, s>last_buf_size);

1982  
1983 
memcpy(s>last_buf + s>last_buf_size, ptr, EXTRABYTES); 
1984 
s>in_gb= s>gb; 
1985 
init_get_bits(&s>gb, s>last_buf, s>last_buf_size*8);

1986 
skip_bits_long(&s>gb, 8*(s>last_buf_size  main_data_begin));

1987 
} 
1988  
1989 
for(gr=0;gr<nb_granules;gr++) { 
1990 
for(ch=0;ch<s>nb_channels;ch++) { 
1991 
g = &s>granules[ch][gr]; 
1992 
if(get_bits_count(&s>gb)<0){ 
1993 
av_log(s>avctx, AV_LOG_DEBUG, "mdb:%d, lastbuf:%d skipping granule %d\n",

1994 
main_data_begin, s>last_buf_size, gr); 
1995 
skip_bits_long(&s>gb, g>part2_3_length); 
1996 
memset(g>sb_hybrid, 0, sizeof(g>sb_hybrid)); 
1997 
if(get_bits_count(&s>gb) >= s>gb.size_in_bits && s>in_gb.buffer){

1998 
skip_bits_long(&s>in_gb, get_bits_count(&s>gb)  s>gb.size_in_bits); 
1999 
s>gb= s>in_gb; 
2000 
s>in_gb.buffer=NULL;

2001 
} 
2002 
continue;

2003 
} 
2004  
2005 
bits_pos = get_bits_count(&s>gb); 
2006  
2007 
if (!s>lsf) {

2008 
uint8_t *sc; 
2009 
int slen, slen1, slen2;

2010  
2011 
/* MPEG1 scale factors */

2012 
slen1 = slen_table[0][g>scalefac_compress];

2013 
slen2 = slen_table[1][g>scalefac_compress];

2014 
dprintf(s>avctx, "slen1=%d slen2=%d\n", slen1, slen2);

2015 
if (g>block_type == 2) { 
2016 
n = g>switch_point ? 17 : 18; 
2017 
j = 0;

2018 
if(slen1){

2019 
for(i=0;i<n;i++) 
2020 
g>scale_factors[j++] = get_bits(&s>gb, slen1); 
2021 
}else{

2022 
for(i=0;i<n;i++) 
2023 
g>scale_factors[j++] = 0;

2024 
} 
2025 
if(slen2){

2026 
for(i=0;i<18;i++) 
2027 
g>scale_factors[j++] = get_bits(&s>gb, slen2); 
2028 
for(i=0;i<3;i++) 
2029 
g>scale_factors[j++] = 0;

2030 
}else{

2031 
for(i=0;i<21;i++) 
2032 
g>scale_factors[j++] = 0;

2033 
} 
2034 
} else {

2035 
sc = s>granules[ch][0].scale_factors;

2036 
j = 0;

2037 
for(k=0;k<4;k++) { 
2038 
n = (k == 0 ? 6 : 5); 
2039 
if ((g>scfsi & (0x8 >> k)) == 0) { 
2040 
slen = (k < 2) ? slen1 : slen2;

2041 
if(slen){

2042 
for(i=0;i<n;i++) 
2043 
g>scale_factors[j++] = get_bits(&s>gb, slen); 
2044 
}else{

2045 
for(i=0;i<n;i++) 
2046 
g>scale_factors[j++] = 0;

2047 
} 
2048 
} else {

2049 
/* simply copy from last granule */

2050 
for(i=0;i<n;i++) { 
2051 
g>scale_factors[j] = sc[j]; 
2052 
j++; 
2053 
} 
2054 
} 
2055 
} 
2056 
g>scale_factors[j++] = 0;

2057 
} 
2058 
} else {

2059 
int tindex, tindex2, slen[4], sl, sf; 
2060  
2061 
/* LSF scale factors */

2062 
if (g>block_type == 2) { 
2063 
tindex = g>switch_point ? 2 : 1; 
2064 
} else {

2065 
tindex = 0;

2066 
} 
2067 
sf = g>scalefac_compress; 
2068 
if ((s>mode_ext & MODE_EXT_I_STEREO) && ch == 1) { 
2069 
/* intensity stereo case */

2070 
sf >>= 1;

2071 
if (sf < 180) { 
2072 
lsf_sf_expand(slen, sf, 6, 6, 0); 
2073 
tindex2 = 3;

2074 
} else if (sf < 244) { 
2075 
lsf_sf_expand(slen, sf  180, 4, 4, 0); 
2076 
tindex2 = 4;

2077 
} else {

2078 
lsf_sf_expand(slen, sf  244, 3, 0, 0); 
2079 
tindex2 = 5;

2080 
} 
2081 
} else {

2082 
/* normal case */

2083 
if (sf < 400) { 
2084 
lsf_sf_expand(slen, sf, 5, 4, 4); 
2085 
tindex2 = 0;

2086 
} else if (sf < 500) { 
2087 
lsf_sf_expand(slen, sf  400, 5, 4, 0); 
2088 
tindex2 = 1;

2089 
} else {

2090 
lsf_sf_expand(slen, sf  500, 3, 0, 0); 
2091 
tindex2 = 2;

2092 
g>preflag = 1;

2093 
} 
2094 
} 
2095  
2096 
j = 0;

2097 
for(k=0;k<4;k++) { 
2098 
n = lsf_nsf_table[tindex2][tindex][k]; 
2099 
sl = slen[k]; 
2100 
if(sl){

2101 
for(i=0;i<n;i++) 
2102 
g>scale_factors[j++] = get_bits(&s>gb, sl); 
2103 
}else{

2104 
for(i=0;i<n;i++) 
2105 
g>scale_factors[j++] = 0;

2106 
} 
2107 
} 
2108 
/* XXX: should compute exact size */

2109 
for(;j<40;j++) 
2110 
g>scale_factors[j] = 0;

2111 
} 
2112  
2113 
exponents_from_scale_factors(s, g, exponents); 
2114  
2115 
/* read Huffman coded residue */

2116 
huffman_decode(s, g, exponents, bits_pos + g>part2_3_length); 
2117 
} /* ch */

2118  
2119 
if (s>nb_channels == 2) 
2120 
compute_stereo(s, &s>granules[0][gr], &s>granules[1][gr]); 
2121  
2122 
for(ch=0;ch<s>nb_channels;ch++) { 
2123 
g = &s>granules[ch][gr]; 
2124  
2125 
reorder_block(s, g); 
2126 
s>compute_antialias(s, g); 
2127 
compute_imdct(s, g, &s>sb_samples[ch][18 * gr][0], s>mdct_buf[ch]); 
2128 
} 
2129 
} /* gr */

2130 
if(get_bits_count(&s>gb)<0) 
2131 
skip_bits_long(&s>gb, get_bits_count(&s>gb)); 
2132 
return nb_granules * 18; 
2133 
} 
2134  
2135 
static int mp_decode_frame(MPADecodeContext *s, 
2136 
OUT_INT *samples, const uint8_t *buf, int buf_size) 
2137 
{ 
2138 
int i, nb_frames, ch;

2139 
OUT_INT *samples_ptr; 
2140  
2141 
init_get_bits(&s>gb, buf + HEADER_SIZE, (buf_size  HEADER_SIZE)*8);

2142  
2143 
/* skip error protection field */

2144 
if (s>error_protection)

2145 
skip_bits(&s>gb, 16);

2146  
2147 
dprintf(s>avctx, "frame %d:\n", s>frame_count);

2148 
switch(s>layer) {

2149 
case 1: 
2150 
s>avctx>frame_size = 384;

2151 
nb_frames = mp_decode_layer1(s); 
2152 
break;

2153 
case 2: 
2154 
s>avctx>frame_size = 1152;

2155 
nb_frames = mp_decode_layer2(s); 
2156 
break;

2157 
case 3: 
2158 
s>avctx>frame_size = s>lsf ? 576 : 1152; 
2159 
default:

2160 
nb_frames = mp_decode_layer3(s); 
2161  
2162 
s>last_buf_size=0;

2163 
if(s>in_gb.buffer){

2164 
align_get_bits(&s>gb); 
2165 
i= get_bits_left(&s>gb)>>3;

2166 
if(i >= 0 && i <= BACKSTEP_SIZE){ 
2167 
memmove(s>last_buf, s>gb.buffer + (get_bits_count(&s>gb)>>3), i);

2168 
s>last_buf_size=i; 
2169 
}else

2170 
av_log(s>avctx, AV_LOG_ERROR, "invalid old backstep %d\n", i);

2171 
s>gb= s>in_gb; 
2172 
s>in_gb.buffer= NULL;

2173 
} 
2174  
2175 
align_get_bits(&s>gb); 
2176 
assert((get_bits_count(&s>gb) & 7) == 0); 
2177 
i= get_bits_left(&s>gb)>>3;

2178  
2179 
if(i<0  i > BACKSTEP_SIZE  nb_frames<0){ 
2180 
if(i<0) 
2181 
av_log(s>avctx, AV_LOG_ERROR, "invalid new backstep %d\n", i);

2182 
i= FFMIN(BACKSTEP_SIZE, buf_size  HEADER_SIZE); 
2183 
} 
2184 
assert(i <= buf_size  HEADER_SIZE && i>= 0);

2185 
memcpy(s>last_buf + s>last_buf_size, s>gb.buffer + buf_size  HEADER_SIZE  i, i); 
2186 
s>last_buf_size += i; 
2187  
2188 
break;

2189 
} 
2190  
2191 
/* apply the synthesis filter */

2192 
for(ch=0;ch<s>nb_channels;ch++) { 
2193 
samples_ptr = samples + ch; 
2194 
for(i=0;i<nb_frames;i++) { 
2195 
ff_mpa_synth_filter(s>synth_buf[ch], &(s>synth_buf_offset[ch]), 
2196 
ff_mpa_synth_window, &s>dither_state, 
2197 
samples_ptr, s>nb_channels, 
2198 
s>sb_samples[ch][i]); 
2199 
samples_ptr += 32 * s>nb_channels;

2200 
} 
2201 
} 
2202  
2203 
return nb_frames * 32 * sizeof(OUT_INT) * s>nb_channels; 
2204 
} 
2205  
2206 
static int decode_frame(AVCodecContext * avctx, 
2207 
void *data, int *data_size, 
2208 
AVPacket *avpkt) 
2209 
{ 
2210 
const uint8_t *buf = avpkt>data;

2211 
int buf_size = avpkt>size;

2212 
MPADecodeContext *s = avctx>priv_data; 
2213 
uint32_t header; 
2214 
int out_size;

2215 
OUT_INT *out_samples = data; 
2216  
2217 
if(buf_size < HEADER_SIZE)

2218 
return 1; 
2219  
2220 
header = AV_RB32(buf); 
2221 
if(ff_mpa_check_header(header) < 0){ 
2222 
av_log(avctx, AV_LOG_ERROR, "Header missing\n");

2223 
return 1; 
2224 
} 
2225  
2226 
if (ff_mpegaudio_decode_header((MPADecodeHeader *)s, header) == 1) { 
2227 
/* free format: prepare to compute frame size */

2228 
s>frame_size = 1;

2229 
return 1; 
2230 
} 
2231 
/* update codec info */

2232 
avctx>channels = s>nb_channels; 
2233 
avctx>bit_rate = s>bit_rate; 
2234 
avctx>sub_id = s>layer; 
2235  
2236 
if(*data_size < 1152*avctx>channels*sizeof(OUT_INT)) 
2237 
return 1; 
2238 
*data_size = 0;

2239  
2240 
if(s>frame_size<=0  s>frame_size > buf_size){ 
2241 
av_log(avctx, AV_LOG_ERROR, "incomplete frame\n");

2242 
return 1; 
2243 
}else if(s>frame_size < buf_size){ 
2244 
av_log(avctx, AV_LOG_ERROR, "incorrect frame size\n");

2245 
buf_size= s>frame_size; 
2246 
} 
2247  
2248 
out_size = mp_decode_frame(s, out_samples, buf, buf_size); 
2249 
if(out_size>=0){ 
2250 
*data_size = out_size; 
2251 
avctx>sample_rate = s>sample_rate; 
2252 
//FIXME maybe move the other codec info stuff from above here too

2253 
}else

2254 
av_log(avctx, AV_LOG_DEBUG, "Error while decoding MPEG audio frame.\n"); //FIXME return 1 / but also return the number of bytes consumed 
2255 
s>frame_size = 0;

2256 
return buf_size;

2257 
} 
2258  
2259 
static void flush(AVCodecContext *avctx){ 
2260 
MPADecodeContext *s = avctx>priv_data; 
2261 
memset(s>synth_buf, 0, sizeof(s>synth_buf)); 
2262 
s>last_buf_size= 0;

2263 
} 
2264  
2265 
#if CONFIG_MP3ADU_DECODER

2266 
static int decode_frame_adu(AVCodecContext * avctx, 
2267 
void *data, int *data_size, 
2268 
AVPacket *avpkt) 
2269 
{ 
2270 
const uint8_t *buf = avpkt>data;

2271 
int buf_size = avpkt>size;

2272 
MPADecodeContext *s = avctx>priv_data; 
2273 
uint32_t header; 
2274 
int len, out_size;

2275 
OUT_INT *out_samples = data; 
2276  
2277 
len = buf_size; 
2278  
2279 
// Discard too short frames

2280 
if (buf_size < HEADER_SIZE) {

2281 
*data_size = 0;

2282 
return buf_size;

2283 
} 
2284  
2285  
2286 
if (len > MPA_MAX_CODED_FRAME_SIZE)

2287 
len = MPA_MAX_CODED_FRAME_SIZE; 
2288  
2289 
// Get header and restore sync word

2290 
header = AV_RB32(buf)  0xffe00000;

2291  
2292 
if (ff_mpa_check_header(header) < 0) { // Bad header, discard frame 
2293 
*data_size = 0;

2294 
return buf_size;

2295 
} 
2296  
2297 
ff_mpegaudio_decode_header((MPADecodeHeader *)s, header); 
2298 
/* update codec info */

2299 
avctx>sample_rate = s>sample_rate; 
2300 
avctx>channels = s>nb_channels; 
2301 
avctx>bit_rate = s>bit_rate; 
2302 
avctx>sub_id = s>layer; 
2303  
2304 
s>frame_size = len; 
2305  
2306 
if (avctx>parse_only) {

2307 
out_size = buf_size; 
2308 
} else {

2309 
out_size = mp_decode_frame(s, out_samples, buf, buf_size); 
2310 
} 
2311  
2312 
*data_size = out_size; 
2313 
return buf_size;

2314 
} 
2315 
#endif /* CONFIG_MP3ADU_DECODER */ 
2316  
2317 
#if CONFIG_MP3ON4_DECODER

2318  
2319 
/**

2320 
* Context for MP3On4 decoder

2321 
*/

2322 
typedef struct MP3On4DecodeContext { 
2323 
int frames; ///< number of mp3 frames per block (number of mp3 decoder instances) 
2324 
int syncword; ///< syncword patch 
2325 
const uint8_t *coff; ///< channels offsets in output buffer 
2326 
MPADecodeContext *mp3decctx[5]; ///< MPADecodeContext for every decoder instance 
2327 
} MP3On4DecodeContext; 
2328  
2329 
#include "mpeg4audio.h" 
2330  
2331 
/* Next 3 arrays are indexed by channel config number (passed via codecdata) */

2332 
static const uint8_t mp3Frames[8] = {0,1,1,2,3,3,4,5}; /* number of mp3 decoder instances */ 
2333 
/* offsets into output buffer, assume output order is FL FR BL BR C LFE */

2334 
static const uint8_t chan_offset[8][5] = { 
2335 
{0},

2336 
{0}, // C 
2337 
{0}, // FLR 
2338 
{2,0}, // C FLR 
2339 
{2,0,3}, // C FLR BS 
2340 
{4,0,2}, // C FLR BLRS 
2341 
{4,0,2,5}, // C FLR BLRS LFE 
2342 
{4,0,2,6,5}, // C FLR BLRS BLR LFE 
2343 
}; 
2344  
2345  
2346 
static int decode_init_mp3on4(AVCodecContext * avctx) 
2347 
{ 
2348 
MP3On4DecodeContext *s = avctx>priv_data; 
2349 
MPEG4AudioConfig cfg; 
2350 
int i;

2351  
2352 
if ((avctx>extradata_size < 2)  (avctx>extradata == NULL)) { 
2353 
av_log(avctx, AV_LOG_ERROR, "Codec extradata missing or too short.\n");

2354 
return 1; 
2355 
} 
2356  
2357 
ff_mpeg4audio_get_config(&cfg, avctx>extradata, avctx>extradata_size); 
2358 
if (!cfg.chan_config  cfg.chan_config > 7) { 
2359 
av_log(avctx, AV_LOG_ERROR, "Invalid channel config number.\n");

2360 
return 1; 
2361 
} 
2362 
s>frames = mp3Frames[cfg.chan_config]; 
2363 
s>coff = chan_offset[cfg.chan_config]; 
2364 
avctx>channels = ff_mpeg4audio_channels[cfg.chan_config]; 
2365  
2366 
if (cfg.sample_rate < 16000) 
2367 
s>syncword = 0xffe00000;

2368 
else

2369 
s>syncword = 0xfff00000;

2370  
2371 
/* Init the first mp3 decoder in standard way, so that all tables get builded

2372 
* We replace avctx>priv_data with the context of the first decoder so that

2373 
* decode_init() does not have to be changed.

2374 
* Other decoders will be initialized here copying data from the first context

2375 
*/

2376 
// Allocate zeroed memory for the first decoder context

2377 
s>mp3decctx[0] = av_mallocz(sizeof(MPADecodeContext)); 
2378 
// Put decoder context in place to make init_decode() happy

2379 
avctx>priv_data = s>mp3decctx[0];

2380 
decode_init(avctx); 
2381 
// Restore mp3on4 context pointer

2382 
avctx>priv_data = s; 
2383 
s>mp3decctx[0]>adu_mode = 1; // Set adu mode 
2384  
2385 
/* Create a separate codec/context for each frame (first is already ok).

2386 
* Each frame is 1 or 2 channels  up to 5 frames allowed

2387 
*/

2388 
for (i = 1; i < s>frames; i++) { 
2389 
s>mp3decctx[i] = av_mallocz(sizeof(MPADecodeContext));

2390 
s>mp3decctx[i]>compute_antialias = s>mp3decctx[0]>compute_antialias;

2391 
s>mp3decctx[i]>adu_mode = 1;

2392 
s>mp3decctx[i]>avctx = avctx; 
2393 
} 
2394  
2395 
return 0; 
2396 
} 
2397  
2398  
2399 
static av_cold int decode_close_mp3on4(AVCodecContext * avctx) 
2400 
{ 
2401 
MP3On4DecodeContext *s = avctx>priv_data; 
2402 
int i;

2403  
2404 
for (i = 0; i < s>frames; i++) 
2405 
if (s>mp3decctx[i])

2406 
av_free(s>mp3decctx[i]); 
2407  
2408 
return 0; 
2409 
} 
2410  
2411  
2412 
static int decode_frame_mp3on4(AVCodecContext * avctx, 
2413 
void *data, int *data_size, 
2414 
AVPacket *avpkt) 
2415 
{ 
2416 
const uint8_t *buf = avpkt>data;

2417 
int buf_size = avpkt>size;

2418 
MP3On4DecodeContext *s = avctx>priv_data; 
2419 
MPADecodeContext *m; 
2420 
int fsize, len = buf_size, out_size = 0; 
2421 
uint32_t header; 
2422 
OUT_INT *out_samples = data; 
2423 
OUT_INT decoded_buf[MPA_FRAME_SIZE * MPA_MAX_CHANNELS]; 
2424 
OUT_INT *outptr, *bp; 
2425 
int fr, j, n;

2426  
2427 
if(*data_size < MPA_FRAME_SIZE * MPA_MAX_CHANNELS * s>frames * sizeof(OUT_INT)) 
2428 
return 1; 
2429  
2430 
*data_size = 0;

2431 
// Discard too short frames

2432 
if (buf_size < HEADER_SIZE)

2433 
return 1; 
2434  
2435 
// If only one decoder interleave is not needed

2436 
outptr = s>frames == 1 ? out_samples : decoded_buf;

2437  
2438 
avctx>bit_rate = 0;

2439  
2440 
for (fr = 0; fr < s>frames; fr++) { 
2441 
fsize = AV_RB16(buf) >> 4;

2442 
fsize = FFMIN3(fsize, len, MPA_MAX_CODED_FRAME_SIZE); 
2443 
m = s>mp3decctx[fr]; 
2444 
assert (m != NULL);

2445  
2446 
header = (AV_RB32(buf) & 0x000fffff)  s>syncword; // patch header 
2447  
2448 
if (ff_mpa_check_header(header) < 0) // Bad header, discard block 
2449 
break;

2450  
2451 
ff_mpegaudio_decode_header((MPADecodeHeader *)m, header); 
2452 
out_size += mp_decode_frame(m, outptr, buf, fsize); 
2453 
buf += fsize; 
2454 
len = fsize; 
2455  
2456 
if(s>frames > 1) { 
2457 
n = m>avctx>frame_size*m>nb_channels; 
2458 
/* interleave output data */

2459 
bp = out_samples + s>coff[fr]; 
2460 
if(m>nb_channels == 1) { 
2461 
for(j = 0; j < n; j++) { 
2462 
*bp = decoded_buf[j]; 
2463 
bp += avctx>channels; 
2464 
} 
2465 
} else {

2466 
for(j = 0; j < n; j++) { 
2467 
bp[0] = decoded_buf[j++];

2468 
bp[1] = decoded_buf[j];

2469 
bp += avctx>channels; 
2470 
} 
2471 
} 
2472 
} 
2473 
avctx>bit_rate += m>bit_rate; 
2474 
} 
2475  
2476 
/* update codec info */

2477 
avctx>sample_rate = s>mp3decctx[0]>sample_rate;

2478  
2479 
*data_size = out_size; 
2480 
return buf_size;

2481 
} 
2482 
#endif /* CONFIG_MP3ON4_DECODER */ 
2483  
2484 
#if CONFIG_MP1_DECODER

2485 
AVCodec mp1_decoder = 
2486 
{ 
2487 
"mp1",

2488 
CODEC_TYPE_AUDIO, 
2489 
CODEC_ID_MP1, 
2490 
sizeof(MPADecodeContext),

2491 
decode_init, 
2492 
NULL,

2493 
NULL,

2494 
decode_frame, 
2495 
CODEC_CAP_PARSE_ONLY, 
2496 
.flush= flush, 
2497 
.long_name= NULL_IF_CONFIG_SMALL("MP1 (MPEG audio layer 1)"),

2498 
}; 
2499 
#endif

2500 
#if CONFIG_MP2_DECODER

2501 
AVCodec mp2_decoder = 
2502 
{ 
2503 
"mp2",

2504 
CODEC_TYPE_AUDIO, 
2505 
CODEC_ID_MP2, 
2506 
sizeof(MPADecodeContext),

2507 
decode_init, 
2508 
NULL,

2509 
NULL,

2510 
decode_frame, 
2511 
CODEC_CAP_PARSE_ONLY, 
2512 
.flush= flush, 
2513 
.long_name= NULL_IF_CONFIG_SMALL("MP2 (MPEG audio layer 2)"),

2514 
}; 
2515 
#endif

2516 
#if CONFIG_MP3_DECODER

2517 
AVCodec mp3_decoder = 
2518 
{ 
2519 
"mp3",

2520 
CODEC_TYPE_AUDIO, 
2521 
CODEC_ID_MP3, 
2522 
sizeof(MPADecodeContext),

2523 
decode_init, 
2524 
NULL,

2525 
NULL,

2526 
decode_frame, 
2527 
CODEC_CAP_PARSE_ONLY, 
2528 
.flush= flush, 
2529 
.long_name= NULL_IF_CONFIG_SMALL("MP3 (MPEG audio layer 3)"),

2530 
}; 
2531 
#endif

2532 
#if CONFIG_MP3ADU_DECODER

2533 
AVCodec mp3adu_decoder = 
2534 
{ 
2535 
"mp3adu",

2536 
CODEC_TYPE_AUDIO, 
2537 
CODEC_ID_MP3ADU, 
2538 
sizeof(MPADecodeContext),

2539 
decode_init, 
2540 
NULL,

2541 
NULL,

2542 
decode_frame_adu, 
2543 
CODEC_CAP_PARSE_ONLY, 
2544 
.flush= flush, 
2545 
.long_name= NULL_IF_CONFIG_SMALL("ADU (Application Data Unit) MP3 (MPEG audio layer 3)"),

2546 
}; 
2547 
#endif

2548 
#if CONFIG_MP3ON4_DECODER

2549 
AVCodec mp3on4_decoder = 
2550 
{ 
2551 
"mp3on4",

2552 
CODEC_TYPE_AUDIO, 
2553 
CODEC_ID_MP3ON4, 
2554 
sizeof(MP3On4DecodeContext),

2555 
decode_init_mp3on4, 
2556 
NULL,

2557 
decode_close_mp3on4, 
2558 
decode_frame_mp3on4, 
2559 
.flush= flush, 
2560 
.long_name= NULL_IF_CONFIG_SMALL("MP3onMP4"),

2561 
}; 
2562 
#endif
