ffmpeg / libavcodec / mpegaudiodec.c @ 9106a698
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1 
/*


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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.

35 
*/

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

43 
#define FIXR(a) ((int)((a) * FRAC_ONE + 0.5)) 
44 
#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  
50 
#define HEADER_SIZE 4 
51  
52 
/* layer 3 "granule" */

53 
typedef struct GranuleDef { 
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uint8_t scfsi; 
55 
int part2_3_length;

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int big_values;

57 
int global_gain;

58 
int scalefac_compress;

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uint8_t block_type; 
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uint8_t switch_point; 
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int table_select[3]; 
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int subblock_gain[3]; 
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uint8_t scalefac_scale; 
64 
uint8_t count1table_select; 
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int region_size[3]; /* number of huffman codes in each region */ 
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int preflag;

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

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int32_t sb_hybrid[SBLIMIT * 18]; /* 576 samples */ 
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} GranuleDef; 
71  
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#include "mpegaudiodata.h" 
73 
#include "mpegaudiodectab.h" 
74  
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static void compute_antialias_integer(MPADecodeContext *s, GranuleDef *g); 
76 
static void compute_antialias_float(MPADecodeContext *s, GranuleDef *g); 
77  
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/* vlc structure for decoding layer 3 huffman tables */

79 
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 
83 
][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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}; 
88 
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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}; 
93 
/* computed from band_size_long */

94 
static uint16_t band_index_long[9][23]; 
95 
/* XXX: free when all decoders are closed */

96 
#define TABLE_4_3_SIZE (8191 + 16)*4 
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static int8_t table_4_3_exp[TABLE_4_3_SIZE];

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static uint32_t table_4_3_value[TABLE_4_3_SIZE];

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

102 
static int32_t is_table[2][16]; 
103 
static int32_t is_table_lsf[2][2][16]; 
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static int32_t csa_table[8][4]; 
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static float csa_table_float[8][4]; 
106 
static int32_t mdct_win[8][36]; 
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/* lower 2 bits: modulo 3, higher bits: shift */

109 
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]; 
112 
/* mult table for layer 2 group quantization */

113  
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#define SCALE_GEN(v) \

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{ FIXR(1.0 * (v)), FIXR(0.7937005259 * (v)), FIXR(0.6299605249 * (v)) } 
116  
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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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}; 
122  
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static DECLARE_ALIGNED_16(MPA_INT, window[512]); 
124  
125 
/**

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* Convert region offsets to region sizes and truncate

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* size to big_values.

128 
*/

129 
void ff_region_offset2size(GranuleDef *g){

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int i, k, j=0; 
131 
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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} 
137 
} 
138  
139 
void ff_init_short_region(MPADecodeContext *s, GranuleDef *g){

140 
if (g>block_type == 2) 
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g>region_size[0] = (36 / 2); 
142 
else {

143 
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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} 
152  
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void ff_init_long_region(MPADecodeContext *s, GranuleDef *g, int ra1, int ra2){ 
154 
int l;

155 
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 */

158 
l = FFMIN(ra1 + ra2 + 2, 22); 
159 
g>region_size[1] =

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

161 
} 
162  
163 
void ff_compute_band_indexes(MPADecodeContext *s, GranuleDef *g){

164 
if (g>block_type == 2) { 
165 
if (g>switch_point) {

166 
/* 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!) */

169 
if (s>sample_rate_index <= 2) 
170 
g>long_end = 8;

171 
else if (s>sample_rate_index != 8) 
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g>long_end = 6;

173 
else

174 
g>long_end = 4; /* 8000 Hz */ 
175  
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g>short_start = 2 + (s>sample_rate_index != 8); 
177 
} else {

178 
g>long_end = 0;

179 
g>short_start = 0;

180 
} 
181 
} else {

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g>short_start = 13;

183 
g>long_end = 22;

184 
} 
185 
} 
186  
187 
/* layer 1 unscaling */

188 
/* n = number of bits of the mantissa minus 1 */

189 
static inline int l1_unscale(int n, int mant, int scale_factor) 
190 
{ 
191 
int shift, mod;

192 
int64_t val; 
193  
194 
shift = scale_factor_modshift[scale_factor]; 
195 
mod = shift & 3;

196 
shift >>= 2;

197 
val = MUL64(mant + (1 << n) + 1, scale_factor_mult[n1][mod]); 
198 
shift += n; 
199 
/* NOTE: at this point, 1 <= shift >= 21 + 15 */

200 
return (int)((val + (1LL << (shift  1))) >> shift); 
201 
} 
202  
203 
static inline int l2_unscale_group(int steps, int mant, int scale_factor) 
204 
{ 
205 
int shift, mod, val;

206  
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shift = scale_factor_modshift[scale_factor]; 
208 
mod = shift & 3;

209 
shift >>= 2;

210  
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val = (mant  (steps >> 1)) * scale_factor_mult2[steps >> 2][mod]; 
212 
/* NOTE: at this point, 0 <= shift <= 21 */

213 
if (shift > 0) 
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val = (val + (1 << (shift  1))) >> shift; 
215 
return val;

216 
} 
217  
218 
/* compute value^(4/3) * 2^(exponent/4). It normalized to FRAC_BITS */

219 
static inline int l3_unscale(int value, int exponent) 
220 
{ 
221 
unsigned int m; 
222 
int e;

223  
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e = table_4_3_exp [4*value + (exponent&3)]; 
225 
m = table_4_3_value[4*value + (exponent&3)]; 
226 
e = (exponent >> 2);

227 
assert(e>=1);

228 
if (e > 31) 
229 
return 0; 
230 
m = (m + (1 << (e1))) >> e; 
231  
232 
return m;

233 
} 
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235 
/* all integer n^(4/3) computation code */

236 
#define DEV_ORDER 13 
237  
238 
#define POW_FRAC_BITS 24 
239 
#define POW_FRAC_ONE (1 << POW_FRAC_BITS) 
240 
#define POW_FIX(a) ((int)((a) * POW_FRAC_ONE)) 
241 
#define POW_MULL(a,b) (((int64_t)(a) * (int64_t)(b)) >> POW_FRAC_BITS)

242  
243 
static int dev_4_3_coefs[DEV_ORDER]; 
244  
245 
#if 0 /* unused */

246 
static int pow_mult3[3] = {

247 
POW_FIX(1.0),

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POW_FIX(1.25992104989487316476),

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POW_FIX(1.58740105196819947474),

250 
};

251 
#endif

252  
253 
static av_cold void int_pow_init(void) 
254 
{ 
255 
int i, a;

256  
257 
a = POW_FIX(1.0); 
258 
for(i=0;i<DEV_ORDER;i++) { 
259 
a = POW_MULL(a, POW_FIX(4.0 / 3.0)  i * POW_FIX(1.0)) / (i + 1); 
260 
dev_4_3_coefs[i] = a; 
261 
} 
262 
} 
263  
264 
#if 0 /* unused, remove? */

265 
/* return the mantissa and the binary exponent */

266 
static int int_pow(int i, int *exp_ptr)

267 
{

268 
int e, er, eq, j;

269 
int a, a1;

270 

271 
/* renormalize */

272 
a = i;

273 
e = POW_FRAC_BITS;

274 
while (a < (1 << (POW_FRAC_BITS  1))) {

275 
a = a << 1;

276 
e;

277 
}

278 
a = (1 << POW_FRAC_BITS);

279 
a1 = 0;

280 
for(j = DEV_ORDER  1; j >= 0; j)

281 
a1 = POW_MULL(a, dev_4_3_coefs[j] + a1);

282 
a = (1 << POW_FRAC_BITS) + a1;

283 
/* exponent compute (exact) */

284 
e = e * 4;

285 
er = e % 3;

286 
eq = e / 3;

287 
a = POW_MULL(a, pow_mult3[er]);

288 
while (a >= 2 * POW_FRAC_ONE) {

289 
a = a >> 1;

290 
eq++;

291 
}

292 
/* convert to float */

293 
while (a < POW_FRAC_ONE) {

294 
a = a << 1;

295 
eq;

296 
}

297 
/* now POW_FRAC_ONE <= a < 2 * POW_FRAC_ONE */

298 
#if POW_FRAC_BITS > FRAC_BITS

299 
a = (a + (1 << (POW_FRAC_BITS  FRAC_BITS  1))) >> (POW_FRAC_BITS  FRAC_BITS);

300 
/* correct overflow */

301 
if (a >= 2 * (1 << FRAC_BITS)) {

302 
a = a >> 1;

303 
eq++;

304 
}

305 
#endif

306 
*exp_ptr = eq; 
307 
return a;

308 
} 
309 
#endif

310  
311 
static av_cold int decode_init(AVCodecContext * avctx) 
312 
{ 
313 
MPADecodeContext *s = avctx>priv_data; 
314 
static int init=0; 
315 
int i, j, k;

316  
317 
s>avctx = avctx; 
318  
319 
avctx>sample_fmt= OUT_FMT; 
320 
s>error_recognition= avctx>error_recognition; 
321  
322 
if(avctx>antialias_algo != FF_AA_FLOAT)

323 
s>compute_antialias= compute_antialias_integer; 
324 
else

325 
s>compute_antialias= compute_antialias_float; 
326  
327 
if (!init && !avctx>parse_only) {

328 
int offset;

329  
330 
/* scale factors table for layer 1/2 */

331 
for(i=0;i<64;i++) { 
332 
int shift, mod;

333 
/* 1.0 (i = 3) is normalized to 2 ^ FRAC_BITS */

334 
shift = (i / 3);

335 
mod = i % 3;

336 
scale_factor_modshift[i] = mod  (shift << 2);

337 
} 
338  
339 
/* scale factor multiply for layer 1 */

340 
for(i=0;i<15;i++) { 
341 
int n, norm;

342 
n = i + 2;

343 
norm = ((INT64_C(1) << n) * FRAC_ONE) / ((1 << n)  1); 
344 
scale_factor_mult[i][0] = MULL(FIXR(1.0 * 2.0), norm, FRAC_BITS); 
345 
scale_factor_mult[i][1] = MULL(FIXR(0.7937005259 * 2.0), norm, FRAC_BITS); 
346 
scale_factor_mult[i][2] = MULL(FIXR(0.6299605249 * 2.0), norm, FRAC_BITS); 
347 
dprintf(avctx, "%d: norm=%x s=%x %x %x\n",

348 
i, norm, 
349 
scale_factor_mult[i][0],

350 
scale_factor_mult[i][1],

351 
scale_factor_mult[i][2]);

352 
} 
353  
354 
ff_mpa_synth_init(window); 
355  
356 
/* huffman decode tables */

357 
offset = 0;

358 
for(i=1;i<16;i++) { 
359 
const HuffTable *h = &mpa_huff_tables[i];

360 
int xsize, x, y;

361 
unsigned int n; 
362 
uint8_t tmp_bits [512];

363 
uint16_t tmp_codes[512];

364  
365 
memset(tmp_bits , 0, sizeof(tmp_bits )); 
366 
memset(tmp_codes, 0, sizeof(tmp_codes)); 
367  
368 
xsize = h>xsize; 
369 
n = xsize * xsize; 
370  
371 
j = 0;

372 
for(x=0;x<xsize;x++) { 
373 
for(y=0;y<xsize;y++){ 
374 
tmp_bits [(x << 5)  y  ((x&&y)<<4)]= h>bits [j ]; 
375 
tmp_codes[(x << 5)  y  ((x&&y)<<4)]= h>codes[j++]; 
376 
} 
377 
} 
378  
379 
/* XXX: fail test */

380 
huff_vlc[i].table = huff_vlc_tables+offset; 
381 
huff_vlc[i].table_allocated = huff_vlc_tables_sizes[i]; 
382 
init_vlc(&huff_vlc[i], 7, 512, 
383 
tmp_bits, 1, 1, tmp_codes, 2, 2, 
384 
INIT_VLC_USE_NEW_STATIC); 
385 
offset += huff_vlc_tables_sizes[i]; 
386 
} 
387 
assert(offset == FF_ARRAY_ELEMS(huff_vlc_tables)); 
388  
389 
offset = 0;

390 
for(i=0;i<2;i++) { 
391 
huff_quad_vlc[i].table = huff_quad_vlc_tables+offset; 
392 
huff_quad_vlc[i].table_allocated = huff_quad_vlc_tables_sizes[i]; 
393 
init_vlc(&huff_quad_vlc[i], i == 0 ? 7 : 4, 16, 
394 
mpa_quad_bits[i], 1, 1, mpa_quad_codes[i], 1, 1, 
395 
INIT_VLC_USE_NEW_STATIC); 
396 
offset += huff_quad_vlc_tables_sizes[i]; 
397 
} 
398 
assert(offset == FF_ARRAY_ELEMS(huff_quad_vlc_tables)); 
399  
400 
for(i=0;i<9;i++) { 
401 
k = 0;

402 
for(j=0;j<22;j++) { 
403 
band_index_long[i][j] = k; 
404 
k += band_size_long[i][j]; 
405 
} 
406 
band_index_long[i][22] = k;

407 
} 
408  
409 
/* compute n ^ (4/3) and store it in mantissa/exp format */

410  
411 
int_pow_init(); 
412 
for(i=1;i<TABLE_4_3_SIZE;i++) { 
413 
double f, fm;

414 
int e, m;

415 
f = pow((double)(i/4), 4.0 / 3.0) * pow(2, (i&3)*0.25); 
416 
fm = frexp(f, &e); 
417 
m = (uint32_t)(fm*(1LL<<31) + 0.5); 
418 
e+= FRAC_BITS  31 + 5  100; 
419  
420 
/* normalized to FRAC_BITS */

421 
table_4_3_value[i] = m; 
422 
table_4_3_exp[i] = e; 
423 
} 
424 
for(i=0; i<512*16; i++){ 
425 
int exponent= (i>>4); 
426 
double f= pow(i&15, 4.0 / 3.0) * pow(2, (exponent400)*0.25 + FRAC_BITS + 5); 
427 
expval_table[exponent][i&15]= llrint(f);

428 
if((i&15)==1) 
429 
exp_table[exponent]= llrint(f); 
430 
} 
431  
432 
for(i=0;i<7;i++) { 
433 
float f;

434 
int v;

435 
if (i != 6) { 
436 
f = tan((double)i * M_PI / 12.0); 
437 
v = FIXR(f / (1.0 + f)); 
438 
} else {

439 
v = FIXR(1.0); 
440 
} 
441 
is_table[0][i] = v;

442 
is_table[1][6  i] = v; 
443 
} 
444 
/* invalid values */

445 
for(i=7;i<16;i++) 
446 
is_table[0][i] = is_table[1][i] = 0.0; 
447  
448 
for(i=0;i<16;i++) { 
449 
double f;

450 
int e, k;

451  
452 
for(j=0;j<2;j++) { 
453 
e = (j + 1) * ((i + 1) >> 1); 
454 
f = pow(2.0, e / 4.0); 
455 
k = i & 1;

456 
is_table_lsf[j][k ^ 1][i] = FIXR(f);

457 
is_table_lsf[j][k][i] = FIXR(1.0); 
458 
dprintf(avctx, "is_table_lsf %d %d: %x %x\n",

459 
i, j, is_table_lsf[j][0][i], is_table_lsf[j][1][i]); 
460 
} 
461 
} 
462  
463 
for(i=0;i<8;i++) { 
464 
float ci, cs, ca;

465 
ci = ci_table[i]; 
466 
cs = 1.0 / sqrt(1.0 + ci * ci); 
467 
ca = cs * ci; 
468 
csa_table[i][0] = FIXHR(cs/4); 
469 
csa_table[i][1] = FIXHR(ca/4); 
470 
csa_table[i][2] = FIXHR(ca/4) + FIXHR(cs/4); 
471 
csa_table[i][3] = FIXHR(ca/4)  FIXHR(cs/4); 
472 
csa_table_float[i][0] = cs;

473 
csa_table_float[i][1] = ca;

474 
csa_table_float[i][2] = ca + cs;

475 
csa_table_float[i][3] = ca  cs;

476 
} 
477  
478 
/* compute mdct windows */

479 
for(i=0;i<36;i++) { 
480 
for(j=0; j<4; j++){ 
481 
double d;

482  
483 
if(j==2 && i%3 != 1) 
484 
continue;

485  
486 
d= sin(M_PI * (i + 0.5) / 36.0); 
487 
if(j==1){ 
488 
if (i>=30) d= 0; 
489 
else if(i>=24) d= sin(M_PI * (i  18 + 0.5) / 12.0); 
490 
else if(i>=18) d= 1; 
491 
}else if(j==3){ 
492 
if (i< 6) d= 0; 
493 
else if(i< 12) d= sin(M_PI * (i  6 + 0.5) / 12.0); 
494 
else if(i< 18) d= 1; 
495 
} 
496 
//merge last stage of imdct into the window coefficients

497 
d*= 0.5 / cos(M_PI*(2*i + 19)/72); 
498  
499 
if(j==2) 
500 
mdct_win[j][i/3] = FIXHR((d / (1<<5))); 
501 
else

502 
mdct_win[j][i ] = FIXHR((d / (1<<5))); 
503 
} 
504 
} 
505  
506 
/* NOTE: we do frequency inversion adter the MDCT by changing

507 
the sign of the right window coefs */

508 
for(j=0;j<4;j++) { 
509 
for(i=0;i<36;i+=2) { 
510 
mdct_win[j + 4][i] = mdct_win[j][i];

511 
mdct_win[j + 4][i + 1] = mdct_win[j][i + 1]; 
512 
} 
513 
} 
514  
515 
init = 1;

516 
} 
517  
518 
if (avctx>codec_id == CODEC_ID_MP3ADU)

519 
s>adu_mode = 1;

520 
return 0; 
521 
} 
522  
523 
/* tab[i][j] = 1.0 / (2.0 * cos(pi*(2*k+1) / 2^(6  j))) */

524  
525 
/* cos(i*pi/64) */

526  
527 
#define COS0_0 FIXHR(0.50060299823519630134/2) 
528 
#define COS0_1 FIXHR(0.50547095989754365998/2) 
529 
#define COS0_2 FIXHR(0.51544730992262454697/2) 
530 
#define COS0_3 FIXHR(0.53104259108978417447/2) 
531 
#define COS0_4 FIXHR(0.55310389603444452782/2) 
532 
#define COS0_5 FIXHR(0.58293496820613387367/2) 
533 
#define COS0_6 FIXHR(0.62250412303566481615/2) 
534 
#define COS0_7 FIXHR(0.67480834145500574602/2) 
535 
#define COS0_8 FIXHR(0.74453627100229844977/2) 
536 
#define COS0_9 FIXHR(0.83934964541552703873/2) 
537 
#define COS0_10 FIXHR(0.97256823786196069369/2) 
538 
#define COS0_11 FIXHR(1.16943993343288495515/4) 
539 
#define COS0_12 FIXHR(1.48416461631416627724/4) 
540 
#define COS0_13 FIXHR(2.05778100995341155085/8) 
541 
#define COS0_14 FIXHR(3.40760841846871878570/8) 
542 
#define COS0_15 FIXHR(10.19000812354805681150/32) 
543  
544 
#define COS1_0 FIXHR(0.50241928618815570551/2) 
545 
#define COS1_1 FIXHR(0.52249861493968888062/2) 
546 
#define COS1_2 FIXHR(0.56694403481635770368/2) 
547 
#define COS1_3 FIXHR(0.64682178335999012954/2) 
548 
#define COS1_4 FIXHR(0.78815462345125022473/2) 
549 
#define COS1_5 FIXHR(1.06067768599034747134/4) 
550 
#define COS1_6 FIXHR(1.72244709823833392782/4) 
551 
#define COS1_7 FIXHR(5.10114861868916385802/16) 
552  
553 
#define COS2_0 FIXHR(0.50979557910415916894/2) 
554 
#define COS2_1 FIXHR(0.60134488693504528054/2) 
555 
#define COS2_2 FIXHR(0.89997622313641570463/2) 
556 
#define COS2_3 FIXHR(2.56291544774150617881/8) 
557  
558 
#define COS3_0 FIXHR(0.54119610014619698439/2) 
559 
#define COS3_1 FIXHR(1.30656296487637652785/4) 
560  
561 
#define COS4_0 FIXHR(0.70710678118654752439/2) 
562  
563 
/* butterfly operator */

564 
#define BF(a, b, c, s)\

565 
{\ 
566 
tmp0 = tab[a] + tab[b];\ 
567 
tmp1 = tab[a]  tab[b];\ 
568 
tab[a] = tmp0;\ 
569 
tab[b] = MULH(tmp1<<(s), c);\ 
570 
} 
571  
572 
#define BF1(a, b, c, d)\

573 
{\ 
574 
BF(a, b, COS4_0, 1);\

575 
BF(c, d,COS4_0, 1);\

576 
tab[c] += tab[d];\ 
577 
} 
578  
579 
#define BF2(a, b, c, d)\

580 
{\ 
581 
BF(a, b, COS4_0, 1);\

582 
BF(c, d,COS4_0, 1);\

583 
tab[c] += tab[d];\ 
584 
tab[a] += tab[c];\ 
585 
tab[c] += tab[b];\ 
586 
tab[b] += tab[d];\ 
587 
} 
588  
589 
#define ADD(a, b) tab[a] += tab[b]

590  
591 
/* DCT32 without 1/sqrt(2) coef zero scaling. */

592 
static void dct32(int32_t *out, int32_t *tab) 
593 
{ 
594 
int tmp0, tmp1;

595  
596 
/* pass 1 */

597 
BF( 0, 31, COS0_0 , 1); 
598 
BF(15, 16, COS0_15, 5); 
599 
/* pass 2 */

600 
BF( 0, 15, COS1_0 , 1); 
601 
BF(16, 31,COS1_0 , 1); 
602 
/* pass 1 */

603 
BF( 7, 24, COS0_7 , 1); 
604 
BF( 8, 23, COS0_8 , 1); 
605 
/* pass 2 */

606 
BF( 7, 8, COS1_7 , 4); 
607 
BF(23, 24,COS1_7 , 4); 
608 
/* pass 3 */

609 
BF( 0, 7, COS2_0 , 1); 
610 
BF( 8, 15,COS2_0 , 1); 
611 
BF(16, 23, COS2_0 , 1); 
612 
BF(24, 31,COS2_0 , 1); 
613 
/* pass 1 */

614 
BF( 3, 28, COS0_3 , 1); 
615 
BF(12, 19, COS0_12, 2); 
616 
/* pass 2 */

617 
BF( 3, 12, COS1_3 , 1); 
618 
BF(19, 28,COS1_3 , 1); 
619 
/* pass 1 */

620 
BF( 4, 27, COS0_4 , 1); 
621 
BF(11, 20, COS0_11, 2); 
622 
/* pass 2 */

623 
BF( 4, 11, COS1_4 , 1); 
624 
BF(20, 27,COS1_4 , 1); 
625 
/* pass 3 */

626 
BF( 3, 4, COS2_3 , 3); 
627 
BF(11, 12,COS2_3 , 3); 
628 
BF(19, 20, COS2_3 , 3); 
629 
BF(27, 28,COS2_3 , 3); 
630 
/* pass 4 */

631 
BF( 0, 3, COS3_0 , 1); 
632 
BF( 4, 7,COS3_0 , 1); 
633 
BF( 8, 11, COS3_0 , 1); 
634 
BF(12, 15,COS3_0 , 1); 
635 
BF(16, 19, COS3_0 , 1); 
636 
BF(20, 23,COS3_0 , 1); 
637 
BF(24, 27, COS3_0 , 1); 
638 
BF(28, 31,COS3_0 , 1); 
639  
640  
641  
642 
/* pass 1 */

643 
BF( 1, 30, COS0_1 , 1); 
644 
BF(14, 17, COS0_14, 3); 
645 
/* pass 2 */

646 
BF( 1, 14, COS1_1 , 1); 
647 
BF(17, 30,COS1_1 , 1); 
648 
/* pass 1 */

649 
BF( 6, 25, COS0_6 , 1); 
650 
BF( 9, 22, COS0_9 , 1); 
651 
/* pass 2 */

652 
BF( 6, 9, COS1_6 , 2); 
653 
BF(22, 25,COS1_6 , 2); 
654 
/* pass 3 */

655 
BF( 1, 6, COS2_1 , 1); 
656 
BF( 9, 14,COS2_1 , 1); 
657 
BF(17, 22, COS2_1 , 1); 
658 
BF(25, 30,COS2_1 , 1); 
659  
660 
/* pass 1 */

661 
BF( 2, 29, COS0_2 , 1); 
662 
BF(13, 18, COS0_13, 3); 
663 
/* pass 2 */

664 
BF( 2, 13, COS1_2 , 1); 
665 
BF(18, 29,COS1_2 , 1); 
666 
/* pass 1 */

667 
BF( 5, 26, COS0_5 , 1); 
668 
BF(10, 21, COS0_10, 1); 
669 
/* pass 2 */

670 
BF( 5, 10, COS1_5 , 2); 
671 
BF(21, 26,COS1_5 , 2); 
672 
/* pass 3 */

673 
BF( 2, 5, COS2_2 , 1); 
674 
BF(10, 13,COS2_2 , 1); 
675 
BF(18, 21, COS2_2 , 1); 
676 
BF(26, 29,COS2_2 , 1); 
677 
/* pass 4 */

678 
BF( 1, 2, COS3_1 , 2); 
679 
BF( 5, 6,COS3_1 , 2); 
680 
BF( 9, 10, COS3_1 , 2); 
681 
BF(13, 14,COS3_1 , 2); 
682 
BF(17, 18, COS3_1 , 2); 
683 
BF(21, 22,COS3_1 , 2); 
684 
BF(25, 26, COS3_1 , 2); 
685 
BF(29, 30,COS3_1 , 2); 
686  
687 
/* pass 5 */

688 
BF1( 0, 1, 2, 3); 
689 
BF2( 4, 5, 6, 7); 
690 
BF1( 8, 9, 10, 11); 
691 
BF2(12, 13, 14, 15); 
692 
BF1(16, 17, 18, 19); 
693 
BF2(20, 21, 22, 23); 
694 
BF1(24, 25, 26, 27); 
695 
BF2(28, 29, 30, 31); 
696  
697 
/* pass 6 */

698  
699 
ADD( 8, 12); 
700 
ADD(12, 10); 
701 
ADD(10, 14); 
702 
ADD(14, 9); 
703 
ADD( 9, 13); 
704 
ADD(13, 11); 
705 
ADD(11, 15); 
706  
707 
out[ 0] = tab[0]; 
708 
out[16] = tab[1]; 
709 
out[ 8] = tab[2]; 
710 
out[24] = tab[3]; 
711 
out[ 4] = tab[4]; 
712 
out[20] = tab[5]; 
713 
out[12] = tab[6]; 
714 
out[28] = tab[7]; 
715 
out[ 2] = tab[8]; 
716 
out[18] = tab[9]; 
717 
out[10] = tab[10]; 
718 
out[26] = tab[11]; 
719 
out[ 6] = tab[12]; 
720 
out[22] = tab[13]; 
721 
out[14] = tab[14]; 
722 
out[30] = tab[15]; 
723  
724 
ADD(24, 28); 
725 
ADD(28, 26); 
726 
ADD(26, 30); 
727 
ADD(30, 25); 
728 
ADD(25, 29); 
729 
ADD(29, 27); 
730 
ADD(27, 31); 
731  
732 
out[ 1] = tab[16] + tab[24]; 
733 
out[17] = tab[17] + tab[25]; 
734 
out[ 9] = tab[18] + tab[26]; 
735 
out[25] = tab[19] + tab[27]; 
736 
out[ 5] = tab[20] + tab[28]; 
737 
out[21] = tab[21] + tab[29]; 
738 
out[13] = tab[22] + tab[30]; 
739 
out[29] = tab[23] + tab[31]; 
740 
out[ 3] = tab[24] + tab[20]; 
741 
out[19] = tab[25] + tab[21]; 
742 
out[11] = tab[26] + tab[22]; 
743 
out[27] = tab[27] + tab[23]; 
744 
out[ 7] = tab[28] + tab[18]; 
745 
out[23] = tab[29] + tab[19]; 
746 
out[15] = tab[30] + tab[17]; 
747 
out[31] = tab[31]; 
748 
} 
749  
750 
#if FRAC_BITS <= 15 
751  
752 
static inline int round_sample(int *sum) 
753 
{ 
754 
int sum1;

755 
sum1 = (*sum) >> OUT_SHIFT; 
756 
*sum &= (1<<OUT_SHIFT)1; 
757 
if (sum1 < OUT_MIN)

758 
sum1 = OUT_MIN; 
759 
else if (sum1 > OUT_MAX) 
760 
sum1 = OUT_MAX; 
761 
return sum1;

762 
} 
763  
764 
/* signed 16x16 > 32 multiply add accumulate */

765 
#define MACS(rt, ra, rb) MAC16(rt, ra, rb)

766  
767 
/* signed 16x16 > 32 multiply */

768 
#define MULS(ra, rb) MUL16(ra, rb)

769  
770 
#define MLSS(rt, ra, rb) MLS16(rt, ra, rb)

771  
772 
#else

773  
774 
static inline int round_sample(int64_t *sum) 
775 
{ 
776 
int sum1;

777 
sum1 = (int)((*sum) >> OUT_SHIFT);

778 
*sum &= (1<<OUT_SHIFT)1; 
779 
if (sum1 < OUT_MIN)

780 
sum1 = OUT_MIN; 
781 
else if (sum1 > OUT_MAX) 
782 
sum1 = OUT_MAX; 
783 
return sum1;

784 
} 
785  
786 
# define MULS(ra, rb) MUL64(ra, rb)

787 
# define MACS(rt, ra, rb) MAC64(rt, ra, rb)

788 
# define MLSS(rt, ra, rb) MLS64(rt, ra, rb)

789 
#endif

790  
791 
#define SUM8(op, sum, w, p) \

792 
{ \ 
793 
op(sum, (w)[0 * 64], p[0 * 64]); \ 
794 
op(sum, (w)[1 * 64], p[1 * 64]); \ 
795 
op(sum, (w)[2 * 64], p[2 * 64]); \ 
796 
op(sum, (w)[3 * 64], p[3 * 64]); \ 
797 
op(sum, (w)[4 * 64], p[4 * 64]); \ 
798 
op(sum, (w)[5 * 64], p[5 * 64]); \ 
799 
op(sum, (w)[6 * 64], p[6 * 64]); \ 
800 
op(sum, (w)[7 * 64], p[7 * 64]); \ 
801 
} 
802  
803 
#define SUM8P2(sum1, op1, sum2, op2, w1, w2, p) \

804 
{ \ 
805 
int tmp;\

806 
tmp = p[0 * 64];\ 
807 
op1(sum1, (w1)[0 * 64], tmp);\ 
808 
op2(sum2, (w2)[0 * 64], tmp);\ 
809 
tmp = p[1 * 64];\ 
810 
op1(sum1, (w1)[1 * 64], tmp);\ 
811 
op2(sum2, (w2)[1 * 64], tmp);\ 
812 
tmp = p[2 * 64];\ 
813 
op1(sum1, (w1)[2 * 64], tmp);\ 
814 
op2(sum2, (w2)[2 * 64], tmp);\ 
815 
tmp = p[3 * 64];\ 
816 
op1(sum1, (w1)[3 * 64], tmp);\ 
817 
op2(sum2, (w2)[3 * 64], tmp);\ 
818 
tmp = p[4 * 64];\ 
819 
op1(sum1, (w1)[4 * 64], tmp);\ 
820 
op2(sum2, (w2)[4 * 64], tmp);\ 
821 
tmp = p[5 * 64];\ 
822 
op1(sum1, (w1)[5 * 64], tmp);\ 
823 
op2(sum2, (w2)[5 * 64], tmp);\ 
824 
tmp = p[6 * 64];\ 
825 
op1(sum1, (w1)[6 * 64], tmp);\ 
826 
op2(sum2, (w2)[6 * 64], tmp);\ 
827 
tmp = p[7 * 64];\ 
828 
op1(sum1, (w1)[7 * 64], tmp);\ 
829 
op2(sum2, (w2)[7 * 64], tmp);\ 
830 
} 
831  
832 
void av_cold ff_mpa_synth_init(MPA_INT *window)

833 
{ 
834 
int i;

835  
836 
/* max = 18760, max sum over all 16 coefs : 44736 */

837 
for(i=0;i<257;i++) { 
838 
int v;

839 
v = ff_mpa_enwindow[i]; 
840 
#if WFRAC_BITS < 16 
841 
v = (v + (1 << (16  WFRAC_BITS  1))) >> (16  WFRAC_BITS); 
842 
#endif

843 
window[i] = v; 
844 
if ((i & 63) != 0) 
845 
v = v; 
846 
if (i != 0) 
847 
window[512  i] = v;

848 
} 
849 
} 
850  
851 
/* 32 sub band synthesis filter. Input: 32 sub band samples, Output:

852 
32 samples. */

853 
/* XXX: optimize by avoiding ring buffer usage */

854 
void ff_mpa_synth_filter(MPA_INT *synth_buf_ptr, int *synth_buf_offset, 
855 
MPA_INT *window, int *dither_state,

856 
OUT_INT *samples, int incr,

857 
int32_t sb_samples[SBLIMIT]) 
858 
{ 
859 
int32_t tmp[32];

860 
register MPA_INT *synth_buf;

861 
register const MPA_INT *w, *w2, *p; 
862 
int j, offset, v;

863 
OUT_INT *samples2; 
864 
#if FRAC_BITS <= 15 
865 
int sum, sum2;

866 
#else

867 
int64_t sum, sum2; 
868 
#endif

869  
870 
dct32(tmp, sb_samples); 
871  
872 
offset = *synth_buf_offset; 
873 
synth_buf = synth_buf_ptr + offset; 
874  
875 
for(j=0;j<32;j++) { 
876 
v = tmp[j]; 
877 
#if FRAC_BITS <= 15 
878 
/* NOTE: can cause a loss in precision if very high amplitude

879 
sound */

880 
v = av_clip_int16(v); 
881 
#endif

882 
synth_buf[j] = v; 
883 
} 
884 
/* copy to avoid wrap */

885 
memcpy(synth_buf + 512, synth_buf, 32 * sizeof(MPA_INT)); 
886  
887 
samples2 = samples + 31 * incr;

888 
w = window; 
889 
w2 = window + 31;

890  
891 
sum = *dither_state; 
892 
p = synth_buf + 16;

893 
SUM8(MACS, sum, w, p); 
894 
p = synth_buf + 48;

895 
SUM8(MLSS, sum, w + 32, p);

896 
*samples = round_sample(&sum); 
897 
samples += incr; 
898 
w++; 
899  
900 
/* we calculate two samples at the same time to avoid one memory

901 
access per two sample */

902 
for(j=1;j<16;j++) { 
903 
sum2 = 0;

904 
p = synth_buf + 16 + j;

905 
SUM8P2(sum, MACS, sum2, MLSS, w, w2, p); 
906 
p = synth_buf + 48  j;

907 
SUM8P2(sum, MLSS, sum2, MLSS, w + 32, w2 + 32, p); 
908  
909 
*samples = round_sample(&sum); 
910 
samples += incr; 
911 
sum += sum2; 
912 
*samples2 = round_sample(&sum); 
913 
samples2 = incr; 
914 
w++; 
915 
w2; 
916 
} 
917  
918 
p = synth_buf + 32;

919 
SUM8(MLSS, sum, w + 32, p);

920 
*samples = round_sample(&sum); 
921 
*dither_state= sum; 
922  
923 
offset = (offset  32) & 511; 
924 
*synth_buf_offset = offset; 
925 
} 
926  
927 
#define C3 FIXHR(0.86602540378443864676/2) 
928  
929 
/* 0.5 / cos(pi*(2*i+1)/36) */

930 
static const int icos36[9] = { 
931 
FIXR(0.50190991877167369479), 
932 
FIXR(0.51763809020504152469), //0 
933 
FIXR(0.55168895948124587824), 
934 
FIXR(0.61038729438072803416), 
935 
FIXR(0.70710678118654752439), //1 
936 
FIXR(0.87172339781054900991), 
937 
FIXR(1.18310079157624925896), 
938 
FIXR(1.93185165257813657349), //2 
939 
FIXR(5.73685662283492756461), 
940 
}; 
941  
942 
/* 0.5 / cos(pi*(2*i+1)/36) */

943 
static const int icos36h[9] = { 
944 
FIXHR(0.50190991877167369479/2), 
945 
FIXHR(0.51763809020504152469/2), //0 
946 
FIXHR(0.55168895948124587824/2), 
947 
FIXHR(0.61038729438072803416/2), 
948 
FIXHR(0.70710678118654752439/2), //1 
949 
FIXHR(0.87172339781054900991/2), 
950 
FIXHR(1.18310079157624925896/4), 
951 
FIXHR(1.93185165257813657349/4), //2 
952 
// FIXHR(5.73685662283492756461),

953 
}; 
954  
955 
/* 12 points IMDCT. We compute it "by hand" by factorizing obvious

956 
cases. */

957 
static void imdct12(int *out, int *in) 
958 
{ 
959 
int in0, in1, in2, in3, in4, in5, t1, t2;

960  
961 
in0= in[0*3]; 
962 
in1= in[1*3] + in[0*3]; 
963 
in2= in[2*3] + in[1*3]; 
964 
in3= in[3*3] + in[2*3]; 
965 
in4= in[4*3] + in[3*3]; 
966 
in5= in[5*3] + in[4*3]; 
967 
in5 += in3; 
968 
in3 += in1; 
969  
970 
in2= MULH(2*in2, C3);

971 
in3= MULH(4*in3, C3);

972  
973 
t1 = in0  in4; 
974 
t2 = MULH(2*(in1  in5), icos36h[4]); 
975  
976 
out[ 7]=

977 
out[10]= t1 + t2;

978 
out[ 1]=

979 
out[ 4]= t1  t2;

980  
981 
in0 += in4>>1;

982 
in4 = in0 + in2; 
983 
in5 += 2*in1;

984 
in1 = MULH(in5 + in3, icos36h[1]);

985 
out[ 8]=

986 
out[ 9]= in4 + in1;

987 
out[ 2]=

988 
out[ 3]= in4  in1;

989  
990 
in0 = in2; 
991 
in5 = MULH(2*(in5  in3), icos36h[7]); 
992 
out[ 0]=

993 
out[ 5]= in0  in5;

994 
out[ 6]=

995 
out[11]= in0 + in5;

996 
} 
997  
998 
/* cos(pi*i/18) */

999 
#define C1 FIXHR(0.98480775301220805936/2) 
1000 
#define C2 FIXHR(0.93969262078590838405/2) 
1001 
#define C3 FIXHR(0.86602540378443864676/2) 
1002 
#define C4 FIXHR(0.76604444311897803520/2) 
1003 
#define C5 FIXHR(0.64278760968653932632/2) 
1004 
#define C6 FIXHR(0.5/2) 
1005 
#define C7 FIXHR(0.34202014332566873304/2) 
1006 
#define C8 FIXHR(0.17364817766693034885/2) 
1007  
1008  
1009 
/* using Lee like decomposition followed by hand coded 9 points DCT */

1010 
static void imdct36(int *out, int *buf, int *in, int *win) 
1011 
{ 
1012 
int i, j, t0, t1, t2, t3, s0, s1, s2, s3;

1013 
int tmp[18], *tmp1, *in1; 
1014  
1015 
for(i=17;i>=1;i) 
1016 
in[i] += in[i1];

1017 
for(i=17;i>=3;i=2) 
1018 
in[i] += in[i2];

1019  
1020 
for(j=0;j<2;j++) { 
1021 
tmp1 = tmp + j; 
1022 
in1 = in + j; 
1023 
#if 0

1024 
//more accurate but slower

1025 
int64_t t0, t1, t2, t3;

1026 
t2 = in1[2*4] + in1[2*8]  in1[2*2];

1027 

1028 
t3 = (in1[2*0] + (int64_t)(in1[2*6]>>1))<<32;

1029 
t1 = in1[2*0]  in1[2*6];

1030 
tmp1[ 6] = t1  (t2>>1);

1031 
tmp1[16] = t1 + t2;

1032 

1033 
t0 = MUL64(2*(in1[2*2] + in1[2*4]), C2);

1034 
t1 = MUL64( in1[2*4]  in1[2*8] , 2*C8);

1035 
t2 = MUL64(2*(in1[2*2] + in1[2*8]), C4);

1036 

1037 
tmp1[10] = (t3  t0  t2) >> 32;

1038 
tmp1[ 2] = (t3 + t0 + t1) >> 32;

1039 
tmp1[14] = (t3 + t2  t1) >> 32;

1040 

1041 
tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7]  in1[2*1]), C3);

1042 
t2 = MUL64(2*(in1[2*1] + in1[2*5]), C1);

1043 
t3 = MUL64( in1[2*5]  in1[2*7] , 2*C7);

1044 
t0 = MUL64(2*in1[2*3], C3);

1045 

1046 
t1 = MUL64(2*(in1[2*1] + in1[2*7]), C5);

1047 

1048 
tmp1[ 0] = (t2 + t3 + t0) >> 32;

1049 
tmp1[12] = (t2 + t1  t0) >> 32;

1050 
tmp1[ 8] = (t3  t1  t0) >> 32;

1051 
#else

1052 
t2 = in1[2*4] + in1[2*8]  in1[2*2]; 
1053  
1054 
t3 = in1[2*0] + (in1[2*6]>>1); 
1055 
t1 = in1[2*0]  in1[2*6]; 
1056 
tmp1[ 6] = t1  (t2>>1); 
1057 
tmp1[16] = t1 + t2;

1058  
1059 
t0 = MULH(2*(in1[2*2] + in1[2*4]), C2); 
1060 
t1 = MULH( in1[2*4]  in1[2*8] , 2*C8); 
1061 
t2 = MULH(2*(in1[2*2] + in1[2*8]), C4); 
1062  
1063 
tmp1[10] = t3  t0  t2;

1064 
tmp1[ 2] = t3 + t0 + t1;

1065 
tmp1[14] = t3 + t2  t1;

1066  
1067 
tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7]  in1[2*1]), C3); 
1068 
t2 = MULH(2*(in1[2*1] + in1[2*5]), C1); 
1069 
t3 = MULH( in1[2*5]  in1[2*7] , 2*C7); 
1070 
t0 = MULH(2*in1[2*3], C3); 
1071  
1072 
t1 = MULH(2*(in1[2*1] + in1[2*7]), C5); 
1073  
1074 
tmp1[ 0] = t2 + t3 + t0;

1075 
tmp1[12] = t2 + t1  t0;

1076 
tmp1[ 8] = t3  t1  t0;

1077 
#endif

1078 
} 
1079  
1080 
i = 0;

1081 
for(j=0;j<4;j++) { 
1082 
t0 = tmp[i]; 
1083 
t1 = tmp[i + 2];

1084 
s0 = t1 + t0; 
1085 
s2 = t1  t0; 
1086  
1087 
t2 = tmp[i + 1];

1088 
t3 = tmp[i + 3];

1089 
s1 = MULH(2*(t3 + t2), icos36h[j]);

1090 
s3 = MULL(t3  t2, icos36[8  j], FRAC_BITS);

1091  
1092 
t0 = s0 + s1; 
1093 
t1 = s0  s1; 
1094 
out[(9 + j)*SBLIMIT] = MULH(t1, win[9 + j]) + buf[9 + j]; 
1095 
out[(8  j)*SBLIMIT] = MULH(t1, win[8  j]) + buf[8  j]; 
1096 
buf[9 + j] = MULH(t0, win[18 + 9 + j]); 
1097 
buf[8  j] = MULH(t0, win[18 + 8  j]); 
1098  
1099 
t0 = s2 + s3; 
1100 
t1 = s2  s3; 
1101 
out[(9 + 8  j)*SBLIMIT] = MULH(t1, win[9 + 8  j]) + buf[9 + 8  j]; 
1102 
out[( j)*SBLIMIT] = MULH(t1, win[ j]) + buf[ j]; 
1103 
buf[9 + 8  j] = MULH(t0, win[18 + 9 + 8  j]); 
1104 
buf[ + j] = MULH(t0, win[18 + j]);

1105 
i += 4;

1106 
} 
1107  
1108 
s0 = tmp[16];

1109 
s1 = MULH(2*tmp[17], icos36h[4]); 
1110 
t0 = s0 + s1; 
1111 
t1 = s0  s1; 
1112 
out[(9 + 4)*SBLIMIT] = MULH(t1, win[9 + 4]) + buf[9 + 4]; 
1113 
out[(8  4)*SBLIMIT] = MULH(t1, win[8  4]) + buf[8  4]; 
1114 
buf[9 + 4] = MULH(t0, win[18 + 9 + 4]); 
1115 
buf[8  4] = MULH(t0, win[18 + 8  4]); 
1116 
} 
1117  
1118 
/* return the number of decoded frames */

1119 
static int mp_decode_layer1(MPADecodeContext *s) 
1120 
{ 
1121 
int bound, i, v, n, ch, j, mant;

1122 
uint8_t allocation[MPA_MAX_CHANNELS][SBLIMIT]; 
1123 
uint8_t scale_factors[MPA_MAX_CHANNELS][SBLIMIT]; 
1124  
1125 
if (s>mode == MPA_JSTEREO)

1126 
bound = (s>mode_ext + 1) * 4; 
1127 
else

1128 
bound = SBLIMIT; 
1129  
1130 
/* allocation bits */

1131 
for(i=0;i<bound;i++) { 
1132 
for(ch=0;ch<s>nb_channels;ch++) { 
1133 
allocation[ch][i] = get_bits(&s>gb, 4);

1134 
} 
1135 
} 
1136 
for(i=bound;i<SBLIMIT;i++) {

1137 
allocation[0][i] = get_bits(&s>gb, 4); 
1138 
} 
1139  
1140 
/* scale factors */

1141 
for(i=0;i<bound;i++) { 
1142 
for(ch=0;ch<s>nb_channels;ch++) { 
1143 
if (allocation[ch][i])

1144 
scale_factors[ch][i] = get_bits(&s>gb, 6);

1145 
} 
1146 
} 
1147 
for(i=bound;i<SBLIMIT;i++) {

1148 
if (allocation[0][i]) { 
1149 
scale_factors[0][i] = get_bits(&s>gb, 6); 
1150 
scale_factors[1][i] = get_bits(&s>gb, 6); 
1151 
} 
1152 
} 
1153  
1154 
/* compute samples */

1155 
for(j=0;j<12;j++) { 
1156 
for(i=0;i<bound;i++) { 
1157 
for(ch=0;ch<s>nb_channels;ch++) { 
1158 
n = allocation[ch][i]; 
1159 
if (n) {

1160 
mant = get_bits(&s>gb, n + 1);

1161 
v = l1_unscale(n, mant, scale_factors[ch][i]); 
1162 
} else {

1163 
v = 0;

1164 
} 
1165 
s>sb_samples[ch][j][i] = v; 
1166 
} 
1167 
} 
1168 
for(i=bound;i<SBLIMIT;i++) {

1169 
n = allocation[0][i];

1170 
if (n) {

1171 
mant = get_bits(&s>gb, n + 1);

1172 
v = l1_unscale(n, mant, scale_factors[0][i]);

1173 
s>sb_samples[0][j][i] = v;

1174 
v = l1_unscale(n, mant, scale_factors[1][i]);

1175 
s>sb_samples[1][j][i] = v;

1176 
} else {

1177 
s>sb_samples[0][j][i] = 0; 
1178 
s>sb_samples[1][j][i] = 0; 
1179 
} 
1180 
} 
1181 
} 
1182 
return 12; 
1183 
} 
1184  
1185 
static int mp_decode_layer2(MPADecodeContext *s) 
1186 
{ 
1187 
int sblimit; /* number of used subbands */ 
1188 
const unsigned char *alloc_table; 
1189 
int table, bit_alloc_bits, i, j, ch, bound, v;

1190 
unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT]; 
1191 
unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT]; 
1192 
unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3], *sf; 
1193 
int scale, qindex, bits, steps, k, l, m, b;

1194  
1195 
/* select decoding table */

1196 
table = ff_mpa_l2_select_table(s>bit_rate / 1000, s>nb_channels,

1197 
s>sample_rate, s>lsf); 
1198 
sblimit = ff_mpa_sblimit_table[table]; 
1199 
alloc_table = ff_mpa_alloc_tables[table]; 
1200  
1201 
if (s>mode == MPA_JSTEREO)

1202 
bound = (s>mode_ext + 1) * 4; 
1203 
else

1204 
bound = sblimit; 
1205  
1206 
dprintf(s>avctx, "bound=%d sblimit=%d\n", bound, sblimit);

1207  
1208 
/* sanity check */

1209 
if( bound > sblimit ) bound = sblimit;

1210  
1211 
/* parse bit allocation */

1212 
j = 0;

1213 
for(i=0;i<bound;i++) { 
1214 
bit_alloc_bits = alloc_table[j]; 
1215 
for(ch=0;ch<s>nb_channels;ch++) { 
1216 
bit_alloc[ch][i] = get_bits(&s>gb, bit_alloc_bits); 
1217 
} 
1218 
j += 1 << bit_alloc_bits;

1219 
} 
1220 
for(i=bound;i<sblimit;i++) {

1221 
bit_alloc_bits = alloc_table[j]; 
1222 
v = get_bits(&s>gb, bit_alloc_bits); 
1223 
bit_alloc[0][i] = v;

1224 
bit_alloc[1][i] = v;

1225 
j += 1 << bit_alloc_bits;

1226 
} 
1227  
1228 
/* scale codes */

1229 
for(i=0;i<sblimit;i++) { 
1230 
for(ch=0;ch<s>nb_channels;ch++) { 
1231 
if (bit_alloc[ch][i])

1232 
scale_code[ch][i] = get_bits(&s>gb, 2);

1233 
} 
1234 
} 
1235  
1236 
/* scale factors */

1237 
for(i=0;i<sblimit;i++) { 
1238 
for(ch=0;ch<s>nb_channels;ch++) { 
1239 
if (bit_alloc[ch][i]) {

1240 
sf = scale_factors[ch][i]; 
1241 
switch(scale_code[ch][i]) {

1242 
default:

1243 
case 0: 
1244 
sf[0] = get_bits(&s>gb, 6); 
1245 
sf[1] = get_bits(&s>gb, 6); 
1246 
sf[2] = get_bits(&s>gb, 6); 
1247 
break;

1248 
case 2: 
1249 
sf[0] = get_bits(&s>gb, 6); 
1250 
sf[1] = sf[0]; 
1251 
sf[2] = sf[0]; 
1252 
break;

1253 
case 1: 
1254 
sf[0] = get_bits(&s>gb, 6); 
1255 
sf[2] = get_bits(&s>gb, 6); 
1256 
sf[1] = sf[0]; 
1257 
break;

1258 
case 3: 
1259 
sf[0] = get_bits(&s>gb, 6); 
1260 
sf[2] = get_bits(&s>gb, 6); 
1261 
sf[1] = sf[2]; 
1262 
break;

1263 
} 
1264 
} 
1265 
} 
1266 
} 
1267  
1268 
/* samples */

1269 
for(k=0;k<3;k++) { 
1270 
for(l=0;l<12;l+=3) { 
1271 
j = 0;

1272 
for(i=0;i<bound;i++) { 
1273 
bit_alloc_bits = alloc_table[j]; 
1274 
for(ch=0;ch<s>nb_channels;ch++) { 
1275 
b = bit_alloc[ch][i]; 
1276 
if (b) {

1277 
scale = scale_factors[ch][i][k]; 
1278 
qindex = alloc_table[j+b]; 
1279 
bits = ff_mpa_quant_bits[qindex]; 
1280 
if (bits < 0) { 
1281 
/* 3 values at the same time */

1282 
v = get_bits(&s>gb, bits); 
1283 
steps = ff_mpa_quant_steps[qindex]; 
1284 
s>sb_samples[ch][k * 12 + l + 0][i] = 
1285 
l2_unscale_group(steps, v % steps, scale); 
1286 
v = v / steps; 
1287 
s>sb_samples[ch][k * 12 + l + 1][i] = 
1288 
l2_unscale_group(steps, v % steps, scale); 
1289 
v = v / steps; 
1290 
s>sb_samples[ch][k * 12 + l + 2][i] = 
1291 
l2_unscale_group(steps, v, scale); 
1292 
} else {

1293 
for(m=0;m<3;m++) { 
1294 
v = get_bits(&s>gb, bits); 
1295 
v = l1_unscale(bits  1, v, scale);

1296 
s>sb_samples[ch][k * 12 + l + m][i] = v;

1297 
} 
1298 
} 
1299 
} else {

1300 
s>sb_samples[ch][k * 12 + l + 0][i] = 0; 
1301 
s>sb_samples[ch][k * 12 + l + 1][i] = 0; 
1302 
s>sb_samples[ch][k * 12 + l + 2][i] = 0; 
1303 
} 
1304 
} 
1305 
/* next subband in alloc table */

1306 
j += 1 << bit_alloc_bits;

1307 
} 
1308 
/* XXX: find a way to avoid this duplication of code */

1309 
for(i=bound;i<sblimit;i++) {

1310 
bit_alloc_bits = alloc_table[j]; 
1311 
b = bit_alloc[0][i];

1312 
if (b) {

1313 
int mant, scale0, scale1;

1314 
scale0 = scale_factors[0][i][k];

1315 
scale1 = scale_factors[1][i][k];

1316 
qindex = alloc_table[j+b]; 
1317 
bits = ff_mpa_quant_bits[qindex]; 
1318 
if (bits < 0) { 
1319 
/* 3 values at the same time */

1320 
v = get_bits(&s>gb, bits); 
1321 
steps = ff_mpa_quant_steps[qindex]; 
1322 
mant = v % steps; 
1323 
v = v / steps; 
1324 
s>sb_samples[0][k * 12 + l + 0][i] = 
1325 
l2_unscale_group(steps, mant, scale0); 
1326 
s>sb_samples[1][k * 12 + l + 0][i] = 
1327 
l2_unscale_group(steps, mant, scale1); 
1328 
mant = v % steps; 
1329 
v = v / steps; 
1330 
s>sb_samples[0][k * 12 + l + 1][i] = 
1331 
l2_unscale_group(steps, mant, scale0); 
1332 
s>sb_samples[1][k * 12 + l + 1][i] = 
1333 
l2_unscale_group(steps, mant, scale1); 
1334 
s>sb_samples[0][k * 12 + l + 2][i] = 
1335 
l2_unscale_group(steps, v, scale0); 
1336 
s>sb_samples[1][k * 12 + l + 2][i] = 
1337 
l2_unscale_group(steps, v, scale1); 
1338 
} else {

1339 
for(m=0;m<3;m++) { 
1340 
mant = get_bits(&s>gb, bits); 
1341 
s>sb_samples[0][k * 12 + l + m][i] = 
1342 
l1_unscale(bits  1, mant, scale0);

1343 
s>sb_samples[1][k * 12 + l + m][i] = 
1344 
l1_unscale(bits  1, mant, scale1);

1345 
} 
1346 
} 
1347 
} else {

1348 
s>sb_samples[0][k * 12 + l + 0][i] = 0; 
1349 
s>sb_samples[0][k * 12 + l + 1][i] = 0; 
1350 
s>sb_samples[0][k * 12 + l + 2][i] = 0; 
1351 
s>sb_samples[1][k * 12 + l + 0][i] = 0; 
1352 
s>sb_samples[1][k * 12 + l + 1][i] = 0; 
1353 
s>sb_samples[1][k * 12 + l + 2][i] = 0; 
1354 
} 
1355 
/* next subband in alloc table */

1356 
j += 1 << bit_alloc_bits;

1357 
} 
1358 
/* fill remaining samples to zero */

1359 
for(i=sblimit;i<SBLIMIT;i++) {

1360 
for(ch=0;ch<s>nb_channels;ch++) { 
1361 
s>sb_samples[ch][k * 12 + l + 0][i] = 0; 
1362 
s>sb_samples[ch][k * 12 + l + 1][i] = 0; 
1363 
s>sb_samples[ch][k * 12 + l + 2][i] = 0; 
1364 
} 
1365 
} 
1366 
} 
1367 
} 
1368 
return 3 * 12; 
1369 
} 
1370  
1371 
static inline void lsf_sf_expand(int *slen, 
1372 
int sf, int n1, int n2, int n3) 
1373 
{ 
1374 
if (n3) {

1375 
slen[3] = sf % n3;

1376 
sf /= n3; 
1377 
} else {

1378 
slen[3] = 0; 
1379 
} 
1380 
if (n2) {

1381 
slen[2] = sf % n2;

1382 
sf /= n2; 
1383 
} else {

1384 
slen[2] = 0; 
1385 
} 
1386 
slen[1] = sf % n1;

1387 
sf /= n1; 
1388 
slen[0] = sf;

1389 
} 
1390  
1391 
static void exponents_from_scale_factors(MPADecodeContext *s, 
1392 
GranuleDef *g, 
1393 
int16_t *exponents) 
1394 
{ 
1395 
const uint8_t *bstab, *pretab;

1396 
int len, i, j, k, l, v0, shift, gain, gains[3]; 
1397 
int16_t *exp_ptr; 
1398  
1399 
exp_ptr = exponents; 
1400 
gain = g>global_gain  210;

1401 
shift = g>scalefac_scale + 1;

1402  
1403 
bstab = band_size_long[s>sample_rate_index]; 
1404 
pretab = mpa_pretab[g>preflag]; 
1405 
for(i=0;i<g>long_end;i++) { 
1406 
v0 = gain  ((g>scale_factors[i] + pretab[i]) << shift) + 400;

1407 
len = bstab[i]; 
1408 
for(j=len;j>0;j) 
1409 
*exp_ptr++ = v0; 
1410 
} 
1411  
1412 
if (g>short_start < 13) { 
1413 
bstab = band_size_short[s>sample_rate_index]; 
1414 
gains[0] = gain  (g>subblock_gain[0] << 3); 
1415 
gains[1] = gain  (g>subblock_gain[1] << 3); 
1416 
gains[2] = gain  (g>subblock_gain[2] << 3); 
1417 
k = g>long_end; 
1418 
for(i=g>short_start;i<13;i++) { 
1419 
len = bstab[i]; 
1420 
for(l=0;l<3;l++) { 
1421 
v0 = gains[l]  (g>scale_factors[k++] << shift) + 400;

1422 
for(j=len;j>0;j) 
1423 
*exp_ptr++ = v0; 
1424 
} 
1425 
} 
1426 
} 
1427 
} 
1428  
1429 
/* handle n = 0 too */

1430 
static inline int get_bitsz(GetBitContext *s, int n) 
1431 
{ 
1432 
if (n == 0) 
1433 
return 0; 
1434 
else

1435 
return get_bits(s, n);

1436 
} 
1437  
1438  
1439 
static void switch_buffer(MPADecodeContext *s, int *pos, int *end_pos, int *end_pos2){ 
1440 
if(s>in_gb.buffer && *pos >= s>gb.size_in_bits){

1441 
s>gb= s>in_gb; 
1442 
s>in_gb.buffer=NULL;

1443 
assert((get_bits_count(&s>gb) & 7) == 0); 
1444 
skip_bits_long(&s>gb, *pos  *end_pos); 
1445 
*end_pos2= 
1446 
*end_pos= *end_pos2 + get_bits_count(&s>gb)  *pos; 
1447 
*pos= get_bits_count(&s>gb); 
1448 
} 
1449 
} 
1450  
1451 
static int huffman_decode(MPADecodeContext *s, GranuleDef *g, 
1452 
int16_t *exponents, int end_pos2)

1453 
{ 
1454 
int s_index;

1455 
int i;

1456 
int last_pos, bits_left;

1457 
VLC *vlc; 
1458 
int end_pos= FFMIN(end_pos2, s>gb.size_in_bits);

1459  
1460 
/* low frequencies (called big values) */

1461 
s_index = 0;

1462 
for(i=0;i<3;i++) { 
1463 
int j, k, l, linbits;

1464 
j = g>region_size[i]; 
1465 
if (j == 0) 
1466 
continue;

1467 
/* select vlc table */

1468 
k = g>table_select[i]; 
1469 
l = mpa_huff_data[k][0];

1470 
linbits = mpa_huff_data[k][1];

1471 
vlc = &huff_vlc[l]; 
1472  
1473 
if(!l){

1474 
memset(&g>sb_hybrid[s_index], 0, sizeof(*g>sb_hybrid)*2*j); 
1475 
s_index += 2*j;

1476 
continue;

1477 
} 
1478  
1479 
/* read huffcode and compute each couple */

1480 
for(;j>0;j) { 
1481 
int exponent, x, y, v;

1482 
int pos= get_bits_count(&s>gb);

1483  
1484 
if (pos >= end_pos){

1485 
// av_log(NULL, AV_LOG_ERROR, "pos: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);

1486 
switch_buffer(s, &pos, &end_pos, &end_pos2); 
1487 
// av_log(NULL, AV_LOG_ERROR, "new pos: %d %d\n", pos, end_pos);

1488 
if(pos >= end_pos)

1489 
break;

1490 
} 
1491 
y = get_vlc2(&s>gb, vlc>table, 7, 3); 
1492  
1493 
if(!y){

1494 
g>sb_hybrid[s_index ] = 
1495 
g>sb_hybrid[s_index+1] = 0; 
1496 
s_index += 2;

1497 
continue;

1498 
} 
1499  
1500 
exponent= exponents[s_index]; 
1501  
1502 
dprintf(s>avctx, "region=%d n=%d x=%d y=%d exp=%d\n",

1503 
i, g>region_size[i]  j, x, y, exponent); 
1504 
if(y&16){ 
1505 
x = y >> 5;

1506 
y = y & 0x0f;

1507 
if (x < 15){ 
1508 
v = expval_table[ exponent ][ x ]; 
1509 
// v = expval_table[ (exponent&3) ][ x ] >> FFMIN(0  (exponent>>2), 31);

1510 
}else{

1511 
x += get_bitsz(&s>gb, linbits); 
1512 
v = l3_unscale(x, exponent); 
1513 
} 
1514 
if (get_bits1(&s>gb))

1515 
v = v; 
1516 
g>sb_hybrid[s_index] = v; 
1517 
if (y < 15){ 
1518 
v = expval_table[ exponent ][ y ]; 
1519 
}else{

1520 
y += get_bitsz(&s>gb, linbits); 
1521 
v = l3_unscale(y, exponent); 
1522 
} 
1523 
if (get_bits1(&s>gb))

1524 
v = v; 
1525 
g>sb_hybrid[s_index+1] = v;

1526 
}else{

1527 
x = y >> 5;

1528 
y = y & 0x0f;

1529 
x += y; 
1530 
if (x < 15){ 
1531 
v = expval_table[ exponent ][ x ]; 
1532 
}else{

1533 
x += get_bitsz(&s>gb, linbits); 
1534 
v = l3_unscale(x, exponent); 
1535 
} 
1536 
if (get_bits1(&s>gb))

1537 
v = v; 
1538 
g>sb_hybrid[s_index+!!y] = v; 
1539 
g>sb_hybrid[s_index+ !y] = 0;

1540 
} 
1541 
s_index+=2;

1542 
} 
1543 
} 
1544  
1545 
/* high frequencies */

1546 
vlc = &huff_quad_vlc[g>count1table_select]; 
1547 
last_pos=0;

1548 
while (s_index <= 572) { 
1549 
int pos, code;

1550 
pos = get_bits_count(&s>gb); 
1551 
if (pos >= end_pos) {

1552 
if (pos > end_pos2 && last_pos){

1553 
/* some encoders generate an incorrect size for this

1554 
part. We must go back into the data */

1555 
s_index = 4;

1556 
skip_bits_long(&s>gb, last_pos  pos); 
1557 
av_log(s>avctx, AV_LOG_INFO, "overread, skip %d enddists: %d %d\n", last_pos  pos, end_pospos, end_pos2pos);

1558 
if(s>error_recognition >= FF_ER_COMPLIANT)

1559 
s_index=0;

1560 
break;

1561 
} 
1562 
// av_log(NULL, AV_LOG_ERROR, "pos2: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);

1563 
switch_buffer(s, &pos, &end_pos, &end_pos2); 
1564 
// av_log(NULL, AV_LOG_ERROR, "new pos2: %d %d %d\n", pos, end_pos, s_index);

1565 
if(pos >= end_pos)

1566 
break;

1567 
} 
1568 
last_pos= pos; 
1569  
1570 
code = get_vlc2(&s>gb, vlc>table, vlc>bits, 1);

1571 
dprintf(s>avctx, "t=%d code=%d\n", g>count1table_select, code);

1572 
g>sb_hybrid[s_index+0]=

1573 
g>sb_hybrid[s_index+1]=

1574 
g>sb_hybrid[s_index+2]=

1575 
g>sb_hybrid[s_index+3]= 0; 
1576 
while(code){

1577 
static const int idxtab[16]={3,3,2,2,1,1,1,1,0,0,0,0,0,0,0,0}; 
1578 
int v;

1579 
int pos= s_index+idxtab[code];

1580 
code ^= 8>>idxtab[code];

1581 
v = exp_table[ exponents[pos] ]; 
1582 
// v = exp_table[ (exponents[pos]&3) ] >> FFMIN(0  (exponents[pos]>>2), 31);

1583 
if(get_bits1(&s>gb))

1584 
v = v; 
1585 
g>sb_hybrid[pos] = v; 
1586 
} 
1587 
s_index+=4;

1588 
} 
1589 
/* skip extension bits */

1590 
bits_left = end_pos2  get_bits_count(&s>gb); 
1591 
//av_log(NULL, AV_LOG_ERROR, "left:%d buf:%p\n", bits_left, s>in_gb.buffer);

1592 
if (bits_left < 0 && s>error_recognition >= FF_ER_COMPLIANT) { 
1593 
av_log(s>avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);

1594 
s_index=0;

1595 
}else if(bits_left > 0 && s>error_recognition >= FF_ER_AGGRESSIVE){ 
1596 
av_log(s>avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);

1597 
s_index=0;

1598 
} 
1599 
memset(&g>sb_hybrid[s_index], 0, sizeof(*g>sb_hybrid)*(576  s_index)); 
1600 
skip_bits_long(&s>gb, bits_left); 
1601  
1602 
i= get_bits_count(&s>gb); 
1603 
switch_buffer(s, &i, &end_pos, &end_pos2); 
1604  
1605 
return 0; 
1606 
} 
1607  
1608 
/* Reorder short blocks from bitstream order to interleaved order. It

1609 
would be faster to do it in parsing, but the code would be far more

1610 
complicated */

1611 
static void reorder_block(MPADecodeContext *s, GranuleDef *g) 
1612 
{ 
1613 
int i, j, len;

1614 
int32_t *ptr, *dst, *ptr1; 
1615 
int32_t tmp[576];

1616  
1617 
if (g>block_type != 2) 
1618 
return;

1619  
1620 
if (g>switch_point) {

1621 
if (s>sample_rate_index != 8) { 
1622 
ptr = g>sb_hybrid + 36;

1623 
} else {

1624 
ptr = g>sb_hybrid + 48;

1625 
} 
1626 
} else {

1627 
ptr = g>sb_hybrid; 
1628 
} 
1629  
1630 
for(i=g>short_start;i<13;i++) { 
1631 
len = band_size_short[s>sample_rate_index][i]; 
1632 
ptr1 = ptr; 
1633 
dst = tmp; 
1634 
for(j=len;j>0;j) { 
1635 
*dst++ = ptr[0*len];

1636 
*dst++ = ptr[1*len];

1637 
*dst++ = ptr[2*len];

1638 
ptr++; 
1639 
} 
1640 
ptr+=2*len;

1641 
memcpy(ptr1, tmp, len * 3 * sizeof(*ptr1)); 
1642 
} 
1643 
} 
1644  
1645 
#define ISQRT2 FIXR(0.70710678118654752440) 
1646  
1647 
static void compute_stereo(MPADecodeContext *s, 
1648 
GranuleDef *g0, GranuleDef *g1) 
1649 
{ 
1650 
int i, j, k, l;

1651 
int32_t v1, v2; 
1652 
int sf_max, tmp0, tmp1, sf, len, non_zero_found;

1653 
int32_t (*is_tab)[16];

1654 
int32_t *tab0, *tab1; 
1655 
int non_zero_found_short[3]; 
1656  
1657 
/* intensity stereo */

1658 
if (s>mode_ext & MODE_EXT_I_STEREO) {

1659 
if (!s>lsf) {

1660 
is_tab = is_table; 
1661 
sf_max = 7;

1662 
} else {

1663 
is_tab = is_table_lsf[g1>scalefac_compress & 1];

1664 
sf_max = 16;

1665 
} 
1666  
1667 
tab0 = g0>sb_hybrid + 576;

1668 
tab1 = g1>sb_hybrid + 576;

1669  
1670 
non_zero_found_short[0] = 0; 
1671 
non_zero_found_short[1] = 0; 
1672 
non_zero_found_short[2] = 0; 
1673 
k = (13  g1>short_start) * 3 + g1>long_end  3; 
1674 
for(i = 12;i >= g1>short_start;i) { 
1675 
/* for last band, use previous scale factor */

1676 
if (i != 11) 
1677 
k = 3;

1678 
len = band_size_short[s>sample_rate_index][i]; 
1679 
for(l=2;l>=0;l) { 
1680 
tab0 = len; 
1681 
tab1 = len; 
1682 
if (!non_zero_found_short[l]) {

1683 
/* test if non zero band. if so, stop doing istereo */

1684 
for(j=0;j<len;j++) { 
1685 
if (tab1[j] != 0) { 
1686 
non_zero_found_short[l] = 1;

1687 
goto found1;

1688 
} 
1689 
} 
1690 
sf = g1>scale_factors[k + l]; 
1691 
if (sf >= sf_max)

1692 
goto found1;

1693  
1694 
v1 = is_tab[0][sf];

1695 
v2 = is_tab[1][sf];

1696 
for(j=0;j<len;j++) { 
1697 
tmp0 = tab0[j]; 
1698 
tab0[j] = MULL(tmp0, v1, FRAC_BITS); 
1699 
tab1[j] = MULL(tmp0, v2, FRAC_BITS); 
1700 
} 
1701 
} else {

1702 
found1:

1703 
if (s>mode_ext & MODE_EXT_MS_STEREO) {

1704 
/* lower part of the spectrum : do ms stereo

1705 
if enabled */

1706 
for(j=0;j<len;j++) { 
1707 
tmp0 = tab0[j]; 
1708 
tmp1 = tab1[j]; 
1709 
tab0[j] = MULL(tmp0 + tmp1, ISQRT2, FRAC_BITS); 
1710 
tab1[j] = MULL(tmp0  tmp1, ISQRT2, FRAC_BITS); 
1711 
} 
1712 
} 
1713 
} 
1714 
} 
1715 
} 
1716  
1717 
non_zero_found = non_zero_found_short[0] 

1718 
non_zero_found_short[1] 

1719 
non_zero_found_short[2];

1720  
1721 
for(i = g1>long_end  1;i >= 0;i) { 
1722 
len = band_size_long[s>sample_rate_index][i]; 
1723 
tab0 = len; 
1724 
tab1 = len; 
1725 
/* test if non zero band. if so, stop doing istereo */

1726 
if (!non_zero_found) {

1727 
for(j=0;j<len;j++) { 
1728 
if (tab1[j] != 0) { 
1729 
non_zero_found = 1;

1730 
goto found2;

1731 
} 
1732 
} 
1733 
/* for last band, use previous scale factor */

1734 
k = (i == 21) ? 20 : i; 
1735 
sf = g1>scale_factors[k]; 
1736 
if (sf >= sf_max)

1737 
goto found2;

1738 
v1 = is_tab[0][sf];

1739 
v2 = is_tab[1][sf];

1740 
for(j=0;j<len;j++) { 
1741 
tmp0 = tab0[j]; 
1742 
tab0[j] = MULL(tmp0, v1, FRAC_BITS); 
1743 
tab1[j] = MULL(tmp0, v2, FRAC_BITS); 
1744 
} 
1745 
} else {

1746 
found2:

1747 
if (s>mode_ext & MODE_EXT_MS_STEREO) {

1748 
/* lower part of the spectrum : do ms stereo

1749 
if enabled */

1750 
for(j=0;j<len;j++) { 
1751 
tmp0 = tab0[j]; 
1752 
tmp1 = tab1[j]; 
1753 
tab0[j] = MULL(tmp0 + tmp1, ISQRT2, FRAC_BITS); 
1754 
tab1[j] = MULL(tmp0  tmp1, ISQRT2, FRAC_BITS); 
1755 
} 
1756 
} 
1757 
} 
1758 
} 
1759 
} else if (s>mode_ext & MODE_EXT_MS_STEREO) { 
1760 
/* ms stereo ONLY */

1761 
/* NOTE: the 1/sqrt(2) normalization factor is included in the

1762 
global gain */

1763 
tab0 = g0>sb_hybrid; 
1764 
tab1 = g1>sb_hybrid; 
1765 
for(i=0;i<576;i++) { 
1766 
tmp0 = tab0[i]; 
1767 
tmp1 = tab1[i]; 
1768 
tab0[i] = tmp0 + tmp1; 
1769 
tab1[i] = tmp0  tmp1; 
1770 
} 
1771 
} 
1772 
} 
1773  
1774 
static void compute_antialias_integer(MPADecodeContext *s, 
1775 
GranuleDef *g) 
1776 
{ 
1777 
int32_t *ptr, *csa; 
1778 
int n, i;

1779  
1780 
/* we antialias only "long" bands */

1781 
if (g>block_type == 2) { 
1782 
if (!g>switch_point)

1783 
return;

1784 
/* XXX: check this for 8000Hz case */

1785 
n = 1;

1786 
} else {

1787 
n = SBLIMIT  1;

1788 
} 
1789  
1790 
ptr = g>sb_hybrid + 18;

1791 
for(i = n;i > 0;i) { 
1792 
int tmp0, tmp1, tmp2;

1793 
csa = &csa_table[0][0]; 
1794 
#define INT_AA(j) \

1795 
tmp0 = ptr[1j];\

1796 
tmp1 = ptr[ j];\ 
1797 
tmp2= MULH(tmp0 + tmp1, csa[0+4*j]);\ 
1798 
ptr[1j] = 4*(tmp2  MULH(tmp1, csa[2+4*j]));\ 
1799 
ptr[ j] = 4*(tmp2 + MULH(tmp0, csa[3+4*j])); 
1800  
1801 
INT_AA(0)

1802 
INT_AA(1)

1803 
INT_AA(2)

1804 
INT_AA(3)

1805 
INT_AA(4)

1806 
INT_AA(5)

1807 
INT_AA(6)

1808 
INT_AA(7)

1809  
1810 
ptr += 18;

1811 
} 
1812 
} 
1813  
1814 
static void compute_antialias_float(MPADecodeContext *s, 
1815 
GranuleDef *g) 
1816 
{ 
1817 
int32_t *ptr; 
1818 
int n, i;

1819  
1820 
/* we antialias only "long" bands */

1821 
if (g>block_type == 2) { 
1822 
if (!g>switch_point)

1823 
return;

1824 
/* XXX: check this for 8000Hz case */

1825 
n = 1;

1826 
} else {

1827 
n = SBLIMIT  1;

1828 
} 
1829  
1830 
ptr = g>sb_hybrid + 18;

1831 
for(i = n;i > 0;i) { 
1832 
float tmp0, tmp1;

1833 
float *csa = &csa_table_float[0][0]; 
1834 
#define FLOAT_AA(j)\

1835 
tmp0= ptr[1j];\

1836 
tmp1= ptr[ j];\ 
1837 
ptr[1j] = lrintf(tmp0 * csa[0+4*j]  tmp1 * csa[1+4*j]);\ 
1838 
ptr[ j] = lrintf(tmp0 * csa[1+4*j] + tmp1 * csa[0+4*j]); 
1839  
1840 
FLOAT_AA(0)

1841 
FLOAT_AA(1)

1842 
FLOAT_AA(2)

1843 
FLOAT_AA(3)

1844 
FLOAT_AA(4)

1845 
FLOAT_AA(5)

1846 
FLOAT_AA(6)

1847 
FLOAT_AA(7)

1848  
1849 
ptr += 18;

1850 
} 
1851 
} 
1852  
1853 
static void compute_imdct(MPADecodeContext *s, 
1854 
GranuleDef *g, 
1855 
int32_t *sb_samples, 
1856 
int32_t *mdct_buf) 
1857 
{ 
1858 
int32_t *ptr, *win, *win1, *buf, *out_ptr, *ptr1; 
1859 
int32_t out2[12];

1860 
int i, j, mdct_long_end, v, sblimit;

1861  
1862 
/* find last non zero block */

1863 
ptr = g>sb_hybrid + 576;

1864 
ptr1 = g>sb_hybrid + 2 * 18; 
1865 
while (ptr >= ptr1) {

1866 
ptr = 6;

1867 
v = ptr[0]  ptr[1]  ptr[2]  ptr[3]  ptr[4]  ptr[5]; 
1868 
if (v != 0) 
1869 
break;

1870 
} 
1871 
sblimit = ((ptr  g>sb_hybrid) / 18) + 1; 
1872  
1873 
if (g>block_type == 2) { 
1874 
/* XXX: check for 8000 Hz */

1875 
if (g>switch_point)

1876 
mdct_long_end = 2;

1877 
else

1878 
mdct_long_end = 0;

1879 
} else {

1880 
mdct_long_end = sblimit; 
1881 
} 
1882  
1883 
buf = mdct_buf; 
1884 
ptr = g>sb_hybrid; 
1885 
for(j=0;j<mdct_long_end;j++) { 
1886 
/* apply window & overlap with previous buffer */

1887 
out_ptr = sb_samples + j; 
1888 
/* select window */

1889 
if (g>switch_point && j < 2) 
1890 
win1 = mdct_win[0];

1891 
else

1892 
win1 = mdct_win[g>block_type]; 
1893 
/* select frequency inversion */

1894 
win = win1 + ((4 * 36) & (j & 1)); 
1895 
imdct36(out_ptr, buf, ptr, win); 
1896 
out_ptr += 18*SBLIMIT;

1897 
ptr += 18;

1898 
buf += 18;

1899 
} 
1900 
for(j=mdct_long_end;j<sblimit;j++) {

1901 
/* select frequency inversion */

1902 
win = mdct_win[2] + ((4 * 36) & (j & 1)); 
1903 
out_ptr = sb_samples + j; 
1904  
1905 
for(i=0; i<6; i++){ 
1906 
*out_ptr = buf[i]; 
1907 
out_ptr += SBLIMIT; 
1908 
} 
1909 
imdct12(out2, ptr + 0);

1910 
for(i=0;i<6;i++) { 
1911 
*out_ptr = MULH(out2[i], win[i]) + buf[i + 6*1]; 
1912 
buf[i + 6*2] = MULH(out2[i + 6], win[i + 6]); 
1913 
out_ptr += SBLIMIT; 
1914 
} 
1915 
imdct12(out2, ptr + 1);

1916 
for(i=0;i<6;i++) { 
1917 
*out_ptr = MULH(out2[i], win[i]) + buf[i + 6*2]; 
1918 
buf[i + 6*0] = MULH(out2[i + 6], win[i + 6]); 
1919 
out_ptr += SBLIMIT; 
1920 
} 
1921 
imdct12(out2, ptr + 2);

1922 
for(i=0;i<6;i++) { 
1923 
buf[i + 6*0] = MULH(out2[i], win[i]) + buf[i + 6*0]; 
1924 
buf[i + 6*1] = MULH(out2[i + 6], win[i + 6]); 
1925 
buf[i + 6*2] = 0; 
1926 
} 
1927 
ptr += 18;

1928 
buf += 18;

1929 
} 
1930 
/* zero bands */

1931 
for(j=sblimit;j<SBLIMIT;j++) {

1932 
/* overlap */

1933 
out_ptr = sb_samples + j; 
1934 
for(i=0;i<18;i++) { 
1935 
*out_ptr = buf[i]; 
1936 
buf[i] = 0;

1937 
out_ptr += SBLIMIT; 
1938 
} 
1939 
buf += 18;

1940 
} 
1941 
} 
1942  
1943 
/* main layer3 decoding function */

1944 
static int mp_decode_layer3(MPADecodeContext *s) 
1945 
{ 
1946 
int nb_granules, main_data_begin, private_bits;

1947 
int gr, ch, blocksplit_flag, i, j, k, n, bits_pos;

1948 
GranuleDef granules[2][2], *g; 
1949 
int16_t exponents[576];

1950  
1951 
/* read side info */

1952 
if (s>lsf) {

1953 
main_data_begin = get_bits(&s>gb, 8);

1954 
private_bits = get_bits(&s>gb, s>nb_channels); 
1955 
nb_granules = 1;

1956 
} else {

1957 
main_data_begin = get_bits(&s>gb, 9);

1958 
if (s>nb_channels == 2) 
1959 
private_bits = get_bits(&s>gb, 3);

1960 
else

1961 
private_bits = get_bits(&s>gb, 5);

1962 
nb_granules = 2;

1963 
for(ch=0;ch<s>nb_channels;ch++) { 
1964 
granules[ch][0].scfsi = 0; /* all scale factors are transmitted */ 
1965 
granules[ch][1].scfsi = get_bits(&s>gb, 4); 
1966 
} 
1967 
} 
1968  
1969 
for(gr=0;gr<nb_granules;gr++) { 
1970 
for(ch=0;ch<s>nb_channels;ch++) { 
1971 
dprintf(s>avctx, "gr=%d ch=%d: side_info\n", gr, ch);

1972 
g = &granules[ch][gr]; 
1973 
g>part2_3_length = get_bits(&s>gb, 12);

1974 
g>big_values = get_bits(&s>gb, 9);

1975 
if(g>big_values > 288){ 
1976 
av_log(s>avctx, AV_LOG_ERROR, "big_values too big\n");

1977 
return 1; 
1978 
} 
1979  
1980 
g>global_gain = get_bits(&s>gb, 8);

1981 
/* if MS stereo only is selected, we precompute the

1982 
1/sqrt(2) renormalization factor */

1983 
if ((s>mode_ext & (MODE_EXT_MS_STEREO  MODE_EXT_I_STEREO)) ==

1984 
MODE_EXT_MS_STEREO) 
1985 
g>global_gain = 2;

1986 
if (s>lsf)

1987 
g>scalefac_compress = get_bits(&s>gb, 9);

1988 
else

1989 
g>scalefac_compress = get_bits(&s>gb, 4);

1990 
blocksplit_flag = get_bits1(&s>gb); 
1991 
if (blocksplit_flag) {

1992 
g>block_type = get_bits(&s>gb, 2);

1993 
if (g>block_type == 0){ 
1994 
av_log(s>avctx, AV_LOG_ERROR, "invalid block type\n");

1995 
return 1; 
1996 
} 
1997 
g>switch_point = get_bits1(&s>gb); 
1998 
for(i=0;i<2;i++) 
1999 
g>table_select[i] = get_bits(&s>gb, 5);

2000 
for(i=0;i<3;i++) 
2001 
g>subblock_gain[i] = get_bits(&s>gb, 3);

2002 
ff_init_short_region(s, g); 
2003 
} else {

2004 
int region_address1, region_address2;

2005 
g>block_type = 0;

2006 
g>switch_point = 0;

2007 
for(i=0;i<3;i++) 
2008 
g>table_select[i] = get_bits(&s>gb, 5);

2009 
/* compute huffman coded region sizes */

2010 
region_address1 = get_bits(&s>gb, 4);

2011 
region_address2 = get_bits(&s>gb, 3);

2012 
dprintf(s>avctx, "region1=%d region2=%d\n",

2013 
region_address1, region_address2); 
2014 
ff_init_long_region(s, g, region_address1, region_address2); 
2015 
} 
2016 
ff_region_offset2size(g); 
2017 
ff_compute_band_indexes(s, g); 
2018  
2019 
g>preflag = 0;

2020 
if (!s>lsf)

2021 
g>preflag = get_bits1(&s>gb); 
2022 
g>scalefac_scale = get_bits1(&s>gb); 
2023 
g>count1table_select = get_bits1(&s>gb); 
2024 
dprintf(s>avctx, "block_type=%d switch_point=%d\n",

2025 
g>block_type, g>switch_point); 
2026 
} 
2027 
} 
2028  
2029 
if (!s>adu_mode) {

2030 
const uint8_t *ptr = s>gb.buffer + (get_bits_count(&s>gb)>>3); 
2031 
assert((get_bits_count(&s>gb) & 7) == 0); 
2032 
/* now we get bits from the main_data_begin offset */

2033 
dprintf(s>avctx, "seekback: %d\n", main_data_begin);

2034 
//av_log(NULL, AV_LOG_ERROR, "backstep:%d, lastbuf:%d\n", main_data_begin, s>last_buf_size);

2035  
2036 
memcpy(s>last_buf + s>last_buf_size, ptr, EXTRABYTES); 
2037 
s>in_gb= s>gb; 
2038 
init_get_bits(&s>gb, s>last_buf, s>last_buf_size*8);

2039 
skip_bits_long(&s>gb, 8*(s>last_buf_size  main_data_begin));

2040 
} 
2041  
2042 
for(gr=0;gr<nb_granules;gr++) { 
2043 
for(ch=0;ch<s>nb_channels;ch++) { 
2044 
g = &granules[ch][gr]; 
2045 
if(get_bits_count(&s>gb)<0){ 
2046 
av_log(s>avctx, AV_LOG_ERROR, "mdb:%d, lastbuf:%d skipping granule %d\n",

2047 
main_data_begin, s>last_buf_size, gr); 
2048 
skip_bits_long(&s>gb, g>part2_3_length); 
2049 
memset(g>sb_hybrid, 0, sizeof(g>sb_hybrid)); 
2050 
if(get_bits_count(&s>gb) >= s>gb.size_in_bits && s>in_gb.buffer){

2051 
skip_bits_long(&s>in_gb, get_bits_count(&s>gb)  s>gb.size_in_bits); 
2052 
s>gb= s>in_gb; 
2053 
s>in_gb.buffer=NULL;

2054 
} 
2055 
continue;

2056 
} 
2057  
2058 
bits_pos = get_bits_count(&s>gb); 
2059  
2060 
if (!s>lsf) {

2061 
uint8_t *sc; 
2062 
int slen, slen1, slen2;

2063  
2064 
/* MPEG1 scale factors */

2065 
slen1 = slen_table[0][g>scalefac_compress];

2066 
slen2 = slen_table[1][g>scalefac_compress];

2067 
dprintf(s>avctx, "slen1=%d slen2=%d\n", slen1, slen2);

2068 
if (g>block_type == 2) { 
2069 
n = g>switch_point ? 17 : 18; 
2070 
j = 0;

2071 
if(slen1){

2072 
for(i=0;i<n;i++) 
2073 
g>scale_factors[j++] = get_bits(&s>gb, slen1); 
2074 
}else{

2075 
for(i=0;i<n;i++) 
2076 
g>scale_factors[j++] = 0;

2077 
} 
2078 
if(slen2){

2079 
for(i=0;i<18;i++) 
2080 
g>scale_factors[j++] = get_bits(&s>gb, slen2); 
2081 
for(i=0;i<3;i++) 
2082 
g>scale_factors[j++] = 0;

2083 
}else{

2084 
for(i=0;i<21;i++) 
2085 
g>scale_factors[j++] = 0;

2086 
} 
2087 
} else {

2088 
sc = granules[ch][0].scale_factors;

2089 
j = 0;

2090 
for(k=0;k<4;k++) { 
2091 
n = (k == 0 ? 6 : 5); 
2092 
if ((g>scfsi & (0x8 >> k)) == 0) { 
2093 
slen = (k < 2) ? slen1 : slen2;

2094 
if(slen){

2095 
for(i=0;i<n;i++) 
2096 
g>scale_factors[j++] = get_bits(&s>gb, slen); 
2097 
}else{

2098 
for(i=0;i<n;i++) 
2099 
g>scale_factors[j++] = 0;

2100 
} 
2101 
} else {

2102 
/* simply copy from last granule */

2103 
for(i=0;i<n;i++) { 
2104 
g>scale_factors[j] = sc[j]; 
2105 
j++; 
2106 
} 
2107 
} 
2108 
} 
2109 
g>scale_factors[j++] = 0;

2110 
} 
2111 
} else {

2112 
int tindex, tindex2, slen[4], sl, sf; 
2113  
2114 
/* LSF scale factors */

2115 
if (g>block_type == 2) { 
2116 
tindex = g>switch_point ? 2 : 1; 
2117 
} else {

2118 
tindex = 0;

2119 
} 
2120 
sf = g>scalefac_compress; 
2121 
if ((s>mode_ext & MODE_EXT_I_STEREO) && ch == 1) { 
2122 
/* intensity stereo case */

2123 
sf >>= 1;

2124 
if (sf < 180) { 
2125 
lsf_sf_expand(slen, sf, 6, 6, 0); 
2126 
tindex2 = 3;

2127 
} else if (sf < 244) { 
2128 
lsf_sf_expand(slen, sf  180, 4, 4, 0); 
2129 
tindex2 = 4;

2130 
} else {

2131 
lsf_sf_expand(slen, sf  244, 3, 0, 0); 
2132 
tindex2 = 5;

2133 
} 
2134 
} else {

2135 
/* normal case */

2136 
if (sf < 400) { 
2137 
lsf_sf_expand(slen, sf, 5, 4, 4); 
2138 
tindex2 = 0;

2139 
} else if (sf < 500) { 
2140 
lsf_sf_expand(slen, sf  400, 5, 4, 0); 
2141 
tindex2 = 1;

2142 
} else {

2143 
lsf_sf_expand(slen, sf  500, 3, 0, 0); 
2144 
tindex2 = 2;

2145 
g>preflag = 1;

2146 
} 
2147 
} 
2148  
2149 
j = 0;

2150 
for(k=0;k<4;k++) { 
2151 
n = lsf_nsf_table[tindex2][tindex][k]; 
2152 
sl = slen[k]; 
2153 
if(sl){

2154 
for(i=0;i<n;i++) 
2155 
g>scale_factors[j++] = get_bits(&s>gb, sl); 
2156 
}else{

2157 
for(i=0;i<n;i++) 
2158 
g>scale_factors[j++] = 0;

2159 
} 
2160 
} 
2161 
/* XXX: should compute exact size */

2162 
for(;j<40;j++) 
2163 
g>scale_factors[j] = 0;

2164 
} 
2165  
2166 
exponents_from_scale_factors(s, g, exponents); 
2167  
2168 
/* read Huffman coded residue */

2169 
huffman_decode(s, g, exponents, bits_pos + g>part2_3_length); 
2170 
} /* ch */

2171  
2172 
if (s>nb_channels == 2) 
2173 
compute_stereo(s, &granules[0][gr], &granules[1][gr]); 
2174  
2175 
for(ch=0;ch<s>nb_channels;ch++) { 
2176 
g = &granules[ch][gr]; 
2177  
2178 
reorder_block(s, g); 
2179 
s>compute_antialias(s, g); 
2180 
compute_imdct(s, g, &s>sb_samples[ch][18 * gr][0], s>mdct_buf[ch]); 
2181 
} 
2182 
} /* gr */

2183 
if(get_bits_count(&s>gb)<0) 
2184 
skip_bits_long(&s>gb, get_bits_count(&s>gb)); 
2185 
return nb_granules * 18; 
2186 
} 
2187  
2188 
static int mp_decode_frame(MPADecodeContext *s, 
2189 
OUT_INT *samples, const uint8_t *buf, int buf_size) 
2190 
{ 
2191 
int i, nb_frames, ch;

2192 
OUT_INT *samples_ptr; 
2193  
2194 
init_get_bits(&s>gb, buf + HEADER_SIZE, (buf_size  HEADER_SIZE)*8);

2195  
2196 
/* skip error protection field */

2197 
if (s>error_protection)

2198 
skip_bits(&s>gb, 16);

2199  
2200 
dprintf(s>avctx, "frame %d:\n", s>frame_count);

2201 
switch(s>layer) {

2202 
case 1: 
2203 
s>avctx>frame_size = 384;

2204 
nb_frames = mp_decode_layer1(s); 
2205 
break;

2206 
case 2: 
2207 
s>avctx>frame_size = 1152;

2208 
nb_frames = mp_decode_layer2(s); 
2209 
break;

2210 
case 3: 
2211 
s>avctx>frame_size = s>lsf ? 576 : 1152; 
2212 
default:

2213 
nb_frames = mp_decode_layer3(s); 
2214  
2215 
s>last_buf_size=0;

2216 
if(s>in_gb.buffer){

2217 
align_get_bits(&s>gb); 
2218 
i= (s>gb.size_in_bits  get_bits_count(&s>gb))>>3;

2219 
if(i >= 0 && i <= BACKSTEP_SIZE){ 
2220 
memmove(s>last_buf, s>gb.buffer + (get_bits_count(&s>gb)>>3), i);

2221 
s>last_buf_size=i; 
2222 
}else

2223 
av_log(s>avctx, AV_LOG_ERROR, "invalid old backstep %d\n", i);

2224 
s>gb= s>in_gb; 
2225 
s>in_gb.buffer= NULL;

2226 
} 
2227  
2228 
align_get_bits(&s>gb); 
2229 
assert((get_bits_count(&s>gb) & 7) == 0); 
2230 
i= (s>gb.size_in_bits  get_bits_count(&s>gb))>>3;

2231  
2232 
if(i<0  i > BACKSTEP_SIZE  nb_frames<0){ 
2233 
if(i<0) 
2234 
av_log(s>avctx, AV_LOG_ERROR, "invalid new backstep %d\n", i);

2235 
i= FFMIN(BACKSTEP_SIZE, buf_size  HEADER_SIZE); 
2236 
} 
2237 
assert(i <= buf_size  HEADER_SIZE && i>= 0);

2238 
memcpy(s>last_buf + s>last_buf_size, s>gb.buffer + buf_size  HEADER_SIZE  i, i); 
2239 
s>last_buf_size += i; 
2240  
2241 
break;

2242 
} 
2243  
2244 
/* apply the synthesis filter */

2245 
for(ch=0;ch<s>nb_channels;ch++) { 
2246 
samples_ptr = samples + ch; 
2247 
for(i=0;i<nb_frames;i++) { 
2248 
ff_mpa_synth_filter(s>synth_buf[ch], &(s>synth_buf_offset[ch]), 
2249 
window, &s>dither_state, 
2250 
samples_ptr, s>nb_channels, 
2251 
s>sb_samples[ch][i]); 
2252 
samples_ptr += 32 * s>nb_channels;

2253 
} 
2254 
} 
2255  
2256 
return nb_frames * 32 * sizeof(OUT_INT) * s>nb_channels; 
2257 
} 
2258  
2259 
static int decode_frame(AVCodecContext * avctx, 
2260 
void *data, int *data_size, 
2261 
AVPacket *avpkt) 
2262 
{ 
2263 
const uint8_t *buf = avpkt>data;

2264 
int buf_size = avpkt>size;

2265 
MPADecodeContext *s = avctx>priv_data; 
2266 
uint32_t header; 
2267 
int out_size;

2268 
OUT_INT *out_samples = data; 
2269  
2270 
retry:

2271 
if(buf_size < HEADER_SIZE)

2272 
return 1; 
2273  
2274 
header = AV_RB32(buf); 
2275 
if(ff_mpa_check_header(header) < 0){ 
2276 
buf++; 
2277 
// buf_size;

2278 
av_log(avctx, AV_LOG_ERROR, "Header missing skipping one byte.\n");

2279 
goto retry;

2280 
} 
2281  
2282 
if (ff_mpegaudio_decode_header((MPADecodeHeader *)s, header) == 1) { 
2283 
/* free format: prepare to compute frame size */

2284 
s>frame_size = 1;

2285 
return 1; 
2286 
} 
2287 
/* update codec info */

2288 
avctx>channels = s>nb_channels; 
2289 
avctx>bit_rate = s>bit_rate; 
2290 
avctx>sub_id = s>layer; 
2291  
2292 
if(s>frame_size<=0  s>frame_size > buf_size){ 
2293 
av_log(avctx, AV_LOG_ERROR, "incomplete frame\n");

2294 
return 1; 
2295 
}else if(s>frame_size < buf_size){ 
2296 
av_log(avctx, AV_LOG_ERROR, "incorrect frame size\n");

2297 
buf_size= s>frame_size; 
2298 
} 
2299  
2300 
out_size = mp_decode_frame(s, out_samples, buf, buf_size); 
2301 
if(out_size>=0){ 
2302 
*data_size = out_size; 
2303 
avctx>sample_rate = s>sample_rate; 
2304 
//FIXME maybe move the other codec info stuff from above here too

2305 
}else

2306 
av_log(avctx, AV_LOG_DEBUG, "Error while decoding MPEG audio frame.\n"); //FIXME return 1 / but also return the number of bytes consumed 
2307 
s>frame_size = 0;

2308 
return buf_size;

2309 
} 
2310  
2311 
static void flush(AVCodecContext *avctx){ 
2312 
MPADecodeContext *s = avctx>priv_data; 
2313 
memset(s>synth_buf, 0, sizeof(s>synth_buf)); 
2314 
s>last_buf_size= 0;

2315 
} 
2316  
2317 
#if CONFIG_MP3ADU_DECODER

2318 
static int decode_frame_adu(AVCodecContext * avctx, 
2319 
void *data, int *data_size, 
2320 
AVPacket *avpkt) 
2321 
{ 
2322 
const uint8_t *buf = avpkt>data;

2323 
int buf_size = avpkt>size;

2324 
MPADecodeContext *s = avctx>priv_data; 
2325 
uint32_t header; 
2326 
int len, out_size;

2327 
OUT_INT *out_samples = data; 
2328  
2329 
len = buf_size; 
2330  
2331 
// Discard too short frames

2332 
if (buf_size < HEADER_SIZE) {

2333 
*data_size = 0;

2334 
return buf_size;

2335 
} 
2336  
2337  
2338 
if (len > MPA_MAX_CODED_FRAME_SIZE)

2339 
len = MPA_MAX_CODED_FRAME_SIZE; 
2340  
2341 
// Get header and restore sync word

2342 
header = AV_RB32(buf)  0xffe00000;

2343  
2344 
if (ff_mpa_check_header(header) < 0) { // Bad header, discard frame 
2345 
*data_size = 0;

2346 
return buf_size;

2347 
} 
2348  
2349 
ff_mpegaudio_decode_header((MPADecodeHeader *)s, header); 
2350 
/* update codec info */

2351 
avctx>sample_rate = s>sample_rate; 
2352 
avctx>channels = s>nb_channels; 
2353 
avctx>bit_rate = s>bit_rate; 
2354 
avctx>sub_id = s>layer; 
2355  
2356 
s>frame_size = len; 
2357  
2358 
if (avctx>parse_only) {

2359 
out_size = buf_size; 
2360 
} else {

2361 
out_size = mp_decode_frame(s, out_samples, buf, buf_size); 
2362 
} 
2363  
2364 
*data_size = out_size; 
2365 
return buf_size;

2366 
} 
2367 
#endif /* CONFIG_MP3ADU_DECODER */ 
2368  
2369 
#if CONFIG_MP3ON4_DECODER

2370  
2371 
/**

2372 
* Context for MP3On4 decoder

2373 
*/

2374 
typedef struct MP3On4DecodeContext { 
2375 
int frames; ///< number of mp3 frames per block (number of mp3 decoder instances) 
2376 
int syncword; ///< syncword patch 
2377 
const uint8_t *coff; ///< channels offsets in output buffer 
2378 
MPADecodeContext *mp3decctx[5]; ///< MPADecodeContext for every decoder instance 
2379 
} MP3On4DecodeContext; 
2380  
2381 
#include "mpeg4audio.h" 
2382  
2383 
/* Next 3 arrays are indexed by channel config number (passed via codecdata) */

2384 
static const uint8_t mp3Frames[8] = {0,1,1,2,3,3,4,5}; /* number of mp3 decoder instances */ 
2385 
/* offsets into output buffer, assume output order is FL FR BL BR C LFE */

2386 
static const uint8_t chan_offset[8][5] = { 
2387 
{0},

2388 
{0}, // C 
2389 
{0}, // FLR 
2390 
{2,0}, // C FLR 
2391 
{2,0,3}, // C FLR BS 
2392 
{4,0,2}, // C FLR BLRS 
2393 
{4,0,2,5}, // C FLR BLRS LFE 
2394 
{4,0,2,6,5}, // C FLR BLRS BLR LFE 
2395 
}; 
2396  
2397  
2398 
static int decode_init_mp3on4(AVCodecContext * avctx) 
2399 
{ 
2400 
MP3On4DecodeContext *s = avctx>priv_data; 
2401 
MPEG4AudioConfig cfg; 
2402 
int i;

2403  
2404 
if ((avctx>extradata_size < 2)  (avctx>extradata == NULL)) { 
2405 
av_log(avctx, AV_LOG_ERROR, "Codec extradata missing or too short.\n");

2406 
return 1; 
2407 
} 
2408  
2409 
ff_mpeg4audio_get_config(&cfg, avctx>extradata, avctx>extradata_size); 
2410 
if (!cfg.chan_config  cfg.chan_config > 7) { 
2411 
av_log(avctx, AV_LOG_ERROR, "Invalid channel config number.\n");

2412 
return 1; 
2413 
} 
2414 
s>frames = mp3Frames[cfg.chan_config]; 
2415 
s>coff = chan_offset[cfg.chan_config]; 
2416 
avctx>channels = ff_mpeg4audio_channels[cfg.chan_config]; 
2417  
2418 
if (cfg.sample_rate < 16000) 
2419 
s>syncword = 0xffe00000;

2420 
else

2421 
s>syncword = 0xfff00000;

2422  
2423 
/* Init the first mp3 decoder in standard way, so that all tables get builded

2424 
* We replace avctx>priv_data with the context of the first decoder so that

2425 
* decode_init() does not have to be changed.

2426 
* Other decoders will be initialized here copying data from the first context

2427 
*/

2428 
// Allocate zeroed memory for the first decoder context

2429 
s>mp3decctx[0] = av_mallocz(sizeof(MPADecodeContext)); 
2430 
// Put decoder context in place to make init_decode() happy

2431 
avctx>priv_data = s>mp3decctx[0];

2432 
decode_init(avctx); 
2433 
// Restore mp3on4 context pointer

2434 
avctx>priv_data = s; 
2435 
s>mp3decctx[0]>adu_mode = 1; // Set adu mode 
2436  
2437 
/* Create a separate codec/context for each frame (first is already ok).

2438 
* Each frame is 1 or 2 channels  up to 5 frames allowed

2439 
*/

2440 
for (i = 1; i < s>frames; i++) { 
2441 
s>mp3decctx[i] = av_mallocz(sizeof(MPADecodeContext));

2442 
s>mp3decctx[i]>compute_antialias = s>mp3decctx[0]>compute_antialias;

2443 
s>mp3decctx[i]>adu_mode = 1;

2444 
s>mp3decctx[i]>avctx = avctx; 
2445 
} 
2446  
2447 
return 0; 
2448 
} 
2449  
2450  
2451 
static av_cold int decode_close_mp3on4(AVCodecContext * avctx) 
2452 
{ 
2453 
MP3On4DecodeContext *s = avctx>priv_data; 
2454 
int i;

2455  
2456 
for (i = 0; i < s>frames; i++) 
2457 
if (s>mp3decctx[i])

2458 
av_free(s>mp3decctx[i]); 
2459  
2460 
return 0; 
2461 
} 
2462  
2463  
2464 
static int decode_frame_mp3on4(AVCodecContext * avctx, 
2465 
void *data, int *data_size, 
2466 
AVPacket *avpkt) 
2467 
{ 
2468 
const uint8_t *buf = avpkt>data;

2469 
int buf_size = avpkt>size;

2470 
MP3On4DecodeContext *s = avctx>priv_data; 
2471 
MPADecodeContext *m; 
2472 
int fsize, len = buf_size, out_size = 0; 
2473 
uint32_t header; 
2474 
OUT_INT *out_samples = data; 
2475 
OUT_INT decoded_buf[MPA_FRAME_SIZE * MPA_MAX_CHANNELS]; 
2476 
OUT_INT *outptr, *bp; 
2477 
int fr, j, n;

2478  
2479 
*data_size = 0;

2480 
// Discard too short frames

2481 
if (buf_size < HEADER_SIZE)

2482 
return 1; 
2483  
2484 
// If only one decoder interleave is not needed

2485 
outptr = s>frames == 1 ? out_samples : decoded_buf;

2486  
2487 
avctx>bit_rate = 0;

2488  
2489 
for (fr = 0; fr < s>frames; fr++) { 
2490 
fsize = AV_RB16(buf) >> 4;

2491 
fsize = FFMIN3(fsize, len, MPA_MAX_CODED_FRAME_SIZE); 
2492 
m = s>mp3decctx[fr]; 
2493 
assert (m != NULL);

2494  
2495 
header = (AV_RB32(buf) & 0x000fffff)  s>syncword; // patch header 
2496  
2497 
if (ff_mpa_check_header(header) < 0) // Bad header, discard block 
2498 
break;

2499  
2500 
ff_mpegaudio_decode_header((MPADecodeHeader *)m, header); 
2501 
out_size += mp_decode_frame(m, outptr, buf, fsize); 
2502 
buf += fsize; 
2503 
len = fsize; 
2504  
2505 
if(s>frames > 1) { 
2506 
n = m>avctx>frame_size*m>nb_channels; 
2507 
/* interleave output data */

2508 
bp = out_samples + s>coff[fr]; 
2509 
if(m>nb_channels == 1) { 
2510 
for(j = 0; j < n; j++) { 
2511 
*bp = decoded_buf[j]; 
2512 
bp += avctx>channels; 
2513 
} 
2514 
} else {

2515 
for(j = 0; j < n; j++) { 
2516 
bp[0] = decoded_buf[j++];

2517 
bp[1] = decoded_buf[j];

2518 
bp += avctx>channels; 
2519 
} 
2520 
} 
2521 
} 
2522 
avctx>bit_rate += m>bit_rate; 
2523 
} 
2524  
2525 
/* update codec info */

2526 
avctx>sample_rate = s>mp3decctx[0]>sample_rate;

2527  
2528 
*data_size = out_size; 
2529 
return buf_size;

2530 
} 
2531 
#endif /* CONFIG_MP3ON4_DECODER */ 
2532  
2533 
#if CONFIG_MP1_DECODER

2534 
AVCodec mp1_decoder = 
2535 
{ 
2536 
"mp1",

2537 
CODEC_TYPE_AUDIO, 
2538 
CODEC_ID_MP1, 
2539 
sizeof(MPADecodeContext),

2540 
decode_init, 
2541 
NULL,

2542 
NULL,

2543 
decode_frame, 
2544 
CODEC_CAP_PARSE_ONLY, 
2545 
.flush= flush, 
2546 
.long_name= NULL_IF_CONFIG_SMALL("MP1 (MPEG audio layer 1)"),

2547 
}; 
2548 
#endif

2549 
#if CONFIG_MP2_DECODER

2550 
AVCodec mp2_decoder = 
2551 
{ 
2552 
"mp2",

2553 
CODEC_TYPE_AUDIO, 
2554 
CODEC_ID_MP2, 
2555 
sizeof(MPADecodeContext),

2556 
decode_init, 
2557 
NULL,

2558 
NULL,

2559 
decode_frame, 
2560 
CODEC_CAP_PARSE_ONLY, 
2561 
.flush= flush, 
2562 
.long_name= NULL_IF_CONFIG_SMALL("MP2 (MPEG audio layer 2)"),

2563 
}; 
2564 
#endif

2565 
#if CONFIG_MP3_DECODER

2566 
AVCodec mp3_decoder = 
2567 
{ 
2568 
"mp3",

2569 
CODEC_TYPE_AUDIO, 
2570 
CODEC_ID_MP3, 
2571 
sizeof(MPADecodeContext),

2572 
decode_init, 
2573 
NULL,

2574 
NULL,

2575 
decode_frame, 
2576 
CODEC_CAP_PARSE_ONLY, 
2577 
.flush= flush, 
2578 
.long_name= NULL_IF_CONFIG_SMALL("MP3 (MPEG audio layer 3)"),

2579 
}; 
2580 
#endif

2581 
#if CONFIG_MP3ADU_DECODER

2582 
AVCodec mp3adu_decoder = 
2583 
{ 
2584 
"mp3adu",

2585 
CODEC_TYPE_AUDIO, 
2586 
CODEC_ID_MP3ADU, 
2587 
sizeof(MPADecodeContext),

2588 
decode_init, 
2589 
NULL,

2590 
NULL,

2591 
decode_frame_adu, 
2592 
CODEC_CAP_PARSE_ONLY, 
2593 
.flush= flush, 
2594 
.long_name= NULL_IF_CONFIG_SMALL("ADU (Application Data Unit) MP3 (MPEG audio layer 3)"),

2595 
}; 
2596 
#endif

2597 
#if CONFIG_MP3ON4_DECODER

2598 
AVCodec mp3on4_decoder = 
2599 
{ 
2600 
"mp3on4",

2601 
CODEC_TYPE_AUDIO, 
2602 
CODEC_ID_MP3ON4, 
2603 
sizeof(MP3On4DecodeContext),

2604 
decode_init_mp3on4, 
2605 
NULL,

2606 
decode_close_mp3on4, 
2607 
decode_frame_mp3on4, 
2608 
.flush= flush, 
2609 
.long_name= NULL_IF_CONFIG_SMALL("MP3onMP4"),

2610 
}; 
2611 
#endif
