Libav
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00001 /* 00002 * WMA compatible decoder 00003 * Copyright (c) 2002 The FFmpeg Project 00004 * 00005 * This file is part of FFmpeg. 00006 * 00007 * FFmpeg is free software; you can redistribute it and/or 00008 * modify it under the terms of the GNU Lesser General Public 00009 * License as published by the Free Software Foundation; either 00010 * version 2.1 of the License, or (at your option) any later version. 00011 * 00012 * FFmpeg is distributed in the hope that it will be useful, 00013 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00015 * Lesser General Public License for more details. 00016 * 00017 * You should have received a copy of the GNU Lesser General Public 00018 * License along with FFmpeg; if not, write to the Free Software 00019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00020 */ 00021 00036 #include "avcodec.h" 00037 #include "wma.h" 00038 00039 #undef NDEBUG 00040 #include <assert.h> 00041 00042 #define EXPVLCBITS 8 00043 #define EXPMAX ((19+EXPVLCBITS-1)/EXPVLCBITS) 00044 00045 #define HGAINVLCBITS 9 00046 #define HGAINMAX ((13+HGAINVLCBITS-1)/HGAINVLCBITS) 00047 00048 static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len); 00049 00050 #ifdef TRACE 00051 static void dump_shorts(WMACodecContext *s, const char *name, const short *tab, int n) 00052 { 00053 int i; 00054 00055 tprintf(s->avctx, "%s[%d]:\n", name, n); 00056 for(i=0;i<n;i++) { 00057 if ((i & 7) == 0) 00058 tprintf(s->avctx, "%4d: ", i); 00059 tprintf(s->avctx, " %5d.0", tab[i]); 00060 if ((i & 7) == 7) 00061 tprintf(s->avctx, "\n"); 00062 } 00063 } 00064 00065 static void dump_floats(WMACodecContext *s, const char *name, int prec, const float *tab, int n) 00066 { 00067 int i; 00068 00069 tprintf(s->avctx, "%s[%d]:\n", name, n); 00070 for(i=0;i<n;i++) { 00071 if ((i & 7) == 0) 00072 tprintf(s->avctx, "%4d: ", i); 00073 tprintf(s->avctx, " %8.*f", prec, tab[i]); 00074 if ((i & 7) == 7) 00075 tprintf(s->avctx, "\n"); 00076 } 00077 if ((i & 7) != 0) 00078 tprintf(s->avctx, "\n"); 00079 } 00080 #endif 00081 00082 static int wma_decode_init(AVCodecContext * avctx) 00083 { 00084 WMACodecContext *s = avctx->priv_data; 00085 int i, flags2; 00086 uint8_t *extradata; 00087 00088 s->avctx = avctx; 00089 00090 /* extract flag infos */ 00091 flags2 = 0; 00092 extradata = avctx->extradata; 00093 if (avctx->codec->id == CODEC_ID_WMAV1 && avctx->extradata_size >= 4) { 00094 flags2 = AV_RL16(extradata+2); 00095 } else if (avctx->codec->id == CODEC_ID_WMAV2 && avctx->extradata_size >= 6) { 00096 flags2 = AV_RL16(extradata+4); 00097 } 00098 // for(i=0; i<avctx->extradata_size; i++) 00099 // av_log(NULL, AV_LOG_ERROR, "%02X ", extradata[i]); 00100 00101 s->use_exp_vlc = flags2 & 0x0001; 00102 s->use_bit_reservoir = flags2 & 0x0002; 00103 s->use_variable_block_len = flags2 & 0x0004; 00104 00105 if(ff_wma_init(avctx, flags2)<0) 00106 return -1; 00107 00108 /* init MDCT */ 00109 for(i = 0; i < s->nb_block_sizes; i++) 00110 ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1, 1.0); 00111 00112 if (s->use_noise_coding) { 00113 init_vlc(&s->hgain_vlc, HGAINVLCBITS, sizeof(ff_wma_hgain_huffbits), 00114 ff_wma_hgain_huffbits, 1, 1, 00115 ff_wma_hgain_huffcodes, 2, 2, 0); 00116 } 00117 00118 if (s->use_exp_vlc) { 00119 init_vlc(&s->exp_vlc, EXPVLCBITS, sizeof(ff_aac_scalefactor_bits), //FIXME move out of context 00120 ff_aac_scalefactor_bits, 1, 1, 00121 ff_aac_scalefactor_code, 4, 4, 0); 00122 } else { 00123 wma_lsp_to_curve_init(s, s->frame_len); 00124 } 00125 00126 avctx->sample_fmt = SAMPLE_FMT_S16; 00127 return 0; 00128 } 00129 00136 static inline float pow_m1_4(WMACodecContext *s, float x) 00137 { 00138 union { 00139 float f; 00140 unsigned int v; 00141 } u, t; 00142 unsigned int e, m; 00143 float a, b; 00144 00145 u.f = x; 00146 e = u.v >> 23; 00147 m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1); 00148 /* build interpolation scale: 1 <= t < 2. */ 00149 t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23); 00150 a = s->lsp_pow_m_table1[m]; 00151 b = s->lsp_pow_m_table2[m]; 00152 return s->lsp_pow_e_table[e] * (a + b * t.f); 00153 } 00154 00155 static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len) 00156 { 00157 float wdel, a, b; 00158 int i, e, m; 00159 00160 wdel = M_PI / frame_len; 00161 for(i=0;i<frame_len;i++) 00162 s->lsp_cos_table[i] = 2.0f * cos(wdel * i); 00163 00164 /* tables for x^-0.25 computation */ 00165 for(i=0;i<256;i++) { 00166 e = i - 126; 00167 s->lsp_pow_e_table[i] = pow(2.0, e * -0.25); 00168 } 00169 00170 /* NOTE: these two tables are needed to avoid two operations in 00171 pow_m1_4 */ 00172 b = 1.0; 00173 for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) { 00174 m = (1 << LSP_POW_BITS) + i; 00175 a = (float)m * (0.5 / (1 << LSP_POW_BITS)); 00176 a = pow(a, -0.25); 00177 s->lsp_pow_m_table1[i] = 2 * a - b; 00178 s->lsp_pow_m_table2[i] = b - a; 00179 b = a; 00180 } 00181 #if 0 00182 for(i=1;i<20;i++) { 00183 float v, r1, r2; 00184 v = 5.0 / i; 00185 r1 = pow_m1_4(s, v); 00186 r2 = pow(v,-0.25); 00187 printf("%f^-0.25=%f e=%f\n", v, r1, r2 - r1); 00188 } 00189 #endif 00190 } 00191 00196 static void wma_lsp_to_curve(WMACodecContext *s, 00197 float *out, float *val_max_ptr, 00198 int n, float *lsp) 00199 { 00200 int i, j; 00201 float p, q, w, v, val_max; 00202 00203 val_max = 0; 00204 for(i=0;i<n;i++) { 00205 p = 0.5f; 00206 q = 0.5f; 00207 w = s->lsp_cos_table[i]; 00208 for(j=1;j<NB_LSP_COEFS;j+=2){ 00209 q *= w - lsp[j - 1]; 00210 p *= w - lsp[j]; 00211 } 00212 p *= p * (2.0f - w); 00213 q *= q * (2.0f + w); 00214 v = p + q; 00215 v = pow_m1_4(s, v); 00216 if (v > val_max) 00217 val_max = v; 00218 out[i] = v; 00219 } 00220 *val_max_ptr = val_max; 00221 } 00222 00226 static void decode_exp_lsp(WMACodecContext *s, int ch) 00227 { 00228 float lsp_coefs[NB_LSP_COEFS]; 00229 int val, i; 00230 00231 for(i = 0; i < NB_LSP_COEFS; i++) { 00232 if (i == 0 || i >= 8) 00233 val = get_bits(&s->gb, 3); 00234 else 00235 val = get_bits(&s->gb, 4); 00236 lsp_coefs[i] = ff_wma_lsp_codebook[i][val]; 00237 } 00238 00239 wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch], 00240 s->block_len, lsp_coefs); 00241 } 00242 00244 static const float pow_tab[] = { 00245 1.7782794100389e-04, 2.0535250264571e-04, 00246 2.3713737056617e-04, 2.7384196342644e-04, 00247 3.1622776601684e-04, 3.6517412725484e-04, 00248 4.2169650342858e-04, 4.8696752516586e-04, 00249 5.6234132519035e-04, 6.4938163157621e-04, 00250 7.4989420933246e-04, 8.6596432336006e-04, 00251 1.0000000000000e-03, 1.1547819846895e-03, 00252 1.3335214321633e-03, 1.5399265260595e-03, 00253 1.7782794100389e-03, 2.0535250264571e-03, 00254 2.3713737056617e-03, 2.7384196342644e-03, 00255 3.1622776601684e-03, 3.6517412725484e-03, 00256 4.2169650342858e-03, 4.8696752516586e-03, 00257 5.6234132519035e-03, 6.4938163157621e-03, 00258 7.4989420933246e-03, 8.6596432336006e-03, 00259 1.0000000000000e-02, 1.1547819846895e-02, 00260 1.3335214321633e-02, 1.5399265260595e-02, 00261 1.7782794100389e-02, 2.0535250264571e-02, 00262 2.3713737056617e-02, 2.7384196342644e-02, 00263 3.1622776601684e-02, 3.6517412725484e-02, 00264 4.2169650342858e-02, 4.8696752516586e-02, 00265 5.6234132519035e-02, 6.4938163157621e-02, 00266 7.4989420933246e-02, 8.6596432336007e-02, 00267 1.0000000000000e-01, 1.1547819846895e-01, 00268 1.3335214321633e-01, 1.5399265260595e-01, 00269 1.7782794100389e-01, 2.0535250264571e-01, 00270 2.3713737056617e-01, 2.7384196342644e-01, 00271 3.1622776601684e-01, 3.6517412725484e-01, 00272 4.2169650342858e-01, 4.8696752516586e-01, 00273 5.6234132519035e-01, 6.4938163157621e-01, 00274 7.4989420933246e-01, 8.6596432336007e-01, 00275 1.0000000000000e+00, 1.1547819846895e+00, 00276 1.3335214321633e+00, 1.5399265260595e+00, 00277 1.7782794100389e+00, 2.0535250264571e+00, 00278 2.3713737056617e+00, 2.7384196342644e+00, 00279 3.1622776601684e+00, 3.6517412725484e+00, 00280 4.2169650342858e+00, 4.8696752516586e+00, 00281 5.6234132519035e+00, 6.4938163157621e+00, 00282 7.4989420933246e+00, 8.6596432336007e+00, 00283 1.0000000000000e+01, 1.1547819846895e+01, 00284 1.3335214321633e+01, 1.5399265260595e+01, 00285 1.7782794100389e+01, 2.0535250264571e+01, 00286 2.3713737056617e+01, 2.7384196342644e+01, 00287 3.1622776601684e+01, 3.6517412725484e+01, 00288 4.2169650342858e+01, 4.8696752516586e+01, 00289 5.6234132519035e+01, 6.4938163157621e+01, 00290 7.4989420933246e+01, 8.6596432336007e+01, 00291 1.0000000000000e+02, 1.1547819846895e+02, 00292 1.3335214321633e+02, 1.5399265260595e+02, 00293 1.7782794100389e+02, 2.0535250264571e+02, 00294 2.3713737056617e+02, 2.7384196342644e+02, 00295 3.1622776601684e+02, 3.6517412725484e+02, 00296 4.2169650342858e+02, 4.8696752516586e+02, 00297 5.6234132519035e+02, 6.4938163157621e+02, 00298 7.4989420933246e+02, 8.6596432336007e+02, 00299 1.0000000000000e+03, 1.1547819846895e+03, 00300 1.3335214321633e+03, 1.5399265260595e+03, 00301 1.7782794100389e+03, 2.0535250264571e+03, 00302 2.3713737056617e+03, 2.7384196342644e+03, 00303 3.1622776601684e+03, 3.6517412725484e+03, 00304 4.2169650342858e+03, 4.8696752516586e+03, 00305 5.6234132519035e+03, 6.4938163157621e+03, 00306 7.4989420933246e+03, 8.6596432336007e+03, 00307 1.0000000000000e+04, 1.1547819846895e+04, 00308 1.3335214321633e+04, 1.5399265260595e+04, 00309 1.7782794100389e+04, 2.0535250264571e+04, 00310 2.3713737056617e+04, 2.7384196342644e+04, 00311 3.1622776601684e+04, 3.6517412725484e+04, 00312 4.2169650342858e+04, 4.8696752516586e+04, 00313 5.6234132519035e+04, 6.4938163157621e+04, 00314 7.4989420933246e+04, 8.6596432336007e+04, 00315 1.0000000000000e+05, 1.1547819846895e+05, 00316 1.3335214321633e+05, 1.5399265260595e+05, 00317 1.7782794100389e+05, 2.0535250264571e+05, 00318 2.3713737056617e+05, 2.7384196342644e+05, 00319 3.1622776601684e+05, 3.6517412725484e+05, 00320 4.2169650342858e+05, 4.8696752516586e+05, 00321 5.6234132519035e+05, 6.4938163157621e+05, 00322 7.4989420933246e+05, 8.6596432336007e+05, 00323 }; 00324 00328 static int decode_exp_vlc(WMACodecContext *s, int ch) 00329 { 00330 int last_exp, n, code; 00331 const uint16_t *ptr; 00332 float v, max_scale; 00333 uint32_t *q, *q_end, iv; 00334 const float *ptab = pow_tab + 60; 00335 const uint32_t *iptab = (const uint32_t*)ptab; 00336 00337 ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits]; 00338 q = (uint32_t *)s->exponents[ch]; 00339 q_end = q + s->block_len; 00340 max_scale = 0; 00341 if (s->version == 1) { 00342 last_exp = get_bits(&s->gb, 5) + 10; 00343 v = ptab[last_exp]; 00344 iv = iptab[last_exp]; 00345 max_scale = v; 00346 n = *ptr++; 00347 switch (n & 3) do { 00348 case 0: *q++ = iv; 00349 case 3: *q++ = iv; 00350 case 2: *q++ = iv; 00351 case 1: *q++ = iv; 00352 } while ((n -= 4) > 0); 00353 }else 00354 last_exp = 36; 00355 00356 while (q < q_end) { 00357 code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX); 00358 if (code < 0){ 00359 av_log(s->avctx, AV_LOG_ERROR, "Exponent vlc invalid\n"); 00360 return -1; 00361 } 00362 /* NOTE: this offset is the same as MPEG4 AAC ! */ 00363 last_exp += code - 60; 00364 if ((unsigned)last_exp + 60 > FF_ARRAY_ELEMS(pow_tab)) { 00365 av_log(s->avctx, AV_LOG_ERROR, "Exponent out of range: %d\n", 00366 last_exp); 00367 return -1; 00368 } 00369 v = ptab[last_exp]; 00370 iv = iptab[last_exp]; 00371 if (v > max_scale) 00372 max_scale = v; 00373 n = *ptr++; 00374 switch (n & 3) do { 00375 case 0: *q++ = iv; 00376 case 3: *q++ = iv; 00377 case 2: *q++ = iv; 00378 case 1: *q++ = iv; 00379 } while ((n -= 4) > 0); 00380 } 00381 s->max_exponent[ch] = max_scale; 00382 return 0; 00383 } 00384 00385 00392 static void wma_window(WMACodecContext *s, float *out) 00393 { 00394 float *in = s->output; 00395 int block_len, bsize, n; 00396 00397 /* left part */ 00398 if (s->block_len_bits <= s->prev_block_len_bits) { 00399 block_len = s->block_len; 00400 bsize = s->frame_len_bits - s->block_len_bits; 00401 00402 s->dsp.vector_fmul_add(out, in, s->windows[bsize], 00403 out, block_len); 00404 00405 } else { 00406 block_len = 1 << s->prev_block_len_bits; 00407 n = (s->block_len - block_len) / 2; 00408 bsize = s->frame_len_bits - s->prev_block_len_bits; 00409 00410 s->dsp.vector_fmul_add(out+n, in+n, s->windows[bsize], 00411 out+n, block_len); 00412 00413 memcpy(out+n+block_len, in+n+block_len, n*sizeof(float)); 00414 } 00415 00416 out += s->block_len; 00417 in += s->block_len; 00418 00419 /* right part */ 00420 if (s->block_len_bits <= s->next_block_len_bits) { 00421 block_len = s->block_len; 00422 bsize = s->frame_len_bits - s->block_len_bits; 00423 00424 s->dsp.vector_fmul_reverse(out, in, s->windows[bsize], block_len); 00425 00426 } else { 00427 block_len = 1 << s->next_block_len_bits; 00428 n = (s->block_len - block_len) / 2; 00429 bsize = s->frame_len_bits - s->next_block_len_bits; 00430 00431 memcpy(out, in, n*sizeof(float)); 00432 00433 s->dsp.vector_fmul_reverse(out+n, in+n, s->windows[bsize], block_len); 00434 00435 memset(out+n+block_len, 0, n*sizeof(float)); 00436 } 00437 } 00438 00439 00444 static int wma_decode_block(WMACodecContext *s) 00445 { 00446 int n, v, a, ch, bsize; 00447 int coef_nb_bits, total_gain; 00448 int nb_coefs[MAX_CHANNELS]; 00449 float mdct_norm; 00450 00451 #ifdef TRACE 00452 tprintf(s->avctx, "***decode_block: %d:%d\n", s->frame_count - 1, s->block_num); 00453 #endif 00454 00455 /* compute current block length */ 00456 if (s->use_variable_block_len) { 00457 n = av_log2(s->nb_block_sizes - 1) + 1; 00458 00459 if (s->reset_block_lengths) { 00460 s->reset_block_lengths = 0; 00461 v = get_bits(&s->gb, n); 00462 if (v >= s->nb_block_sizes){ 00463 av_log(s->avctx, AV_LOG_ERROR, "prev_block_len_bits %d out of range\n", s->frame_len_bits - v); 00464 return -1; 00465 } 00466 s->prev_block_len_bits = s->frame_len_bits - v; 00467 v = get_bits(&s->gb, n); 00468 if (v >= s->nb_block_sizes){ 00469 av_log(s->avctx, AV_LOG_ERROR, "block_len_bits %d out of range\n", s->frame_len_bits - v); 00470 return -1; 00471 } 00472 s->block_len_bits = s->frame_len_bits - v; 00473 } else { 00474 /* update block lengths */ 00475 s->prev_block_len_bits = s->block_len_bits; 00476 s->block_len_bits = s->next_block_len_bits; 00477 } 00478 v = get_bits(&s->gb, n); 00479 if (v >= s->nb_block_sizes){ 00480 av_log(s->avctx, AV_LOG_ERROR, "next_block_len_bits %d out of range\n", s->frame_len_bits - v); 00481 return -1; 00482 } 00483 s->next_block_len_bits = s->frame_len_bits - v; 00484 } else { 00485 /* fixed block len */ 00486 s->next_block_len_bits = s->frame_len_bits; 00487 s->prev_block_len_bits = s->frame_len_bits; 00488 s->block_len_bits = s->frame_len_bits; 00489 } 00490 00491 /* now check if the block length is coherent with the frame length */ 00492 s->block_len = 1 << s->block_len_bits; 00493 if ((s->block_pos + s->block_len) > s->frame_len){ 00494 av_log(s->avctx, AV_LOG_ERROR, "frame_len overflow\n"); 00495 return -1; 00496 } 00497 00498 if (s->nb_channels == 2) { 00499 s->ms_stereo = get_bits1(&s->gb); 00500 } 00501 v = 0; 00502 for(ch = 0; ch < s->nb_channels; ch++) { 00503 a = get_bits1(&s->gb); 00504 s->channel_coded[ch] = a; 00505 v |= a; 00506 } 00507 00508 bsize = s->frame_len_bits - s->block_len_bits; 00509 00510 /* if no channel coded, no need to go further */ 00511 /* XXX: fix potential framing problems */ 00512 if (!v) 00513 goto next; 00514 00515 /* read total gain and extract corresponding number of bits for 00516 coef escape coding */ 00517 total_gain = 1; 00518 for(;;) { 00519 a = get_bits(&s->gb, 7); 00520 total_gain += a; 00521 if (a != 127) 00522 break; 00523 } 00524 00525 coef_nb_bits= ff_wma_total_gain_to_bits(total_gain); 00526 00527 /* compute number of coefficients */ 00528 n = s->coefs_end[bsize] - s->coefs_start; 00529 for(ch = 0; ch < s->nb_channels; ch++) 00530 nb_coefs[ch] = n; 00531 00532 /* complex coding */ 00533 if (s->use_noise_coding) { 00534 00535 for(ch = 0; ch < s->nb_channels; ch++) { 00536 if (s->channel_coded[ch]) { 00537 int i, n, a; 00538 n = s->exponent_high_sizes[bsize]; 00539 for(i=0;i<n;i++) { 00540 a = get_bits1(&s->gb); 00541 s->high_band_coded[ch][i] = a; 00542 /* if noise coding, the coefficients are not transmitted */ 00543 if (a) 00544 nb_coefs[ch] -= s->exponent_high_bands[bsize][i]; 00545 } 00546 } 00547 } 00548 for(ch = 0; ch < s->nb_channels; ch++) { 00549 if (s->channel_coded[ch]) { 00550 int i, n, val, code; 00551 00552 n = s->exponent_high_sizes[bsize]; 00553 val = (int)0x80000000; 00554 for(i=0;i<n;i++) { 00555 if (s->high_band_coded[ch][i]) { 00556 if (val == (int)0x80000000) { 00557 val = get_bits(&s->gb, 7) - 19; 00558 } else { 00559 code = get_vlc2(&s->gb, s->hgain_vlc.table, HGAINVLCBITS, HGAINMAX); 00560 if (code < 0){ 00561 av_log(s->avctx, AV_LOG_ERROR, "hgain vlc invalid\n"); 00562 return -1; 00563 } 00564 val += code - 18; 00565 } 00566 s->high_band_values[ch][i] = val; 00567 } 00568 } 00569 } 00570 } 00571 } 00572 00573 /* exponents can be reused in short blocks. */ 00574 if ((s->block_len_bits == s->frame_len_bits) || 00575 get_bits1(&s->gb)) { 00576 for(ch = 0; ch < s->nb_channels; ch++) { 00577 if (s->channel_coded[ch]) { 00578 if (s->use_exp_vlc) { 00579 if (decode_exp_vlc(s, ch) < 0) 00580 return -1; 00581 } else { 00582 decode_exp_lsp(s, ch); 00583 } 00584 s->exponents_bsize[ch] = bsize; 00585 } 00586 } 00587 } 00588 00589 /* parse spectral coefficients : just RLE encoding */ 00590 for(ch = 0; ch < s->nb_channels; ch++) { 00591 if (s->channel_coded[ch]) { 00592 int tindex; 00593 WMACoef* ptr = &s->coefs1[ch][0]; 00594 00595 /* special VLC tables are used for ms stereo because 00596 there is potentially less energy there */ 00597 tindex = (ch == 1 && s->ms_stereo); 00598 memset(ptr, 0, s->block_len * sizeof(WMACoef)); 00599 ff_wma_run_level_decode(s->avctx, &s->gb, &s->coef_vlc[tindex], 00600 s->level_table[tindex], s->run_table[tindex], 00601 0, ptr, 0, nb_coefs[ch], 00602 s->block_len, s->frame_len_bits, coef_nb_bits); 00603 } 00604 if (s->version == 1 && s->nb_channels >= 2) { 00605 align_get_bits(&s->gb); 00606 } 00607 } 00608 00609 /* normalize */ 00610 { 00611 int n4 = s->block_len / 2; 00612 mdct_norm = 1.0 / (float)n4; 00613 if (s->version == 1) { 00614 mdct_norm *= sqrt(n4); 00615 } 00616 } 00617 00618 /* finally compute the MDCT coefficients */ 00619 for(ch = 0; ch < s->nb_channels; ch++) { 00620 if (s->channel_coded[ch]) { 00621 WMACoef *coefs1; 00622 float *coefs, *exponents, mult, mult1, noise; 00623 int i, j, n, n1, last_high_band, esize; 00624 float exp_power[HIGH_BAND_MAX_SIZE]; 00625 00626 coefs1 = s->coefs1[ch]; 00627 exponents = s->exponents[ch]; 00628 esize = s->exponents_bsize[ch]; 00629 mult = pow(10, total_gain * 0.05) / s->max_exponent[ch]; 00630 mult *= mdct_norm; 00631 coefs = s->coefs[ch]; 00632 if (s->use_noise_coding) { 00633 mult1 = mult; 00634 /* very low freqs : noise */ 00635 for(i = 0;i < s->coefs_start; i++) { 00636 *coefs++ = s->noise_table[s->noise_index] * 00637 exponents[i<<bsize>>esize] * mult1; 00638 s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1); 00639 } 00640 00641 n1 = s->exponent_high_sizes[bsize]; 00642 00643 /* compute power of high bands */ 00644 exponents = s->exponents[ch] + 00645 (s->high_band_start[bsize]<<bsize>>esize); 00646 last_high_band = 0; /* avoid warning */ 00647 for(j=0;j<n1;j++) { 00648 n = s->exponent_high_bands[s->frame_len_bits - 00649 s->block_len_bits][j]; 00650 if (s->high_band_coded[ch][j]) { 00651 float e2, v; 00652 e2 = 0; 00653 for(i = 0;i < n; i++) { 00654 v = exponents[i<<bsize>>esize]; 00655 e2 += v * v; 00656 } 00657 exp_power[j] = e2 / n; 00658 last_high_band = j; 00659 tprintf(s->avctx, "%d: power=%f (%d)\n", j, exp_power[j], n); 00660 } 00661 exponents += n<<bsize>>esize; 00662 } 00663 00664 /* main freqs and high freqs */ 00665 exponents = s->exponents[ch] + (s->coefs_start<<bsize>>esize); 00666 for(j=-1;j<n1;j++) { 00667 if (j < 0) { 00668 n = s->high_band_start[bsize] - 00669 s->coefs_start; 00670 } else { 00671 n = s->exponent_high_bands[s->frame_len_bits - 00672 s->block_len_bits][j]; 00673 } 00674 if (j >= 0 && s->high_band_coded[ch][j]) { 00675 /* use noise with specified power */ 00676 mult1 = sqrt(exp_power[j] / exp_power[last_high_band]); 00677 /* XXX: use a table */ 00678 mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05); 00679 mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult); 00680 mult1 *= mdct_norm; 00681 for(i = 0;i < n; i++) { 00682 noise = s->noise_table[s->noise_index]; 00683 s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1); 00684 *coefs++ = noise * 00685 exponents[i<<bsize>>esize] * mult1; 00686 } 00687 exponents += n<<bsize>>esize; 00688 } else { 00689 /* coded values + small noise */ 00690 for(i = 0;i < n; i++) { 00691 noise = s->noise_table[s->noise_index]; 00692 s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1); 00693 *coefs++ = ((*coefs1++) + noise) * 00694 exponents[i<<bsize>>esize] * mult; 00695 } 00696 exponents += n<<bsize>>esize; 00697 } 00698 } 00699 00700 /* very high freqs : noise */ 00701 n = s->block_len - s->coefs_end[bsize]; 00702 mult1 = mult * exponents[((-1<<bsize))>>esize]; 00703 for(i = 0; i < n; i++) { 00704 *coefs++ = s->noise_table[s->noise_index] * mult1; 00705 s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1); 00706 } 00707 } else { 00708 /* XXX: optimize more */ 00709 for(i = 0;i < s->coefs_start; i++) 00710 *coefs++ = 0.0; 00711 n = nb_coefs[ch]; 00712 for(i = 0;i < n; i++) { 00713 *coefs++ = coefs1[i] * exponents[i<<bsize>>esize] * mult; 00714 } 00715 n = s->block_len - s->coefs_end[bsize]; 00716 for(i = 0;i < n; i++) 00717 *coefs++ = 0.0; 00718 } 00719 } 00720 } 00721 00722 #ifdef TRACE 00723 for(ch = 0; ch < s->nb_channels; ch++) { 00724 if (s->channel_coded[ch]) { 00725 dump_floats(s, "exponents", 3, s->exponents[ch], s->block_len); 00726 dump_floats(s, "coefs", 1, s->coefs[ch], s->block_len); 00727 } 00728 } 00729 #endif 00730 00731 if (s->ms_stereo && s->channel_coded[1]) { 00732 /* nominal case for ms stereo: we do it before mdct */ 00733 /* no need to optimize this case because it should almost 00734 never happen */ 00735 if (!s->channel_coded[0]) { 00736 tprintf(s->avctx, "rare ms-stereo case happened\n"); 00737 memset(s->coefs[0], 0, sizeof(float) * s->block_len); 00738 s->channel_coded[0] = 1; 00739 } 00740 00741 s->dsp.butterflies_float(s->coefs[0], s->coefs[1], s->block_len); 00742 } 00743 00744 next: 00745 for(ch = 0; ch < s->nb_channels; ch++) { 00746 int n4, index; 00747 00748 n4 = s->block_len / 2; 00749 if(s->channel_coded[ch]){ 00750 ff_imdct_calc(&s->mdct_ctx[bsize], s->output, s->coefs[ch]); 00751 }else if(!(s->ms_stereo && ch==1)) 00752 memset(s->output, 0, sizeof(s->output)); 00753 00754 /* multiply by the window and add in the frame */ 00755 index = (s->frame_len / 2) + s->block_pos - n4; 00756 wma_window(s, &s->frame_out[ch][index]); 00757 } 00758 00759 /* update block number */ 00760 s->block_num++; 00761 s->block_pos += s->block_len; 00762 if (s->block_pos >= s->frame_len) 00763 return 1; 00764 else 00765 return 0; 00766 } 00767 00768 /* decode a frame of frame_len samples */ 00769 static int wma_decode_frame(WMACodecContext *s, int16_t *samples) 00770 { 00771 int ret, i, n, ch, incr; 00772 int16_t *ptr; 00773 float *iptr; 00774 00775 #ifdef TRACE 00776 tprintf(s->avctx, "***decode_frame: %d size=%d\n", s->frame_count++, s->frame_len); 00777 #endif 00778 00779 /* read each block */ 00780 s->block_num = 0; 00781 s->block_pos = 0; 00782 for(;;) { 00783 ret = wma_decode_block(s); 00784 if (ret < 0) 00785 return -1; 00786 if (ret) 00787 break; 00788 } 00789 00790 /* convert frame to integer */ 00791 n = s->frame_len; 00792 incr = s->nb_channels; 00793 if (s->dsp.float_to_int16_interleave == ff_float_to_int16_interleave_c) { 00794 for(ch = 0; ch < s->nb_channels; ch++) { 00795 ptr = samples + ch; 00796 iptr = s->frame_out[ch]; 00797 00798 for(i=0;i<n;i++) { 00799 *ptr = av_clip_int16(lrintf(*iptr++)); 00800 ptr += incr; 00801 } 00802 /* prepare for next block */ 00803 memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len], 00804 s->frame_len * sizeof(float)); 00805 } 00806 } else { 00807 float *output[MAX_CHANNELS]; 00808 for (ch = 0; ch < MAX_CHANNELS; ch++) 00809 output[ch] = s->frame_out[ch]; 00810 s->dsp.float_to_int16_interleave(samples, (const float **)output, n, incr); 00811 for(ch = 0; ch < incr; ch++) { 00812 /* prepare for next block */ 00813 memmove(&s->frame_out[ch][0], &s->frame_out[ch][n], n * sizeof(float)); 00814 } 00815 } 00816 00817 #ifdef TRACE 00818 dump_shorts(s, "samples", samples, n * s->nb_channels); 00819 #endif 00820 return 0; 00821 } 00822 00823 static int wma_decode_superframe(AVCodecContext *avctx, 00824 void *data, int *data_size, 00825 AVPacket *avpkt) 00826 { 00827 const uint8_t *buf = avpkt->data; 00828 int buf_size = avpkt->size; 00829 WMACodecContext *s = avctx->priv_data; 00830 int nb_frames, bit_offset, i, pos, len; 00831 uint8_t *q; 00832 int16_t *samples; 00833 00834 tprintf(avctx, "***decode_superframe:\n"); 00835 00836 if(buf_size==0){ 00837 s->last_superframe_len = 0; 00838 return 0; 00839 } 00840 if (buf_size < s->block_align) 00841 return 0; 00842 buf_size = s->block_align; 00843 00844 samples = data; 00845 00846 init_get_bits(&s->gb, buf, buf_size*8); 00847 00848 if (s->use_bit_reservoir) { 00849 /* read super frame header */ 00850 skip_bits(&s->gb, 4); /* super frame index */ 00851 nb_frames = get_bits(&s->gb, 4) - 1; 00852 00853 if((nb_frames+1) * s->nb_channels * s->frame_len * sizeof(int16_t) > *data_size){ 00854 av_log(s->avctx, AV_LOG_ERROR, "Insufficient output space\n"); 00855 goto fail; 00856 } 00857 00858 bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3); 00859 00860 if (s->last_superframe_len > 0) { 00861 // printf("skip=%d\n", s->last_bitoffset); 00862 /* add bit_offset bits to last frame */ 00863 if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) > 00864 MAX_CODED_SUPERFRAME_SIZE) 00865 goto fail; 00866 q = s->last_superframe + s->last_superframe_len; 00867 len = bit_offset; 00868 while (len > 7) { 00869 *q++ = (get_bits)(&s->gb, 8); 00870 len -= 8; 00871 } 00872 if (len > 0) { 00873 *q++ = (get_bits)(&s->gb, len) << (8 - len); 00874 } 00875 00876 /* XXX: bit_offset bits into last frame */ 00877 init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE*8); 00878 /* skip unused bits */ 00879 if (s->last_bitoffset > 0) 00880 skip_bits(&s->gb, s->last_bitoffset); 00881 /* this frame is stored in the last superframe and in the 00882 current one */ 00883 if (wma_decode_frame(s, samples) < 0) 00884 goto fail; 00885 samples += s->nb_channels * s->frame_len; 00886 } 00887 00888 /* read each frame starting from bit_offset */ 00889 pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3; 00890 init_get_bits(&s->gb, buf + (pos >> 3), (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3))*8); 00891 len = pos & 7; 00892 if (len > 0) 00893 skip_bits(&s->gb, len); 00894 00895 s->reset_block_lengths = 1; 00896 for(i=0;i<nb_frames;i++) { 00897 if (wma_decode_frame(s, samples) < 0) 00898 goto fail; 00899 samples += s->nb_channels * s->frame_len; 00900 } 00901 00902 /* we copy the end of the frame in the last frame buffer */ 00903 pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7); 00904 s->last_bitoffset = pos & 7; 00905 pos >>= 3; 00906 len = buf_size - pos; 00907 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) { 00908 av_log(s->avctx, AV_LOG_ERROR, "len %d invalid\n", len); 00909 goto fail; 00910 } 00911 s->last_superframe_len = len; 00912 memcpy(s->last_superframe, buf + pos, len); 00913 } else { 00914 if(s->nb_channels * s->frame_len * sizeof(int16_t) > *data_size){ 00915 av_log(s->avctx, AV_LOG_ERROR, "Insufficient output space\n"); 00916 goto fail; 00917 } 00918 /* single frame decode */ 00919 if (wma_decode_frame(s, samples) < 0) 00920 goto fail; 00921 samples += s->nb_channels * s->frame_len; 00922 } 00923 00924 //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); 00925 00926 *data_size = (int8_t *)samples - (int8_t *)data; 00927 return s->block_align; 00928 fail: 00929 /* when error, we reset the bit reservoir */ 00930 s->last_superframe_len = 0; 00931 return -1; 00932 } 00933 00934 static av_cold void flush(AVCodecContext *avctx) 00935 { 00936 WMACodecContext *s = avctx->priv_data; 00937 00938 s->last_bitoffset= 00939 s->last_superframe_len= 0; 00940 } 00941 00942 AVCodec wmav1_decoder = 00943 { 00944 "wmav1", 00945 AVMEDIA_TYPE_AUDIO, 00946 CODEC_ID_WMAV1, 00947 sizeof(WMACodecContext), 00948 wma_decode_init, 00949 NULL, 00950 ff_wma_end, 00951 wma_decode_superframe, 00952 .flush=flush, 00953 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"), 00954 }; 00955 00956 AVCodec wmav2_decoder = 00957 { 00958 "wmav2", 00959 AVMEDIA_TYPE_AUDIO, 00960 CODEC_ID_WMAV2, 00961 sizeof(WMACodecContext), 00962 wma_decode_init, 00963 NULL, 00964 ff_wma_end, 00965 wma_decode_superframe, 00966 .flush=flush, 00967 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"), 00968 };