FFmpeg: libavcodec/mpegaudiodec_template.c Source File

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mpegaudiodec_template.c

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1 /*

2 * MPEG Audio decoder

4 *

5 * This file is part of FFmpeg.

6 *

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

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

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

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

11 *

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

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

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

15 * Lesser General Public License for more details.

16 *

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

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

19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

20 */

22 /**

23 * @file

24 * MPEG Audio decoder

25 */

27 #include "libavutil/attributes.h"

28 #include "libavutil/avassert.h"

29 #include "libavutil/channel_layout.h"

30 #include "libavutil/float_dsp.h"

31 #include "libavutil/libm.h"

32 #include "avcodec.h"

33 #include "get_bits.h"

34 #include "internal.h"

35 #include "mathops.h"

36 #include "mpegaudiodsp.h"

38 /*

39 * TODO:

40 * - test lsf / mpeg25 extensively.

41 */

43 #include "mpegaudio.h"

44 #include "mpegaudiodecheader.h"

46 #define BACKSTEP_SIZE 512

47 #define EXTRABYTES 24

48 #define LAST_BUF_SIZE 2 * BACKSTEP_SIZE + EXTRABYTES

50 /* layer 3 "granule" */

51 typedef struct GranuleDef {

52 uint8_t scfsi;

53 int part2_3_length;

54 int big_values;

55 int global_gain;

56 int scalefac_compress;

57 uint8_t block_type;

58 uint8_t switch_point;

59 int table_select[3];

60 int subblock_gain[3];

61 uint8_t scalefac_scale;

62 uint8_t count1table_select;

63 int region_size[3]; /* number of huffman codes in each region */

64 int preflag;

65 int short_start, long_end; /* long/short band indexes */

66 uint8_t scale_factors[40];

67 DECLARE_ALIGNED(16, INTFLOAT, sb_hybrid)[SBLIMIT * 18]; /* 576 samples */

68 } GranuleDef;

70 typedef struct MPADecodeContext {

71 MPA_DECODE_HEADER

72 uint8_t last_buf[LAST_BUF_SIZE];

73 int last_buf_size;

74 /* next header (used in free format parsing) */

75 uint32_t free_format_next_header;

76 GetBitContext gb;

77 GetBitContext in_gb;

78 DECLARE_ALIGNED(32, MPA_INT, synth_buf)[MPA_MAX_CHANNELS][512 * 2];

79 int synth_buf_offset[MPA_MAX_CHANNELS];

80 DECLARE_ALIGNED(32, INTFLOAT, sb_samples)[MPA_MAX_CHANNELS][36][SBLIMIT];

81 INTFLOAT mdct_buf[MPA_MAX_CHANNELS][SBLIMIT * 18]; /* previous samples, for layer 3 MDCT */

82 GranuleDef granules[2][2]; /* Used in Layer 3 */

83 int adu_mode; ///< 0 for standard mp3, 1 for adu formatted mp3

84 int dither_state;

85 int err_recognition;

86 AVCodecContext* avctx;

87 MPADSPContext mpadsp;

88 AVFloatDSPContext *fdsp;

89 AVFrame *frame;

90 } MPADecodeContext;

92 #define HEADER_SIZE 4

94 #include "mpegaudiodata.h"

95 #include "mpegaudiodectab.h"

97 /* vlc structure for decoding layer 3 huffman tables */

98 static VLC huff_vlc[16];

99 static VLC_TYPE huff_vlc_tables[

100 0 + 128 + 128 + 128 + 130 + 128 + 154 + 166 +

101 142 + 204 + 190 + 170 + 542 + 460 + 662 + 414

102 ][2];

103 static const int huff_vlc_tables_sizes[16] = {

104 0, 128, 128, 128, 130, 128, 154, 166,

105 142, 204, 190, 170, 542, 460, 662, 414

106 };

107 static VLC huff_quad_vlc[2];

108 static VLC_TYPE huff_quad_vlc_tables[128+16][2];

109 static const int huff_quad_vlc_tables_sizes[2] = { 128, 16 };

110 /* computed from band_size_long */

111 static uint16_t band_index_long[9][23];

112 #include "mpegaudio_tablegen.h"

113 /* intensity stereo coef table */

114 static INTFLOAT is_table[2][16];

115 static INTFLOAT is_table_lsf[2][2][16];

116 static INTFLOAT csa_table[8][4];

117

118 static int16_t division_tab3[1<<6 ];

119 static int16_t division_tab5[1<<8 ];

120 static int16_t division_tab9[1<<11];

121

122 static int16_t * const division_tabs[4] = {

123 division_tab3, division_tab5, NULL, division_tab9

124 };

125

126 /* lower 2 bits: modulo 3, higher bits: shift */

127 static uint16_t scale_factor_modshift[64];

128 /* [i][j]: 2^(-j/3) * FRAC_ONE * 2^(i+2) / (2^(i+2) - 1) */

129 static int32_t scale_factor_mult[15][3];

130 /* mult table for layer 2 group quantization */

131

132 #define SCALE_GEN(v) \

133 { FIXR_OLD(1.0 * (v)), FIXR_OLD(0.7937005259 * (v)), FIXR_OLD(0.6299605249 * (v)) }

134

135 static const int32_t scale_factor_mult2[3][3] = {

136 SCALE_GEN(4.0 / 3.0), /* 3 steps */

137 SCALE_GEN(4.0 / 5.0), /* 5 steps */

138 SCALE_GEN(4.0 / 9.0), /* 9 steps */

139 };

140

141 /**

142 * Convert region offsets to region sizes and truncate

143 * size to big_values.

144 */

145 static void region_offset2size(GranuleDef *g)

146 {

147 int i, k, j = 0;

148 g->region_size[2] = 576 / 2;

149 for (i = 0; i < 3; i++) {

150 k = FFMIN(g->region_size[i], g->big_values);

151 g->region_size[i] = k - j;

152 j = k;

153 }

154 }

155

156 static void init_short_region(MPADecodeContext *s, GranuleDef *g)

157 {

158 if (g->block_type == 2) {

159 if (s->sample_rate_index != 8)

160 g->region_size[0] = (36 / 2);

161 else

162 g->region_size[0] = (72 / 2);

163 } else {

164 if (s->sample_rate_index <= 2)

165 g->region_size[0] = (36 / 2);

166 else if (s->sample_rate_index != 8)

167 g->region_size[0] = (54 / 2);

168 else

169 g->region_size[0] = (108 / 2);

170 }

171 g->region_size[1] = (576 / 2);

172 }

173

174 static void init_long_region(MPADecodeContext *s, GranuleDef *g,

175 int ra1, int ra2)

176 {

177 int l;

178 g->region_size[0] = band_index_long[s->sample_rate_index][ra1 + 1] >> 1;

179 /* should not overflow */

180 l = FFMIN(ra1 + ra2 + 2, 22);

181 g->region_size[1] = band_index_long[s->sample_rate_index][ l] >> 1;

182 }

183

184 static void compute_band_indexes(MPADecodeContext *s, GranuleDef *g)

185 {

186 if (g->block_type == 2) {

187 if (g->switch_point) {

188 if(s->sample_rate_index == 8)

189 avpriv_request_sample(s->avctx, "switch point in 8khz");

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

191 long blocks. For 8000Hz, we handle the 72 first

192 exponents as long blocks */

193 if (s->sample_rate_index <= 2)

194 g->long_end = 8;

195 else

196 g->long_end = 6;

197

198 g->short_start = 3;

199 } else {

200 g->long_end = 0;

201 g->short_start = 0;

202 }

203 } else {

204 g->short_start = 13;

205 g->long_end = 22;

206 }

207 }

208

209 /* layer 1 unscaling */

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

211 static inline int l1_unscale(int n, int mant, int scale_factor)

212 {

213 int shift, mod;

214 int64_t val;

215

216 shift = scale_factor_modshift[scale_factor];

217 mod = shift & 3;

218 shift >>= 2;

219 val = MUL64((int)(mant + (-1U << n) + 1), scale_factor_mult[n-1][mod]);

220 shift += n;

221 /* NOTE: at this point, 1 <= shift >= 21 + 15 */

222 return (int)((val + (1LL << (shift - 1))) >> shift);

223 }

224

225 static inline int l2_unscale_group(int steps, int mant, int scale_factor)

226 {

227 int shift, mod, val;

228

229 shift = scale_factor_modshift[scale_factor];

230 mod = shift & 3;

231 shift >>= 2;

232

233 val = (mant - (steps >> 1)) * scale_factor_mult2[steps >> 2][mod];

234 /* NOTE: at this point, 0 <= shift <= 21 */

235 if (shift > 0)

236 val = (val + (1 << (shift - 1))) >> shift;

237 return val;

238 }

239

240 /* compute value^(4/3) * 2^(exponent/4). It normalized to FRAC_BITS */

241 static inline int l3_unscale(int value, int exponent)

242 {

243 unsigned int m;

244 int e;

245

246 e = table_4_3_exp [4 * value + (exponent & 3)];

247 m = table_4_3_value[4 * value + (exponent & 3)];

248 e -= exponent >> 2;

249 #ifdef DEBUG

250 if(e < 1)

251 av_log(NULL, AV_LOG_WARNING, "l3_unscale: e is %d\n", e);

252 #endif

253 if (e > 31)

254 return 0;

255 m = (m + (1 << (e - 1))) >> e;

256

257 return m;

258 }

259

260 static av_cold void decode_init_static(void)

261 {

262 int i, j, k;

263 int offset;

264

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

266 for (i = 0; i < 64; i++) {

267 int shift, mod;

268 /* 1.0 (i = 3) is normalized to 2 ^ FRAC_BITS */

269 shift = i / 3;

270 mod = i % 3;

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

272 }

273

274 /* scale factor multiply for layer 1 */

275 for (i = 0; i < 15; i++) {

276 int n, norm;

277 n = i + 2;

278 norm = ((INT64_C(1) << n) * FRAC_ONE) / ((1 << n) - 1);

279 scale_factor_mult[i][0] = MULLx(norm, FIXR(1.0 * 2.0), FRAC_BITS);

280 scale_factor_mult[i][1] = MULLx(norm, FIXR(0.7937005259 * 2.0), FRAC_BITS);

281 scale_factor_mult[i][2] = MULLx(norm, FIXR(0.6299605249 * 2.0), FRAC_BITS);

282 av_dlog(NULL, "%d: norm=%x s=%x %x %x\n", i, norm,

283 scale_factor_mult[i][0],

284 scale_factor_mult[i][1],

285 scale_factor_mult[i][2]);

286 }

287

288 RENAME(ff_mpa_synth_init)(RENAME(ff_mpa_synth_window));

289

290 /* huffman decode tables */

291 offset = 0;

292 for (i = 1; i < 16; i++) {

293 const HuffTable *h = &mpa_huff_tables[i];

294 int xsize, x, y;

295 uint8_t tmp_bits [512] = { 0 };

296 uint16_t tmp_codes[512] = { 0 };

297

298 xsize = h->xsize;

299

300 j = 0;

301 for (x = 0; x < xsize; x++) {

302 for (y = 0; y < xsize; y++) {

303 tmp_bits [(x << 5) | y | ((x&&y)<<4)]= h->bits [j ];

304 tmp_codes[(x << 5) | y | ((x&&y)<<4)]= h->codes[j++];

305 }

306 }

307

308 /* XXX: fail test */

309 huff_vlc[i].table = huff_vlc_tables+offset;

310 huff_vlc[i].table_allocated = huff_vlc_tables_sizes[i];

311 init_vlc(&huff_vlc[i], 7, 512,

312 tmp_bits, 1, 1, tmp_codes, 2, 2,

313 INIT_VLC_USE_NEW_STATIC);

314 offset += huff_vlc_tables_sizes[i];

315 }

316 av_assert0(offset == FF_ARRAY_ELEMS(huff_vlc_tables));

317

318 offset = 0;

319 for (i = 0; i < 2; i++) {

320 huff_quad_vlc[i].table = huff_quad_vlc_tables+offset;

321 huff_quad_vlc[i].table_allocated = huff_quad_vlc_tables_sizes[i];

322 init_vlc(&huff_quad_vlc[i], i == 0 ? 7 : 4, 16,

323 mpa_quad_bits[i], 1, 1, mpa_quad_codes[i], 1, 1,

324 INIT_VLC_USE_NEW_STATIC);

325 offset += huff_quad_vlc_tables_sizes[i];

326 }

327 av_assert0(offset == FF_ARRAY_ELEMS(huff_quad_vlc_tables));

328

329 for (i = 0; i < 9; i++) {

330 k = 0;

331 for (j = 0; j < 22; j++) {

332 band_index_long[i][j] = k;

333 k += band_size_long[i][j];

334 }

335 band_index_long[i][22] = k;

336 }

337

338 /* compute n ^ (4/3) and store it in mantissa/exp format */

339

340 mpegaudio_tableinit();

341

342 for (i = 0; i < 4; i++) {

343 if (ff_mpa_quant_bits[i] < 0) {

344 for (j = 0; j < (1 << (-ff_mpa_quant_bits[i]+1)); j++) {

345 int val1, val2, val3, steps;

346 int val = j;

347 steps = ff_mpa_quant_steps[i];

348 val1 = val % steps;

349 val /= steps;

350 val2 = val % steps;

351 val3 = val / steps;

352 division_tabs[i][j] = val1 + (val2 << 4) + (val3 << 8);

353 }

354 }

355 }

356

357

358 for (i = 0; i < 7; i++) {

359 float f;

360 INTFLOAT v;

361 if (i != 6) {

362 f = tan((double)i * M_PI / 12.0);

363 v = FIXR(f / (1.0 + f));

364 } else {

365 v = FIXR(1.0);

366 }

367 is_table[0][ i] = v;

368 is_table[1][6 - i] = v;

369 }

370 /* invalid values */

371 for (i = 7; i < 16; i++)

372 is_table[0][i] = is_table[1][i] = 0.0;

373

374 for (i = 0; i < 16; i++) {

375 double f;

376 int e, k;

377

378 for (j = 0; j < 2; j++) {

379 e = -(j + 1) * ((i + 1) >> 1);

380 f = exp2(e / 4.0);

381 k = i & 1;

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

383 is_table_lsf[j][k ][i] = FIXR(1.0);

384 av_dlog(NULL, "is_table_lsf %d %d: %f %f\n",

385 i, j, (float) is_table_lsf[j][0][i],

386 (float) is_table_lsf[j][1][i]);

387 }

388 }

389

390 for (i = 0; i < 8; i++) {

391 float ci, cs, ca;

392 ci = ci_table[i];

393 cs = 1.0 / sqrt(1.0 + ci * ci);

394 ca = cs * ci;

395 #if !USE_FLOATS

396 csa_table[i][0] = FIXHR(cs/4);

397 csa_table[i][1] = FIXHR(ca/4);

398 csa_table[i][2] = FIXHR(ca/4) + FIXHR(cs/4);

399 csa_table[i][3] = FIXHR(ca/4) - FIXHR(cs/4);

400 #else

401 csa_table[i][0] = cs;

402 csa_table[i][1] = ca;

403 csa_table[i][2] = ca + cs;

404 csa_table[i][3] = ca - cs;

405 #endif

406 }

407 }

408

409 #if USE_FLOATS

410 static av_cold int decode_close(AVCodecContext * avctx)

411 {

412 MPADecodeContext *s = avctx->priv_data;

413 av_freep(&s->fdsp);

414

415 return 0;

416 }

417 #endif

418

419 static av_cold int decode_init(AVCodecContext * avctx)

420 {

421 static int initialized_tables = 0;

422 MPADecodeContext *s = avctx->priv_data;

423

424 if (!initialized_tables) {

425 decode_init_static();

426 initialized_tables = 1;

427 }

428

429 s->avctx = avctx;

430

431 #if USE_FLOATS

432 s->fdsp = avpriv_float_dsp_alloc(avctx->flags & CODEC_FLAG_BITEXACT);

433 if (!s->fdsp)

434 return AVERROR(ENOMEM);

435 #endif

436

437 ff_mpadsp_init(&s->mpadsp);

438

439 if (avctx->request_sample_fmt == OUT_FMT &&

440 avctx->codec_id != AV_CODEC_ID_MP3ON4)

441 avctx->sample_fmt = OUT_FMT;

442 else

443 avctx->sample_fmt = OUT_FMT_P;

444 s->err_recognition = avctx->err_recognition;

445

446 if (avctx->codec_id == AV_CODEC_ID_MP3ADU)

447 s->adu_mode = 1;

448

449 return 0;

450 }

451

452 #define C3 FIXHR(0.86602540378443864676/2)

453 #define C4 FIXHR(0.70710678118654752439/2) //0.5 / cos(pi*(9)/36)

454 #define C5 FIXHR(0.51763809020504152469/2) //0.5 / cos(pi*(5)/36)

455 #define C6 FIXHR(1.93185165257813657349/4) //0.5 / cos(pi*(15)/36)

456

457 /* 12 points IMDCT. We compute it "by hand" by factorizing obvious

458 cases. */

459 static void imdct12(INTFLOAT *out, INTFLOAT *in)

460 {

461 INTFLOAT in0, in1, in2, in3, in4, in5, t1, t2;

462

463 in0 = in[0*3];

464 in1 = in[1*3] + in[0*3];

465 in2 = in[2*3] + in[1*3];

466 in3 = in[3*3] + in[2*3];

467 in4 = in[4*3] + in[3*3];

468 in5 = in[5*3] + in[4*3];

469 in5 += in3;

470 in3 += in1;

471

472 in2 = MULH3(in2, C3, 2);

473 in3 = MULH3(in3, C3, 4);

474

475 t1 = in0 - in4;

476 t2 = MULH3(in1 - in5, C4, 2);

477

478 out[ 7] =

479 out[10] = t1 + t2;

480 out[ 1] =

481 out[ 4] = t1 - t2;

482

483 in0 += SHR(in4, 1);

484 in4 = in0 + in2;

485 in5 += 2*in1;

486 in1 = MULH3(in5 + in3, C5, 1);

487 out[ 8] =

488 out[ 9] = in4 + in1;

489 out[ 2] =

490 out[ 3] = in4 - in1;

491

492 in0 -= in2;

493 in5 = MULH3(in5 - in3, C6, 2);

494 out[ 0] =

495 out[ 5] = in0 - in5;

496 out[ 6] =

497 out[11] = in0 + in5;

498 }

499

500 /* return the number of decoded frames */

501 static int mp_decode_layer1(MPADecodeContext *s)

502 {

503 int bound, i, v, n, ch, j, mant;

504 uint8_t allocation[MPA_MAX_CHANNELS][SBLIMIT];

505 uint8_t scale_factors[MPA_MAX_CHANNELS][SBLIMIT];

506

507 if (s->mode == MPA_JSTEREO)

508 bound = (s->mode_ext + 1) * 4;

509 else

510 bound = SBLIMIT;

511

512 /* allocation bits */

513 for (i = 0; i < bound; i++) {

514 for (ch = 0; ch < s->nb_channels; ch++) {

515 allocation[ch][i] = get_bits(&s->gb, 4);

516 }

517 }

518 for (i = bound; i < SBLIMIT; i++)

519 allocation[0][i] = get_bits(&s->gb, 4);

520

521 /* scale factors */

522 for (i = 0; i < bound; i++) {

523 for (ch = 0; ch < s->nb_channels; ch++) {

524 if (allocation[ch][i])

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

526 }

527 }

528 for (i = bound; i < SBLIMIT; i++) {

529 if (allocation[0][i]) {

530 scale_factors[0][i] = get_bits(&s->gb, 6);

531 scale_factors[1][i] = get_bits(&s->gb, 6);

532 }

533 }

534

535 /* compute samples */

536 for (j = 0; j < 12; j++) {

537 for (i = 0; i < bound; i++) {

538 for (ch = 0; ch < s->nb_channels; ch++) {

539 n = allocation[ch][i];

540 if (n) {

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

542 v = l1_unscale(n, mant, scale_factors[ch][i]);

543 } else {

544 v = 0;

545 }

546 s->sb_samples[ch][j][i] = v;

547 }

548 }

549 for (i = bound; i < SBLIMIT; i++) {

550 n = allocation[0][i];

551 if (n) {

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

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

554 s->sb_samples[0][j][i] = v;

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

556 s->sb_samples[1][j][i] = v;

557 } else {

558 s->sb_samples[0][j][i] = 0;

559 s->sb_samples[1][j][i] = 0;

560 }

561 }

562 }

563 return 12;

564 }

565

566 static int mp_decode_layer2(MPADecodeContext *s)

567 {

568 int sblimit; /* number of used subbands */

569 const unsigned char *alloc_table;

570 int table, bit_alloc_bits, i, j, ch, bound, v;

571 unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT];

572 unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT];

573 unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3], *sf;

574 int scale, qindex, bits, steps, k, l, m, b;

575

576 /* select decoding table */

577 table = ff_mpa_l2_select_table(s->bit_rate / 1000, s->nb_channels,

578 s->sample_rate, s->lsf);

579 sblimit = ff_mpa_sblimit_table[table];

580 alloc_table = ff_mpa_alloc_tables[table];

581

582 if (s->mode == MPA_JSTEREO)

583 bound = (s->mode_ext + 1) * 4;

584 else

585 bound = sblimit;

586

587 av_dlog(s->avctx, "bound=%d sblimit=%d\n", bound, sblimit);

588

589 /* sanity check */

590 if (bound > sblimit)

591 bound = sblimit;

592

593 /* parse bit allocation */

594 j = 0;

595 for (i = 0; i < bound; i++) {

596 bit_alloc_bits = alloc_table[j];

597 for (ch = 0; ch < s->nb_channels; ch++)

598 bit_alloc[ch][i] = get_bits(&s->gb, bit_alloc_bits);

599 j += 1 << bit_alloc_bits;

600 }

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

602 bit_alloc_bits = alloc_table[j];

603 v = get_bits(&s->gb, bit_alloc_bits);

604 bit_alloc[0][i] = v;

605 bit_alloc[1][i] = v;

606 j += 1 << bit_alloc_bits;

607 }

608

609 /* scale codes */

610 for (i = 0; i < sblimit; i++) {

611 for (ch = 0; ch < s->nb_channels; ch++) {

612 if (bit_alloc[ch][i])

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

614 }

615 }

616

617 /* scale factors */

618 for (i = 0; i < sblimit; i++) {

619 for (ch = 0; ch < s->nb_channels; ch++) {

620 if (bit_alloc[ch][i]) {

621 sf = scale_factors[ch][i];

622 switch (scale_code[ch][i]) {

623 default:

624 case 0:

625 sf[0] = get_bits(&s->gb, 6);

626 sf[1] = get_bits(&s->gb, 6);

627 sf[2] = get_bits(&s->gb, 6);

628 break;

629 case 2:

630 sf[0] = get_bits(&s->gb, 6);

631 sf[1] = sf[0];

632 sf[2] = sf[0];

633 break;

634 case 1:

635 sf[0] = get_bits(&s->gb, 6);

636 sf[2] = get_bits(&s->gb, 6);

637 sf[1] = sf[0];

638 break;

639 case 3:

640 sf[0] = get_bits(&s->gb, 6);

641 sf[2] = get_bits(&s->gb, 6);

642 sf[1] = sf[2];

643 break;

644 }

645 }

646 }

647 }

648

649 /* samples */

650 for (k = 0; k < 3; k++) {

651 for (l = 0; l < 12; l += 3) {

652 j = 0;

653 for (i = 0; i < bound; i++) {

654 bit_alloc_bits = alloc_table[j];

655 for (ch = 0; ch < s->nb_channels; ch++) {

656 b = bit_alloc[ch][i];

657 if (b) {

658 scale = scale_factors[ch][i][k];

659 qindex = alloc_table[j+b];

660 bits = ff_mpa_quant_bits[qindex];

661 if (bits < 0) {

662 int v2;

663 /* 3 values at the same time */

664 v = get_bits(&s->gb, -bits);

665 v2 = division_tabs[qindex][v];

666 steps = ff_mpa_quant_steps[qindex];

667

668 s->sb_samples[ch][k * 12 + l + 0][i] =

669 l2_unscale_group(steps, v2 & 15, scale);

670 s->sb_samples[ch][k * 12 + l + 1][i] =

671 l2_unscale_group(steps, (v2 >> 4) & 15, scale);

672 s->sb_samples[ch][k * 12 + l + 2][i] =

673 l2_unscale_group(steps, v2 >> 8 , scale);

674 } else {

675 for (m = 0; m < 3; m++) {

676 v = get_bits(&s->gb, bits);

677 v = l1_unscale(bits - 1, v, scale);

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

679 }

680 }

681 } else {

682 s->sb_samples[ch][k * 12 + l + 0][i] = 0;

683 s->sb_samples[ch][k * 12 + l + 1][i] = 0;

684 s->sb_samples[ch][k * 12 + l + 2][i] = 0;

685 }

686 }

687 /* next subband in alloc table */

688 j += 1 << bit_alloc_bits;

689 }

690 /* XXX: find a way to avoid this duplication of code */

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

692 bit_alloc_bits = alloc_table[j];

693 b = bit_alloc[0][i];

694 if (b) {

695 int mant, scale0, scale1;

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

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

698 qindex = alloc_table[j+b];

699 bits = ff_mpa_quant_bits[qindex];

700 if (bits < 0) {

701 /* 3 values at the same time */

702 v = get_bits(&s->gb, -bits);

703 steps = ff_mpa_quant_steps[qindex];

704 mant = v % steps;

705 v = v / steps;

706 s->sb_samples[0][k * 12 + l + 0][i] =

707 l2_unscale_group(steps, mant, scale0);

708 s->sb_samples[1][k * 12 + l + 0][i] =

709 l2_unscale_group(steps, mant, scale1);

710 mant = v % steps;

711 v = v / steps;

712 s->sb_samples[0][k * 12 + l + 1][i] =

713 l2_unscale_group(steps, mant, scale0);

714 s->sb_samples[1][k * 12 + l + 1][i] =

715 l2_unscale_group(steps, mant, scale1);

716 s->sb_samples[0][k * 12 + l + 2][i] =

717 l2_unscale_group(steps, v, scale0);

718 s->sb_samples[1][k * 12 + l + 2][i] =

719 l2_unscale_group(steps, v, scale1);

720 } else {

721 for (m = 0; m < 3; m++) {

722 mant = get_bits(&s->gb, bits);

723 s->sb_samples[0][k * 12 + l + m][i] =

724 l1_unscale(bits - 1, mant, scale0);

725 s->sb_samples[1][k * 12 + l + m][i] =

726 l1_unscale(bits - 1, mant, scale1);

727 }

728 }

729 } else {

730 s->sb_samples[0][k * 12 + l + 0][i] = 0;

731 s->sb_samples[0][k * 12 + l + 1][i] = 0;

732 s->sb_samples[0][k * 12 + l + 2][i] = 0;

733 s->sb_samples[1][k * 12 + l + 0][i] = 0;

734 s->sb_samples[1][k * 12 + l + 1][i] = 0;

735 s->sb_samples[1][k * 12 + l + 2][i] = 0;

736 }

737 /* next subband in alloc table */

738 j += 1 << bit_alloc_bits;

739 }

740 /* fill remaining samples to zero */

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

742 for (ch = 0; ch < s->nb_channels; ch++) {

743 s->sb_samples[ch][k * 12 + l + 0][i] = 0;

744 s->sb_samples[ch][k * 12 + l + 1][i] = 0;

745 s->sb_samples[ch][k * 12 + l + 2][i] = 0;

746 }

747 }

748 }

749 }

750 return 3 * 12;

751 }

752

753 #define SPLIT(dst,sf,n) \

754 if (n == 3) { \

755 int m = (sf * 171) >> 9; \

756 dst = sf - 3 * m; \

757 sf = m; \

758 } else if (n == 4) { \

759 dst = sf & 3; \

760 sf >>= 2; \

761 } else if (n == 5) { \

762 int m = (sf * 205) >> 10; \

763 dst = sf - 5 * m; \

764 sf = m; \

765 } else if (n == 6) { \

766 int m = (sf * 171) >> 10; \

767 dst = sf - 6 * m; \

768 sf = m; \

769 } else { \

770 dst = 0; \

771 }

772

773 static av_always_inline void lsf_sf_expand(int *slen, int sf, int n1, int n2,

774 int n3)

775 {

776 SPLIT(slen[3], sf, n3)

777 SPLIT(slen[2], sf, n2)

778 SPLIT(slen[1], sf, n1)

779 slen[0] = sf;

780 }

781

782 static void exponents_from_scale_factors(MPADecodeContext *s, GranuleDef *g,

783 int16_t *exponents)

784 {

785 const uint8_t *bstab, *pretab;

786 int len, i, j, k, l, v0, shift, gain, gains[3];

787 int16_t *exp_ptr;

788

789 exp_ptr = exponents;

790 gain = g->global_gain - 210;

791 shift = g->scalefac_scale + 1;

792

793 bstab = band_size_long[s->sample_rate_index];

794 pretab = mpa_pretab[g->preflag];

795 for (i = 0; i < g->long_end; i++) {

796 v0 = gain - ((g->scale_factors[i] + pretab[i]) << shift) + 400;

797 len = bstab[i];

798 for (j = len; j > 0; j--)

799 *exp_ptr++ = v0;

800 }

801

802 if (g->short_start < 13) {

803 bstab = band_size_short[s->sample_rate_index];

804 gains[0] = gain - (g->subblock_gain[0] << 3);

805 gains[1] = gain - (g->subblock_gain[1] << 3);

806 gains[2] = gain - (g->subblock_gain[2] << 3);

807 k = g->long_end;

808 for (i = g->short_start; i < 13; i++) {

809 len = bstab[i];

810 for (l = 0; l < 3; l++) {

811 v0 = gains[l] - (g->scale_factors[k++] << shift) + 400;

812 for (j = len; j > 0; j--)

813 *exp_ptr++ = v0;

814 }

815 }

816 }

817 }

818

819 /* handle n = 0 too */

820 static inline int get_bitsz(GetBitContext *s, int n)

821 {

822 return n ? get_bits(s, n) : 0;

823 }

824

825

826 static void switch_buffer(MPADecodeContext *s, int *pos, int *end_pos,

827 int *end_pos2)

828 {

829 if (s->in_gb.buffer && *pos >= s->gb.size_in_bits) {

830 s->gb = s->in_gb;

831 s->in_gb.buffer = NULL;

832 av_assert2((get_bits_count(&s->gb) & 7) == 0);

833 skip_bits_long(&s->gb, *pos - *end_pos);

834 *end_pos2 =

835 *end_pos = *end_pos2 + get_bits_count(&s->gb) - *pos;

836 *pos = get_bits_count(&s->gb);

837 }

838 }

839

840 /* Following is a optimized code for

841 INTFLOAT v = *src

842 if(get_bits1(&s->gb))

843 v = -v;

844 *dst = v;

845 */

846 #if USE_FLOATS

847 #define READ_FLIP_SIGN(dst,src) \

848 v = AV_RN32A(src) ^ (get_bits1(&s->gb) << 31); \

849 AV_WN32A(dst, v);

850 #else

851 #define READ_FLIP_SIGN(dst,src) \

852 v = -get_bits1(&s->gb); \

853 *(dst) = (*(src) ^ v) - v;

854 #endif

855

856 static int huffman_decode(MPADecodeContext *s, GranuleDef *g,

857 int16_t *exponents, int end_pos2)

858 {

859 int s_index;

860 int i;

861 int last_pos, bits_left;

862 VLC *vlc;

863 int end_pos = FFMIN(end_pos2, s->gb.size_in_bits);

864

865 /* low frequencies (called big values) */

866 s_index = 0;

867 for (i = 0; i < 3; i++) {

868 int j, k, l, linbits;

869 j = g->region_size[i];

870 if (j == 0)

871 continue;

872 /* select vlc table */

873 k = g->table_select[i];

874 l = mpa_huff_data[k][0];

875 linbits = mpa_huff_data[k][1];

876 vlc = &huff_vlc[l];

877

878 if (!l) {

879 memset(&g->sb_hybrid[s_index], 0, sizeof(*g->sb_hybrid) * 2 * j);

880 s_index += 2 * j;

881 continue;

882 }

883

884 /* read huffcode and compute each couple */

885 for (; j > 0; j--) {

886 int exponent, x, y;

887 int v;

888 int pos = get_bits_count(&s->gb);

889

890 if (pos >= end_pos){

891 switch_buffer(s, &pos, &end_pos, &end_pos2);

892 if (pos >= end_pos)

893 break;

894 }

895 y = get_vlc2(&s->gb, vlc->table, 7, 3);

896

897 if (!y) {

898 g->sb_hybrid[s_index ] =

899 g->sb_hybrid[s_index+1] = 0;

900 s_index += 2;

901 continue;

902 }

903

904 exponent= exponents[s_index];

905

906 av_dlog(s->avctx, "region=%d n=%d x=%d y=%d exp=%d\n",

907 i, g->region_size[i] - j, x, y, exponent);

908 if (y & 16) {

909 x = y >> 5;

910 y = y & 0x0f;

911 if (x < 15) {

912 READ_FLIP_SIGN(g->sb_hybrid + s_index, RENAME(expval_table)[exponent] + x)

913 } else {

914 x += get_bitsz(&s->gb, linbits);

915 v = l3_unscale(x, exponent);

916 if (get_bits1(&s->gb))

917 v = -v;

918 g->sb_hybrid[s_index] = v;

919 }

920 if (y < 15) {

921 READ_FLIP_SIGN(g->sb_hybrid + s_index + 1, RENAME(expval_table)[exponent] + y)

922 } else {

923 y += get_bitsz(&s->gb, linbits);

924 v = l3_unscale(y, exponent);

925 if (get_bits1(&s->gb))

926 v = -v;

927 g->sb_hybrid[s_index+1] = v;

928 }

929 } else {

930 x = y >> 5;

931 y = y & 0x0f;

932 x += y;

933 if (x < 15) {

934 READ_FLIP_SIGN(g->sb_hybrid + s_index + !!y, RENAME(expval_table)[exponent] + x)

935 } else {

936 x += get_bitsz(&s->gb, linbits);

937 v = l3_unscale(x, exponent);

938 if (get_bits1(&s->gb))

939 v = -v;

940 g->sb_hybrid[s_index+!!y] = v;

941 }

942 g->sb_hybrid[s_index + !y] = 0;

943 }

944 s_index += 2;

945 }

946 }

947

948 /* high frequencies */

949 vlc = &huff_quad_vlc[g->count1table_select];

950 last_pos = 0;

951 while (s_index <= 572) {

952 int pos, code;

953 pos = get_bits_count(&s->gb);

954 if (pos >= end_pos) {

955 if (pos > end_pos2 && last_pos) {

956 /* some encoders generate an incorrect size for this

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

958 s_index -= 4;

959 skip_bits_long(&s->gb, last_pos - pos);

960 av_log(s->avctx, AV_LOG_INFO, "overread, skip %d enddists: %d %d\n", last_pos - pos, end_pos-pos, end_pos2-pos);

961 if(s->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT))

962 s_index=0;

963 break;

964 }

965 switch_buffer(s, &pos, &end_pos, &end_pos2);

966 if (pos >= end_pos)

967 break;

968 }

969 last_pos = pos;

970

971 code = get_vlc2(&s->gb, vlc->table, vlc->bits, 1);

972 av_dlog(s->avctx, "t=%d code=%d\n", g->count1table_select, code);

973 g->sb_hybrid[s_index+0] =

974 g->sb_hybrid[s_index+1] =

975 g->sb_hybrid[s_index+2] =

976 g->sb_hybrid[s_index+3] = 0;

977 while (code) {

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

979 int v;

980 int pos = s_index + idxtab[code];

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

982 READ_FLIP_SIGN(g->sb_hybrid + pos, RENAME(exp_table)+exponents[pos])

983 }

984 s_index += 4;

985 }

986 /* skip extension bits */

987 bits_left = end_pos2 - get_bits_count(&s->gb);

988 if (bits_left < 0 && (s->err_recognition & (AV_EF_BUFFER|AV_EF_COMPLIANT))) {

989 av_log(s->avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);

990 s_index=0;

991 } else if (bits_left > 0 && (s->err_recognition & (AV_EF_BUFFER|AV_EF_AGGRESSIVE))) {

992 av_log(s->avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);

993 s_index = 0;

994 }

995 memset(&g->sb_hybrid[s_index], 0, sizeof(*g->sb_hybrid) * (576 - s_index));

996 skip_bits_long(&s->gb, bits_left);

997

998 i = get_bits_count(&s->gb);

999 switch_buffer(s, &i, &end_pos, &end_pos2);

1000

1001 return 0;

1002 }

1003

1004 /* Reorder short blocks from bitstream order to interleaved order. It

1005 would be faster to do it in parsing, but the code would be far more

1006 complicated */

1007 static void reorder_block(MPADecodeContext *s, GranuleDef *g)

1008 {

1009 int i, j, len;

1010 INTFLOAT *ptr, *dst, *ptr1;

1011 INTFLOAT tmp[576];

1012

1013 if (g->block_type != 2)

1014 return;

1015

1016 if (g->switch_point) {

1017 if (s->sample_rate_index != 8)

1018 ptr = g->sb_hybrid + 36;

1019 else

1020 ptr = g->sb_hybrid + 72;

1021 } else {

1022 ptr = g->sb_hybrid;

1023 }

1024

1025 for (i = g->short_start; i < 13; i++) {

1026 len = band_size_short[s->sample_rate_index][i];

1027 ptr1 = ptr;

1028 dst = tmp;

1029 for (j = len; j > 0; j--) {

1030 *dst++ = ptr[0*len];

1031 *dst++ = ptr[1*len];

1032 *dst++ = ptr[2*len];

1033 ptr++;

1034 }

1035 ptr += 2 * len;

1036 memcpy(ptr1, tmp, len * 3 * sizeof(*ptr1));

1037 }

1038 }

1039

1040 #define ISQRT2 FIXR(0.70710678118654752440)

1041

1042 static void compute_stereo(MPADecodeContext *s, GranuleDef *g0, GranuleDef *g1)

1043 {

1044 int i, j, k, l;

1045 int sf_max, sf, len, non_zero_found;

1046 INTFLOAT (*is_tab)[16], *tab0, *tab1, tmp0, tmp1, v1, v2;

1047 int non_zero_found_short[3];

1048

1049 /* intensity stereo */

1050 if (s->mode_ext & MODE_EXT_I_STEREO) {

1051 if (!s->lsf) {

1052 is_tab = is_table;

1053 sf_max = 7;

1054 } else {

1055 is_tab = is_table_lsf[g1->scalefac_compress & 1];

1056 sf_max = 16;

1057 }

1058

1059 tab0 = g0->sb_hybrid + 576;

1060 tab1 = g1->sb_hybrid + 576;

1061

1062 non_zero_found_short[0] = 0;

1063 non_zero_found_short[1] = 0;

1064 non_zero_found_short[2] = 0;

1065 k = (13 - g1->short_start) * 3 + g1->long_end - 3;

1066 for (i = 12; i >= g1->short_start; i--) {

1067 /* for last band, use previous scale factor */

1068 if (i != 11)

1069 k -= 3;

1070 len = band_size_short[s->sample_rate_index][i];

1071 for (l = 2; l >= 0; l--) {

1072 tab0 -= len;

1073 tab1 -= len;

1074 if (!non_zero_found_short[l]) {

1075 /* test if non zero band. if so, stop doing i-stereo */

1076 for (j = 0; j < len; j++) {

1077 if (tab1[j] != 0) {

1078 non_zero_found_short[l] = 1;

1079 goto found1;

1080 }

1081 }

1082 sf = g1->scale_factors[k + l];

1083 if (sf >= sf_max)

1084 goto found1;

1085

1086 v1 = is_tab[0][sf];

1087 v2 = is_tab[1][sf];

1088 for (j = 0; j < len; j++) {

1089 tmp0 = tab0[j];

1090 tab0[j] = MULLx(tmp0, v1, FRAC_BITS);

1091 tab1[j] = MULLx(tmp0, v2, FRAC_BITS);

1092 }

1093 } else {

1094 found1:

1095 if (s->mode_ext & MODE_EXT_MS_STEREO) {

1096 /* lower part of the spectrum : do ms stereo

1097 if enabled */

1098 for (j = 0; j < len; j++) {

1099 tmp0 = tab0[j];

1100 tmp1 = tab1[j];

1101 tab0[j] = MULLx(tmp0 + tmp1, ISQRT2, FRAC_BITS);

1102 tab1[j] = MULLx(tmp0 - tmp1, ISQRT2, FRAC_BITS);

1103 }

1104 }

1105 }

1106 }

1107 }

1108

1109 non_zero_found = non_zero_found_short[0] |

1110 non_zero_found_short[1] |

1111 non_zero_found_short[2];

1112

1113 for (i = g1->long_end - 1;i >= 0;i--) {

1114 len = band_size_long[s->sample_rate_index][i];

1115 tab0 -= len;

1116 tab1 -= len;

1117 /* test if non zero band. if so, stop doing i-stereo */

1118 if (!non_zero_found) {

1119 for (j = 0; j < len; j++) {

1120 if (tab1[j] != 0) {

1121 non_zero_found = 1;

1122 goto found2;

1123 }

1124 }

1125 /* for last band, use previous scale factor */

1126 k = (i == 21) ? 20 : i;

1127 sf = g1->scale_factors[k];

1128 if (sf >= sf_max)

1129 goto found2;

1130 v1 = is_tab[0][sf];

1131 v2 = is_tab[1][sf];

1132 for (j = 0; j < len; j++) {

1133 tmp0 = tab0[j];

1134 tab0[j] = MULLx(tmp0, v1, FRAC_BITS);

1135 tab1[j] = MULLx(tmp0, v2, FRAC_BITS);

1136 }

1137 } else {

1138 found2:

1139 if (s->mode_ext & MODE_EXT_MS_STEREO) {

1140 /* lower part of the spectrum : do ms stereo

1141 if enabled */

1142 for (j = 0; j < len; j++) {

1143 tmp0 = tab0[j];

1144 tmp1 = tab1[j];

1145 tab0[j] = MULLx(tmp0 + tmp1, ISQRT2, FRAC_BITS);

1146 tab1[j] = MULLx(tmp0 - tmp1, ISQRT2, FRAC_BITS);

1147 }

1148 }

1149 }

1150 }

1151 } else if (s->mode_ext & MODE_EXT_MS_STEREO) {

1152 /* ms stereo ONLY */

1153 /* NOTE: the 1/sqrt(2) normalization factor is included in the

1154 global gain */

1155 #if USE_FLOATS

1156 s->fdsp->butterflies_float(g0->sb_hybrid, g1->sb_hybrid, 576);

1157 #else

1158 tab0 = g0->sb_hybrid;

1159 tab1 = g1->sb_hybrid;

1160 for (i = 0; i < 576; i++) {

1161 tmp0 = tab0[i];

1162 tmp1 = tab1[i];

1163 tab0[i] = tmp0 + tmp1;

1164 tab1[i] = tmp0 - tmp1;

1165 }

1166 #endif

1167 }

1168 }

1169

1170 #if USE_FLOATS

1171 #if HAVE_MIPSFPU

1172 # include "mips/compute_antialias_float.h"

1173 #endif /* HAVE_MIPSFPU */

1174 #else

1175 #if HAVE_MIPSDSPR1

1176 # include "mips/compute_antialias_fixed.h"

1177 #endif /* HAVE_MIPSDSPR1 */

1178 #endif /* USE_FLOATS */

1179

1180 #ifndef compute_antialias

1181 #if USE_FLOATS

1182 #define AA(j) do { \

1183 float tmp0 = ptr[-1-j]; \

1184 float tmp1 = ptr[ j]; \

1185 ptr[-1-j] = tmp0 * csa_table[j][0] - tmp1 * csa_table[j][1]; \

1186 ptr[ j] = tmp0 * csa_table[j][1] + tmp1 * csa_table[j][0]; \

1187 } while (0)

1188 #else

1189 #define AA(j) do { \

1190 int tmp0 = ptr[-1-j]; \

1191 int tmp1 = ptr[ j]; \

1192 int tmp2 = MULH(tmp0 + tmp1, csa_table[j][0]); \

1193 ptr[-1-j] = 4 * (tmp2 - MULH(tmp1, csa_table[j][2])); \

1194 ptr[ j] = 4 * (tmp2 + MULH(tmp0, csa_table[j][3])); \

1195 } while (0)

1196 #endif

1197

1198 static void compute_antialias(MPADecodeContext *s, GranuleDef *g)

1199 {

1200 INTFLOAT *ptr;

1201 int n, i;

1202

1203 /* we antialias only "long" bands */

1204 if (g->block_type == 2) {

1205 if (!g->switch_point)

1206 return;

1207 /* XXX: check this for 8000Hz case */

1208 n = 1;

1209 } else {

1210 n = SBLIMIT - 1;

1211 }

1212

1213 ptr = g->sb_hybrid + 18;

1214 for (i = n; i > 0; i--) {

1215 AA(0);

1216 AA(1);

1217 AA(2);

1218 AA(3);

1219 AA(4);

1220 AA(5);

1221 AA(6);

1222 AA(7);

1223

1224 ptr += 18;

1225 }

1226 }

1227 #endif /* compute_antialias */

1228

1229 static void compute_imdct(MPADecodeContext *s, GranuleDef *g,

1230 INTFLOAT *sb_samples, INTFLOAT *mdct_buf)

1231 {

1232 INTFLOAT *win, *out_ptr, *ptr, *buf, *ptr1;

1233 INTFLOAT out2[12];

1234 int i, j, mdct_long_end, sblimit;

1235

1236 /* find last non zero block */

1237 ptr = g->sb_hybrid + 576;

1238 ptr1 = g->sb_hybrid + 2 * 18;

1239 while (ptr >= ptr1) {

1240 int32_t *p;

1241 ptr -= 6;

1242 p = (int32_t*)ptr;

1243 if (p[0] | p[1] | p[2] | p[3] | p[4] | p[5])

1244 break;

1245 }

1246 sblimit = ((ptr - g->sb_hybrid) / 18) + 1;

1247

1248 if (g->block_type == 2) {

1249 /* XXX: check for 8000 Hz */

1250 if (g->switch_point)

1251 mdct_long_end = 2;

1252 else

1253 mdct_long_end = 0;

1254 } else {

1255 mdct_long_end = sblimit;

1256 }

1257

1258 s->mpadsp.RENAME(imdct36_blocks)(sb_samples, mdct_buf, g->sb_hybrid,

1259 mdct_long_end, g->switch_point,

1260 g->block_type);

1261

1262 buf = mdct_buf + 4*18*(mdct_long_end >> 2) + (mdct_long_end & 3);

1263 ptr = g->sb_hybrid + 18 * mdct_long_end;

1264

1265 for (j = mdct_long_end; j < sblimit; j++) {

1266 /* select frequency inversion */

1267 win = RENAME(ff_mdct_win)[2 + (4 & -(j & 1))];

1268 out_ptr = sb_samples + j;

1269

1270 for (i = 0; i < 6; i++) {

1271 *out_ptr = buf[4*i];

1272 out_ptr += SBLIMIT;

1273 }

1274 imdct12(out2, ptr + 0);

1275 for (i = 0; i < 6; i++) {

1276 *out_ptr = MULH3(out2[i ], win[i ], 1) + buf[4*(i + 6*1)];

1277 buf[4*(i + 6*2)] = MULH3(out2[i + 6], win[i + 6], 1);

1278 out_ptr += SBLIMIT;

1279 }

1280 imdct12(out2, ptr + 1);

1281 for (i = 0; i < 6; i++) {

1282 *out_ptr = MULH3(out2[i ], win[i ], 1) + buf[4*(i + 6*2)];

1283 buf[4*(i + 6*0)] = MULH3(out2[i + 6], win[i + 6], 1);

1284 out_ptr += SBLIMIT;

1285 }

1286 imdct12(out2, ptr + 2);

1287 for (i = 0; i < 6; i++) {

1288 buf[4*(i + 6*0)] = MULH3(out2[i ], win[i ], 1) + buf[4*(i + 6*0)];

1289 buf[4*(i + 6*1)] = MULH3(out2[i + 6], win[i + 6], 1);

1290 buf[4*(i + 6*2)] = 0;

1291 }

1292 ptr += 18;

1293 buf += (j&3) != 3 ? 1 : (4*18-3);

1294 }

1295 /* zero bands */

1296 for (j = sblimit; j < SBLIMIT; j++) {

1297 /* overlap */

1298 out_ptr = sb_samples + j;

1299 for (i = 0; i < 18; i++) {

1300 *out_ptr = buf[4*i];

1301 buf[4*i] = 0;

1302 out_ptr += SBLIMIT;

1303 }

1304 buf += (j&3) != 3 ? 1 : (4*18-3);

1305 }

1306 }

1307

1308 /* main layer3 decoding function */

1309 static int mp_decode_layer3(MPADecodeContext *s)

1310 {

1311 int nb_granules, main_data_begin;

1312 int gr, ch, blocksplit_flag, i, j, k, n, bits_pos;

1313 GranuleDef *g;

1314 int16_t exponents[576]; //FIXME try INTFLOAT

1315

1316 /* read side info */

1317 if (s->lsf) {

1318 main_data_begin = get_bits(&s->gb, 8);

1319 skip_bits(&s->gb, s->nb_channels);

1320 nb_granules = 1;

1321 } else {

1322 main_data_begin = get_bits(&s->gb, 9);

1323 if (s->nb_channels == 2)

1324 skip_bits(&s->gb, 3);

1325 else

1326 skip_bits(&s->gb, 5);

1327 nb_granules = 2;

1328 for (ch = 0; ch < s->nb_channels; ch++) {

1329 s->granules[ch][0].scfsi = 0;/* all scale factors are transmitted */

1330 s->granules[ch][1].scfsi = get_bits(&s->gb, 4);

1331 }

1332 }

1333

1334 for (gr = 0; gr < nb_granules; gr++) {

1335 for (ch = 0; ch < s->nb_channels; ch++) {

1336 av_dlog(s->avctx, "gr=%d ch=%d: side_info\n", gr, ch);

1337 g = &s->granules[ch][gr];

1338 g->part2_3_length = get_bits(&s->gb, 12);

1339 g->big_values = get_bits(&s->gb, 9);

1340 if (g->big_values > 288) {

1341 av_log(s->avctx, AV_LOG_ERROR, "big_values too big\n");

1342 return AVERROR_INVALIDDATA;

1343 }

1344

1345 g->global_gain = get_bits(&s->gb, 8);

1346 /* if MS stereo only is selected, we precompute the

1347 1/sqrt(2) renormalization factor */

1348 if ((s->mode_ext & (MODE_EXT_MS_STEREO | MODE_EXT_I_STEREO)) ==

1349 MODE_EXT_MS_STEREO)

1350 g->global_gain -= 2;

1351 if (s->lsf)

1352 g->scalefac_compress = get_bits(&s->gb, 9);

1353 else

1354 g->scalefac_compress = get_bits(&s->gb, 4);

1355 blocksplit_flag = get_bits1(&s->gb);

1356 if (blocksplit_flag) {

1357 g->block_type = get_bits(&s->gb, 2);

1358 if (g->block_type == 0) {

1359 av_log(s->avctx, AV_LOG_ERROR, "invalid block type\n");

1360 return AVERROR_INVALIDDATA;

1361 }

1362 g->switch_point = get_bits1(&s->gb);

1363 for (i = 0; i < 2; i++)

1364 g->table_select[i] = get_bits(&s->gb, 5);

1365 for (i = 0; i < 3; i++)

1366 g->subblock_gain[i] = get_bits(&s->gb, 3);

1367 init_short_region(s, g);

1368 } else {

1369 int region_address1, region_address2;

1370 g->block_type = 0;

1371 g->switch_point = 0;

1372 for (i = 0; i < 3; i++)

1373 g->table_select[i] = get_bits(&s->gb, 5);

1374 /* compute huffman coded region sizes */

1375 region_address1 = get_bits(&s->gb, 4);

1376 region_address2 = get_bits(&s->gb, 3);

1377 av_dlog(s->avctx, "region1=%d region2=%d\n",

1378 region_address1, region_address2);

1379 init_long_region(s, g, region_address1, region_address2);

1380 }

1381 region_offset2size(g);

1382 compute_band_indexes(s, g);

1383

1384 g->preflag = 0;

1385 if (!s->lsf)

1386 g->preflag = get_bits1(&s->gb);

1387 g->scalefac_scale = get_bits1(&s->gb);

1388 g->count1table_select = get_bits1(&s->gb);

1389 av_dlog(s->avctx, "block_type=%d switch_point=%d\n",

1390 g->block_type, g->switch_point);

1391 }

1392 }

1393

1394 if (!s->adu_mode) {

1395 int skip;

1396 const uint8_t *ptr = s->gb.buffer + (get_bits_count(&s->gb)>>3);

1397 int extrasize = av_clip(get_bits_left(&s->gb) >> 3, 0, EXTRABYTES);

1398 av_assert1((get_bits_count(&s->gb) & 7) == 0);

1399 /* now we get bits from the main_data_begin offset */

1400 av_dlog(s->avctx, "seekback:%d, lastbuf:%d\n",

1401 main_data_begin, s->last_buf_size);

1402

1403 memcpy(s->last_buf + s->last_buf_size, ptr, extrasize);

1404 s->in_gb = s->gb;

1405 init_get_bits(&s->gb, s->last_buf, s->last_buf_size*8);

1406 #if !UNCHECKED_BITSTREAM_READER

1407 s->gb.size_in_bits_plus8 += FFMAX(extrasize, LAST_BUF_SIZE - s->last_buf_size) * 8;

1408 #endif

1409 s->last_buf_size <<= 3;

1410 for (gr = 0; gr < nb_granules && (s->last_buf_size >> 3) < main_data_begin; gr++) {

1411 for (ch = 0; ch < s->nb_channels; ch++) {

1412 g = &s->granules[ch][gr];

1413 s->last_buf_size += g->part2_3_length;

1414 memset(g->sb_hybrid, 0, sizeof(g->sb_hybrid));

1415 compute_imdct(s, g, &s->sb_samples[ch][18 * gr][0], s->mdct_buf[ch]);

1416 }

1417 }

1418 skip = s->last_buf_size - 8 * main_data_begin;

1419 if (skip >= s->gb.size_in_bits && s->in_gb.buffer) {

1420 skip_bits_long(&s->in_gb, skip - s->gb.size_in_bits);

1421 s->gb = s->in_gb;

1422 s->in_gb.buffer = NULL;

1423 } else {

1424 skip_bits_long(&s->gb, skip);

1425 }

1426 } else {

1427 gr = 0;

1428 }

1429

1430 for (; gr < nb_granules; gr++) {

1431 for (ch = 0; ch < s->nb_channels; ch++) {

1432 g = &s->granules[ch][gr];

1433 bits_pos = get_bits_count(&s->gb);

1434

1435 if (!s->lsf) {

1436 uint8_t *sc;

1437 int slen, slen1, slen2;

1438

1439 /* MPEG1 scale factors */

1440 slen1 = slen_table[0][g->scalefac_compress];

1441 slen2 = slen_table[1][g->scalefac_compress];

1442 av_dlog(s->avctx, "slen1=%d slen2=%d\n", slen1, slen2);

1443 if (g->block_type == 2) {

1444 n = g->switch_point ? 17 : 18;

1445 j = 0;

1446 if (slen1) {

1447 for (i = 0; i < n; i++)

1448 g->scale_factors[j++] = get_bits(&s->gb, slen1);

1449 } else {

1450 for (i = 0; i < n; i++)

1451 g->scale_factors[j++] = 0;

1452 }

1453 if (slen2) {

1454 for (i = 0; i < 18; i++)

1455 g->scale_factors[j++] = get_bits(&s->gb, slen2);

1456 for (i = 0; i < 3; i++)

1457 g->scale_factors[j++] = 0;

1458 } else {

1459 for (i = 0; i < 21; i++)

1460 g->scale_factors[j++] = 0;

1461 }

1462 } else {

1463 sc = s->granules[ch][0].scale_factors;

1464 j = 0;

1465 for (k = 0; k < 4; k++) {

1466 n = k == 0 ? 6 : 5;

1467 if ((g->scfsi & (0x8 >> k)) == 0) {

1468 slen = (k < 2) ? slen1 : slen2;

1469 if (slen) {

1470 for (i = 0; i < n; i++)

1471 g->scale_factors[j++] = get_bits(&s->gb, slen);

1472 } else {

1473 for (i = 0; i < n; i++)

1474 g->scale_factors[j++] = 0;

1475 }

1476 } else {

1477 /* simply copy from last granule */

1478 for (i = 0; i < n; i++) {

1479 g->scale_factors[j] = sc[j];

1480 j++;

1481 }

1482 }

1483 }

1484 g->scale_factors[j++] = 0;

1485 }

1486 } else {

1487 int tindex, tindex2, slen[4], sl, sf;

1488

1489 /* LSF scale factors */

1490 if (g->block_type == 2)

1491 tindex = g->switch_point ? 2 : 1;

1492 else

1493 tindex = 0;

1494

1495 sf = g->scalefac_compress;

1496 if ((s->mode_ext & MODE_EXT_I_STEREO) && ch == 1) {

1497 /* intensity stereo case */

1498 sf >>= 1;

1499 if (sf < 180) {

1500 lsf_sf_expand(slen, sf, 6, 6, 0);

1501 tindex2 = 3;

1502 } else if (sf < 244) {

1503 lsf_sf_expand(slen, sf - 180, 4, 4, 0);

1504 tindex2 = 4;

1505 } else {

1506 lsf_sf_expand(slen, sf - 244, 3, 0, 0);

1507 tindex2 = 5;

1508 }

1509 } else {

1510 /* normal case */

1511 if (sf < 400) {

1512 lsf_sf_expand(slen, sf, 5, 4, 4);

1513 tindex2 = 0;

1514 } else if (sf < 500) {

1515 lsf_sf_expand(slen, sf - 400, 5, 4, 0);

1516 tindex2 = 1;

1517 } else {

1518 lsf_sf_expand(slen, sf - 500, 3, 0, 0);

1519 tindex2 = 2;

1520 g->preflag = 1;

1521 }

1522 }

1523

1524 j = 0;

1525 for (k = 0; k < 4; k++) {

1526 n = lsf_nsf_table[tindex2][tindex][k];

1527 sl = slen[k];

1528 if (sl) {

1529 for (i = 0; i < n; i++)

1530 g->scale_factors[j++] = get_bits(&s->gb, sl);

1531 } else {

1532 for (i = 0; i < n; i++)

1533 g->scale_factors[j++] = 0;

1534 }

1535 }

1536 /* XXX: should compute exact size */

1537 for (; j < 40; j++)

1538 g->scale_factors[j] = 0;

1539 }

1540

1541 exponents_from_scale_factors(s, g, exponents);

1542

1543 /* read Huffman coded residue */

1544 huffman_decode(s, g, exponents, bits_pos + g->part2_3_length);

1545 } /* ch */

1546

1547 if (s->mode == MPA_JSTEREO)

1548 compute_stereo(s, &s->granules[0][gr], &s->granules[1][gr]);

1549

1550 for (ch = 0; ch < s->nb_channels; ch++) {

1551 g = &s->granules[ch][gr];

1552

1553 reorder_block(s, g);

1554 compute_antialias(s, g);

1555 compute_imdct(s, g, &s->sb_samples[ch][18 * gr][0], s->mdct_buf[ch]);

1556 }

1557 } /* gr */

1558 if (get_bits_count(&s->gb) < 0)

1559 skip_bits_long(&s->gb, -get_bits_count(&s->gb));

1560 return nb_granules * 18;

1561 }

1562

1563 static int mp_decode_frame(MPADecodeContext *s, OUT_INT **samples,

1564 const uint8_t *buf, int buf_size)

1565 {

1566 int i, nb_frames, ch, ret;

1567 OUT_INT *samples_ptr;

1568

1569 init_get_bits(&s->gb, buf + HEADER_SIZE, (buf_size - HEADER_SIZE) * 8);

1570

1571 /* skip error protection field */

1572 if (s->error_protection)

1573 skip_bits(&s->gb, 16);

1574

1575 switch(s->layer) {

1576 case 1:

1577 s->avctx->frame_size = 384;

1578 nb_frames = mp_decode_layer1(s);

1579 break;

1580 case 2:

1581 s->avctx->frame_size = 1152;

1582 nb_frames = mp_decode_layer2(s);

1583 break;

1584 case 3:

1585 s->avctx->frame_size = s->lsf ? 576 : 1152;

1586 default:

1587 nb_frames = mp_decode_layer3(s);

1588

1589 s->last_buf_size=0;

1590 if (s->in_gb.buffer) {

1591 align_get_bits(&s->gb);

1592 i = get_bits_left(&s->gb)>>3;

1593 if (i >= 0 && i <= BACKSTEP_SIZE) {

1594 memmove(s->last_buf, s->gb.buffer + (get_bits_count(&s->gb)>>3), i);

1595 s->last_buf_size=i;

1596 } else

1597 av_log(s->avctx, AV_LOG_ERROR, "invalid old backstep %d\n", i);

1598 s->gb = s->in_gb;

1599 s->in_gb.buffer = NULL;

1600 }

1601

1602 align_get_bits(&s->gb);

1603 av_assert1((get_bits_count(&s->gb) & 7) == 0);

1604 i = get_bits_left(&s->gb) >> 3;

1605

1606 if (i < 0 || i > BACKSTEP_SIZE || nb_frames < 0) {

1607 if (i < 0)

1608 av_log(s->avctx, AV_LOG_ERROR, "invalid new backstep %d\n", i);

1609 i = FFMIN(BACKSTEP_SIZE, buf_size - HEADER_SIZE);

1610 }

1611 av_assert1(i <= buf_size - HEADER_SIZE && i >= 0);

1612 memcpy(s->last_buf + s->last_buf_size, s->gb.buffer + buf_size - HEADER_SIZE - i, i);

1613 s->last_buf_size += i;

1614 }

1615

1616 if(nb_frames < 0)

1617 return nb_frames;

1618

1619 /* get output buffer */

1620 if (!samples) {

1621 av_assert0(s->frame);

1622 s->frame->nb_samples = s->avctx->frame_size;

1623 if ((ret = ff_get_buffer(s->avctx, s->frame, 0)) < 0)

1624 return ret;

1625 samples = (OUT_INT **)s->frame->extended_data;

1626 }

1627

1628 /* apply the synthesis filter */

1629 for (ch = 0; ch < s->nb_channels; ch++) {

1630 int sample_stride;

1631 if (s->avctx->sample_fmt == OUT_FMT_P) {

1632 samples_ptr = samples[ch];

1633 sample_stride = 1;

1634 } else {

1635 samples_ptr = samples[0] + ch;

1636 sample_stride = s->nb_channels;

1637 }

1638 for (i = 0; i < nb_frames; i++) {

1639 RENAME(ff_mpa_synth_filter)(&s->mpadsp, s->synth_buf[ch],

1640 &(s->synth_buf_offset[ch]),

1641 RENAME(ff_mpa_synth_window),

1642 &s->dither_state, samples_ptr,

1643 sample_stride, s->sb_samples[ch][i]);

1644 samples_ptr += 32 * sample_stride;

1645 }

1646 }

1647

1648 return nb_frames * 32 * sizeof(OUT_INT) * s->nb_channels;

1649 }

1650

1651 static int decode_frame(AVCodecContext * avctx, void *data, int *got_frame_ptr,

1652 AVPacket *avpkt)

1653 {

1654 const uint8_t *buf = avpkt->data;

1655 int buf_size = avpkt->size;

1656 MPADecodeContext *s = avctx->priv_data;

1657 uint32_t header;

1658 int ret;

1659

1660 while(buf_size && !*buf){

1661 buf++;

1662 buf_size--;

1663 }

1664

1665 if (buf_size < HEADER_SIZE)

1666 return AVERROR_INVALIDDATA;

1667

1668 header = AV_RB32(buf);

1669 if (header>>8 == AV_RB32("TAG")>>8) {

1670 av_log(avctx, AV_LOG_DEBUG, "discarding ID3 tag\n");

1671 return buf_size;

1672 }

1673 if (ff_mpa_check_header(header) < 0) {

1674 av_log(avctx, AV_LOG_ERROR, "Header missing\n");

1675 return AVERROR_INVALIDDATA;

1676 }

1677

1678 if (avpriv_mpegaudio_decode_header((MPADecodeHeader *)s, header) == 1) {

1679 /* free format: prepare to compute frame size */

1680 s->frame_size = -1;

1681 return AVERROR_INVALIDDATA;

1682 }

1683 /* update codec info */

1684 avctx->channels = s->nb_channels;

1685 avctx->channel_layout = s->nb_channels == 1 ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;

1686 if (!avctx->bit_rate)

1687 avctx->bit_rate = s->bit_rate;

1688

1689 if (s->frame_size <= 0 || s->frame_size > buf_size) {

1690 av_log(avctx, AV_LOG_ERROR, "incomplete frame\n");

1691 return AVERROR_INVALIDDATA;

1692 } else if (s->frame_size < buf_size) {

1693 av_log(avctx, AV_LOG_DEBUG, "incorrect frame size - multiple frames in buffer?\n");

1694 buf_size= s->frame_size;

1695 }

1696

1697 s->frame = data;

1698

1699 ret = mp_decode_frame(s, NULL, buf, buf_size);

1700 if (ret >= 0) {

1701 s->frame->nb_samples = avctx->frame_size;

1702 *got_frame_ptr = 1;

1703 avctx->sample_rate = s->sample_rate;

1704 //FIXME maybe move the other codec info stuff from above here too

1705 } else {

1706 av_log(avctx, AV_LOG_ERROR, "Error while decoding MPEG audio frame.\n");

1707 /* Only return an error if the bad frame makes up the whole packet or

1708 * the error is related to buffer management.

1709 * If there is more data in the packet, just consume the bad frame

1710 * instead of returning an error, which would discard the whole

1711 * packet. */

1712 *got_frame_ptr = 0;

1713 if (buf_size == avpkt->size || ret != AVERROR_INVALIDDATA)

1714 return ret;

1715 }

1716 s->frame_size = 0;

1717 return buf_size;

1718 }

1719

1720 static void mp_flush(MPADecodeContext *ctx)

1721 {

1722 memset(ctx->synth_buf, 0, sizeof(ctx->synth_buf));

1723 memset(ctx->mdct_buf, 0, sizeof(ctx->mdct_buf));

1724 ctx->last_buf_size = 0;

1725 ctx->dither_state = 0;

1726 }

1727

1728 static void flush(AVCodecContext *avctx)

1729 {

1730 mp_flush(avctx->priv_data);

1731 }

1732

1733 #if CONFIG_MP3ADU_DECODER || CONFIG_MP3ADUFLOAT_DECODER

1734 static int decode_frame_adu(AVCodecContext *avctx, void *data,

1735 int *got_frame_ptr, AVPacket *avpkt)

1736 {

1737 const uint8_t *buf = avpkt->data;

1738 int buf_size = avpkt->size;

1739 MPADecodeContext *s = avctx->priv_data;

1740 uint32_t header;

1741 int len, ret;

1742 int av_unused out_size;

1743

1744 len = buf_size;

1745

1746 // Discard too short frames

1747 if (buf_size < HEADER_SIZE) {

1748 av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");

1749 return AVERROR_INVALIDDATA;

1750 }

1751

1752

1753 if (len > MPA_MAX_CODED_FRAME_SIZE)

1754 len = MPA_MAX_CODED_FRAME_SIZE;

1755

1756 // Get header and restore sync word

1757 header = AV_RB32(buf) | 0xffe00000;

1758

1759 if (ff_mpa_check_header(header) < 0) { // Bad header, discard frame

1760 av_log(avctx, AV_LOG_ERROR, "Invalid frame header\n");

1761 return AVERROR_INVALIDDATA;

1762 }

1763

1764 avpriv_mpegaudio_decode_header((MPADecodeHeader *)s, header);

1765 /* update codec info */

1766 avctx->sample_rate = s->sample_rate;

1767 avctx->channels = s->nb_channels;

1768 avctx->channel_layout = s->nb_channels == 1 ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;

1769 if (!avctx->bit_rate)

1770 avctx->bit_rate = s->bit_rate;

1771

1772 s->frame_size = len;

1773

1774 s->frame = data;

1775

1776 ret = mp_decode_frame(s, NULL, buf, buf_size);

1777 if (ret < 0) {

1778 av_log(avctx, AV_LOG_ERROR, "Error while decoding MPEG audio frame.\n");

1779 return ret;

1780 }

1781

1782 *got_frame_ptr = 1;

1783

1784 return buf_size;

1785 }

1786 #endif /* CONFIG_MP3ADU_DECODER || CONFIG_MP3ADUFLOAT_DECODER */

1787

1788 #if CONFIG_MP3ON4_DECODER || CONFIG_MP3ON4FLOAT_DECODER

1789

1790 /**

1791 * Context for MP3On4 decoder

1792 */

1793 typedef struct MP3On4DecodeContext {

1794 int frames; ///< number of mp3 frames per block (number of mp3 decoder instances)

1795 int syncword; ///< syncword patch

1796 const uint8_t *coff; ///< channel offsets in output buffer

1797 MPADecodeContext *mp3decctx[5]; ///< MPADecodeContext for every decoder instance

1798 } MP3On4DecodeContext;

1799

1800 #include "mpeg4audio.h"

1801

1802 /* Next 3 arrays are indexed by channel config number (passed via codecdata) */

1803

1804 /* number of mp3 decoder instances */

1805 static const uint8_t mp3Frames[8] = { 0, 1, 1, 2, 3, 3, 4, 5 };

1806

1807 /* offsets into output buffer, assume output order is FL FR C LFE BL BR SL SR */

1808 static const uint8_t chan_offset[8][5] = {

1809 { 0 },

1810 { 0 }, // C

1811 { 0 }, // FLR

1812 { 2, 0 }, // C FLR

1813 { 2, 0, 3 }, // C FLR BS

1814 { 2, 0, 3 }, // C FLR BLRS

1815 { 2, 0, 4, 3 }, // C FLR BLRS LFE

1816 { 2, 0, 6, 4, 3 }, // C FLR BLRS BLR LFE

1817 };

1818

1819 /* mp3on4 channel layouts */

1820 static const int16_t chan_layout[8] = {

1821 0,

1822 AV_CH_LAYOUT_MONO,

1823 AV_CH_LAYOUT_STEREO,

1824 AV_CH_LAYOUT_SURROUND,

1825 AV_CH_LAYOUT_4POINT0,

1826 AV_CH_LAYOUT_5POINT0,

1827 AV_CH_LAYOUT_5POINT1,

1828 AV_CH_LAYOUT_7POINT1

1829 };

1830

1831 static av_cold int decode_close_mp3on4(AVCodecContext * avctx)

1832 {

1833 MP3On4DecodeContext *s = avctx->priv_data;

1834 int i;

1835

1836 for (i = 0; i < s->frames; i++)

1837 av_freep(&s->mp3decctx[i]);

1838

1839 return 0;

1840 }

1841

1842

1843 static av_cold int decode_init_mp3on4(AVCodecContext * avctx)

1844 {

1845 MP3On4DecodeContext *s = avctx->priv_data;

1846 MPEG4AudioConfig cfg;

1847 int i;

1848

1849 if ((avctx->extradata_size < 2) || !avctx->extradata) {

1850 av_log(avctx, AV_LOG_ERROR, "Codec extradata missing or too short.\n");

1851 return AVERROR_INVALIDDATA;

1852 }

1853

1854 avpriv_mpeg4audio_get_config(&cfg, avctx->extradata,

1855 avctx->extradata_size * 8, 1);

1856 if (!cfg.chan_config || cfg.chan_config > 7) {

1857 av_log(avctx, AV_LOG_ERROR, "Invalid channel config number.\n");

1858 return AVERROR_INVALIDDATA;

1859 }

1860 s->frames = mp3Frames[cfg.chan_config];

1861 s->coff = chan_offset[cfg.chan_config];

1862 avctx->channels = ff_mpeg4audio_channels[cfg.chan_config];

1863 avctx->channel_layout = chan_layout[cfg.chan_config];

1864

1865 if (cfg.sample_rate < 16000)

1866 s->syncword = 0xffe00000;

1867 else

1868 s->syncword = 0xfff00000;

1869

1870 /* Init the first mp3 decoder in standard way, so that all tables get builded

1871 * We replace avctx->priv_data with the context of the first decoder so that

1872 * decode_init() does not have to be changed.

1873 * Other decoders will be initialized here copying data from the first context

1874 */

1875 // Allocate zeroed memory for the first decoder context

1876 s->mp3decctx[0] = av_mallocz(sizeof(MPADecodeContext));

1877 if (!s->mp3decctx[0])

1878 goto alloc_fail;

1879 // Put decoder context in place to make init_decode() happy

1880 avctx->priv_data = s->mp3decctx[0];

1881 decode_init(avctx);

1882 // Restore mp3on4 context pointer

1883 avctx->priv_data = s;

1884 s->mp3decctx[0]->adu_mode = 1; // Set adu mode

1885

1886 /* Create a separate codec/context for each frame (first is already ok).

1887 * Each frame is 1 or 2 channels - up to 5 frames allowed

1888 */

1889 for (i = 1; i < s->frames; i++) {

1890 s->mp3decctx[i] = av_mallocz(sizeof(MPADecodeContext));

1891 if (!s->mp3decctx[i])

1892 goto alloc_fail;

1893 s->mp3decctx[i]->adu_mode = 1;

1894 s->mp3decctx[i]->avctx = avctx;

1895 s->mp3decctx[i]->mpadsp = s->mp3decctx[0]->mpadsp;

1896 }

1897

1898 return 0;

1899 alloc_fail:

1900 decode_close_mp3on4(avctx);

1901 return AVERROR(ENOMEM);

1902 }

1903

1904

1905 static void flush_mp3on4(AVCodecContext *avctx)

1906 {

1907 int i;

1908 MP3On4DecodeContext *s = avctx->priv_data;

1909

1910 for (i = 0; i < s->frames; i++)

1911 mp_flush(s->mp3decctx[i]);

1912 }

1913

1914

1915 static int decode_frame_mp3on4(AVCodecContext *avctx, void *data,

1916 int *got_frame_ptr, AVPacket *avpkt)

1917 {

1918 AVFrame *frame = data;

1919 const uint8_t *buf = avpkt->data;

1920 int buf_size = avpkt->size;

1921 MP3On4DecodeContext *s = avctx->priv_data;

1922 MPADecodeContext *m;

1923 int fsize, len = buf_size, out_size = 0;

1924 uint32_t header;

1925 OUT_INT **out_samples;

1926 OUT_INT *outptr[2];

1927 int fr, ch, ret;

1928

1929 /* get output buffer */

1930 frame->nb_samples = MPA_FRAME_SIZE;

1931 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)

1932 return ret;

1933 out_samples = (OUT_INT **)frame->extended_data;

1934

1935 // Discard too short frames

1936 if (buf_size < HEADER_SIZE)

1937 return AVERROR_INVALIDDATA;

1938

1939 avctx->bit_rate = 0;

1940

1941 ch = 0;

1942 for (fr = 0; fr < s->frames; fr++) {

1943 fsize = AV_RB16(buf) >> 4;

1944 fsize = FFMIN3(fsize, len, MPA_MAX_CODED_FRAME_SIZE);

1945 m = s->mp3decctx[fr];

1946 av_assert1(m);

1947

1948 if (fsize < HEADER_SIZE) {

1949 av_log(avctx, AV_LOG_ERROR, "Frame size smaller than header size\n");

1950 return AVERROR_INVALIDDATA;

1951 }

1952 header = (AV_RB32(buf) & 0x000fffff) | s->syncword; // patch header

1953

1954 if (ff_mpa_check_header(header) < 0) {

1955 av_log(avctx, AV_LOG_ERROR, "Bad header, discard block\n");

1956 return AVERROR_INVALIDDATA;

1957 }

1958

1959 avpriv_mpegaudio_decode_header((MPADecodeHeader *)m, header);

1960

1961 if (ch + m->nb_channels > avctx->channels ||

1962 s->coff[fr] + m->nb_channels > avctx->channels) {

1963 av_log(avctx, AV_LOG_ERROR, "frame channel count exceeds codec "

1964 "channel count\n");

1965 return AVERROR_INVALIDDATA;

1966 }

1967 ch += m->nb_channels;

1968

1969 outptr[0] = out_samples[s->coff[fr]];

1970 if (m->nb_channels > 1)

1971 outptr[1] = out_samples[s->coff[fr] + 1];

1972

1973 if ((ret = mp_decode_frame(m, outptr, buf, fsize)) < 0) {

1974 av_log(avctx, AV_LOG_ERROR, "failed to decode channel %d\n", ch);

1975 memset(outptr[0], 0, MPA_FRAME_SIZE*sizeof(OUT_INT));

1976 if (m->nb_channels > 1)

1977 memset(outptr[1], 0, MPA_FRAME_SIZE*sizeof(OUT_INT));

1978 ret = m->nb_channels * MPA_FRAME_SIZE*sizeof(OUT_INT);

1979 }

1980

1981 out_size += ret;

1982 buf += fsize;

1983 len -= fsize;

1984

1985 avctx->bit_rate += m->bit_rate;

1986 }

1987 if (ch != avctx->channels) {

1988 av_log(avctx, AV_LOG_ERROR, "failed to decode all channels\n");

1989 return AVERROR_INVALIDDATA;

1990 }

1991

1992 /* update codec info */

1993 avctx->sample_rate = s->mp3decctx[0]->sample_rate;

1994

1995 frame->nb_samples = out_size / (avctx->channels * sizeof(OUT_INT));

1996 *got_frame_ptr = 1;

1997

1998 return buf_size;

1999 }

2000 #endif /* CONFIG_MP3ON4_DECODER || CONFIG_MP3ON4FLOAT_DECODER */

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