mpegaudiodec.c 76.6 KB
Newer Older
Fabrice Bellard's avatar
Fabrice Bellard committed
1 2
/*
 * MPEG Audio decoder
3
 * Copyright (c) 2001, 2002 Fabrice Bellard
Fabrice Bellard's avatar
Fabrice Bellard committed
4
 *
5 6 7
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
8 9
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
Fabrice Bellard's avatar
Fabrice Bellard committed
11
 *
12
 * FFmpeg is distributed in the hope that it will be useful,
Fabrice Bellard's avatar
Fabrice Bellard committed
13
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 15
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
Fabrice Bellard's avatar
Fabrice Bellard committed
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
Fabrice Bellard's avatar
Fabrice Bellard committed
20
 */
Michael Niedermayer's avatar
Michael Niedermayer committed
21 22

/**
23
 * @file libavcodec/mpegaudiodec.c
Michael Niedermayer's avatar
Michael Niedermayer committed
24
 * MPEG Audio decoder.
25
 */
Michael Niedermayer's avatar
Michael Niedermayer committed
26

Fabrice Bellard's avatar
Fabrice Bellard committed
27
#include "avcodec.h"
28
#include "get_bits.h"
29
#include "dsputil.h"
Fabrice Bellard's avatar
Fabrice Bellard committed
30 31

/*
32 33 34
 * TODO:
 *  - in low precision mode, use more 16 bit multiplies in synth filter
 *  - test lsf / mpeg25 extensively.
Fabrice Bellard's avatar
Fabrice Bellard committed
35 36
 */

Roberto Togni's avatar
Roberto Togni committed
37
#include "mpegaudio.h"
38
#include "mpegaudiodecheader.h"
39

Luca Barbato's avatar
Luca Barbato committed
40 41
#include "mathops.h"

42 43 44 45
/* WARNING: only correct for posititive numbers */
#define FIXR(a)   ((int)((a) * FRAC_ONE + 0.5))
#define FRAC_RND(a) (((a) + (FRAC_ONE/2)) >> FRAC_BITS)

46 47
#define FIXHR(a) ((int)((a) * (1LL<<32) + 0.5))

48 49
/****************/

Fabrice Bellard's avatar
Fabrice Bellard committed
50 51
#define HEADER_SIZE 4

52
#include "mpegaudiodata.h"
53 54
#include "mpegaudiodectab.h"

55 56 57
static void compute_antialias_integer(MPADecodeContext *s, GranuleDef *g);
static void compute_antialias_float(MPADecodeContext *s, GranuleDef *g);

58
/* vlc structure for decoding layer 3 huffman tables */
59
static VLC huff_vlc[16];
60 61 62 63 64 65 66 67
static VLC_TYPE huff_vlc_tables[
  0+128+128+128+130+128+154+166+
  142+204+190+170+542+460+662+414
  ][2];
static const int huff_vlc_tables_sizes[16] = {
  0, 128, 128, 128, 130, 128, 154, 166,
  142, 204, 190, 170, 542, 460, 662, 414
};
68
static VLC huff_quad_vlc[2];
69 70 71 72
static VLC_TYPE huff_quad_vlc_tables[128+16][2];
static const int huff_quad_vlc_tables_sizes[2] = {
  128, 16
};
73
/* computed from band_size_long */
74
static uint16_t band_index_long[9][23];
75
#include "mpegaudio_tablegen.h"
76
/* intensity stereo coef table */
77 78
static int32_t is_table[2][16];
static int32_t is_table_lsf[2][2][16];
79 80
static int32_t csa_table[8][4];
static float csa_table_float[8][4];
81
static int32_t mdct_win[8][36];
82 83

/* lower 2 bits: modulo 3, higher bits: shift */
84
static uint16_t scale_factor_modshift[64];
85
/* [i][j]:  2^(-j/3) * FRAC_ONE * 2^(i+2) / (2^(i+2) - 1) */
86
static int32_t scale_factor_mult[15][3];
87 88 89 90 91
/* mult table for layer 2 group quantization */

#define SCALE_GEN(v) \
{ FIXR(1.0 * (v)), FIXR(0.7937005259 * (v)), FIXR(0.6299605249 * (v)) }

Michael Niedermayer's avatar
Michael Niedermayer committed
92
static const int32_t scale_factor_mult2[3][3] = {
93 94 95
    SCALE_GEN(4.0 / 3.0), /* 3 steps */
    SCALE_GEN(4.0 / 5.0), /* 5 steps */
    SCALE_GEN(4.0 / 9.0), /* 9 steps */
96 97
};

98
DECLARE_ALIGNED_16(MPA_INT, ff_mpa_synth_window[512]);
99

100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161
/**
 * Convert region offsets to region sizes and truncate
 * size to big_values.
 */
void ff_region_offset2size(GranuleDef *g){
    int i, k, j=0;
    g->region_size[2] = (576 / 2);
    for(i=0;i<3;i++) {
        k = FFMIN(g->region_size[i], g->big_values);
        g->region_size[i] = k - j;
        j = k;
    }
}

void ff_init_short_region(MPADecodeContext *s, GranuleDef *g){
    if (g->block_type == 2)
        g->region_size[0] = (36 / 2);
    else {
        if (s->sample_rate_index <= 2)
            g->region_size[0] = (36 / 2);
        else if (s->sample_rate_index != 8)
            g->region_size[0] = (54 / 2);
        else
            g->region_size[0] = (108 / 2);
    }
    g->region_size[1] = (576 / 2);
}

void ff_init_long_region(MPADecodeContext *s, GranuleDef *g, int ra1, int ra2){
    int l;
    g->region_size[0] =
        band_index_long[s->sample_rate_index][ra1 + 1] >> 1;
    /* should not overflow */
    l = FFMIN(ra1 + ra2 + 2, 22);
    g->region_size[1] =
        band_index_long[s->sample_rate_index][l] >> 1;
}

void ff_compute_band_indexes(MPADecodeContext *s, GranuleDef *g){
    if (g->block_type == 2) {
        if (g->switch_point) {
            /* if switched mode, we handle the 36 first samples as
                long blocks.  For 8000Hz, we handle the 48 first
                exponents as long blocks (XXX: check this!) */
            if (s->sample_rate_index <= 2)
                g->long_end = 8;
            else if (s->sample_rate_index != 8)
                g->long_end = 6;
            else
                g->long_end = 4; /* 8000 Hz */

            g->short_start = 2 + (s->sample_rate_index != 8);
        } else {
            g->long_end = 0;
            g->short_start = 0;
        }
    } else {
        g->short_start = 13;
        g->long_end = 22;
    }
}

162 163 164 165 166
/* layer 1 unscaling */
/* n = number of bits of the mantissa minus 1 */
static inline int l1_unscale(int n, int mant, int scale_factor)
{
    int shift, mod;
167
    int64_t val;
168 169 170 171 172 173

    shift = scale_factor_modshift[scale_factor];
    mod = shift & 3;
    shift >>= 2;
    val = MUL64(mant + (-1 << n) + 1, scale_factor_mult[n-1][mod]);
    shift += n;
174 175
    /* NOTE: at this point, 1 <= shift >= 21 + 15 */
    return (int)((val + (1LL << (shift - 1))) >> shift);
176 177 178 179 180 181 182 183 184
}

static inline int l2_unscale_group(int steps, int mant, int scale_factor)
{
    int shift, mod, val;

    shift = scale_factor_modshift[scale_factor];
    mod = shift & 3;
    shift >>= 2;
185 186 187 188 189 190

    val = (mant - (steps >> 1)) * scale_factor_mult2[steps >> 2][mod];
    /* NOTE: at this point, 0 <= shift <= 21 */
    if (shift > 0)
        val = (val + (1 << (shift - 1))) >> shift;
    return val;
191 192 193 194 195 196 197 198
}

/* compute value^(4/3) * 2^(exponent/4). It normalized to FRAC_BITS */
static inline int l3_unscale(int value, int exponent)
{
    unsigned int m;
    int e;

199 200 201 202
    e = table_4_3_exp  [4*value + (exponent&3)];
    m = table_4_3_value[4*value + (exponent&3)];
    e -= (exponent >> 2);
    assert(e>=1);
203
    if (e > 31)
204
        return 0;
205
    m = (m + (1 << (e-1))) >> e;
206

207 208 209
    return m;
}

210 211 212 213 214 215
/* all integer n^(4/3) computation code */
#define DEV_ORDER 13

#define POW_FRAC_BITS 24
#define POW_FRAC_ONE    (1 << POW_FRAC_BITS)
#define POW_FIX(a)   ((int)((a) * POW_FRAC_ONE))
216
#define POW_MULL(a,b) (((int64_t)(a) * (int64_t)(b)) >> POW_FRAC_BITS)
217 218 219

static int dev_4_3_coefs[DEV_ORDER];

220
#if 0 /* unused */
221 222 223 224 225
static int pow_mult3[3] = {
    POW_FIX(1.0),
    POW_FIX(1.25992104989487316476),
    POW_FIX(1.58740105196819947474),
};
226
#endif
227

228
static av_cold void int_pow_init(void)
229 230 231 232 233 234 235 236 237 238
{
    int i, a;

    a = POW_FIX(1.0);
    for(i=0;i<DEV_ORDER;i++) {
        a = POW_MULL(a, POW_FIX(4.0 / 3.0) - i * POW_FIX(1.0)) / (i + 1);
        dev_4_3_coefs[i] = a;
    }
}

239
#if 0 /* unused, remove? */
240 241 242 243 244
/* return the mantissa and the binary exponent */
static int int_pow(int i, int *exp_ptr)
{
    int e, er, eq, j;
    int a, a1;
245

246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271
    /* renormalize */
    a = i;
    e = POW_FRAC_BITS;
    while (a < (1 << (POW_FRAC_BITS - 1))) {
        a = a << 1;
        e--;
    }
    a -= (1 << POW_FRAC_BITS);
    a1 = 0;
    for(j = DEV_ORDER - 1; j >= 0; j--)
        a1 = POW_MULL(a, dev_4_3_coefs[j] + a1);
    a = (1 << POW_FRAC_BITS) + a1;
    /* exponent compute (exact) */
    e = e * 4;
    er = e % 3;
    eq = e / 3;
    a = POW_MULL(a, pow_mult3[er]);
    while (a >= 2 * POW_FRAC_ONE) {
        a = a >> 1;
        eq++;
    }
    /* convert to float */
    while (a < POW_FRAC_ONE) {
        a = a << 1;
        eq--;
    }
272
    /* now POW_FRAC_ONE <= a < 2 * POW_FRAC_ONE */
273
#if POW_FRAC_BITS > FRAC_BITS
274 275 276 277 278 279 280
    a = (a + (1 << (POW_FRAC_BITS - FRAC_BITS - 1))) >> (POW_FRAC_BITS - FRAC_BITS);
    /* correct overflow */
    if (a >= 2 * (1 << FRAC_BITS)) {
        a = a >> 1;
        eq++;
    }
#endif
281 282 283
    *exp_ptr = eq;
    return a;
}
284
#endif
Fabrice Bellard's avatar
Fabrice Bellard committed
285

286
static av_cold int decode_init(AVCodecContext * avctx)
Fabrice Bellard's avatar
Fabrice Bellard committed
287 288
{
    MPADecodeContext *s = avctx->priv_data;
289
    static int init=0;
290
    int i, j, k;
Fabrice Bellard's avatar
Fabrice Bellard committed
291

292 293
    s->avctx = avctx;

294
    avctx->sample_fmt= OUT_FMT;
295
    s->error_recognition= avctx->error_recognition;
296

Michael Niedermayer's avatar
Michael Niedermayer committed
297
    if(avctx->antialias_algo != FF_AA_FLOAT)
Michael Niedermayer's avatar
Michael Niedermayer committed
298 299 300 301
        s->compute_antialias= compute_antialias_integer;
    else
        s->compute_antialias= compute_antialias_float;

302
    if (!init && !avctx->parse_only) {
303 304
        int offset;

305 306 307 308
        /* scale factors table for layer 1/2 */
        for(i=0;i<64;i++) {
            int shift, mod;
            /* 1.0 (i = 3) is normalized to 2 ^ FRAC_BITS */
309
            shift = (i / 3);
310 311 312 313 314 315 316 317
            mod = i % 3;
            scale_factor_modshift[i] = mod | (shift << 2);
        }

        /* scale factor multiply for layer 1 */
        for(i=0;i<15;i++) {
            int n, norm;
            n = i + 2;
318
            norm = ((INT64_C(1) << n) * FRAC_ONE) / ((1 << n) - 1);
319 320 321
            scale_factor_mult[i][0] = MULL(FIXR(1.0 * 2.0), norm, FRAC_BITS);
            scale_factor_mult[i][1] = MULL(FIXR(0.7937005259 * 2.0), norm, FRAC_BITS);
            scale_factor_mult[i][2] = MULL(FIXR(0.6299605249 * 2.0), norm, FRAC_BITS);
322
            dprintf(avctx, "%d: norm=%x s=%x %x %x\n",
323
                    i, norm,
324 325 326 327
                    scale_factor_mult[i][0],
                    scale_factor_mult[i][1],
                    scale_factor_mult[i][2]);
        }
328

329
        ff_mpa_synth_init(ff_mpa_synth_window);
330

331
        /* huffman decode tables */
332
        offset = 0;
333 334
        for(i=1;i<16;i++) {
            const HuffTable *h = &mpa_huff_tables[i];
335
            int xsize, x, y;
Michael Niedermayer's avatar
Michael Niedermayer committed
336 337
            uint8_t  tmp_bits [512];
            uint16_t tmp_codes[512];
Michael Niedermayer's avatar
Michael Niedermayer committed
338 339 340

            memset(tmp_bits , 0, sizeof(tmp_bits ));
            memset(tmp_codes, 0, sizeof(tmp_codes));
341 342

            xsize = h->xsize;
343

344 345
            j = 0;
            for(x=0;x<xsize;x++) {
Michael Niedermayer's avatar
Michael Niedermayer committed
346
                for(y=0;y<xsize;y++){
Michael Niedermayer's avatar
Michael Niedermayer committed
347 348
                    tmp_bits [(x << 5) | y | ((x&&y)<<4)]= h->bits [j  ];
                    tmp_codes[(x << 5) | y | ((x&&y)<<4)]= h->codes[j++];
Michael Niedermayer's avatar
Michael Niedermayer committed
349
                }
350
            }
Michael Niedermayer's avatar
Michael Niedermayer committed
351 352

            /* XXX: fail test */
353 354
            huff_vlc[i].table = huff_vlc_tables+offset;
            huff_vlc[i].table_allocated = huff_vlc_tables_sizes[i];
Michael Niedermayer's avatar
Michael Niedermayer committed
355
            init_vlc(&huff_vlc[i], 7, 512,
356 357 358
                     tmp_bits, 1, 1, tmp_codes, 2, 2,
                     INIT_VLC_USE_NEW_STATIC);
            offset += huff_vlc_tables_sizes[i];
359
        }
360
        assert(offset == FF_ARRAY_ELEMS(huff_vlc_tables));
361 362

        offset = 0;
363
        for(i=0;i<2;i++) {
364 365
            huff_quad_vlc[i].table = huff_quad_vlc_tables+offset;
            huff_quad_vlc[i].table_allocated = huff_quad_vlc_tables_sizes[i];
366
            init_vlc(&huff_quad_vlc[i], i == 0 ? 7 : 4, 16,
367 368 369
                     mpa_quad_bits[i], 1, 1, mpa_quad_codes[i], 1, 1,
                     INIT_VLC_USE_NEW_STATIC);
            offset += huff_quad_vlc_tables_sizes[i];
370
        }
371
        assert(offset == FF_ARRAY_ELEMS(huff_quad_vlc_tables));
372 373 374 375 376 377 378 379 380 381

        for(i=0;i<9;i++) {
            k = 0;
            for(j=0;j<22;j++) {
                band_index_long[i][j] = k;
                k += band_size_long[i][j];
            }
            band_index_long[i][22] = k;
        }

382
        /* compute n ^ (4/3) and store it in mantissa/exp format */
383

384
        int_pow_init();
385
        mpegaudio_tableinit();
386

387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412
        for(i=0;i<7;i++) {
            float f;
            int v;
            if (i != 6) {
                f = tan((double)i * M_PI / 12.0);
                v = FIXR(f / (1.0 + f));
            } else {
                v = FIXR(1.0);
            }
            is_table[0][i] = v;
            is_table[1][6 - i] = v;
        }
        /* invalid values */
        for(i=7;i<16;i++)
            is_table[0][i] = is_table[1][i] = 0.0;

        for(i=0;i<16;i++) {
            double f;
            int e, k;

            for(j=0;j<2;j++) {
                e = -(j + 1) * ((i + 1) >> 1);
                f = pow(2.0, e / 4.0);
                k = i & 1;
                is_table_lsf[j][k ^ 1][i] = FIXR(f);
                is_table_lsf[j][k][i] = FIXR(1.0);
413
                dprintf(avctx, "is_table_lsf %d %d: %x %x\n",
414 415 416 417 418 419 420 421 422
                        i, j, is_table_lsf[j][0][i], is_table_lsf[j][1][i]);
            }
        }

        for(i=0;i<8;i++) {
            float ci, cs, ca;
            ci = ci_table[i];
            cs = 1.0 / sqrt(1.0 + ci * ci);
            ca = cs * ci;
Michael Niedermayer's avatar
Michael Niedermayer committed
423 424 425
            csa_table[i][0] = FIXHR(cs/4);
            csa_table[i][1] = FIXHR(ca/4);
            csa_table[i][2] = FIXHR(ca/4) + FIXHR(cs/4);
426
            csa_table[i][3] = FIXHR(ca/4) - FIXHR(cs/4);
427 428 429
            csa_table_float[i][0] = cs;
            csa_table_float[i][1] = ca;
            csa_table_float[i][2] = ca + cs;
430
            csa_table_float[i][3] = ca - cs;
431 432 433 434
        }

        /* compute mdct windows */
        for(i=0;i<36;i++) {
435 436
            for(j=0; j<4; j++){
                double d;
437

Michael Niedermayer's avatar
Michael Niedermayer committed
438 439
                if(j==2 && i%3 != 1)
                    continue;
440

441 442 443 444 445 446 447 448 449 450 451
                d= sin(M_PI * (i + 0.5) / 36.0);
                if(j==1){
                    if     (i>=30) d= 0;
                    else if(i>=24) d= sin(M_PI * (i - 18 + 0.5) / 12.0);
                    else if(i>=18) d= 1;
                }else if(j==3){
                    if     (i<  6) d= 0;
                    else if(i< 12) d= sin(M_PI * (i -  6 + 0.5) / 12.0);
                    else if(i< 18) d= 1;
                }
                //merge last stage of imdct into the window coefficients
Michael Niedermayer's avatar
Michael Niedermayer committed
452 453 454 455 456 457
                d*= 0.5 / cos(M_PI*(2*i + 19)/72);

                if(j==2)
                    mdct_win[j][i/3] = FIXHR((d / (1<<5)));
                else
                    mdct_win[j][i  ] = FIXHR((d / (1<<5)));
458
            }
459 460 461 462 463 464 465 466 467 468 469
        }

        /* NOTE: we do frequency inversion adter the MDCT by changing
           the sign of the right window coefs */
        for(j=0;j<4;j++) {
            for(i=0;i<36;i+=2) {
                mdct_win[j + 4][i] = mdct_win[j][i];
                mdct_win[j + 4][i + 1] = -mdct_win[j][i + 1];
            }
        }

Fabrice Bellard's avatar
Fabrice Bellard committed
470 471 472
        init = 1;
    }

Roberto Togni's avatar
Roberto Togni committed
473 474
    if (avctx->codec_id == CODEC_ID_MP3ADU)
        s->adu_mode = 1;
Fabrice Bellard's avatar
Fabrice Bellard committed
475 476 477
    return 0;
}

478
/* tab[i][j] = 1.0 / (2.0 * cos(pi*(2*k+1) / 2^(6 - j))) */
479 480 481

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

482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516
#define COS0_0  FIXHR(0.50060299823519630134/2)
#define COS0_1  FIXHR(0.50547095989754365998/2)
#define COS0_2  FIXHR(0.51544730992262454697/2)
#define COS0_3  FIXHR(0.53104259108978417447/2)
#define COS0_4  FIXHR(0.55310389603444452782/2)
#define COS0_5  FIXHR(0.58293496820613387367/2)
#define COS0_6  FIXHR(0.62250412303566481615/2)
#define COS0_7  FIXHR(0.67480834145500574602/2)
#define COS0_8  FIXHR(0.74453627100229844977/2)
#define COS0_9  FIXHR(0.83934964541552703873/2)
#define COS0_10 FIXHR(0.97256823786196069369/2)
#define COS0_11 FIXHR(1.16943993343288495515/4)
#define COS0_12 FIXHR(1.48416461631416627724/4)
#define COS0_13 FIXHR(2.05778100995341155085/8)
#define COS0_14 FIXHR(3.40760841846871878570/8)
#define COS0_15 FIXHR(10.19000812354805681150/32)

#define COS1_0 FIXHR(0.50241928618815570551/2)
#define COS1_1 FIXHR(0.52249861493968888062/2)
#define COS1_2 FIXHR(0.56694403481635770368/2)
#define COS1_3 FIXHR(0.64682178335999012954/2)
#define COS1_4 FIXHR(0.78815462345125022473/2)
#define COS1_5 FIXHR(1.06067768599034747134/4)
#define COS1_6 FIXHR(1.72244709823833392782/4)
#define COS1_7 FIXHR(5.10114861868916385802/16)

#define COS2_0 FIXHR(0.50979557910415916894/2)
#define COS2_1 FIXHR(0.60134488693504528054/2)
#define COS2_2 FIXHR(0.89997622313641570463/2)
#define COS2_3 FIXHR(2.56291544774150617881/8)

#define COS3_0 FIXHR(0.54119610014619698439/2)
#define COS3_1 FIXHR(1.30656296487637652785/4)

#define COS4_0 FIXHR(0.70710678118654752439/2)
517 518

/* butterfly operator */
519
#define BF(a, b, c, s)\
520 521 522 523
{\
    tmp0 = tab[a] + tab[b];\
    tmp1 = tab[a] - tab[b];\
    tab[a] = tmp0;\
524
    tab[b] = MULH(tmp1<<(s), c);\
525 526 527 528
}

#define BF1(a, b, c, d)\
{\
529 530
    BF(a, b, COS4_0, 1);\
    BF(c, d,-COS4_0, 1);\
531 532 533 534 535
    tab[c] += tab[d];\
}

#define BF2(a, b, c, d)\
{\
536 537
    BF(a, b, COS4_0, 1);\
    BF(c, d,-COS4_0, 1);\
538 539 540 541 542 543 544 545 546
    tab[c] += tab[d];\
    tab[a] += tab[c];\
    tab[c] += tab[b];\
    tab[b] += tab[d];\
}

#define ADD(a, b) tab[a] += tab[b]

/* DCT32 without 1/sqrt(2) coef zero scaling. */
547
static void dct32(int32_t *out, int32_t *tab)
548 549 550 551
{
    int tmp0, tmp1;

    /* pass 1 */
552 553
    BF( 0, 31, COS0_0 , 1);
    BF(15, 16, COS0_15, 5);
554
    /* pass 2 */
555 556
    BF( 0, 15, COS1_0 , 1);
    BF(16, 31,-COS1_0 , 1);
557
    /* pass 1 */
558 559
    BF( 7, 24, COS0_7 , 1);
    BF( 8, 23, COS0_8 , 1);
560
    /* pass 2 */
561 562
    BF( 7,  8, COS1_7 , 4);
    BF(23, 24,-COS1_7 , 4);
563
    /* pass 3 */
564 565 566 567
    BF( 0,  7, COS2_0 , 1);
    BF( 8, 15,-COS2_0 , 1);
    BF(16, 23, COS2_0 , 1);
    BF(24, 31,-COS2_0 , 1);
568
    /* pass 1 */
569 570
    BF( 3, 28, COS0_3 , 1);
    BF(12, 19, COS0_12, 2);
571
    /* pass 2 */
572 573
    BF( 3, 12, COS1_3 , 1);
    BF(19, 28,-COS1_3 , 1);
574
    /* pass 1 */
575 576
    BF( 4, 27, COS0_4 , 1);
    BF(11, 20, COS0_11, 2);
577
    /* pass 2 */
578 579
    BF( 4, 11, COS1_4 , 1);
    BF(20, 27,-COS1_4 , 1);
580
    /* pass 3 */
581 582 583 584
    BF( 3,  4, COS2_3 , 3);
    BF(11, 12,-COS2_3 , 3);
    BF(19, 20, COS2_3 , 3);
    BF(27, 28,-COS2_3 , 3);
585
    /* pass 4 */
586 587 588 589 590 591 592 593
    BF( 0,  3, COS3_0 , 1);
    BF( 4,  7,-COS3_0 , 1);
    BF( 8, 11, COS3_0 , 1);
    BF(12, 15,-COS3_0 , 1);
    BF(16, 19, COS3_0 , 1);
    BF(20, 23,-COS3_0 , 1);
    BF(24, 27, COS3_0 , 1);
    BF(28, 31,-COS3_0 , 1);
594

595 596 597


    /* pass 1 */
598 599
    BF( 1, 30, COS0_1 , 1);
    BF(14, 17, COS0_14, 3);
600
    /* pass 2 */
601 602
    BF( 1, 14, COS1_1 , 1);
    BF(17, 30,-COS1_1 , 1);
603
    /* pass 1 */
604 605
    BF( 6, 25, COS0_6 , 1);
    BF( 9, 22, COS0_9 , 1);
606
    /* pass 2 */
607 608
    BF( 6,  9, COS1_6 , 2);
    BF(22, 25,-COS1_6 , 2);
609
    /* pass 3 */
610 611 612 613
    BF( 1,  6, COS2_1 , 1);
    BF( 9, 14,-COS2_1 , 1);
    BF(17, 22, COS2_1 , 1);
    BF(25, 30,-COS2_1 , 1);
614

615
    /* pass 1 */
616 617
    BF( 2, 29, COS0_2 , 1);
    BF(13, 18, COS0_13, 3);
618
    /* pass 2 */
619 620
    BF( 2, 13, COS1_2 , 1);
    BF(18, 29,-COS1_2 , 1);
621
    /* pass 1 */
622 623
    BF( 5, 26, COS0_5 , 1);
    BF(10, 21, COS0_10, 1);
624
    /* pass 2 */
625 626
    BF( 5, 10, COS1_5 , 2);
    BF(21, 26,-COS1_5 , 2);
627
    /* pass 3 */
628 629 630 631
    BF( 2,  5, COS2_2 , 1);
    BF(10, 13,-COS2_2 , 1);
    BF(18, 21, COS2_2 , 1);
    BF(26, 29,-COS2_2 , 1);
632
    /* pass 4 */
633 634 635 636 637 638 639 640
    BF( 1,  2, COS3_1 , 2);
    BF( 5,  6,-COS3_1 , 2);
    BF( 9, 10, COS3_1 , 2);
    BF(13, 14,-COS3_1 , 2);
    BF(17, 18, COS3_1 , 2);
    BF(21, 22,-COS3_1 , 2);
    BF(25, 26, COS3_1 , 2);
    BF(29, 30,-COS3_1 , 2);
641

642
    /* pass 5 */
643 644 645
    BF1( 0,  1,  2,  3);
    BF2( 4,  5,  6,  7);
    BF1( 8,  9, 10, 11);
646 647 648 649 650
    BF2(12, 13, 14, 15);
    BF1(16, 17, 18, 19);
    BF2(20, 21, 22, 23);
    BF1(24, 25, 26, 27);
    BF2(28, 29, 30, 31);
651

652
    /* pass 6 */
653

654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677
    ADD( 8, 12);
    ADD(12, 10);
    ADD(10, 14);
    ADD(14,  9);
    ADD( 9, 13);
    ADD(13, 11);
    ADD(11, 15);

    out[ 0] = tab[0];
    out[16] = tab[1];
    out[ 8] = tab[2];
    out[24] = tab[3];
    out[ 4] = tab[4];
    out[20] = tab[5];
    out[12] = tab[6];
    out[28] = tab[7];
    out[ 2] = tab[8];
    out[18] = tab[9];
    out[10] = tab[10];
    out[26] = tab[11];
    out[ 6] = tab[12];
    out[22] = tab[13];
    out[14] = tab[14];
    out[30] = tab[15];
678

679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706
    ADD(24, 28);
    ADD(28, 26);
    ADD(26, 30);
    ADD(30, 25);
    ADD(25, 29);
    ADD(29, 27);
    ADD(27, 31);

    out[ 1] = tab[16] + tab[24];
    out[17] = tab[17] + tab[25];
    out[ 9] = tab[18] + tab[26];
    out[25] = tab[19] + tab[27];
    out[ 5] = tab[20] + tab[28];
    out[21] = tab[21] + tab[29];
    out[13] = tab[22] + tab[30];
    out[29] = tab[23] + tab[31];
    out[ 3] = tab[24] + tab[20];
    out[19] = tab[25] + tab[21];
    out[11] = tab[26] + tab[22];
    out[27] = tab[27] + tab[23];
    out[ 7] = tab[28] + tab[18];
    out[23] = tab[29] + tab[19];
    out[15] = tab[30] + tab[17];
    out[31] = tab[31];
}

#if FRAC_BITS <= 15

707
static inline int round_sample(int *sum)
708 709
{
    int sum1;
710 711
    sum1 = (*sum) >> OUT_SHIFT;
    *sum &= (1<<OUT_SHIFT)-1;
712
    return av_clip(sum1, OUT_MIN, OUT_MAX);
713 714
}

Luca Barbato's avatar
Luca Barbato committed
715 716
/* signed 16x16 -> 32 multiply add accumulate */
#define MACS(rt, ra, rb) MAC16(rt, ra, rb)
Siarhei Siamashka's avatar
Siarhei Siamashka committed
717

Luca Barbato's avatar
Luca Barbato committed
718 719
/* signed 16x16 -> 32 multiply */
#define MULS(ra, rb) MUL16(ra, rb)
720

721 722
#define MLSS(rt, ra, rb) MLS16(rt, ra, rb)

723 724
#else

725
static inline int round_sample(int64_t *sum)
726 727
{
    int sum1;
728 729
    sum1 = (int)((*sum) >> OUT_SHIFT);
    *sum &= (1<<OUT_SHIFT)-1;
730
    return av_clip(sum1, OUT_MIN, OUT_MAX);
731 732
}

733
#   define MULS(ra, rb) MUL64(ra, rb)
734 735
#   define MACS(rt, ra, rb) MAC64(rt, ra, rb)
#   define MLSS(rt, ra, rb) MLS64(rt, ra, rb)
736 737
#endif

738 739
#define SUM8(op, sum, w, p)               \
{                                         \
740 741 742 743 744 745 746 747
    op(sum, (w)[0 * 64], (p)[0 * 64]);    \
    op(sum, (w)[1 * 64], (p)[1 * 64]);    \
    op(sum, (w)[2 * 64], (p)[2 * 64]);    \
    op(sum, (w)[3 * 64], (p)[3 * 64]);    \
    op(sum, (w)[4 * 64], (p)[4 * 64]);    \
    op(sum, (w)[5 * 64], (p)[5 * 64]);    \
    op(sum, (w)[6 * 64], (p)[6 * 64]);    \
    op(sum, (w)[7 * 64], (p)[7 * 64]);    \
748 749 750 751 752 753
}

#define SUM8P2(sum1, op1, sum2, op2, w1, w2, p) \
{                                               \
    int tmp;\
    tmp = p[0 * 64];\
754 755
    op1(sum1, (w1)[0 * 64], tmp);\
    op2(sum2, (w2)[0 * 64], tmp);\
756
    tmp = p[1 * 64];\
757 758
    op1(sum1, (w1)[1 * 64], tmp);\
    op2(sum2, (w2)[1 * 64], tmp);\
759
    tmp = p[2 * 64];\
760 761
    op1(sum1, (w1)[2 * 64], tmp);\
    op2(sum2, (w2)[2 * 64], tmp);\
762
    tmp = p[3 * 64];\
763 764
    op1(sum1, (w1)[3 * 64], tmp);\
    op2(sum2, (w2)[3 * 64], tmp);\
765
    tmp = p[4 * 64];\
766 767
    op1(sum1, (w1)[4 * 64], tmp);\
    op2(sum2, (w2)[4 * 64], tmp);\
768
    tmp = p[5 * 64];\
769 770
    op1(sum1, (w1)[5 * 64], tmp);\
    op2(sum2, (w2)[5 * 64], tmp);\
771
    tmp = p[6 * 64];\
772 773
    op1(sum1, (w1)[6 * 64], tmp);\
    op2(sum2, (w2)[6 * 64], tmp);\
774
    tmp = p[7 * 64];\
775 776
    op1(sum1, (w1)[7 * 64], tmp);\
    op2(sum2, (w2)[7 * 64], tmp);\
777 778
}

779
void av_cold ff_mpa_synth_init(MPA_INT *window)
780 781 782 783 784 785
{
    int i;

    /* max = 18760, max sum over all 16 coefs : 44736 */
    for(i=0;i<257;i++) {
        int v;
786
        v = ff_mpa_enwindow[i];
787 788 789 790 791 792 793 794
#if WFRAC_BITS < 16
        v = (v + (1 << (16 - WFRAC_BITS - 1))) >> (16 - WFRAC_BITS);
#endif
        window[i] = v;
        if ((i & 63) != 0)
            v = -v;
        if (i != 0)
            window[512 - i] = v;
795
    }
796
}
797 798 799 800

/* 32 sub band synthesis filter. Input: 32 sub band samples, Output:
   32 samples. */
/* XXX: optimize by avoiding ring buffer usage */
801
void ff_mpa_synth_filter(MPA_INT *synth_buf_ptr, int *synth_buf_offset,
802
                         MPA_INT *window, int *dither_state,
803
                         OUT_INT *samples, int incr,
804
                         int32_t sb_samples[SBLIMIT])
805
{
806
    register MPA_INT *synth_buf;
Alex Beregszaszi's avatar
Alex Beregszaszi committed
807
    register const MPA_INT *w, *w2, *p;
808
    int j, offset;
809
    OUT_INT *samples2;
810
#if FRAC_BITS <= 15
811
    int32_t tmp[32];
812
    int sum, sum2;
813
#else
814
    int64_t sum, sum2;
815
#endif
816 817 818

    offset = *synth_buf_offset;
    synth_buf = synth_buf_ptr + offset;
819 820

#if FRAC_BITS <= 15
821 822
    dct32(tmp, sb_samples);
    for(j=0;j<32;j++) {
823 824
        /* NOTE: can cause a loss in precision if very high amplitude
           sound */
825
        synth_buf[j] = av_clip_int16(tmp[j]);
826
    }
827 828 829 830
#else
    dct32(synth_buf, sb_samples);
#endif

831 832 833
    /* copy to avoid wrap */
    memcpy(synth_buf + 512, synth_buf, 32 * sizeof(MPA_INT));

834
    samples2 = samples + 31 * incr;
835
    w = window;
836 837
    w2 = window + 31;

838
    sum = *dither_state;
839
    p = synth_buf + 16;
840
    SUM8(MACS, sum, w, p);
841
    p = synth_buf + 48;
842
    SUM8(MLSS, sum, w + 32, p);
843
    *samples = round_sample(&sum);
844
    samples += incr;
845 846
    w++;

847 848 849 850 851
    /* we calculate two samples at the same time to avoid one memory
       access per two sample */
    for(j=1;j<16;j++) {
        sum2 = 0;
        p = synth_buf + 16 + j;
852
        SUM8P2(sum, MACS, sum2, MLSS, w, w2, p);
853
        p = synth_buf + 48 - j;
854
        SUM8P2(sum, MLSS, sum2, MLSS, w + 32, w2 + 32, p);
855

856
        *samples = round_sample(&sum);
857
        samples += incr;
858 859
        sum += sum2;
        *samples2 = round_sample(&sum);
860
        samples2 -= incr;
861
        w++;
862
        w2--;
863
    }
864

865
    p = synth_buf + 32;
866
    SUM8(MLSS, sum, w + 32, p);
867
    *samples = round_sample(&sum);
868
    *dither_state= sum;
869

870
    offset = (offset - 32) & 511;
871
    *synth_buf_offset = offset;
872 873
}

Michael Niedermayer's avatar
Michael Niedermayer committed
874 875 876 877 878 879 880 881 882 883 884 885 886 887
#define C3 FIXHR(0.86602540378443864676/2)

/* 0.5 / cos(pi*(2*i+1)/36) */
static const int icos36[9] = {
    FIXR(0.50190991877167369479),
    FIXR(0.51763809020504152469), //0
    FIXR(0.55168895948124587824),
    FIXR(0.61038729438072803416),
    FIXR(0.70710678118654752439), //1
    FIXR(0.87172339781054900991),
    FIXR(1.18310079157624925896),
    FIXR(1.93185165257813657349), //2
    FIXR(5.73685662283492756461),
};
888

889 890 891 892 893 894 895 896 897 898 899 900 901
/* 0.5 / cos(pi*(2*i+1)/36) */
static const int icos36h[9] = {
    FIXHR(0.50190991877167369479/2),
    FIXHR(0.51763809020504152469/2), //0
    FIXHR(0.55168895948124587824/2),
    FIXHR(0.61038729438072803416/2),
    FIXHR(0.70710678118654752439/2), //1
    FIXHR(0.87172339781054900991/2),
    FIXHR(1.18310079157624925896/4),
    FIXHR(1.93185165257813657349/4), //2
//    FIXHR(5.73685662283492756461),
};

902 903 904 905
/* 12 points IMDCT. We compute it "by hand" by factorizing obvious
   cases. */
static void imdct12(int *out, int *in)
{
Michael Niedermayer's avatar
Michael Niedermayer committed
906
    int in0, in1, in2, in3, in4, in5, t1, t2;
907 908 909 910 911 912 913

    in0= in[0*3];
    in1= in[1*3] + in[0*3];
    in2= in[2*3] + in[1*3];
    in3= in[3*3] + in[2*3];
    in4= in[4*3] + in[3*3];
    in5= in[5*3] + in[4*3];
Michael Niedermayer's avatar
Michael Niedermayer committed
914 915 916 917
    in5 += in3;
    in3 += in1;

    in2= MULH(2*in2, C3);
918
    in3= MULH(4*in3, C3);
919

Michael Niedermayer's avatar
Michael Niedermayer committed
920
    t1 = in0 - in4;
921
    t2 = MULH(2*(in1 - in5), icos36h[4]);
Michael Niedermayer's avatar
Michael Niedermayer committed
922

923
    out[ 7]=
Michael Niedermayer's avatar
Michael Niedermayer committed
924 925 926 927 928 929
    out[10]= t1 + t2;
    out[ 1]=
    out[ 4]= t1 - t2;

    in0 += in4>>1;
    in4 = in0 + in2;
930 931
    in5 += 2*in1;
    in1 = MULH(in5 + in3, icos36h[1]);
932
    out[ 8]=
933
    out[ 9]= in4 + in1;
Michael Niedermayer's avatar
Michael Niedermayer committed
934
    out[ 2]=
935
    out[ 3]= in4 - in1;
936

Michael Niedermayer's avatar
Michael Niedermayer committed
937
    in0 -= in2;
938
    in5 = MULH(2*(in5 - in3), icos36h[7]);
Michael Niedermayer's avatar
Michael Niedermayer committed
939
    out[ 0]=
940
    out[ 5]= in0 - in5;
Michael Niedermayer's avatar
Michael Niedermayer committed
941
    out[ 6]=
942
    out[11]= in0 + in5;
943 944 945
}

/* cos(pi*i/18) */
946 947 948 949 950 951 952 953 954
#define C1 FIXHR(0.98480775301220805936/2)
#define C2 FIXHR(0.93969262078590838405/2)
#define C3 FIXHR(0.86602540378443864676/2)
#define C4 FIXHR(0.76604444311897803520/2)
#define C5 FIXHR(0.64278760968653932632/2)
#define C6 FIXHR(0.5/2)
#define C7 FIXHR(0.34202014332566873304/2)
#define C8 FIXHR(0.17364817766693034885/2)

955 956

/* using Lee like decomposition followed by hand coded 9 points DCT */
957
static void imdct36(int *out, int *buf, int *in, int *win)
958 959 960 961 962 963 964 965 966 967 968 969
{
    int i, j, t0, t1, t2, t3, s0, s1, s2, s3;
    int tmp[18], *tmp1, *in1;

    for(i=17;i>=1;i--)
        in[i] += in[i-1];
    for(i=17;i>=3;i-=2)
        in[i] += in[i-2];

    for(j=0;j<2;j++) {
        tmp1 = tmp + j;
        in1 = in + j;
970 971 972 973
#if 0
//more accurate but slower
        int64_t t0, t1, t2, t3;
        t2 = in1[2*4] + in1[2*8] - in1[2*2];
974

975 976 977 978 979 980 981 982
        t3 = (in1[2*0] + (int64_t)(in1[2*6]>>1))<<32;
        t1 = in1[2*0] - in1[2*6];
        tmp1[ 6] = t1 - (t2>>1);
        tmp1[16] = t1 + t2;

        t0 = MUL64(2*(in1[2*2] + in1[2*4]),    C2);
        t1 = MUL64(   in1[2*4] - in1[2*8] , -2*C8);
        t2 = MUL64(2*(in1[2*2] + in1[2*8]),   -C4);
983

984 985 986
        tmp1[10] = (t3 - t0 - t2) >> 32;
        tmp1[ 2] = (t3 + t0 + t1) >> 32;
        tmp1[14] = (t3 + t2 - t1) >> 32;
987

988 989 990 991 992 993 994 995 996 997 998 999
        tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7] - in1[2*1]), -C3);
        t2 = MUL64(2*(in1[2*1] + in1[2*5]),    C1);
        t3 = MUL64(   in1[2*5] - in1[2*7] , -2*C7);
        t0 = MUL64(2*in1[2*3], C3);

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

        tmp1[ 0] = (t2 + t3 + t0) >> 32;
        tmp1[12] = (t2 + t1 - t0) >> 32;
        tmp1[ 8] = (t3 - t1 - t0) >> 32;
#else
        t2 = in1[2*4] + in1[2*8] - in1[2*2];
1000

1001 1002 1003 1004 1005 1006 1007 1008
        t3 = in1[2*0] + (in1[2*6]>>1);
        t1 = in1[2*0] - in1[2*6];
        tmp1[ 6] = t1 - (t2>>1);
        tmp1[16] = t1 + t2;

        t0 = MULH(2*(in1[2*2] + in1[2*4]),    C2);
        t1 = MULH(   in1[2*4] - in1[2*8] , -2*C8);
        t2 = MULH(2*(in1[2*2] + in1[2*8]),   -C4);
1009

1010 1011 1012
        tmp1[10] = t3 - t0 - t2;
        tmp1[ 2] = t3 + t0 + t1;
        tmp1[14] = t3 + t2 - t1;
1013

1014 1015 1016 1017
        tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7] - in1[2*1]), -C3);
        t2 = MULH(2*(in1[2*1] + in1[2*5]),    C1);
        t3 = MULH(   in1[2*5] - in1[2*7] , -2*C7);
        t0 = MULH(2*in1[2*3], C3);
1018

1019 1020 1021 1022 1023 1024
        t1 = MULH(2*(in1[2*1] + in1[2*7]),   -C5);

        tmp1[ 0] = t2 + t3 + t0;
        tmp1[12] = t2 + t1 - t0;
        tmp1[ 8] = t3 - t1 - t0;
#endif
1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035
    }

    i = 0;
    for(j=0;j<4;j++) {
        t0 = tmp[i];
        t1 = tmp[i + 2];
        s0 = t1 + t0;
        s2 = t1 - t0;

        t2 = tmp[i + 1];
        t3 = tmp[i + 3];
1036
        s1 = MULH(2*(t3 + t2), icos36h[j]);
1037
        s3 = MULL(t3 - t2, icos36[8 - j], FRAC_BITS);
1038

1039 1040
        t0 = s0 + s1;
        t1 = s0 - s1;
Michael Niedermayer's avatar
Michael Niedermayer committed
1041
        out[(9 + j)*SBLIMIT] =  MULH(t1, win[9 + j]) + buf[9 + j];
1042 1043 1044
        out[(8 - j)*SBLIMIT] =  MULH(t1, win[8 - j]) + buf[8 - j];
        buf[9 + j] = MULH(t0, win[18 + 9 + j]);
        buf[8 - j] = MULH(t0, win[18 + 8 - j]);
1045

1046 1047
        t0 = s2 + s3;
        t1 = s2 - s3;
Michael Niedermayer's avatar
Michael Niedermayer committed
1048
        out[(9 + 8 - j)*SBLIMIT] =  MULH(t1, win[9 + 8 - j]) + buf[9 + 8 - j];
1049 1050 1051
        out[(        j)*SBLIMIT] =  MULH(t1, win[        j]) + buf[        j];
        buf[9 + 8 - j] = MULH(t0, win[18 + 9 + 8 - j]);
        buf[      + j] = MULH(t0, win[18         + j]);
1052 1053 1054 1055
        i += 4;
    }

    s0 = tmp[16];
1056
    s1 = MULH(2*tmp[17], icos36h[4]);
1057 1058
    t0 = s0 + s1;
    t1 = s0 - s1;
Michael Niedermayer's avatar
Michael Niedermayer committed
1059
    out[(9 + 4)*SBLIMIT] =  MULH(t1, win[9 + 4]) + buf[9 + 4];
1060 1061 1062
    out[(8 - 4)*SBLIMIT] =  MULH(t1, win[8 - 4]) + buf[8 - 4];
    buf[9 + 4] = MULH(t0, win[18 + 9 + 4]);
    buf[8 - 4] = MULH(t0, win[18 + 8 - 4]);
1063 1064 1065 1066
}

/* return the number of decoded frames */
static int mp_decode_layer1(MPADecodeContext *s)
Fabrice Bellard's avatar
Fabrice Bellard committed
1067
{
1068
    int bound, i, v, n, ch, j, mant;
1069 1070
    uint8_t allocation[MPA_MAX_CHANNELS][SBLIMIT];
    uint8_t scale_factors[MPA_MAX_CHANNELS][SBLIMIT];
1071

1072
    if (s->mode == MPA_JSTEREO)
1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099
        bound = (s->mode_ext + 1) * 4;
    else
        bound = SBLIMIT;

    /* allocation bits */
    for(i=0;i<bound;i++) {
        for(ch=0;ch<s->nb_channels;ch++) {
            allocation[ch][i] = get_bits(&s->gb, 4);
        }
    }
    for(i=bound;i<SBLIMIT;i++) {
        allocation[0][i] = get_bits(&s->gb, 4);
    }

    /* scale factors */
    for(i=0;i<bound;i++) {
        for(ch=0;ch<s->nb_channels;ch++) {
            if (allocation[ch][i])
                scale_factors[ch][i] = get_bits(&s->gb, 6);
        }
    }
    for(i=bound;i<SBLIMIT;i++) {
        if (allocation[0][i]) {
            scale_factors[0][i] = get_bits(&s->gb, 6);
            scale_factors[1][i] = get_bits(&s->gb, 6);
        }
    }
1100

1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140
    /* compute samples */
    for(j=0;j<12;j++) {
        for(i=0;i<bound;i++) {
            for(ch=0;ch<s->nb_channels;ch++) {
                n = allocation[ch][i];
                if (n) {
                    mant = get_bits(&s->gb, n + 1);
                    v = l1_unscale(n, mant, scale_factors[ch][i]);
                } else {
                    v = 0;
                }
                s->sb_samples[ch][j][i] = v;
            }
        }
        for(i=bound;i<SBLIMIT;i++) {
            n = allocation[0][i];
            if (n) {
                mant = get_bits(&s->gb, n + 1);
                v = l1_unscale(n, mant, scale_factors[0][i]);
                s->sb_samples[0][j][i] = v;
                v = l1_unscale(n, mant, scale_factors[1][i]);
                s->sb_samples[1][j][i] = v;
            } else {
                s->sb_samples[0][j][i] = 0;
                s->sb_samples[1][j][i] = 0;
            }
        }
    }
    return 12;
}

static int mp_decode_layer2(MPADecodeContext *s)
{
    int sblimit; /* number of used subbands */
    const unsigned char *alloc_table;
    int table, bit_alloc_bits, i, j, ch, bound, v;
    unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT];
    unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT];
    unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3], *sf;
    int scale, qindex, bits, steps, k, l, m, b;
Fabrice Bellard's avatar
Fabrice Bellard committed
1141

1142
    /* select decoding table */
1143
    table = ff_mpa_l2_select_table(s->bit_rate / 1000, s->nb_channels,
1144
                            s->sample_rate, s->lsf);
1145 1146
    sblimit = ff_mpa_sblimit_table[table];
    alloc_table = ff_mpa_alloc_tables[table];
1147

1148
    if (s->mode == MPA_JSTEREO)
1149 1150 1151 1152
        bound = (s->mode_ext + 1) * 4;
    else
        bound = sblimit;

1153
    dprintf(s->avctx, "bound=%d sblimit=%d\n", bound, sblimit);
1154 1155 1156 1157

    /* sanity check */
    if( bound > sblimit ) bound = sblimit;

1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172
    /* parse bit allocation */
    j = 0;
    for(i=0;i<bound;i++) {
        bit_alloc_bits = alloc_table[j];
        for(ch=0;ch<s->nb_channels;ch++) {
            bit_alloc[ch][i] = get_bits(&s->gb, bit_alloc_bits);
        }
        j += 1 << bit_alloc_bits;
    }
    for(i=bound;i<sblimit;i++) {
        bit_alloc_bits = alloc_table[j];
        v = get_bits(&s->gb, bit_alloc_bits);
        bit_alloc[0][i] = v;
        bit_alloc[1][i] = v;
        j += 1 << bit_alloc_bits;
Fabrice Bellard's avatar
Fabrice Bellard committed
1173
    }
1174 1175 1176 1177

    /* scale codes */
    for(i=0;i<sblimit;i++) {
        for(ch=0;ch<s->nb_channels;ch++) {
1178
            if (bit_alloc[ch][i])
1179 1180 1181
                scale_code[ch][i] = get_bits(&s->gb, 2);
        }
    }
1182

1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225
    /* scale factors */
    for(i=0;i<sblimit;i++) {
        for(ch=0;ch<s->nb_channels;ch++) {
            if (bit_alloc[ch][i]) {
                sf = scale_factors[ch][i];
                switch(scale_code[ch][i]) {
                default:
                case 0:
                    sf[0] = get_bits(&s->gb, 6);
                    sf[1] = get_bits(&s->gb, 6);
                    sf[2] = get_bits(&s->gb, 6);
                    break;
                case 2:
                    sf[0] = get_bits(&s->gb, 6);
                    sf[1] = sf[0];
                    sf[2] = sf[0];
                    break;
                case 1:
                    sf[0] = get_bits(&s->gb, 6);
                    sf[2] = get_bits(&s->gb, 6);
                    sf[1] = sf[0];
                    break;
                case 3:
                    sf[0] = get_bits(&s->gb, 6);
                    sf[2] = get_bits(&s->gb, 6);
                    sf[1] = sf[2];
                    break;
                }
            }
        }
    }

    /* samples */
    for(k=0;k<3;k++) {
        for(l=0;l<12;l+=3) {
            j = 0;
            for(i=0;i<bound;i++) {
                bit_alloc_bits = alloc_table[j];
                for(ch=0;ch<s->nb_channels;ch++) {
                    b = bit_alloc[ch][i];
                    if (b) {
                        scale = scale_factors[ch][i][k];
                        qindex = alloc_table[j+b];
1226
                        bits = ff_mpa_quant_bits[qindex];
1227 1228 1229
                        if (bits < 0) {
                            /* 3 values at the same time */
                            v = get_bits(&s->gb, -bits);
1230
                            steps = ff_mpa_quant_steps[qindex];
1231
                            s->sb_samples[ch][k * 12 + l + 0][i] =
1232 1233
                                l2_unscale_group(steps, v % steps, scale);
                            v = v / steps;
1234
                            s->sb_samples[ch][k * 12 + l + 1][i] =
1235 1236
                                l2_unscale_group(steps, v % steps, scale);
                            v = v / steps;
1237
                            s->sb_samples[ch][k * 12 + l + 2][i] =
1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252
                                l2_unscale_group(steps, v, scale);
                        } else {
                            for(m=0;m<3;m++) {
                                v = get_bits(&s->gb, bits);
                                v = l1_unscale(bits - 1, v, scale);
                                s->sb_samples[ch][k * 12 + l + m][i] = v;
                            }
                        }
                    } else {
                        s->sb_samples[ch][k * 12 + l + 0][i] = 0;
                        s->sb_samples[ch][k * 12 + l + 1][i] = 0;
                        s->sb_samples[ch][k * 12 + l + 2][i] = 0;
                    }
                }
                /* next subband in alloc table */
1253
                j += 1 << bit_alloc_bits;
1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
            }
            /* XXX: find a way to avoid this duplication of code */
            for(i=bound;i<sblimit;i++) {
                bit_alloc_bits = alloc_table[j];
                b = bit_alloc[0][i];
                if (b) {
                    int mant, scale0, scale1;
                    scale0 = scale_factors[0][i][k];
                    scale1 = scale_factors[1][i][k];
                    qindex = alloc_table[j+b];
1264
                    bits = ff_mpa_quant_bits[qindex];
1265 1266 1267
                    if (bits < 0) {
                        /* 3 values at the same time */
                        v = get_bits(&s->gb, -bits);
1268
                        steps = ff_mpa_quant_steps[qindex];
1269 1270
                        mant = v % steps;
                        v = v / steps;
1271
                        s->sb_samples[0][k * 12 + l + 0][i] =
1272
                            l2_unscale_group(steps, mant, scale0);
1273
                        s->sb_samples[1][k * 12 + l + 0][i] =
1274 1275 1276
                            l2_unscale_group(steps, mant, scale1);
                        mant = v % steps;
                        v = v / steps;
1277
                        s->sb_samples[0][k * 12 + l + 1][i] =
1278
                            l2_unscale_group(steps, mant, scale0);
1279
                        s->sb_samples[1][k * 12 + l + 1][i] =
1280
                            l2_unscale_group(steps, mant, scale1);
1281
                        s->sb_samples[0][k * 12 + l + 2][i] =
1282
                            l2_unscale_group(steps, v, scale0);
1283
                        s->sb_samples[1][k * 12 + l + 2][i] =
1284 1285 1286 1287
                            l2_unscale_group(steps, v, scale1);
                    } else {
                        for(m=0;m<3;m++) {
                            mant = get_bits(&s->gb, bits);
1288
                            s->sb_samples[0][k * 12 + l + m][i] =
1289
                                l1_unscale(bits - 1, mant, scale0);
1290
                            s->sb_samples[1][k * 12 + l + m][i] =
1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302
                                l1_unscale(bits - 1, mant, scale1);
                        }
                    }
                } else {
                    s->sb_samples[0][k * 12 + l + 0][i] = 0;
                    s->sb_samples[0][k * 12 + l + 1][i] = 0;
                    s->sb_samples[0][k * 12 + l + 2][i] = 0;
                    s->sb_samples[1][k * 12 + l + 0][i] = 0;
                    s->sb_samples[1][k * 12 + l + 1][i] = 0;
                    s->sb_samples[1][k * 12 + l + 2][i] = 0;
                }
                /* next subband in alloc table */
1303
                j += 1 << bit_alloc_bits;
1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315
            }
            /* fill remaining samples to zero */
            for(i=sblimit;i<SBLIMIT;i++) {
                for(ch=0;ch<s->nb_channels;ch++) {
                    s->sb_samples[ch][k * 12 + l + 0][i] = 0;
                    s->sb_samples[ch][k * 12 + l + 1][i] = 0;
                    s->sb_samples[ch][k * 12 + l + 2][i] = 0;
                }
            }
        }
    }
    return 3 * 12;
Fabrice Bellard's avatar
Fabrice Bellard committed
1316 1317
}

1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337
static inline void lsf_sf_expand(int *slen,
                                 int sf, int n1, int n2, int n3)
{
    if (n3) {
        slen[3] = sf % n3;
        sf /= n3;
    } else {
        slen[3] = 0;
    }
    if (n2) {
        slen[2] = sf % n2;
        sf /= n2;
    } else {
        slen[2] = 0;
    }
    slen[1] = sf % n1;
    sf /= n1;
    slen[0] = sf;
}

1338
static void exponents_from_scale_factors(MPADecodeContext *s,
1339
                                         GranuleDef *g,
1340
                                         int16_t *exponents)
1341
{
1342
    const uint8_t *bstab, *pretab;
1343
    int len, i, j, k, l, v0, shift, gain, gains[3];
1344
    int16_t *exp_ptr;
1345 1346 1347 1348 1349 1350 1351 1352

    exp_ptr = exponents;
    gain = g->global_gain - 210;
    shift = g->scalefac_scale + 1;

    bstab = band_size_long[s->sample_rate_index];
    pretab = mpa_pretab[g->preflag];
    for(i=0;i<g->long_end;i++) {
1353
        v0 = gain - ((g->scale_factors[i] + pretab[i]) << shift) + 400;
1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367
        len = bstab[i];
        for(j=len;j>0;j--)
            *exp_ptr++ = v0;
    }

    if (g->short_start < 13) {
        bstab = band_size_short[s->sample_rate_index];
        gains[0] = gain - (g->subblock_gain[0] << 3);
        gains[1] = gain - (g->subblock_gain[1] << 3);
        gains[2] = gain - (g->subblock_gain[2] << 3);
        k = g->long_end;
        for(i=g->short_start;i<13;i++) {
            len = bstab[i];
            for(l=0;l<3;l++) {
1368
                v0 = gains[l] - (g->scale_factors[k++] << shift) + 400;
1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384
                for(j=len;j>0;j--)
                *exp_ptr++ = v0;
            }
        }
    }
}

/* handle n = 0 too */
static inline int get_bitsz(GetBitContext *s, int n)
{
    if (n == 0)
        return 0;
    else
        return get_bits(s, n);
}

1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397

static void switch_buffer(MPADecodeContext *s, int *pos, int *end_pos, int *end_pos2){
    if(s->in_gb.buffer && *pos >= s->gb.size_in_bits){
        s->gb= s->in_gb;
        s->in_gb.buffer=NULL;
        assert((get_bits_count(&s->gb) & 7) == 0);
        skip_bits_long(&s->gb, *pos - *end_pos);
        *end_pos2=
        *end_pos= *end_pos2 + get_bits_count(&s->gb) - *pos;
        *pos= get_bits_count(&s->gb);
    }
}

1398
static int huffman_decode(MPADecodeContext *s, GranuleDef *g,
1399
                          int16_t *exponents, int end_pos2)
1400 1401
{
    int s_index;
1402
    int i;
1403
    int last_pos, bits_left;
1404
    VLC *vlc;
1405
    int end_pos= FFMIN(end_pos2, s->gb.size_in_bits);
1406 1407 1408 1409

    /* low frequencies (called big values) */
    s_index = 0;
    for(i=0;i<3;i++) {
1410
        int j, k, l, linbits;
1411 1412 1413 1414 1415 1416 1417 1418 1419
        j = g->region_size[i];
        if (j == 0)
            continue;
        /* select vlc table */
        k = g->table_select[i];
        l = mpa_huff_data[k][0];
        linbits = mpa_huff_data[k][1];
        vlc = &huff_vlc[l];

1420
        if(!l){
1421
            memset(&g->sb_hybrid[s_index], 0, sizeof(*g->sb_hybrid)*2*j);
1422 1423 1424 1425
            s_index += 2*j;
            continue;
        }

1426 1427
        /* read huffcode and compute each couple */
        for(;j>0;j--) {
1428
            int exponent, x, y, v;
1429 1430 1431 1432
            int pos= get_bits_count(&s->gb);

            if (pos >= end_pos){
//                av_log(NULL, AV_LOG_ERROR, "pos: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);
1433
                switch_buffer(s, &pos, &end_pos, &end_pos2);
1434 1435 1436 1437
//                av_log(NULL, AV_LOG_ERROR, "new pos: %d %d\n", pos, end_pos);
                if(pos >= end_pos)
                    break;
            }
1438
            y = get_vlc2(&s->gb, vlc->table, 7, 3);
1439 1440 1441 1442 1443 1444 1445 1446

            if(!y){
                g->sb_hybrid[s_index  ] =
                g->sb_hybrid[s_index+1] = 0;
                s_index += 2;
                continue;
            }

1447
            exponent= exponents[s_index];
1448

1449
            dprintf(s->avctx, "region=%d n=%d x=%d y=%d exp=%d\n",
1450
                    i, g->region_size[i] - j, x, y, exponent);
Michael Niedermayer's avatar
Michael Niedermayer committed
1451 1452 1453
            if(y&16){
                x = y >> 5;
                y = y & 0x0f;
1454
                if (x < 15){
1455 1456
                    v = expval_table[ exponent ][ x ];
//                      v = expval_table[ (exponent&3) ][ x ] >> FFMIN(0 - (exponent>>2), 31);
1457 1458
                }else{
                    x += get_bitsz(&s->gb, linbits);
1459
                    v = l3_unscale(x, exponent);
1460
                }
1461 1462
                if (get_bits1(&s->gb))
                    v = -v;
Michael Niedermayer's avatar
Michael Niedermayer committed
1463
                g->sb_hybrid[s_index] = v;
1464
                if (y < 15){
1465
                    v = expval_table[ exponent ][ y ];
1466 1467
                }else{
                    y += get_bitsz(&s->gb, linbits);
1468
                    v = l3_unscale(y, exponent);
1469
                }
1470 1471
                if (get_bits1(&s->gb))
                    v = -v;
Michael Niedermayer's avatar
Michael Niedermayer committed
1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485
                g->sb_hybrid[s_index+1] = v;
            }else{
                x = y >> 5;
                y = y & 0x0f;
                x += y;
                if (x < 15){
                    v = expval_table[ exponent ][ x ];
                }else{
                    x += get_bitsz(&s->gb, linbits);
                    v = l3_unscale(x, exponent);
                }
                if (get_bits1(&s->gb))
                    v = -v;
                g->sb_hybrid[s_index+!!y] = v;
1486
                g->sb_hybrid[s_index+ !y] = 0;
1487
            }
Michael Niedermayer's avatar
Michael Niedermayer committed
1488
            s_index+=2;
1489 1490
        }
    }
1491

1492 1493
    /* high frequencies */
    vlc = &huff_quad_vlc[g->count1table_select];
1494
    last_pos=0;
1495
    while (s_index <= 572) {
1496
        int pos, code;
1497 1498
        pos = get_bits_count(&s->gb);
        if (pos >= end_pos) {
1499 1500 1501 1502 1503
            if (pos > end_pos2 && last_pos){
                /* some encoders generate an incorrect size for this
                   part. We must go back into the data */
                s_index -= 4;
                skip_bits_long(&s->gb, last_pos - pos);
1504
                av_log(s->avctx, AV_LOG_INFO, "overread, skip %d enddists: %d %d\n", last_pos - pos, end_pos-pos, end_pos2-pos);
1505
                if(s->error_recognition >= FF_ER_COMPLIANT)
1506
                    s_index=0;
1507 1508
                break;
            }
1509
//                av_log(NULL, AV_LOG_ERROR, "pos2: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);
1510
            switch_buffer(s, &pos, &end_pos, &end_pos2);
1511 1512 1513
//                av_log(NULL, AV_LOG_ERROR, "new pos2: %d %d %d\n", pos, end_pos, s_index);
            if(pos >= end_pos)
                break;
1514
        }
1515
        last_pos= pos;
1516

1517
        code = get_vlc2(&s->gb, vlc->table, vlc->bits, 1);
1518
        dprintf(s->avctx, "t=%d code=%d\n", g->count1table_select, code);
1519 1520 1521 1522 1523
        g->sb_hybrid[s_index+0]=
        g->sb_hybrid[s_index+1]=
        g->sb_hybrid[s_index+2]=
        g->sb_hybrid[s_index+3]= 0;
        while(code){
1524
            static const int idxtab[16]={3,3,2,2,1,1,1,1,0,0,0,0,0,0,0,0};
1525
            int v;
1526 1527
            int pos= s_index+idxtab[code];
            code ^= 8>>idxtab[code];
1528 1529
            v = exp_table[ exponents[pos] ];
//            v = exp_table[ (exponents[pos]&3) ] >> FFMIN(0 - (exponents[pos]>>2), 31);
1530 1531 1532
            if(get_bits1(&s->gb))
                v = -v;
            g->sb_hybrid[pos] = v;
1533
        }
1534
        s_index+=4;
1535
    }
1536
    /* skip extension bits */
1537
    bits_left = end_pos2 - get_bits_count(&s->gb);
1538
//av_log(NULL, AV_LOG_ERROR, "left:%d buf:%p\n", bits_left, s->in_gb.buffer);
1539
    if (bits_left < 0 && s->error_recognition >= FF_ER_COMPLIANT) {
1540
        av_log(s->avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);
1541
        s_index=0;
1542
    }else if(bits_left > 0 && s->error_recognition >= FF_ER_AGGRESSIVE){
1543
        av_log(s->avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);
1544
        s_index=0;
1545
    }
1546
    memset(&g->sb_hybrid[s_index], 0, sizeof(*g->sb_hybrid)*(576 - s_index));
1547 1548
    skip_bits_long(&s->gb, bits_left);

1549
    i= get_bits_count(&s->gb);
1550
    switch_buffer(s, &i, &end_pos, &end_pos2);
1551

Fabrice Bellard's avatar
Fabrice Bellard committed
1552 1553 1554
    return 0;
}

1555 1556 1557 1558 1559
/* Reorder short blocks from bitstream order to interleaved order. It
   would be faster to do it in parsing, but the code would be far more
   complicated */
static void reorder_block(MPADecodeContext *s, GranuleDef *g)
{
1560
    int i, j, len;
1561 1562
    int32_t *ptr, *dst, *ptr1;
    int32_t tmp[576];
1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575

    if (g->block_type != 2)
        return;

    if (g->switch_point) {
        if (s->sample_rate_index != 8) {
            ptr = g->sb_hybrid + 36;
        } else {
            ptr = g->sb_hybrid + 48;
        }
    } else {
        ptr = g->sb_hybrid;
    }
1576

1577 1578 1579
    for(i=g->short_start;i<13;i++) {
        len = band_size_short[s->sample_rate_index][i];
        ptr1 = ptr;
1580 1581 1582 1583 1584 1585
        dst = tmp;
        for(j=len;j>0;j--) {
            *dst++ = ptr[0*len];
            *dst++ = ptr[1*len];
            *dst++ = ptr[2*len];
            ptr++;
1586
        }
1587 1588
        ptr+=2*len;
        memcpy(ptr1, tmp, len * 3 * sizeof(*ptr1));
1589 1590 1591 1592 1593 1594 1595 1596 1597
    }
}

#define ISQRT2 FIXR(0.70710678118654752440)

static void compute_stereo(MPADecodeContext *s,
                           GranuleDef *g0, GranuleDef *g1)
{
    int i, j, k, l;
1598
    int32_t v1, v2;
1599
    int sf_max, tmp0, tmp1, sf, len, non_zero_found;
1600 1601
    int32_t (*is_tab)[16];
    int32_t *tab0, *tab1;
1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612
    int non_zero_found_short[3];

    /* intensity stereo */
    if (s->mode_ext & MODE_EXT_I_STEREO) {
        if (!s->lsf) {
            is_tab = is_table;
            sf_max = 7;
        } else {
            is_tab = is_table_lsf[g1->scalefac_compress & 1];
            sf_max = 16;
        }
1613

1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644
        tab0 = g0->sb_hybrid + 576;
        tab1 = g1->sb_hybrid + 576;

        non_zero_found_short[0] = 0;
        non_zero_found_short[1] = 0;
        non_zero_found_short[2] = 0;
        k = (13 - g1->short_start) * 3 + g1->long_end - 3;
        for(i = 12;i >= g1->short_start;i--) {
            /* for last band, use previous scale factor */
            if (i != 11)
                k -= 3;
            len = band_size_short[s->sample_rate_index][i];
            for(l=2;l>=0;l--) {
                tab0 -= len;
                tab1 -= len;
                if (!non_zero_found_short[l]) {
                    /* test if non zero band. if so, stop doing i-stereo */
                    for(j=0;j<len;j++) {
                        if (tab1[j] != 0) {
                            non_zero_found_short[l] = 1;
                            goto found1;
                        }
                    }
                    sf = g1->scale_factors[k + l];
                    if (sf >= sf_max)
                        goto found1;

                    v1 = is_tab[0][sf];
                    v2 = is_tab[1][sf];
                    for(j=0;j<len;j++) {
                        tmp0 = tab0[j];
1645 1646
                        tab0[j] = MULL(tmp0, v1, FRAC_BITS);
                        tab1[j] = MULL(tmp0, v2, FRAC_BITS);
1647 1648 1649 1650 1651 1652 1653 1654 1655
                    }
                } else {
                found1:
                    if (s->mode_ext & MODE_EXT_MS_STEREO) {
                        /* lower part of the spectrum : do ms stereo
                           if enabled */
                        for(j=0;j<len;j++) {
                            tmp0 = tab0[j];
                            tmp1 = tab1[j];
1656 1657
                            tab0[j] = MULL(tmp0 + tmp1, ISQRT2, FRAC_BITS);
                            tab1[j] = MULL(tmp0 - tmp1, ISQRT2, FRAC_BITS);
1658 1659 1660 1661 1662 1663
                        }
                    }
                }
            }
        }

1664 1665
        non_zero_found = non_zero_found_short[0] |
            non_zero_found_short[1] |
1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688
            non_zero_found_short[2];

        for(i = g1->long_end - 1;i >= 0;i--) {
            len = band_size_long[s->sample_rate_index][i];
            tab0 -= len;
            tab1 -= len;
            /* test if non zero band. if so, stop doing i-stereo */
            if (!non_zero_found) {
                for(j=0;j<len;j++) {
                    if (tab1[j] != 0) {
                        non_zero_found = 1;
                        goto found2;
                    }
                }
                /* for last band, use previous scale factor */
                k = (i == 21) ? 20 : i;
                sf = g1->scale_factors[k];
                if (sf >= sf_max)
                    goto found2;
                v1 = is_tab[0][sf];
                v2 = is_tab[1][sf];
                for(j=0;j<len;j++) {
                    tmp0 = tab0[j];
1689 1690
                    tab0[j] = MULL(tmp0, v1, FRAC_BITS);
                    tab1[j] = MULL(tmp0, v2, FRAC_BITS);
1691 1692 1693 1694 1695 1696 1697 1698 1699
                }
            } else {
            found2:
                if (s->mode_ext & MODE_EXT_MS_STEREO) {
                    /* lower part of the spectrum : do ms stereo
                       if enabled */
                    for(j=0;j<len;j++) {
                        tmp0 = tab0[j];
                        tmp1 = tab1[j];
1700 1701
                        tab0[j] = MULL(tmp0 + tmp1, ISQRT2, FRAC_BITS);
                        tab1[j] = MULL(tmp0 - tmp1, ISQRT2, FRAC_BITS);
1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720
                    }
                }
            }
        }
    } else if (s->mode_ext & MODE_EXT_MS_STEREO) {
        /* ms stereo ONLY */
        /* NOTE: the 1/sqrt(2) normalization factor is included in the
           global gain */
        tab0 = g0->sb_hybrid;
        tab1 = g1->sb_hybrid;
        for(i=0;i<576;i++) {
            tmp0 = tab0[i];
            tmp1 = tab1[i];
            tab0[i] = tmp0 + tmp1;
            tab1[i] = tmp0 - tmp1;
        }
    }
}

1721
static void compute_antialias_integer(MPADecodeContext *s,
1722 1723
                              GranuleDef *g)
{
Michael Niedermayer's avatar
Michael Niedermayer committed
1724 1725
    int32_t *ptr, *csa;
    int n, i;
1726 1727 1728 1729 1730 1731 1732 1733 1734 1735

    /* we antialias only "long" bands */
    if (g->block_type == 2) {
        if (!g->switch_point)
            return;
        /* XXX: check this for 8000Hz case */
        n = 1;
    } else {
        n = SBLIMIT - 1;
    }
1736

1737 1738
    ptr = g->sb_hybrid + 18;
    for(i = n;i > 0;i--) {
Michael Niedermayer's avatar
Michael Niedermayer committed
1739 1740 1741
        int tmp0, tmp1, tmp2;
        csa = &csa_table[0][0];
#define INT_AA(j) \
1742 1743
            tmp0 = ptr[-1-j];\
            tmp1 = ptr[   j];\
Michael Niedermayer's avatar
Michael Niedermayer committed
1744
            tmp2= MULH(tmp0 + tmp1, csa[0+4*j]);\
1745 1746
            ptr[-1-j] = 4*(tmp2 - MULH(tmp1, csa[2+4*j]));\
            ptr[   j] = 4*(tmp2 + MULH(tmp0, csa[3+4*j]));
Michael Niedermayer's avatar
Michael Niedermayer committed
1747 1748 1749 1750 1751 1752 1753 1754 1755

        INT_AA(0)
        INT_AA(1)
        INT_AA(2)
        INT_AA(3)
        INT_AA(4)
        INT_AA(5)
        INT_AA(6)
        INT_AA(7)
1756 1757

        ptr += 18;
1758 1759 1760 1761 1762 1763
    }
}

static void compute_antialias_float(MPADecodeContext *s,
                              GranuleDef *g)
{
Michael Niedermayer's avatar
Michael Niedermayer committed
1764 1765
    int32_t *ptr;
    int n, i;
1766 1767 1768 1769 1770 1771 1772 1773 1774 1775

    /* we antialias only "long" bands */
    if (g->block_type == 2) {
        if (!g->switch_point)
            return;
        /* XXX: check this for 8000Hz case */
        n = 1;
    } else {
        n = SBLIMIT - 1;
    }
1776

1777 1778
    ptr = g->sb_hybrid + 18;
    for(i = n;i > 0;i--) {
Michael Niedermayer's avatar
Michael Niedermayer committed
1779
        float tmp0, tmp1;
1780
        float *csa = &csa_table_float[0][0];
Michael Niedermayer's avatar
Michael Niedermayer committed
1781 1782 1783 1784 1785
#define FLOAT_AA(j)\
        tmp0= ptr[-1-j];\
        tmp1= ptr[   j];\
        ptr[-1-j] = lrintf(tmp0 * csa[0+4*j] - tmp1 * csa[1+4*j]);\
        ptr[   j] = lrintf(tmp0 * csa[1+4*j] + tmp1 * csa[0+4*j]);
1786

Michael Niedermayer's avatar
Michael Niedermayer committed
1787 1788 1789 1790 1791 1792 1793 1794 1795
        FLOAT_AA(0)
        FLOAT_AA(1)
        FLOAT_AA(2)
        FLOAT_AA(3)
        FLOAT_AA(4)
        FLOAT_AA(5)
        FLOAT_AA(6)
        FLOAT_AA(7)

1796
        ptr += 18;
1797 1798 1799 1800
    }
}

static void compute_imdct(MPADecodeContext *s,
1801
                          GranuleDef *g,
1802 1803
                          int32_t *sb_samples,
                          int32_t *mdct_buf)
1804
{
Michael Niedermayer's avatar
Michael Niedermayer committed
1805
    int32_t *ptr, *win, *win1, *buf, *out_ptr, *ptr1;
1806
    int32_t out2[12];
Michael Niedermayer's avatar
Michael Niedermayer committed
1807
    int i, j, mdct_long_end, v, sblimit;
1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841

    /* find last non zero block */
    ptr = g->sb_hybrid + 576;
    ptr1 = g->sb_hybrid + 2 * 18;
    while (ptr >= ptr1) {
        ptr -= 6;
        v = ptr[0] | ptr[1] | ptr[2] | ptr[3] | ptr[4] | ptr[5];
        if (v != 0)
            break;
    }
    sblimit = ((ptr - g->sb_hybrid) / 18) + 1;

    if (g->block_type == 2) {
        /* XXX: check for 8000 Hz */
        if (g->switch_point)
            mdct_long_end = 2;
        else
            mdct_long_end = 0;
    } else {
        mdct_long_end = sblimit;
    }

    buf = mdct_buf;
    ptr = g->sb_hybrid;
    for(j=0;j<mdct_long_end;j++) {
        /* apply window & overlap with previous buffer */
        out_ptr = sb_samples + j;
        /* select window */
        if (g->switch_point && j < 2)
            win1 = mdct_win[0];
        else
            win1 = mdct_win[g->block_type];
        /* select frequency inversion */
        win = win1 + ((4 * 36) & -(j & 1));
1842 1843
        imdct36(out_ptr, buf, ptr, win);
        out_ptr += 18*SBLIMIT;
1844 1845 1846 1847 1848 1849 1850
        ptr += 18;
        buf += 18;
    }
    for(j=mdct_long_end;j<sblimit;j++) {
        /* select frequency inversion */
        win = mdct_win[2] + ((4 * 36) & -(j & 1));
        out_ptr = sb_samples + j;
1851

Michael Niedermayer's avatar
Michael Niedermayer committed
1852 1853 1854 1855 1856 1857 1858 1859
        for(i=0; i<6; i++){
            *out_ptr = buf[i];
            out_ptr += SBLIMIT;
        }
        imdct12(out2, ptr + 0);
        for(i=0;i<6;i++) {
            *out_ptr = MULH(out2[i], win[i]) + buf[i + 6*1];
            buf[i + 6*2] = MULH(out2[i + 6], win[i + 6]);
1860 1861
            out_ptr += SBLIMIT;
        }
Michael Niedermayer's avatar
Michael Niedermayer committed
1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873
        imdct12(out2, ptr + 1);
        for(i=0;i<6;i++) {
            *out_ptr = MULH(out2[i], win[i]) + buf[i + 6*2];
            buf[i + 6*0] = MULH(out2[i + 6], win[i + 6]);
            out_ptr += SBLIMIT;
        }
        imdct12(out2, ptr + 2);
        for(i=0;i<6;i++) {
            buf[i + 6*0] = MULH(out2[i], win[i]) + buf[i + 6*0];
            buf[i + 6*1] = MULH(out2[i + 6], win[i + 6]);
            buf[i + 6*2] = 0;
        }
1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893
        ptr += 18;
        buf += 18;
    }
    /* zero bands */
    for(j=sblimit;j<SBLIMIT;j++) {
        /* overlap */
        out_ptr = sb_samples + j;
        for(i=0;i<18;i++) {
            *out_ptr = buf[i];
            buf[i] = 0;
            out_ptr += SBLIMIT;
        }
        buf += 18;
    }
}

/* main layer3 decoding function */
static int mp_decode_layer3(MPADecodeContext *s)
{
    int nb_granules, main_data_begin, private_bits;
1894
    int gr, ch, blocksplit_flag, i, j, k, n, bits_pos;
1895
    GranuleDef *g;
1896
    int16_t exponents[576];
1897 1898 1899 1900

    /* read side info */
    if (s->lsf) {
        main_data_begin = get_bits(&s->gb, 8);
Michael Niedermayer's avatar
Michael Niedermayer committed
1901
        private_bits = get_bits(&s->gb, s->nb_channels);
1902 1903 1904 1905 1906 1907 1908 1909 1910
        nb_granules = 1;
    } else {
        main_data_begin = get_bits(&s->gb, 9);
        if (s->nb_channels == 2)
            private_bits = get_bits(&s->gb, 3);
        else
            private_bits = get_bits(&s->gb, 5);
        nb_granules = 2;
        for(ch=0;ch<s->nb_channels;ch++) {
1911 1912
            s->granules[ch][0].scfsi = 0;/* all scale factors are transmitted */
            s->granules[ch][1].scfsi = get_bits(&s->gb, 4);
1913 1914
        }
    }
1915

1916 1917
    for(gr=0;gr<nb_granules;gr++) {
        for(ch=0;ch<s->nb_channels;ch++) {
1918
            dprintf(s->avctx, "gr=%d ch=%d: side_info\n", gr, ch);
1919
            g = &s->granules[ch][gr];
1920 1921
            g->part2_3_length = get_bits(&s->gb, 12);
            g->big_values = get_bits(&s->gb, 9);
1922
            if(g->big_values > 288){
1923
                av_log(s->avctx, AV_LOG_ERROR, "big_values too big\n");
1924 1925 1926
                return -1;
            }

1927 1928 1929
            g->global_gain = get_bits(&s->gb, 8);
            /* if MS stereo only is selected, we precompute the
               1/sqrt(2) renormalization factor */
1930
            if ((s->mode_ext & (MODE_EXT_MS_STEREO | MODE_EXT_I_STEREO)) ==
1931 1932 1933 1934 1935 1936
                MODE_EXT_MS_STEREO)
                g->global_gain -= 2;
            if (s->lsf)
                g->scalefac_compress = get_bits(&s->gb, 9);
            else
                g->scalefac_compress = get_bits(&s->gb, 4);
1937
            blocksplit_flag = get_bits1(&s->gb);
1938 1939
            if (blocksplit_flag) {
                g->block_type = get_bits(&s->gb, 2);
1940
                if (g->block_type == 0){
1941
                    av_log(s->avctx, AV_LOG_ERROR, "invalid block type\n");
1942
                    return -1;
1943
                }
1944
                g->switch_point = get_bits1(&s->gb);
1945 1946
                for(i=0;i<2;i++)
                    g->table_select[i] = get_bits(&s->gb, 5);
1947
                for(i=0;i<3;i++)
1948
                    g->subblock_gain[i] = get_bits(&s->gb, 3);
1949
                ff_init_short_region(s, g);
1950
            } else {
1951
                int region_address1, region_address2;
1952 1953 1954 1955 1956 1957 1958
                g->block_type = 0;
                g->switch_point = 0;
                for(i=0;i<3;i++)
                    g->table_select[i] = get_bits(&s->gb, 5);
                /* compute huffman coded region sizes */
                region_address1 = get_bits(&s->gb, 4);
                region_address2 = get_bits(&s->gb, 3);
1959
                dprintf(s->avctx, "region1=%d region2=%d\n",
1960
                        region_address1, region_address2);
1961
                ff_init_long_region(s, g, region_address1, region_address2);
1962
            }
1963 1964
            ff_region_offset2size(g);
            ff_compute_band_indexes(s, g);
1965

1966 1967
            g->preflag = 0;
            if (!s->lsf)
1968 1969 1970
                g->preflag = get_bits1(&s->gb);
            g->scalefac_scale = get_bits1(&s->gb);
            g->count1table_select = get_bits1(&s->gb);
1971
            dprintf(s->avctx, "block_type=%d switch_point=%d\n",
1972 1973 1974 1975
                    g->block_type, g->switch_point);
        }
    }

Roberto Togni's avatar
Roberto Togni committed
1976
  if (!s->adu_mode) {
1977
    const uint8_t *ptr = s->gb.buffer + (get_bits_count(&s->gb)>>3);
1978
    assert((get_bits_count(&s->gb) & 7) == 0);
1979
    /* now we get bits from the main_data_begin offset */
1980
    dprintf(s->avctx, "seekback: %d\n", main_data_begin);
1981 1982 1983 1984
//av_log(NULL, AV_LOG_ERROR, "backstep:%d, lastbuf:%d\n", main_data_begin, s->last_buf_size);

    memcpy(s->last_buf + s->last_buf_size, ptr, EXTRABYTES);
    s->in_gb= s->gb;
1985 1986
        init_get_bits(&s->gb, s->last_buf, s->last_buf_size*8);
        skip_bits_long(&s->gb, 8*(s->last_buf_size - main_data_begin));
Roberto Togni's avatar
Roberto Togni committed
1987
  }
1988 1989 1990

    for(gr=0;gr<nb_granules;gr++) {
        for(ch=0;ch<s->nb_channels;ch++) {
1991
            g = &s->granules[ch][gr];
1992
            if(get_bits_count(&s->gb)<0){
1993
                av_log(s->avctx, AV_LOG_DEBUG, "mdb:%d, lastbuf:%d skipping granule %d\n",
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
                                            main_data_begin, s->last_buf_size, gr);
                skip_bits_long(&s->gb, g->part2_3_length);
                memset(g->sb_hybrid, 0, sizeof(g->sb_hybrid));
                if(get_bits_count(&s->gb) >= s->gb.size_in_bits && s->in_gb.buffer){
                    skip_bits_long(&s->in_gb, get_bits_count(&s->gb) - s->gb.size_in_bits);
                    s->gb= s->in_gb;
                    s->in_gb.buffer=NULL;
                }
                continue;
            }
2004

2005
            bits_pos = get_bits_count(&s->gb);
2006

2007
            if (!s->lsf) {
2008
                uint8_t *sc;
2009 2010 2011 2012 2013
                int slen, slen1, slen2;

                /* MPEG1 scale factors */
                slen1 = slen_table[0][g->scalefac_compress];
                slen2 = slen_table[1][g->scalefac_compress];
2014
                dprintf(s->avctx, "slen1=%d slen2=%d\n", slen1, slen2);
2015 2016 2017
                if (g->block_type == 2) {
                    n = g->switch_point ? 17 : 18;
                    j = 0;
2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033
                    if(slen1){
                        for(i=0;i<n;i++)
                            g->scale_factors[j++] = get_bits(&s->gb, slen1);
                    }else{
                        for(i=0;i<n;i++)
                            g->scale_factors[j++] = 0;
                    }
                    if(slen2){
                        for(i=0;i<18;i++)
                            g->scale_factors[j++] = get_bits(&s->gb, slen2);
                        for(i=0;i<3;i++)
                            g->scale_factors[j++] = 0;
                    }else{
                        for(i=0;i<21;i++)
                            g->scale_factors[j++] = 0;
                    }
2034
                } else {
2035
                    sc = s->granules[ch][0].scale_factors;
2036 2037 2038 2039 2040
                    j = 0;
                    for(k=0;k<4;k++) {
                        n = (k == 0 ? 6 : 5);
                        if ((g->scfsi & (0x8 >> k)) == 0) {
                            slen = (k < 2) ? slen1 : slen2;
2041 2042 2043 2044 2045 2046 2047
                            if(slen){
                                for(i=0;i<n;i++)
                                    g->scale_factors[j++] = get_bits(&s->gb, slen);
                            }else{
                                for(i=0;i<n;i++)
                                    g->scale_factors[j++] = 0;
                            }
2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099
                        } else {
                            /* simply copy from last granule */
                            for(i=0;i<n;i++) {
                                g->scale_factors[j] = sc[j];
                                j++;
                            }
                        }
                    }
                    g->scale_factors[j++] = 0;
                }
            } else {
                int tindex, tindex2, slen[4], sl, sf;

                /* LSF scale factors */
                if (g->block_type == 2) {
                    tindex = g->switch_point ? 2 : 1;
                } else {
                    tindex = 0;
                }
                sf = g->scalefac_compress;
                if ((s->mode_ext & MODE_EXT_I_STEREO) && ch == 1) {
                    /* intensity stereo case */
                    sf >>= 1;
                    if (sf < 180) {
                        lsf_sf_expand(slen, sf, 6, 6, 0);
                        tindex2 = 3;
                    } else if (sf < 244) {
                        lsf_sf_expand(slen, sf - 180, 4, 4, 0);
                        tindex2 = 4;
                    } else {
                        lsf_sf_expand(slen, sf - 244, 3, 0, 0);
                        tindex2 = 5;
                    }
                } else {
                    /* normal case */
                    if (sf < 400) {
                        lsf_sf_expand(slen, sf, 5, 4, 4);
                        tindex2 = 0;
                    } else if (sf < 500) {
                        lsf_sf_expand(slen, sf - 400, 5, 4, 0);
                        tindex2 = 1;
                    } else {
                        lsf_sf_expand(slen, sf - 500, 3, 0, 0);
                        tindex2 = 2;
                        g->preflag = 1;
                    }
                }

                j = 0;
                for(k=0;k<4;k++) {
                    n = lsf_nsf_table[tindex2][tindex][k];
                    sl = slen[k];
Michael Niedermayer's avatar
Michael Niedermayer committed
2100
                    if(sl){
2101 2102 2103 2104 2105 2106
                        for(i=0;i<n;i++)
                            g->scale_factors[j++] = get_bits(&s->gb, sl);
                    }else{
                        for(i=0;i<n;i++)
                            g->scale_factors[j++] = 0;
                    }
2107 2108 2109 2110 2111 2112 2113 2114 2115
                }
                /* XXX: should compute exact size */
                for(;j<40;j++)
                    g->scale_factors[j] = 0;
            }

            exponents_from_scale_factors(s, g, exponents);

            /* read Huffman coded residue */
2116
            huffman_decode(s, g, exponents, bits_pos + g->part2_3_length);
2117 2118 2119
        } /* ch */

        if (s->nb_channels == 2)
2120
            compute_stereo(s, &s->granules[0][gr], &s->granules[1][gr]);
2121 2122

        for(ch=0;ch<s->nb_channels;ch++) {
2123
            g = &s->granules[ch][gr];
2124 2125

            reorder_block(s, g);
2126
            s->compute_antialias(s, g);
2127
            compute_imdct(s, g, &s->sb_samples[ch][18 * gr][0], s->mdct_buf[ch]);
2128 2129
        }
    } /* gr */
2130 2131
    if(get_bits_count(&s->gb)<0)
        skip_bits_long(&s->gb, -get_bits_count(&s->gb));
2132 2133 2134
    return nb_granules * 18;
}

2135
static int mp_decode_frame(MPADecodeContext *s,
2136
                           OUT_INT *samples, const uint8_t *buf, int buf_size)
2137 2138
{
    int i, nb_frames, ch;
2139
    OUT_INT *samples_ptr;
2140

2141
    init_get_bits(&s->gb, buf + HEADER_SIZE, (buf_size - HEADER_SIZE)*8);
2142

2143 2144
    /* skip error protection field */
    if (s->error_protection)
2145
        skip_bits(&s->gb, 16);
2146

2147
    dprintf(s->avctx, "frame %d:\n", s->frame_count);
2148 2149
    switch(s->layer) {
    case 1:
2150
        s->avctx->frame_size = 384;
2151 2152 2153
        nb_frames = mp_decode_layer1(s);
        break;
    case 2:
2154
        s->avctx->frame_size = 1152;
2155 2156 2157
        nb_frames = mp_decode_layer2(s);
        break;
    case 3:
2158
        s->avctx->frame_size = s->lsf ? 576 : 1152;
2159 2160
    default:
        nb_frames = mp_decode_layer3(s);
2161

2162 2163 2164
        s->last_buf_size=0;
        if(s->in_gb.buffer){
            align_get_bits(&s->gb);
2165
            i= get_bits_left(&s->gb)>>3;
2166
            if(i >= 0 && i <= BACKSTEP_SIZE){
2167 2168
                memmove(s->last_buf, s->gb.buffer + (get_bits_count(&s->gb)>>3), i);
                s->last_buf_size=i;
2169
            }else
2170
                av_log(s->avctx, AV_LOG_ERROR, "invalid old backstep %d\n", i);
2171
            s->gb= s->in_gb;
2172
            s->in_gb.buffer= NULL;
2173 2174
        }

2175 2176
        align_get_bits(&s->gb);
        assert((get_bits_count(&s->gb) & 7) == 0);
2177
        i= get_bits_left(&s->gb)>>3;
2178

2179
        if(i<0 || i > BACKSTEP_SIZE || nb_frames<0){
2180 2181
            if(i<0)
                av_log(s->avctx, AV_LOG_ERROR, "invalid new backstep %d\n", i);
2182 2183
            i= FFMIN(BACKSTEP_SIZE, buf_size - HEADER_SIZE);
        }
2184
        assert(i <= buf_size - HEADER_SIZE && i>= 0);
2185
        memcpy(s->last_buf + s->last_buf_size, s->gb.buffer + buf_size - HEADER_SIZE - i, i);
2186
        s->last_buf_size += i;
2187

2188 2189
        break;
    }
2190

2191 2192 2193 2194
    /* apply the synthesis filter */
    for(ch=0;ch<s->nb_channels;ch++) {
        samples_ptr = samples + ch;
        for(i=0;i<nb_frames;i++) {
2195
            ff_mpa_synth_filter(s->synth_buf[ch], &(s->synth_buf_offset[ch]),
2196
                         ff_mpa_synth_window, &s->dither_state,
2197
                         samples_ptr, s->nb_channels,
2198 2199 2200 2201
                         s->sb_samples[ch][i]);
            samples_ptr += 32 * s->nb_channels;
        }
    }
2202

2203
    return nb_frames * 32 * sizeof(OUT_INT) * s->nb_channels;
2204 2205
}

Fabrice Bellard's avatar
Fabrice Bellard committed
2206
static int decode_frame(AVCodecContext * avctx,
2207
                        void *data, int *data_size,
2208
                        AVPacket *avpkt)
Fabrice Bellard's avatar
Fabrice Bellard committed
2209
{
2210 2211
    const uint8_t *buf = avpkt->data;
    int buf_size = avpkt->size;
Fabrice Bellard's avatar
Fabrice Bellard committed
2212
    MPADecodeContext *s = avctx->priv_data;
2213
    uint32_t header;
2214
    int out_size;
2215
    OUT_INT *out_samples = data;
Fabrice Bellard's avatar
Fabrice Bellard committed
2216

2217 2218 2219
    if(buf_size < HEADER_SIZE)
        return -1;

2220
    header = AV_RB32(buf);
2221
    if(ff_mpa_check_header(header) < 0){
2222 2223
        av_log(avctx, AV_LOG_ERROR, "Header missing\n");
        return -1;
2224 2225
    }

2226
    if (ff_mpegaudio_decode_header((MPADecodeHeader *)s, header) == 1) {
2227 2228 2229 2230 2231 2232 2233 2234 2235
        /* free format: prepare to compute frame size */
        s->frame_size = -1;
        return -1;
    }
    /* update codec info */
    avctx->channels = s->nb_channels;
    avctx->bit_rate = s->bit_rate;
    avctx->sub_id = s->layer;

2236 2237
    if(*data_size < 1152*avctx->channels*sizeof(OUT_INT))
        return -1;
2238
    *data_size = 0;
2239

2240
    if(s->frame_size<=0 || s->frame_size > buf_size){
2241 2242
        av_log(avctx, AV_LOG_ERROR, "incomplete frame\n");
        return -1;
2243 2244
    }else if(s->frame_size < buf_size){
        av_log(avctx, AV_LOG_ERROR, "incorrect frame size\n");
2245
        buf_size= s->frame_size;
Fabrice Bellard's avatar
Fabrice Bellard committed
2246
    }
2247 2248

    out_size = mp_decode_frame(s, out_samples, buf, buf_size);
2249
    if(out_size>=0){
2250
        *data_size = out_size;
2251 2252 2253
        avctx->sample_rate = s->sample_rate;
        //FIXME maybe move the other codec info stuff from above here too
    }else
Diego Biurrun's avatar
Diego Biurrun committed
2254
        av_log(avctx, AV_LOG_DEBUG, "Error while decoding MPEG audio frame.\n"); //FIXME return -1 / but also return the number of bytes consumed
2255
    s->frame_size = 0;
2256
    return buf_size;
Fabrice Bellard's avatar
Fabrice Bellard committed
2257 2258
}

2259 2260
static void flush(AVCodecContext *avctx){
    MPADecodeContext *s = avctx->priv_data;
2261
    memset(s->synth_buf, 0, sizeof(s->synth_buf));
2262 2263 2264
    s->last_buf_size= 0;
}

2265
#if CONFIG_MP3ADU_DECODER
Roberto Togni's avatar
Roberto Togni committed
2266
static int decode_frame_adu(AVCodecContext * avctx,
2267
                        void *data, int *data_size,
2268
                        AVPacket *avpkt)
Roberto Togni's avatar
Roberto Togni committed
2269
{
2270 2271
    const uint8_t *buf = avpkt->data;
    int buf_size = avpkt->size;
Roberto Togni's avatar
Roberto Togni committed
2272 2273 2274
    MPADecodeContext *s = avctx->priv_data;
    uint32_t header;
    int len, out_size;
2275
    OUT_INT *out_samples = data;
Roberto Togni's avatar
Roberto Togni committed
2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289

    len = buf_size;

    // Discard too short frames
    if (buf_size < HEADER_SIZE) {
        *data_size = 0;
        return buf_size;
    }


    if (len > MPA_MAX_CODED_FRAME_SIZE)
        len = MPA_MAX_CODED_FRAME_SIZE;

    // Get header and restore sync word
2290
    header = AV_RB32(buf) | 0xffe00000;
Roberto Togni's avatar
Roberto Togni committed
2291

2292
    if (ff_mpa_check_header(header) < 0) { // Bad header, discard frame
Roberto Togni's avatar
Roberto Togni committed
2293 2294 2295 2296
        *data_size = 0;
        return buf_size;
    }

2297
    ff_mpegaudio_decode_header((MPADecodeHeader *)s, header);
Roberto Togni's avatar
Roberto Togni committed
2298 2299 2300 2301 2302 2303
    /* update codec info */
    avctx->sample_rate = s->sample_rate;
    avctx->channels = s->nb_channels;
    avctx->bit_rate = s->bit_rate;
    avctx->sub_id = s->layer;

2304
    s->frame_size = len;
Roberto Togni's avatar
Roberto Togni committed
2305 2306

    if (avctx->parse_only) {
2307
        out_size = buf_size;
Roberto Togni's avatar
Roberto Togni committed
2308
    } else {
2309
        out_size = mp_decode_frame(s, out_samples, buf, buf_size);
Roberto Togni's avatar
Roberto Togni committed
2310 2311 2312 2313 2314
    }

    *data_size = out_size;
    return buf_size;
}
2315
#endif /* CONFIG_MP3ADU_DECODER */
Roberto Togni's avatar
Roberto Togni committed
2316

2317
#if CONFIG_MP3ON4_DECODER
2318

2319 2320 2321 2322 2323 2324
/**
 * Context for MP3On4 decoder
 */
typedef struct MP3On4DecodeContext {
    int frames;   ///< number of mp3 frames per block (number of mp3 decoder instances)
    int syncword; ///< syncword patch
2325
    const uint8_t *coff; ///< channels offsets in output buffer
2326 2327 2328
    MPADecodeContext *mp3decctx[5]; ///< MPADecodeContext for every decoder instance
} MP3On4DecodeContext;

2329 2330
#include "mpeg4audio.h"

2331
/* Next 3 arrays are indexed by channel config number (passed via codecdata) */
2332
static const uint8_t mp3Frames[8] = {0,1,1,2,3,3,4,5};   /* number of mp3 decoder instances */
2333
/* offsets into output buffer, assume output order is FL FR BL BR C LFE */
2334
static const uint8_t chan_offset[8][5] = {
2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348
    {0},
    {0},            // C
    {0},            // FLR
    {2,0},          // C FLR
    {2,0,3},        // C FLR BS
    {4,0,2},        // C FLR BLRS
    {4,0,2,5},      // C FLR BLRS LFE
    {4,0,2,6,5},    // C FLR BLRS BLR LFE
};


static int decode_init_mp3on4(AVCodecContext * avctx)
{
    MP3On4DecodeContext *s = avctx->priv_data;
2349
    MPEG4AudioConfig cfg;
2350 2351 2352 2353 2354 2355 2356
    int i;

    if ((avctx->extradata_size < 2) || (avctx->extradata == NULL)) {
        av_log(avctx, AV_LOG_ERROR, "Codec extradata missing or too short.\n");
        return -1;
    }

2357 2358
    ff_mpeg4audio_get_config(&cfg, avctx->extradata, avctx->extradata_size);
    if (!cfg.chan_config || cfg.chan_config > 7) {
2359 2360 2361
        av_log(avctx, AV_LOG_ERROR, "Invalid channel config number.\n");
        return -1;
    }
2362 2363 2364
    s->frames = mp3Frames[cfg.chan_config];
    s->coff = chan_offset[cfg.chan_config];
    avctx->channels = ff_mpeg4audio_channels[cfg.chan_config];
2365

2366 2367 2368 2369 2370
    if (cfg.sample_rate < 16000)
        s->syncword = 0xffe00000;
    else
        s->syncword = 0xfff00000;

2371 2372 2373
    /* Init the first mp3 decoder in standard way, so that all tables get builded
     * We replace avctx->priv_data with the context of the first decoder so that
     * decode_init() does not have to be changed.
2374
     * Other decoders will be initialized here copying data from the first context
2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391
     */
    // Allocate zeroed memory for the first decoder context
    s->mp3decctx[0] = av_mallocz(sizeof(MPADecodeContext));
    // Put decoder context in place to make init_decode() happy
    avctx->priv_data = s->mp3decctx[0];
    decode_init(avctx);
    // Restore mp3on4 context pointer
    avctx->priv_data = s;
    s->mp3decctx[0]->adu_mode = 1; // Set adu mode

    /* Create a separate codec/context for each frame (first is already ok).
     * Each frame is 1 or 2 channels - up to 5 frames allowed
     */
    for (i = 1; i < s->frames; i++) {
        s->mp3decctx[i] = av_mallocz(sizeof(MPADecodeContext));
        s->mp3decctx[i]->compute_antialias = s->mp3decctx[0]->compute_antialias;
        s->mp3decctx[i]->adu_mode = 1;
2392
        s->mp3decctx[i]->avctx = avctx;
2393 2394 2395 2396 2397 2398
    }

    return 0;
}


2399
static av_cold int decode_close_mp3on4(AVCodecContext * avctx)
2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412
{
    MP3On4DecodeContext *s = avctx->priv_data;
    int i;

    for (i = 0; i < s->frames; i++)
        if (s->mp3decctx[i])
            av_free(s->mp3decctx[i]);

    return 0;
}


static int decode_frame_mp3on4(AVCodecContext * avctx,
2413
                        void *data, int *data_size,
2414
                        AVPacket *avpkt)
2415
{
2416 2417
    const uint8_t *buf = avpkt->data;
    int buf_size = avpkt->size;
2418 2419
    MP3On4DecodeContext *s = avctx->priv_data;
    MPADecodeContext *m;
2420
    int fsize, len = buf_size, out_size = 0;
2421 2422 2423 2424
    uint32_t header;
    OUT_INT *out_samples = data;
    OUT_INT decoded_buf[MPA_FRAME_SIZE * MPA_MAX_CHANNELS];
    OUT_INT *outptr, *bp;
2425
    int fr, j, n;
2426

2427 2428 2429
    if(*data_size < MPA_FRAME_SIZE * MPA_MAX_CHANNELS * s->frames * sizeof(OUT_INT))
        return -1;

2430
    *data_size = 0;
2431
    // Discard too short frames
2432 2433
    if (buf_size < HEADER_SIZE)
        return -1;
2434 2435 2436 2437

    // If only one decoder interleave is not needed
    outptr = s->frames == 1 ? out_samples : decoded_buf;

2438 2439
    avctx->bit_rate = 0;

2440
    for (fr = 0; fr < s->frames; fr++) {
Baptiste Coudurier's avatar
Baptiste Coudurier committed
2441
        fsize = AV_RB16(buf) >> 4;
2442
        fsize = FFMIN3(fsize, len, MPA_MAX_CODED_FRAME_SIZE);
2443 2444 2445
        m = s->mp3decctx[fr];
        assert (m != NULL);

2446
        header = (AV_RB32(buf) & 0x000fffff) | s->syncword; // patch header
2447

2448 2449
        if (ff_mpa_check_header(header) < 0) // Bad header, discard block
            break;
2450

2451
        ff_mpegaudio_decode_header((MPADecodeHeader *)m, header);
2452
        out_size += mp_decode_frame(m, outptr, buf, fsize);
Baptiste Coudurier's avatar
Baptiste Coudurier committed
2453 2454
        buf += fsize;
        len -= fsize;
2455 2456

        if(s->frames > 1) {
2457
            n = m->avctx->frame_size*m->nb_channels;
2458
            /* interleave output data */
2459
            bp = out_samples + s->coff[fr];
2460 2461 2462
            if(m->nb_channels == 1) {
                for(j = 0; j < n; j++) {
                    *bp = decoded_buf[j];
Baptiste Coudurier's avatar
Baptiste Coudurier committed
2463
                    bp += avctx->channels;
2464 2465 2466 2467 2468
                }
            } else {
                for(j = 0; j < n; j++) {
                    bp[0] = decoded_buf[j++];
                    bp[1] = decoded_buf[j];
Baptiste Coudurier's avatar
Baptiste Coudurier committed
2469
                    bp += avctx->channels;
2470 2471 2472
                }
            }
        }
2473
        avctx->bit_rate += m->bit_rate;
2474 2475 2476 2477 2478 2479 2480 2481
    }

    /* update codec info */
    avctx->sample_rate = s->mp3decctx[0]->sample_rate;

    *data_size = out_size;
    return buf_size;
}
2482
#endif /* CONFIG_MP3ON4_DECODER */
2483

2484
#if CONFIG_MP1_DECODER
2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499
AVCodec mp1_decoder =
{
    "mp1",
    CODEC_TYPE_AUDIO,
    CODEC_ID_MP1,
    sizeof(MPADecodeContext),
    decode_init,
    NULL,
    NULL,
    decode_frame,
    CODEC_CAP_PARSE_ONLY,
    .flush= flush,
    .long_name= NULL_IF_CONFIG_SMALL("MP1 (MPEG audio layer 1)"),
};
#endif
2500
#if CONFIG_MP2_DECODER
2501
AVCodec mp2_decoder =
Fabrice Bellard's avatar
Fabrice Bellard committed
2502
{
2503
    "mp2",
Fabrice Bellard's avatar
Fabrice Bellard committed
2504 2505 2506 2507 2508 2509 2510
    CODEC_TYPE_AUDIO,
    CODEC_ID_MP2,
    sizeof(MPADecodeContext),
    decode_init,
    NULL,
    NULL,
    decode_frame,
2511
    CODEC_CAP_PARSE_ONLY,
2512
    .flush= flush,
2513
    .long_name= NULL_IF_CONFIG_SMALL("MP2 (MPEG audio layer 2)"),
Fabrice Bellard's avatar
Fabrice Bellard committed
2514
};
2515
#endif
2516
#if CONFIG_MP3_DECODER
2517 2518 2519 2520
AVCodec mp3_decoder =
{
    "mp3",
    CODEC_TYPE_AUDIO,
2521
    CODEC_ID_MP3,
2522 2523 2524 2525 2526
    sizeof(MPADecodeContext),
    decode_init,
    NULL,
    NULL,
    decode_frame,
2527
    CODEC_CAP_PARSE_ONLY,
2528
    .flush= flush,
2529
    .long_name= NULL_IF_CONFIG_SMALL("MP3 (MPEG audio layer 3)"),
2530
};
2531
#endif
2532
#if CONFIG_MP3ADU_DECODER
Roberto Togni's avatar
Roberto Togni committed
2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543
AVCodec mp3adu_decoder =
{
    "mp3adu",
    CODEC_TYPE_AUDIO,
    CODEC_ID_MP3ADU,
    sizeof(MPADecodeContext),
    decode_init,
    NULL,
    NULL,
    decode_frame_adu,
    CODEC_CAP_PARSE_ONLY,
2544
    .flush= flush,
2545
    .long_name= NULL_IF_CONFIG_SMALL("ADU (Application Data Unit) MP3 (MPEG audio layer 3)"),
Roberto Togni's avatar
Roberto Togni committed
2546
};
2547
#endif
2548
#if CONFIG_MP3ON4_DECODER
2549 2550 2551 2552 2553 2554 2555 2556 2557 2558
AVCodec mp3on4_decoder =
{
    "mp3on4",
    CODEC_TYPE_AUDIO,
    CODEC_ID_MP3ON4,
    sizeof(MP3On4DecodeContext),
    decode_init_mp3on4,
    NULL,
    decode_close_mp3on4,
    decode_frame_mp3on4,
2559
    .flush= flush,
2560
    .long_name= NULL_IF_CONFIG_SMALL("MP3onMP4"),
2561
};
2562
#endif