wmadec.c 27.6 KB
Newer Older
Fabrice Bellard's avatar
Fabrice Bellard committed
1 2 3 4
/*
 * WMA compatible decoder
 * Copyright (c) 2002 The FFmpeg Project.
 *
5 6 7
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
Fabrice Bellard's avatar
Fabrice Bellard committed
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 14 15 16 17
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * 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 24

/**
 * @file wmadec.c
 * WMA compatible decoder.
25
 * This decoder handles Microsoft Windows Media Audio data, versions 1 & 2.
26
 * WMA v1 is identified by audio format 0x160 in Microsoft media files
27 28 29 30
 * (ASF/AVI/WAV). WMA v2 is identified by audio format 0x161.
 *
 * To use this decoder, a calling application must supply the extra data
 * bytes provided with the WMA data. These are the extra, codec-specific
31 32
 * bytes at the end of a WAVEFORMATEX data structure. Transmit these bytes
 * to the decoder using the extradata[_size] fields in AVCodecContext. There
33
 * should be 4 extra bytes for v1 data and 6 extra bytes for v2 data.
Michael Niedermayer's avatar
Michael Niedermayer committed
34 35
 */

Fabrice Bellard's avatar
Fabrice Bellard committed
36
#include "avcodec.h"
Michael Niedermayer's avatar
Michael Niedermayer committed
37
#include "wma.h"
Fabrice Bellard's avatar
Fabrice Bellard committed
38

Michael Niedermayer's avatar
Michael Niedermayer committed
39 40
#undef NDEBUG
#include <assert.h>
41 42 43 44 45 46

#define EXPVLCBITS 8
#define EXPMAX ((19+EXPVLCBITS-1)/EXPVLCBITS)

#define HGAINVLCBITS 9
#define HGAINMAX ((13+HGAINVLCBITS-1)/HGAINVLCBITS)
47

48
static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len);
Fabrice Bellard's avatar
Fabrice Bellard committed
49

50
#ifdef TRACE
51
static void dump_shorts(WMACodecContext *s, const char *name, const short *tab, int n)
Fabrice Bellard's avatar
Fabrice Bellard committed
52 53 54
{
    int i;

55
    tprintf(s->avctx, "%s[%d]:\n", name, n);
Fabrice Bellard's avatar
Fabrice Bellard committed
56 57
    for(i=0;i<n;i++) {
        if ((i & 7) == 0)
58 59
            tprintf(s->avctx, "%4d: ", i);
        tprintf(s->avctx, " %5d.0", tab[i]);
Fabrice Bellard's avatar
Fabrice Bellard committed
60
        if ((i & 7) == 7)
61
            tprintf(s->avctx, "\n");
Fabrice Bellard's avatar
Fabrice Bellard committed
62 63 64
    }
}

65
static void dump_floats(WMACodecContext *s, const char *name, int prec, const float *tab, int n)
Fabrice Bellard's avatar
Fabrice Bellard committed
66 67 68
{
    int i;

69
    tprintf(s->avctx, "%s[%d]:\n", name, n);
Fabrice Bellard's avatar
Fabrice Bellard committed
70 71
    for(i=0;i<n;i++) {
        if ((i & 7) == 0)
72 73
            tprintf(s->avctx, "%4d: ", i);
        tprintf(s->avctx, " %8.*f", prec, tab[i]);
Fabrice Bellard's avatar
Fabrice Bellard committed
74
        if ((i & 7) == 7)
75
            tprintf(s->avctx, "\n");
Fabrice Bellard's avatar
Fabrice Bellard committed
76 77
    }
    if ((i & 7) != 0)
78
        tprintf(s->avctx, "\n");
Fabrice Bellard's avatar
Fabrice Bellard committed
79 80 81 82 83
}
#endif

static int wma_decode_init(AVCodecContext * avctx)
{
84
    WMACodecContext *s = avctx->priv_data;
Fabrice Bellard's avatar
Fabrice Bellard committed
85 86
    int i, flags1, flags2;
    uint8_t *extradata;
87

88 89
    s->avctx = avctx;

Fabrice Bellard's avatar
Fabrice Bellard committed
90 91 92 93
    /* extract flag infos */
    flags1 = 0;
    flags2 = 0;
    extradata = avctx->extradata;
Michael Niedermayer's avatar
Michael Niedermayer committed
94
    if (avctx->codec->id == CODEC_ID_WMAV1 && avctx->extradata_size >= 4) {
95 96
        flags1 = AV_RL16(extradata);
        flags2 = AV_RL16(extradata+2);
Michael Niedermayer's avatar
Michael Niedermayer committed
97
    } else if (avctx->codec->id == CODEC_ID_WMAV2 && avctx->extradata_size >= 6) {
98 99
        flags1 = AV_RL32(extradata);
        flags2 = AV_RL16(extradata+4);
Fabrice Bellard's avatar
Fabrice Bellard committed
100
    }
Michael Niedermayer's avatar
Michael Niedermayer committed
101 102
// for(i=0; i<avctx->extradata_size; i++)
//     av_log(NULL, AV_LOG_ERROR, "%02X ", extradata[i]);
Michael Niedermayer's avatar
Michael Niedermayer committed
103

Fabrice Bellard's avatar
Fabrice Bellard committed
104 105 106 107
    s->use_exp_vlc = flags2 & 0x0001;
    s->use_bit_reservoir = flags2 & 0x0002;
    s->use_variable_block_len = flags2 & 0x0004;

108 109
    if(ff_wma_init(avctx, flags2)<0)
        return -1;
Fabrice Bellard's avatar
Fabrice Bellard committed
110 111 112

    /* init MDCT */
    for(i = 0; i < s->nb_block_sizes; i++)
113
        ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1);
114

Fabrice Bellard's avatar
Fabrice Bellard committed
115
    if (s->use_noise_coding) {
Michael Niedermayer's avatar
Michael Niedermayer committed
116 117 118
        init_vlc(&s->hgain_vlc, HGAINVLCBITS, sizeof(ff_wma_hgain_huffbits),
                 ff_wma_hgain_huffbits, 1, 1,
                 ff_wma_hgain_huffcodes, 2, 2, 0);
Fabrice Bellard's avatar
Fabrice Bellard committed
119 120 121
    }

    if (s->use_exp_vlc) {
Michael Niedermayer's avatar
Michael Niedermayer committed
122 123 124
        init_vlc(&s->exp_vlc, EXPVLCBITS, sizeof(ff_wma_scale_huffbits), //FIXME move out of context
                 ff_wma_scale_huffbits, 1, 1,
                 ff_wma_scale_huffcodes, 4, 4, 0);
Fabrice Bellard's avatar
Fabrice Bellard committed
125 126 127 128
    } else {
        wma_lsp_to_curve_init(s, s->frame_len);
    }

129
    avctx->sample_fmt = SAMPLE_FMT_S16;
Fabrice Bellard's avatar
Fabrice Bellard committed
130 131 132
    return 0;
}

Michael Niedermayer's avatar
Michael Niedermayer committed
133 134 135 136 137 138
/**
 * compute x^-0.25 with an exponent and mantissa table. We use linear
 * interpolation to reduce the mantissa table size at a small speed
 * expense (linear interpolation approximately doubles the number of
 * bits of precision).
 */
139
static inline float pow_m1_4(WMACodecContext *s, float x)
Fabrice Bellard's avatar
Fabrice Bellard committed
140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157
{
    union {
        float f;
        unsigned int v;
    } u, t;
    unsigned int e, m;
    float a, b;

    u.f = x;
    e = u.v >> 23;
    m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
    /* build interpolation scale: 1 <= t < 2. */
    t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
    a = s->lsp_pow_m_table1[m];
    b = s->lsp_pow_m_table2[m];
    return s->lsp_pow_e_table[e] * (a + b * t.f);
}

158
static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len)
159
{
Fabrice Bellard's avatar
Fabrice Bellard committed
160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194
    float wdel, a, b;
    int i, e, m;

    wdel = M_PI / frame_len;
    for(i=0;i<frame_len;i++)
        s->lsp_cos_table[i] = 2.0f * cos(wdel * i);

    /* tables for x^-0.25 computation */
    for(i=0;i<256;i++) {
        e = i - 126;
        s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
    }

    /* NOTE: these two tables are needed to avoid two operations in
       pow_m1_4 */
    b = 1.0;
    for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) {
        m = (1 << LSP_POW_BITS) + i;
        a = (float)m * (0.5 / (1 << LSP_POW_BITS));
        a = pow(a, -0.25);
        s->lsp_pow_m_table1[i] = 2 * a - b;
        s->lsp_pow_m_table2[i] = b - a;
        b = a;
    }
#if 0
    for(i=1;i<20;i++) {
        float v, r1, r2;
        v = 5.0 / i;
        r1 = pow_m1_4(s, v);
        r2 = pow(v,-0.25);
        printf("%f^-0.25=%f e=%f\n", v, r1, r2 - r1);
    }
#endif
}

Michael Niedermayer's avatar
Michael Niedermayer committed
195 196 197 198
/**
 * NOTE: We use the same code as Vorbis here
 * @todo optimize it further with SSE/3Dnow
 */
199
static void wma_lsp_to_curve(WMACodecContext *s,
200
                             float *out, float *val_max_ptr,
Fabrice Bellard's avatar
Fabrice Bellard committed
201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225
                             int n, float *lsp)
{
    int i, j;
    float p, q, w, v, val_max;

    val_max = 0;
    for(i=0;i<n;i++) {
        p = 0.5f;
        q = 0.5f;
        w = s->lsp_cos_table[i];
        for(j=1;j<NB_LSP_COEFS;j+=2){
            q *= w - lsp[j - 1];
            p *= w - lsp[j];
        }
        p *= p * (2.0f - w);
        q *= q * (2.0f + w);
        v = p + q;
        v = pow_m1_4(s, v);
        if (v > val_max)
            val_max = v;
        out[i] = v;
    }
    *val_max_ptr = val_max;
}

Michael Niedermayer's avatar
Michael Niedermayer committed
226 227 228
/**
 * decode exponents coded with LSP coefficients (same idea as Vorbis)
 */
229
static void decode_exp_lsp(WMACodecContext *s, int ch)
Fabrice Bellard's avatar
Fabrice Bellard committed
230 231 232 233 234 235 236 237 238
{
    float lsp_coefs[NB_LSP_COEFS];
    int val, i;

    for(i = 0; i < NB_LSP_COEFS; i++) {
        if (i == 0 || i >= 8)
            val = get_bits(&s->gb, 3);
        else
            val = get_bits(&s->gb, 4);
Michael Niedermayer's avatar
Michael Niedermayer committed
239
        lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
Fabrice Bellard's avatar
Fabrice Bellard committed
240 241 242 243 244 245
    }

    wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
                     s->block_len, lsp_coefs);
}

Michael Niedermayer's avatar
Michael Niedermayer committed
246 247 248
/**
 * decode exponents coded with VLC codes
 */
249
static int decode_exp_vlc(WMACodecContext *s, int ch)
Fabrice Bellard's avatar
Fabrice Bellard committed
250 251 252 253
{
    int last_exp, n, code;
    const uint16_t *ptr, *band_ptr;
    float v, *q, max_scale, *q_end;
254

Fabrice Bellard's avatar
Fabrice Bellard committed
255 256 257 258 259 260 261
    band_ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
    ptr = band_ptr;
    q = s->exponents[ch];
    q_end = q + s->block_len;
    max_scale = 0;
    if (s->version == 1) {
        last_exp = get_bits(&s->gb, 5) + 10;
262 263
        /* XXX: use a table */
        v = pow(10, last_exp * (1.0 / 16.0));
Fabrice Bellard's avatar
Fabrice Bellard committed
264 265 266 267 268
        max_scale = v;
        n = *ptr++;
        do {
            *q++ = v;
        } while (--n);
Michael Niedermayer's avatar
Michael Niedermayer committed
269 270 271
    }else
        last_exp = 36;

Fabrice Bellard's avatar
Fabrice Bellard committed
272
    while (q < q_end) {
273
        code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX);
Fabrice Bellard's avatar
Fabrice Bellard committed
274 275 276 277
        if (code < 0)
            return -1;
        /* NOTE: this offset is the same as MPEG4 AAC ! */
        last_exp += code - 60;
278 279
        /* XXX: use a table */
        v = pow(10, last_exp * (1.0 / 16.0));
Fabrice Bellard's avatar
Fabrice Bellard committed
280 281 282 283 284 285 286 287 288 289 290
        if (v > max_scale)
            max_scale = v;
        n = *ptr++;
        do {
            *q++ = v;
        } while (--n);
    }
    s->max_exponent[ch] = max_scale;
    return 0;
}

291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345

/**
 * Apply MDCT window and add into output.
 *
 * We ensure that when the windows overlap their squared sum
 * is always 1 (MDCT reconstruction rule).
 */
static void wma_window(WMACodecContext *s, float *out)
{
    float *in = s->output;
    int block_len, bsize, n;

    /* left part */
    if (s->block_len_bits <= s->prev_block_len_bits) {
        block_len = s->block_len;
        bsize = s->frame_len_bits - s->block_len_bits;

        s->dsp.vector_fmul_add_add(out, in, s->windows[bsize],
                                   out, 0, block_len, 1);

    } else {
        block_len = 1 << s->prev_block_len_bits;
        n = (s->block_len - block_len) / 2;
        bsize = s->frame_len_bits - s->prev_block_len_bits;

        s->dsp.vector_fmul_add_add(out+n, in+n, s->windows[bsize],
                                   out+n, 0, block_len, 1);

        memcpy(out+n+block_len, in+n+block_len, n*sizeof(float));
    }

    out += s->block_len;
    in += s->block_len;

    /* right part */
    if (s->block_len_bits <= s->next_block_len_bits) {
        block_len = s->block_len;
        bsize = s->frame_len_bits - s->block_len_bits;

        s->dsp.vector_fmul_reverse(out, in, s->windows[bsize], block_len);

    } else {
        block_len = 1 << s->next_block_len_bits;
        n = (s->block_len - block_len) / 2;
        bsize = s->frame_len_bits - s->next_block_len_bits;

        memcpy(out, in, n*sizeof(float));

        s->dsp.vector_fmul_reverse(out+n, in+n, s->windows[bsize], block_len);

        memset(out+n+block_len, 0, n*sizeof(float));
    }
}


Michael Niedermayer's avatar
Michael Niedermayer committed
346 347 348 349
/**
 * @return 0 if OK. 1 if last block of frame. return -1 if
 * unrecorrable error.
 */
350
static int wma_decode_block(WMACodecContext *s)
Fabrice Bellard's avatar
Fabrice Bellard committed
351 352
{
    int n, v, a, ch, code, bsize;
353
    int coef_nb_bits, total_gain;
Fabrice Bellard's avatar
Fabrice Bellard committed
354 355 356
    int nb_coefs[MAX_CHANNELS];
    float mdct_norm;

357
#ifdef TRACE
358
    tprintf(s->avctx, "***decode_block: %d:%d\n", s->frame_count - 1, s->block_num);
359
#endif
Fabrice Bellard's avatar
Fabrice Bellard committed
360 361 362 363

    /* compute current block length */
    if (s->use_variable_block_len) {
        n = av_log2(s->nb_block_sizes - 1) + 1;
364

Fabrice Bellard's avatar
Fabrice Bellard committed
365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396
        if (s->reset_block_lengths) {
            s->reset_block_lengths = 0;
            v = get_bits(&s->gb, n);
            if (v >= s->nb_block_sizes)
                return -1;
            s->prev_block_len_bits = s->frame_len_bits - v;
            v = get_bits(&s->gb, n);
            if (v >= s->nb_block_sizes)
                return -1;
            s->block_len_bits = s->frame_len_bits - v;
        } else {
            /* update block lengths */
            s->prev_block_len_bits = s->block_len_bits;
            s->block_len_bits = s->next_block_len_bits;
        }
        v = get_bits(&s->gb, n);
        if (v >= s->nb_block_sizes)
            return -1;
        s->next_block_len_bits = s->frame_len_bits - v;
    } else {
        /* fixed block len */
        s->next_block_len_bits = s->frame_len_bits;
        s->prev_block_len_bits = s->frame_len_bits;
        s->block_len_bits = s->frame_len_bits;
    }

    /* now check if the block length is coherent with the frame length */
    s->block_len = 1 << s->block_len_bits;
    if ((s->block_pos + s->block_len) > s->frame_len)
        return -1;

    if (s->nb_channels == 2) {
397
        s->ms_stereo = get_bits1(&s->gb);
Fabrice Bellard's avatar
Fabrice Bellard committed
398 399 400
    }
    v = 0;
    for(ch = 0; ch < s->nb_channels; ch++) {
401
        a = get_bits1(&s->gb);
Fabrice Bellard's avatar
Fabrice Bellard committed
402 403 404
        s->channel_coded[ch] = a;
        v |= a;
    }
405 406 407

    bsize = s->frame_len_bits - s->block_len_bits;

Fabrice Bellard's avatar
Fabrice Bellard committed
408 409 410 411 412 413 414 415 416 417 418 419 420 421
    /* if no channel coded, no need to go further */
    /* XXX: fix potential framing problems */
    if (!v)
        goto next;

    /* read total gain and extract corresponding number of bits for
       coef escape coding */
    total_gain = 1;
    for(;;) {
        a = get_bits(&s->gb, 7);
        total_gain += a;
        if (a != 127)
            break;
    }
422

Michael Niedermayer's avatar
Michael Niedermayer committed
423
    coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
Fabrice Bellard's avatar
Fabrice Bellard committed
424 425 426 427 428 429 430 431 432 433 434 435 436 437

    /* compute number of coefficients */
    n = s->coefs_end[bsize] - s->coefs_start;
    for(ch = 0; ch < s->nb_channels; ch++)
        nb_coefs[ch] = n;

    /* complex coding */
    if (s->use_noise_coding) {

        for(ch = 0; ch < s->nb_channels; ch++) {
            if (s->channel_coded[ch]) {
                int i, n, a;
                n = s->exponent_high_sizes[bsize];
                for(i=0;i<n;i++) {
438
                    a = get_bits1(&s->gb);
Fabrice Bellard's avatar
Fabrice Bellard committed
439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456
                    s->high_band_coded[ch][i] = a;
                    /* if noise coding, the coefficients are not transmitted */
                    if (a)
                        nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
                }
            }
        }
        for(ch = 0; ch < s->nb_channels; ch++) {
            if (s->channel_coded[ch]) {
                int i, n, val, code;

                n = s->exponent_high_sizes[bsize];
                val = (int)0x80000000;
                for(i=0;i<n;i++) {
                    if (s->high_band_coded[ch][i]) {
                        if (val == (int)0x80000000) {
                            val = get_bits(&s->gb, 7) - 19;
                        } else {
457
                            code = get_vlc2(&s->gb, s->hgain_vlc.table, HGAINVLCBITS, HGAINMAX);
Fabrice Bellard's avatar
Fabrice Bellard committed
458 459 460 461 462 463 464 465 466 467
                            if (code < 0)
                                return -1;
                            val += code - 18;
                        }
                        s->high_band_values[ch][i] = val;
                    }
                }
            }
        }
    }
468

469 470
    /* exponents can be reused in short blocks. */
    if ((s->block_len_bits == s->frame_len_bits) ||
471
        get_bits1(&s->gb)) {
Fabrice Bellard's avatar
Fabrice Bellard committed
472 473 474 475 476 477 478 479
        for(ch = 0; ch < s->nb_channels; ch++) {
            if (s->channel_coded[ch]) {
                if (s->use_exp_vlc) {
                    if (decode_exp_vlc(s, ch) < 0)
                        return -1;
                } else {
                    decode_exp_lsp(s, ch);
                }
480
                s->exponents_bsize[ch] = bsize;
Fabrice Bellard's avatar
Fabrice Bellard committed
481 482 483 484 485 486 487 488 489 490
            }
        }
    }

    /* parse spectral coefficients : just RLE encoding */
    for(ch = 0; ch < s->nb_channels; ch++) {
        if (s->channel_coded[ch]) {
            VLC *coef_vlc;
            int level, run, sign, tindex;
            int16_t *ptr, *eptr;
491
            const uint16_t *level_table, *run_table;
Fabrice Bellard's avatar
Fabrice Bellard committed
492 493 494 495 496 497 498 499 500 501 502 503

            /* special VLC tables are used for ms stereo because
               there is potentially less energy there */
            tindex = (ch == 1 && s->ms_stereo);
            coef_vlc = &s->coef_vlc[tindex];
            run_table = s->run_table[tindex];
            level_table = s->level_table[tindex];
            /* XXX: optimize */
            ptr = &s->coefs1[ch][0];
            eptr = ptr + nb_coefs[ch];
            memset(ptr, 0, s->block_len * sizeof(int16_t));
            for(;;) {
504
                code = get_vlc2(&s->gb, coef_vlc->table, VLCBITS, VLCMAX);
Fabrice Bellard's avatar
Fabrice Bellard committed
505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520
                if (code < 0)
                    return -1;
                if (code == 1) {
                    /* EOB */
                    break;
                } else if (code == 0) {
                    /* escape */
                    level = get_bits(&s->gb, coef_nb_bits);
                    /* NOTE: this is rather suboptimal. reading
                       block_len_bits would be better */
                    run = get_bits(&s->gb, s->frame_len_bits);
                } else {
                    /* normal code */
                    run = run_table[code];
                    level = level_table[code];
                }
521
                sign = get_bits1(&s->gb);
Fabrice Bellard's avatar
Fabrice Bellard committed
522 523 524 525
                if (!sign)
                    level = -level;
                ptr += run;
                if (ptr >= eptr)
526 527 528 529
                {
                    av_log(NULL, AV_LOG_ERROR, "overflow in spectral RLE, ignoring\n");
                    break;
                }
Fabrice Bellard's avatar
Fabrice Bellard committed
530 531 532 533 534 535 536 537 538 539
                *ptr++ = level;
                /* NOTE: EOB can be omitted */
                if (ptr >= eptr)
                    break;
            }
        }
        if (s->version == 1 && s->nb_channels >= 2) {
            align_get_bits(&s->gb);
        }
    }
540

Fabrice Bellard's avatar
Fabrice Bellard committed
541 542 543 544 545 546 547 548 549 550 551 552 553
    /* normalize */
    {
        int n4 = s->block_len / 2;
        mdct_norm = 1.0 / (float)n4;
        if (s->version == 1) {
            mdct_norm *= sqrt(n4);
        }
    }

    /* finally compute the MDCT coefficients */
    for(ch = 0; ch < s->nb_channels; ch++) {
        if (s->channel_coded[ch]) {
            int16_t *coefs1;
554 555
            float *coefs, *exponents, mult, mult1, noise;
            int i, j, n, n1, last_high_band, esize;
Fabrice Bellard's avatar
Fabrice Bellard committed
556 557 558 559
            float exp_power[HIGH_BAND_MAX_SIZE];

            coefs1 = s->coefs1[ch];
            exponents = s->exponents[ch];
560
            esize = s->exponents_bsize[ch];
561
            mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
Fabrice Bellard's avatar
Fabrice Bellard committed
562 563 564 565 566 567
            mult *= mdct_norm;
            coefs = s->coefs[ch];
            if (s->use_noise_coding) {
                mult1 = mult;
                /* very low freqs : noise */
                for(i = 0;i < s->coefs_start; i++) {
568 569
                    *coefs++ = s->noise_table[s->noise_index] *
                      exponents[i<<bsize>>esize] * mult1;
Fabrice Bellard's avatar
Fabrice Bellard committed
570 571
                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
                }
572

Fabrice Bellard's avatar
Fabrice Bellard committed
573 574 575
                n1 = s->exponent_high_sizes[bsize];

                /* compute power of high bands */
576 577
                exponents = s->exponents[ch] +
                    (s->high_band_start[bsize]<<bsize);
Fabrice Bellard's avatar
Fabrice Bellard committed
578 579
                last_high_band = 0; /* avoid warning */
                for(j=0;j<n1;j++) {
580
                    n = s->exponent_high_bands[s->frame_len_bits -
Fabrice Bellard's avatar
Fabrice Bellard committed
581 582 583 584 585
                                              s->block_len_bits][j];
                    if (s->high_band_coded[ch][j]) {
                        float e2, v;
                        e2 = 0;
                        for(i = 0;i < n; i++) {
586
                            v = exponents[i<<bsize>>esize];
Fabrice Bellard's avatar
Fabrice Bellard committed
587 588 589 590
                            e2 += v * v;
                        }
                        exp_power[j] = e2 / n;
                        last_high_band = j;
591
                        tprintf(s->avctx, "%d: power=%f (%d)\n", j, exp_power[j], n);
Fabrice Bellard's avatar
Fabrice Bellard committed
592
                    }
593
                    exponents += n<<bsize;
Fabrice Bellard's avatar
Fabrice Bellard committed
594 595 596
                }

                /* main freqs and high freqs */
597
                exponents = s->exponents[ch] + (s->coefs_start<<bsize);
Fabrice Bellard's avatar
Fabrice Bellard committed
598 599
                for(j=-1;j<n1;j++) {
                    if (j < 0) {
600
                        n = s->high_band_start[bsize] -
Fabrice Bellard's avatar
Fabrice Bellard committed
601 602
                            s->coefs_start;
                    } else {
603
                        n = s->exponent_high_bands[s->frame_len_bits -
Fabrice Bellard's avatar
Fabrice Bellard committed
604 605 606 607 608
                                                  s->block_len_bits][j];
                    }
                    if (j >= 0 && s->high_band_coded[ch][j]) {
                        /* use noise with specified power */
                        mult1 = sqrt(exp_power[j] / exp_power[last_high_band]);
609 610
                        /* XXX: use a table */
                        mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05);
Fabrice Bellard's avatar
Fabrice Bellard committed
611 612 613 614 615
                        mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult);
                        mult1 *= mdct_norm;
                        for(i = 0;i < n; i++) {
                            noise = s->noise_table[s->noise_index];
                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
616 617
                            *coefs++ =  noise *
                                exponents[i<<bsize>>esize] * mult1;
Fabrice Bellard's avatar
Fabrice Bellard committed
618
                        }
619
                        exponents += n<<bsize;
Fabrice Bellard's avatar
Fabrice Bellard committed
620 621 622 623 624
                    } else {
                        /* coded values + small noise */
                        for(i = 0;i < n; i++) {
                            noise = s->noise_table[s->noise_index];
                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
625 626
                            *coefs++ = ((*coefs1++) + noise) *
                                exponents[i<<bsize>>esize] * mult;
Fabrice Bellard's avatar
Fabrice Bellard committed
627
                        }
628
                        exponents += n<<bsize;
Fabrice Bellard's avatar
Fabrice Bellard committed
629 630 631 632 633
                    }
                }

                /* very high freqs : noise */
                n = s->block_len - s->coefs_end[bsize];
634
                mult1 = mult * exponents[((-1<<bsize))>>esize];
Fabrice Bellard's avatar
Fabrice Bellard committed
635 636 637 638 639 640 641 642 643 644
                for(i = 0; i < n; i++) {
                    *coefs++ = s->noise_table[s->noise_index] * mult1;
                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
                }
            } else {
                /* XXX: optimize more */
                for(i = 0;i < s->coefs_start; i++)
                    *coefs++ = 0.0;
                n = nb_coefs[ch];
                for(i = 0;i < n; i++) {
645
                    *coefs++ = coefs1[i] * exponents[i<<bsize>>esize] * mult;
Fabrice Bellard's avatar
Fabrice Bellard committed
646 647 648 649 650 651 652 653
                }
                n = s->block_len - s->coefs_end[bsize];
                for(i = 0;i < n; i++)
                    *coefs++ = 0.0;
            }
        }
    }

654
#ifdef TRACE
Fabrice Bellard's avatar
Fabrice Bellard committed
655 656
    for(ch = 0; ch < s->nb_channels; ch++) {
        if (s->channel_coded[ch]) {
657 658
            dump_floats(s, "exponents", 3, s->exponents[ch], s->block_len);
            dump_floats(s, "coefs", 1, s->coefs[ch], s->block_len);
Fabrice Bellard's avatar
Fabrice Bellard committed
659 660 661
        }
    }
#endif
662

Fabrice Bellard's avatar
Fabrice Bellard committed
663 664 665 666 667 668 669 670
    if (s->ms_stereo && s->channel_coded[1]) {
        float a, b;
        int i;

        /* nominal case for ms stereo: we do it before mdct */
        /* no need to optimize this case because it should almost
           never happen */
        if (!s->channel_coded[0]) {
671
            tprintf(s->avctx, "rare ms-stereo case happened\n");
Fabrice Bellard's avatar
Fabrice Bellard committed
672 673 674
            memset(s->coefs[0], 0, sizeof(float) * s->block_len);
            s->channel_coded[0] = 1;
        }
675

Fabrice Bellard's avatar
Fabrice Bellard committed
676 677 678 679 680 681 682 683
        for(i = 0; i < s->block_len; i++) {
            a = s->coefs[0][i];
            b = s->coefs[1][i];
            s->coefs[0][i] = a + b;
            s->coefs[1][i] = a - b;
        }
    }

684
next:
Fabrice Bellard's avatar
Fabrice Bellard committed
685
    for(ch = 0; ch < s->nb_channels; ch++) {
Michael Niedermayer's avatar
Michael Niedermayer committed
686
        int n4, index, n;
Fabrice Bellard's avatar
Fabrice Bellard committed
687

Michael Niedermayer's avatar
Michael Niedermayer committed
688 689 690
        n = s->block_len;
        n4 = s->block_len / 2;
        if(s->channel_coded[ch]){
691
            ff_imdct_calc(&s->mdct_ctx[bsize], s->output, s->coefs[ch]);
Michael Niedermayer's avatar
Michael Niedermayer committed
692 693 694 695 696 697 698 699 700 701 702 703
        }else
            memset(s->output, 0, sizeof(s->output));

        /* multiply by the window and add in the frame */
        index = (s->frame_len / 2) + s->block_pos - n4;
        wma_window(s, &s->frame_out[ch][index]);

        /* specific fast case for ms-stereo : add to second
            channel if it is not coded */
        if (s->ms_stereo && !s->channel_coded[1]) {
            wma_window(s, &s->frame_out[1][index]);
        }
Fabrice Bellard's avatar
Fabrice Bellard committed
704
    }
705

Fabrice Bellard's avatar
Fabrice Bellard committed
706 707 708 709 710 711 712 713 714 715
    /* update block number */
    s->block_num++;
    s->block_pos += s->block_len;
    if (s->block_pos >= s->frame_len)
        return 1;
    else
        return 0;
}

/* decode a frame of frame_len samples */
716
static int wma_decode_frame(WMACodecContext *s, int16_t *samples)
Fabrice Bellard's avatar
Fabrice Bellard committed
717
{
718
    int ret, i, n, ch, incr;
Fabrice Bellard's avatar
Fabrice Bellard committed
719 720 721
    int16_t *ptr;
    float *iptr;

722
#ifdef TRACE
723
    tprintf(s->avctx, "***decode_frame: %d size=%d\n", s->frame_count++, s->frame_len);
724
#endif
Fabrice Bellard's avatar
Fabrice Bellard committed
725 726 727 728 729 730

    /* read each block */
    s->block_num = 0;
    s->block_pos = 0;
    for(;;) {
        ret = wma_decode_block(s);
731
        if (ret < 0)
Fabrice Bellard's avatar
Fabrice Bellard committed
732 733 734 735 736 737 738 739 740 741 742 743 744
            return -1;
        if (ret)
            break;
    }

    /* convert frame to integer */
    n = s->frame_len;
    incr = s->nb_channels;
    for(ch = 0; ch < s->nb_channels; ch++) {
        ptr = samples + ch;
        iptr = s->frame_out[ch];

        for(i=0;i<n;i++) {
745
            *ptr = av_clip_int16(lrintf(*iptr++));
Fabrice Bellard's avatar
Fabrice Bellard committed
746 747 748 749 750 751 752
            ptr += incr;
        }
        /* prepare for next block */
        memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
                s->frame_len * sizeof(float));
    }

753
#ifdef TRACE
754
    dump_shorts(s, "samples", samples, n * s->nb_channels);
Fabrice Bellard's avatar
Fabrice Bellard committed
755 756 757 758
#endif
    return 0;
}

759
static int wma_decode_superframe(AVCodecContext *avctx,
Fabrice Bellard's avatar
Fabrice Bellard committed
760
                                 void *data, int *data_size,
Michael Niedermayer's avatar
Michael Niedermayer committed
761
                                 const uint8_t *buf, int buf_size)
Fabrice Bellard's avatar
Fabrice Bellard committed
762
{
763
    WMACodecContext *s = avctx->priv_data;
Fabrice Bellard's avatar
Fabrice Bellard committed
764 765 766
    int nb_frames, bit_offset, i, pos, len;
    uint8_t *q;
    int16_t *samples;
767

768
    tprintf(avctx, "***decode_superframe:\n");
Fabrice Bellard's avatar
Fabrice Bellard committed
769

Michael Niedermayer's avatar
Michael Niedermayer committed
770 771 772 773
    if(buf_size==0){
        s->last_superframe_len = 0;
        return 0;
    }
774 775 776
    if (buf_size < s->block_align)
        return 0;
    buf_size = s->block_align;
777

Fabrice Bellard's avatar
Fabrice Bellard committed
778 779
    samples = data;

780
    init_get_bits(&s->gb, buf, buf_size*8);
781

Fabrice Bellard's avatar
Fabrice Bellard committed
782 783
    if (s->use_bit_reservoir) {
        /* read super frame header */
784
        skip_bits(&s->gb, 4); /* super frame index */
Fabrice Bellard's avatar
Fabrice Bellard committed
785 786
        nb_frames = get_bits(&s->gb, 4) - 1;

787 788 789 790 791
        if((nb_frames+1) * s->nb_channels * s->frame_len * sizeof(int16_t) > *data_size){
            av_log(s->avctx, AV_LOG_ERROR, "Insufficient output space\n");
            goto fail;
        }

Fabrice Bellard's avatar
Fabrice Bellard committed
792 793 794 795 796
        bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);

        if (s->last_superframe_len > 0) {
            //        printf("skip=%d\n", s->last_bitoffset);
            /* add bit_offset bits to last frame */
797
            if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
Fabrice Bellard's avatar
Fabrice Bellard committed
798
                MAX_CODED_SUPERFRAME_SIZE)
799
                goto fail;
Fabrice Bellard's avatar
Fabrice Bellard committed
800 801
            q = s->last_superframe + s->last_superframe_len;
            len = bit_offset;
802
            while (len > 7) {
Fabrice Bellard's avatar
Fabrice Bellard committed
803 804 805 806 807 808
                *q++ = (get_bits)(&s->gb, 8);
                len -= 8;
            }
            if (len > 0) {
                *q++ = (get_bits)(&s->gb, len) << (8 - len);
            }
809

Fabrice Bellard's avatar
Fabrice Bellard committed
810
            /* XXX: bit_offset bits into last frame */
811
            init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE*8);
Fabrice Bellard's avatar
Fabrice Bellard committed
812 813 814 815 816 817
            /* skip unused bits */
            if (s->last_bitoffset > 0)
                skip_bits(&s->gb, s->last_bitoffset);
            /* this frame is stored in the last superframe and in the
               current one */
            if (wma_decode_frame(s, samples) < 0)
818
                goto fail;
Fabrice Bellard's avatar
Fabrice Bellard committed
819 820 821 822 823
            samples += s->nb_channels * s->frame_len;
        }

        /* read each frame starting from bit_offset */
        pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
824
        init_get_bits(&s->gb, buf + (pos >> 3), (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3))*8);
Fabrice Bellard's avatar
Fabrice Bellard committed
825 826 827
        len = pos & 7;
        if (len > 0)
            skip_bits(&s->gb, len);
828

Fabrice Bellard's avatar
Fabrice Bellard committed
829 830 831
        s->reset_block_lengths = 1;
        for(i=0;i<nb_frames;i++) {
            if (wma_decode_frame(s, samples) < 0)
832
                goto fail;
Fabrice Bellard's avatar
Fabrice Bellard committed
833 834 835 836 837 838 839 840
            samples += s->nb_channels * s->frame_len;
        }

        /* we copy the end of the frame in the last frame buffer */
        pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
        s->last_bitoffset = pos & 7;
        pos >>= 3;
        len = buf_size - pos;
841
        if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
842
            goto fail;
Fabrice Bellard's avatar
Fabrice Bellard committed
843 844 845 846
        }
        s->last_superframe_len = len;
        memcpy(s->last_superframe, buf + pos, len);
    } else {
847 848 849 850
        if(s->nb_channels * s->frame_len * sizeof(int16_t) > *data_size){
            av_log(s->avctx, AV_LOG_ERROR, "Insufficient output space\n");
            goto fail;
        }
Fabrice Bellard's avatar
Fabrice Bellard committed
851 852
        /* single frame decode */
        if (wma_decode_frame(s, samples) < 0)
853
            goto fail;
Fabrice Bellard's avatar
Fabrice Bellard committed
854 855
        samples += s->nb_channels * s->frame_len;
    }
Michael Niedermayer's avatar
Michael Niedermayer committed
856 857 858

//av_log(NULL, AV_LOG_ERROR, "%d %d %d %d outbytes:%d eaten:%d\n", s->frame_len_bits, s->block_len_bits, s->frame_len, s->block_len,        (int8_t *)samples - (int8_t *)data, s->block_align);

Fabrice Bellard's avatar
Fabrice Bellard committed
859 860
    *data_size = (int8_t *)samples - (int8_t *)data;
    return s->block_align;
861 862 863 864
 fail:
    /* when error, we reset the bit reservoir */
    s->last_superframe_len = 0;
    return -1;
Fabrice Bellard's avatar
Fabrice Bellard committed
865 866 867 868 869 870 871
}

AVCodec wmav1_decoder =
{
    "wmav1",
    CODEC_TYPE_AUDIO,
    CODEC_ID_WMAV1,
872
    sizeof(WMACodecContext),
Fabrice Bellard's avatar
Fabrice Bellard committed
873 874
    wma_decode_init,
    NULL,
Michael Niedermayer's avatar
Michael Niedermayer committed
875
    ff_wma_end,
Fabrice Bellard's avatar
Fabrice Bellard committed
876
    wma_decode_superframe,
877
    .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"),
Fabrice Bellard's avatar
Fabrice Bellard committed
878 879 880 881 882 883 884
};

AVCodec wmav2_decoder =
{
    "wmav2",
    CODEC_TYPE_AUDIO,
    CODEC_ID_WMAV2,
885
    sizeof(WMACodecContext),
Fabrice Bellard's avatar
Fabrice Bellard committed
886 887
    wma_decode_init,
    NULL,
Michael Niedermayer's avatar
Michael Niedermayer committed
888
    ff_wma_end,
Fabrice Bellard's avatar
Fabrice Bellard committed
889
    wma_decode_superframe,
890
    .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"),
Fabrice Bellard's avatar
Fabrice Bellard committed
891
};