FFmpeg: libavcodec/wmadec.c Source File

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(avctx->codec->id == CODEC_ID_WMAV2 && avctx->extradata_size >= 8){
00106         if(AV_RL16(extradata+4)==0xd && s->use_variable_block_len){
00107             av_log(avctx, AV_LOG_WARNING, "Disabling use_variable_block_len, if this fails contact the ffmpeg developers and send us the file\n");
00108             s->use_variable_block_len= 0; // this fixes issue1503
00109         }
00110     }
00111 
00112     if(avctx->channels > MAX_CHANNELS){
00113         av_log(avctx, AV_LOG_ERROR, "Invalid number of channels (%d)\n", avctx->channels);
00114         return -1;
00115     }
00116 
00117     if(ff_wma_init(avctx, flags2)<0)
00118         return -1;
00119 
00120     /* init MDCT */
00121     for(i = 0; i < s->nb_block_sizes; i++)
00122         ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1, 1.0);
00123 
00124     if (s->use_noise_coding) {
00125         init_vlc(&s->hgain_vlc, HGAINVLCBITS, sizeof(ff_wma_hgain_huffbits),
00126                  ff_wma_hgain_huffbits, 1, 1,
00127                  ff_wma_hgain_huffcodes, 2, 2, 0);
00128     }
00129 
00130     if (s->use_exp_vlc) {
00131         init_vlc(&s->exp_vlc, EXPVLCBITS, sizeof(ff_aac_scalefactor_bits), //FIXME move out of context
00132                  ff_aac_scalefactor_bits, 1, 1,
00133                  ff_aac_scalefactor_code, 4, 4, 0);
00134     } else {
00135         wma_lsp_to_curve_init(s, s->frame_len);
00136     }
00137 
00138     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
00139     return 0;
00140 }
00141 
00148 static inline float pow_m1_4(WMACodecContext *s, float x)
00149 {
00150     union {
00151         float f;
00152         unsigned int v;
00153     } u, t;
00154     unsigned int e, m;
00155     float a, b;
00156 
00157     u.f = x;
00158     e = u.v >> 23;
00159     m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
00160     /* build interpolation scale: 1 <= t < 2. */
00161     t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
00162     a = s->lsp_pow_m_table1[m];
00163     b = s->lsp_pow_m_table2[m];
00164     return s->lsp_pow_e_table[e] * (a + b * t.f);
00165 }
00166 
00167 static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len)
00168 {
00169     float wdel, a, b;
00170     int i, e, m;
00171 
00172     wdel = M_PI / frame_len;
00173     for(i=0;i<frame_len;i++)
00174         s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
00175 
00176     /* tables for x^-0.25 computation */
00177     for(i=0;i<256;i++) {
00178         e = i - 126;
00179         s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
00180     }
00181 
00182     /* NOTE: these two tables are needed to avoid two operations in
00183        pow_m1_4 */
00184     b = 1.0;
00185     for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) {
00186         m = (1 << LSP_POW_BITS) + i;
00187         a = (float)m * (0.5 / (1 << LSP_POW_BITS));
00188         a = pow(a, -0.25);
00189         s->lsp_pow_m_table1[i] = 2 * a - b;
00190         s->lsp_pow_m_table2[i] = b - a;
00191         b = a;
00192     }
00193 }
00194 
00199 static void wma_lsp_to_curve(WMACodecContext *s,
00200                              float *out, float *val_max_ptr,
00201                              int n, float *lsp)
00202 {
00203     int i, j;
00204     float p, q, w, v, val_max;
00205 
00206     val_max = 0;
00207     for(i=0;i<n;i++) {
00208         p = 0.5f;
00209         q = 0.5f;
00210         w = s->lsp_cos_table[i];
00211         for(j=1;j<NB_LSP_COEFS;j+=2){
00212             q *= w - lsp[j - 1];
00213             p *= w - lsp[j];
00214         }
00215         p *= p * (2.0f - w);
00216         q *= q * (2.0f + w);
00217         v = p + q;
00218         v = pow_m1_4(s, v);
00219         if (v > val_max)
00220             val_max = v;
00221         out[i] = v;
00222     }
00223     *val_max_ptr = val_max;
00224 }
00225 
00229 static void decode_exp_lsp(WMACodecContext *s, int ch)
00230 {
00231     float lsp_coefs[NB_LSP_COEFS];
00232     int val, i;
00233 
00234     for(i = 0; i < NB_LSP_COEFS; i++) {
00235         if (i == 0 || i >= 8)
00236             val = get_bits(&s->gb, 3);
00237         else
00238             val = get_bits(&s->gb, 4);
00239         lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
00240     }
00241 
00242     wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
00243                      s->block_len, lsp_coefs);
00244 }
00245 
00247 static const float pow_tab[] = {
00248     1.7782794100389e-04, 2.0535250264571e-04,
00249     2.3713737056617e-04, 2.7384196342644e-04,
00250     3.1622776601684e-04, 3.6517412725484e-04,
00251     4.2169650342858e-04, 4.8696752516586e-04,
00252     5.6234132519035e-04, 6.4938163157621e-04,
00253     7.4989420933246e-04, 8.6596432336006e-04,
00254     1.0000000000000e-03, 1.1547819846895e-03,
00255     1.3335214321633e-03, 1.5399265260595e-03,
00256     1.7782794100389e-03, 2.0535250264571e-03,
00257     2.3713737056617e-03, 2.7384196342644e-03,
00258     3.1622776601684e-03, 3.6517412725484e-03,
00259     4.2169650342858e-03, 4.8696752516586e-03,
00260     5.6234132519035e-03, 6.4938163157621e-03,
00261     7.4989420933246e-03, 8.6596432336006e-03,
00262     1.0000000000000e-02, 1.1547819846895e-02,
00263     1.3335214321633e-02, 1.5399265260595e-02,
00264     1.7782794100389e-02, 2.0535250264571e-02,
00265     2.3713737056617e-02, 2.7384196342644e-02,
00266     3.1622776601684e-02, 3.6517412725484e-02,
00267     4.2169650342858e-02, 4.8696752516586e-02,
00268     5.6234132519035e-02, 6.4938163157621e-02,
00269     7.4989420933246e-02, 8.6596432336007e-02,
00270     1.0000000000000e-01, 1.1547819846895e-01,
00271     1.3335214321633e-01, 1.5399265260595e-01,
00272     1.7782794100389e-01, 2.0535250264571e-01,
00273     2.3713737056617e-01, 2.7384196342644e-01,
00274     3.1622776601684e-01, 3.6517412725484e-01,
00275     4.2169650342858e-01, 4.8696752516586e-01,
00276     5.6234132519035e-01, 6.4938163157621e-01,
00277     7.4989420933246e-01, 8.6596432336007e-01,
00278     1.0000000000000e+00, 1.1547819846895e+00,
00279     1.3335214321633e+00, 1.5399265260595e+00,
00280     1.7782794100389e+00, 2.0535250264571e+00,
00281     2.3713737056617e+00, 2.7384196342644e+00,
00282     3.1622776601684e+00, 3.6517412725484e+00,
00283     4.2169650342858e+00, 4.8696752516586e+00,
00284     5.6234132519035e+00, 6.4938163157621e+00,
00285     7.4989420933246e+00, 8.6596432336007e+00,
00286     1.0000000000000e+01, 1.1547819846895e+01,
00287     1.3335214321633e+01, 1.5399265260595e+01,
00288     1.7782794100389e+01, 2.0535250264571e+01,
00289     2.3713737056617e+01, 2.7384196342644e+01,
00290     3.1622776601684e+01, 3.6517412725484e+01,
00291     4.2169650342858e+01, 4.8696752516586e+01,
00292     5.6234132519035e+01, 6.4938163157621e+01,
00293     7.4989420933246e+01, 8.6596432336007e+01,
00294     1.0000000000000e+02, 1.1547819846895e+02,
00295     1.3335214321633e+02, 1.5399265260595e+02,
00296     1.7782794100389e+02, 2.0535250264571e+02,
00297     2.3713737056617e+02, 2.7384196342644e+02,
00298     3.1622776601684e+02, 3.6517412725484e+02,
00299     4.2169650342858e+02, 4.8696752516586e+02,
00300     5.6234132519035e+02, 6.4938163157621e+02,
00301     7.4989420933246e+02, 8.6596432336007e+02,
00302     1.0000000000000e+03, 1.1547819846895e+03,
00303     1.3335214321633e+03, 1.5399265260595e+03,
00304     1.7782794100389e+03, 2.0535250264571e+03,
00305     2.3713737056617e+03, 2.7384196342644e+03,
00306     3.1622776601684e+03, 3.6517412725484e+03,
00307     4.2169650342858e+03, 4.8696752516586e+03,
00308     5.6234132519035e+03, 6.4938163157621e+03,
00309     7.4989420933246e+03, 8.6596432336007e+03,
00310     1.0000000000000e+04, 1.1547819846895e+04,
00311     1.3335214321633e+04, 1.5399265260595e+04,
00312     1.7782794100389e+04, 2.0535250264571e+04,
00313     2.3713737056617e+04, 2.7384196342644e+04,
00314     3.1622776601684e+04, 3.6517412725484e+04,
00315     4.2169650342858e+04, 4.8696752516586e+04,
00316     5.6234132519035e+04, 6.4938163157621e+04,
00317     7.4989420933246e+04, 8.6596432336007e+04,
00318     1.0000000000000e+05, 1.1547819846895e+05,
00319     1.3335214321633e+05, 1.5399265260595e+05,
00320     1.7782794100389e+05, 2.0535250264571e+05,
00321     2.3713737056617e+05, 2.7384196342644e+05,
00322     3.1622776601684e+05, 3.6517412725484e+05,
00323     4.2169650342858e+05, 4.8696752516586e+05,
00324     5.6234132519035e+05, 6.4938163157621e+05,
00325     7.4989420933246e+05, 8.6596432336007e+05,
00326 };
00327 
00331 static int decode_exp_vlc(WMACodecContext *s, int ch)
00332 {
00333     int last_exp, n, code;
00334     const uint16_t *ptr;
00335     float v, max_scale;
00336     uint32_t *q, *q_end, iv;
00337     const float *ptab = pow_tab + 60;
00338     const uint32_t *iptab = (const uint32_t*)ptab;
00339 
00340     ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
00341     q = (uint32_t *)s->exponents[ch];
00342     q_end = q + s->block_len;
00343     max_scale = 0;
00344     if (s->version == 1) {
00345         last_exp = get_bits(&s->gb, 5) + 10;
00346         v = ptab[last_exp];
00347         iv = iptab[last_exp];
00348         max_scale = v;
00349         n = *ptr++;
00350         switch (n & 3) do {
00351         case 0: *q++ = iv;
00352         case 3: *q++ = iv;
00353         case 2: *q++ = iv;
00354         case 1: *q++ = iv;
00355         } while ((n -= 4) > 0);
00356     }else
00357         last_exp = 36;
00358 
00359     while (q < q_end) {
00360         code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX);
00361         if (code < 0){
00362             av_log(s->avctx, AV_LOG_ERROR, "Exponent vlc invalid\n");
00363             return -1;
00364         }
00365         /* NOTE: this offset is the same as MPEG4 AAC ! */
00366         last_exp += code - 60;
00367         if ((unsigned)last_exp + 60 >= FF_ARRAY_ELEMS(pow_tab)) {
00368             av_log(s->avctx, AV_LOG_ERROR, "Exponent out of range: %d\n",
00369                    last_exp);
00370             return -1;
00371         }
00372         v = ptab[last_exp];
00373         iv = iptab[last_exp];
00374         if (v > max_scale)
00375             max_scale = v;
00376         n = *ptr++;
00377         switch (n & 3) do {
00378         case 0: *q++ = iv;
00379         case 3: *q++ = iv;
00380         case 2: *q++ = iv;
00381         case 1: *q++ = iv;
00382         } while ((n -= 4) > 0);
00383     }
00384     s->max_exponent[ch] = max_scale;
00385     return 0;
00386 }
00387 
00388 
00395 static void wma_window(WMACodecContext *s, float *out)
00396 {
00397     float *in = s->output;
00398     int block_len, bsize, n;
00399 
00400     /* left part */
00401     if (s->block_len_bits <= s->prev_block_len_bits) {
00402         block_len = s->block_len;
00403         bsize = s->frame_len_bits - s->block_len_bits;
00404 
00405         s->dsp.vector_fmul_add(out, in, s->windows[bsize],
00406                                out, block_len);
00407 
00408     } else {
00409         block_len = 1 << s->prev_block_len_bits;
00410         n = (s->block_len - block_len) / 2;
00411         bsize = s->frame_len_bits - s->prev_block_len_bits;
00412 
00413         s->dsp.vector_fmul_add(out+n, in+n, s->windows[bsize],
00414                                out+n, block_len);
00415 
00416         memcpy(out+n+block_len, in+n+block_len, n*sizeof(float));
00417     }
00418 
00419     out += s->block_len;
00420     in += s->block_len;
00421 
00422     /* right part */
00423     if (s->block_len_bits <= s->next_block_len_bits) {
00424         block_len = s->block_len;
00425         bsize = s->frame_len_bits - s->block_len_bits;
00426 
00427         s->dsp.vector_fmul_reverse(out, in, s->windows[bsize], block_len);
00428 
00429     } else {
00430         block_len = 1 << s->next_block_len_bits;
00431         n = (s->block_len - block_len) / 2;
00432         bsize = s->frame_len_bits - s->next_block_len_bits;
00433 
00434         memcpy(out, in, n*sizeof(float));
00435 
00436         s->dsp.vector_fmul_reverse(out+n, in+n, s->windows[bsize], block_len);
00437 
00438         memset(out+n+block_len, 0, n*sizeof(float));
00439     }
00440 }
00441 
00442 
00447 static int wma_decode_block(WMACodecContext *s)
00448 {
00449     int n, v, a, ch, bsize;
00450     int coef_nb_bits, total_gain;
00451     int nb_coefs[MAX_CHANNELS];
00452     float mdct_norm;
00453     FFTContext *mdct;
00454 
00455 #ifdef TRACE
00456     tprintf(s->avctx, "***decode_block: %d:%d\n", s->frame_count - 1, s->block_num);
00457 #endif
00458 
00459     /* compute current block length */
00460     if (s->use_variable_block_len) {
00461         n = av_log2(s->nb_block_sizes - 1) + 1;
00462 
00463         if (s->reset_block_lengths) {
00464             s->reset_block_lengths = 0;
00465             v = get_bits(&s->gb, n);
00466             if (v >= s->nb_block_sizes){
00467                 av_log(s->avctx, AV_LOG_ERROR, "prev_block_len_bits %d out of range\n", s->frame_len_bits - v);
00468                 return -1;
00469             }
00470             s->prev_block_len_bits = s->frame_len_bits - v;
00471             v = get_bits(&s->gb, n);
00472             if (v >= s->nb_block_sizes){
00473                 av_log(s->avctx, AV_LOG_ERROR, "block_len_bits %d out of range\n", s->frame_len_bits - v);
00474                 return -1;
00475             }
00476             s->block_len_bits = s->frame_len_bits - v;
00477         } else {
00478             /* update block lengths */
00479             s->prev_block_len_bits = s->block_len_bits;
00480             s->block_len_bits = s->next_block_len_bits;
00481         }
00482         v = get_bits(&s->gb, n);
00483         if (v >= s->nb_block_sizes){
00484             av_log(s->avctx, AV_LOG_ERROR, "next_block_len_bits %d out of range\n", s->frame_len_bits - v);
00485             return -1;
00486         }
00487         s->next_block_len_bits = s->frame_len_bits - v;
00488     } else {
00489         /* fixed block len */
00490         s->next_block_len_bits = s->frame_len_bits;
00491         s->prev_block_len_bits = s->frame_len_bits;
00492         s->block_len_bits = s->frame_len_bits;
00493     }
00494 
00495     if (s->frame_len_bits - s->block_len_bits >= s->nb_block_sizes){
00496         av_log(s->avctx, AV_LOG_ERROR, "block_len_bits not initialized to a valid value\n");
00497         return -1;
00498     }
00499 
00500     /* now check if the block length is coherent with the frame length */
00501     s->block_len = 1 << s->block_len_bits;
00502     if ((s->block_pos + s->block_len) > s->frame_len){
00503         av_log(s->avctx, AV_LOG_ERROR, "frame_len overflow\n");
00504         return -1;
00505     }
00506 
00507     if (s->nb_channels == 2) {
00508         s->ms_stereo = get_bits1(&s->gb);
00509     }
00510     v = 0;
00511     for(ch = 0; ch < s->nb_channels; ch++) {
00512         a = get_bits1(&s->gb);
00513         s->channel_coded[ch] = a;
00514         v |= a;
00515     }
00516 
00517     bsize = s->frame_len_bits - s->block_len_bits;
00518 
00519     /* if no channel coded, no need to go further */
00520     /* XXX: fix potential framing problems */
00521     if (!v)
00522         goto next;
00523 
00524     /* read total gain and extract corresponding number of bits for
00525        coef escape coding */
00526     total_gain = 1;
00527     for(;;) {
00528         a = get_bits(&s->gb, 7);
00529         total_gain += a;
00530         if (a != 127)
00531             break;
00532     }
00533 
00534     coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
00535 
00536     /* compute number of coefficients */
00537     n = s->coefs_end[bsize] - s->coefs_start;
00538     for(ch = 0; ch < s->nb_channels; ch++)
00539         nb_coefs[ch] = n;
00540 
00541     /* complex coding */
00542     if (s->use_noise_coding) {
00543 
00544         for(ch = 0; ch < s->nb_channels; ch++) {
00545             if (s->channel_coded[ch]) {
00546                 int i, n, a;
00547                 n = s->exponent_high_sizes[bsize];
00548                 for(i=0;i<n;i++) {
00549                     a = get_bits1(&s->gb);
00550                     s->high_band_coded[ch][i] = a;
00551                     /* if noise coding, the coefficients are not transmitted */
00552                     if (a)
00553                         nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
00554                 }
00555             }
00556         }
00557         for(ch = 0; ch < s->nb_channels; ch++) {
00558             if (s->channel_coded[ch]) {
00559                 int i, n, val, code;
00560 
00561                 n = s->exponent_high_sizes[bsize];
00562                 val = (int)0x80000000;
00563                 for(i=0;i<n;i++) {
00564                     if (s->high_band_coded[ch][i]) {
00565                         if (val == (int)0x80000000) {
00566                             val = get_bits(&s->gb, 7) - 19;
00567                         } else {
00568                             code = get_vlc2(&s->gb, s->hgain_vlc.table, HGAINVLCBITS, HGAINMAX);
00569                             if (code < 0){
00570                                 av_log(s->avctx, AV_LOG_ERROR, "hgain vlc invalid\n");
00571                                 return -1;
00572                             }
00573                             val += code - 18;
00574                         }
00575                         s->high_band_values[ch][i] = val;
00576                     }
00577                 }
00578             }
00579         }
00580     }
00581 
00582     /* exponents can be reused in short blocks. */
00583     if ((s->block_len_bits == s->frame_len_bits) ||
00584         get_bits1(&s->gb)) {
00585         for(ch = 0; ch < s->nb_channels; ch++) {
00586             if (s->channel_coded[ch]) {
00587                 if (s->use_exp_vlc) {
00588                     if (decode_exp_vlc(s, ch) < 0)
00589                         return -1;
00590                 } else {
00591                     decode_exp_lsp(s, ch);
00592                 }
00593                 s->exponents_bsize[ch] = bsize;
00594             }
00595         }
00596     }
00597 
00598     /* parse spectral coefficients : just RLE encoding */
00599     for(ch = 0; ch < s->nb_channels; ch++) {
00600         if (s->channel_coded[ch]) {
00601             int tindex;
00602             WMACoef* ptr = &s->coefs1[ch][0];
00603 
00604             /* special VLC tables are used for ms stereo because
00605                there is potentially less energy there */
00606             tindex = (ch == 1 && s->ms_stereo);
00607             memset(ptr, 0, s->block_len * sizeof(WMACoef));
00608             ff_wma_run_level_decode(s->avctx, &s->gb, &s->coef_vlc[tindex],
00609                   s->level_table[tindex], s->run_table[tindex],
00610                   0, ptr, 0, nb_coefs[ch],
00611                   s->block_len, s->frame_len_bits, coef_nb_bits);
00612         }
00613         if (s->version == 1 && s->nb_channels >= 2) {
00614             align_get_bits(&s->gb);
00615         }
00616     }
00617 
00618     /* normalize */
00619     {
00620         int n4 = s->block_len / 2;
00621         mdct_norm = 1.0 / (float)n4;
00622         if (s->version == 1) {
00623             mdct_norm *= sqrt(n4);
00624         }
00625     }
00626 
00627     /* finally compute the MDCT coefficients */
00628     for(ch = 0; ch < s->nb_channels; ch++) {
00629         if (s->channel_coded[ch]) {
00630             WMACoef *coefs1;
00631             float *coefs, *exponents, mult, mult1, noise;
00632             int i, j, n, n1, last_high_band, esize;
00633             float exp_power[HIGH_BAND_MAX_SIZE];
00634 
00635             coefs1 = s->coefs1[ch];
00636             exponents = s->exponents[ch];
00637             esize = s->exponents_bsize[ch];
00638             mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
00639             mult *= mdct_norm;
00640             coefs = s->coefs[ch];
00641             if (s->use_noise_coding) {
00642                 mult1 = mult;
00643                 /* very low freqs : noise */
00644                 for(i = 0;i < s->coefs_start; i++) {
00645                     *coefs++ = s->noise_table[s->noise_index] *
00646                       exponents[i<<bsize>>esize] * mult1;
00647                     s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
00648                 }
00649 
00650                 n1 = s->exponent_high_sizes[bsize];
00651 
00652                 /* compute power of high bands */
00653                 exponents = s->exponents[ch] +
00654                     (s->high_band_start[bsize]<<bsize>>esize);
00655                 last_high_band = 0; /* avoid warning */
00656                 for(j=0;j<n1;j++) {
00657                     n = s->exponent_high_bands[s->frame_len_bits -
00658                                               s->block_len_bits][j];
00659                     if (s->high_band_coded[ch][j]) {
00660                         float e2, v;
00661                         e2 = 0;
00662                         for(i = 0;i < n; i++) {
00663                             v = exponents[i<<bsize>>esize];
00664                             e2 += v * v;
00665                         }
00666                         exp_power[j] = e2 / n;
00667                         last_high_band = j;
00668                         tprintf(s->avctx, "%d: power=%f (%d)\n", j, exp_power[j], n);
00669                     }
00670                     exponents += n<<bsize>>esize;
00671                 }
00672 
00673                 /* main freqs and high freqs */
00674                 exponents = s->exponents[ch] + (s->coefs_start<<bsize>>esize);
00675                 for(j=-1;j<n1;j++) {
00676                     if (j < 0) {
00677                         n = s->high_band_start[bsize] -
00678                             s->coefs_start;
00679                     } else {
00680                         n = s->exponent_high_bands[s->frame_len_bits -
00681                                                   s->block_len_bits][j];
00682                     }
00683                     if (j >= 0 && s->high_band_coded[ch][j]) {
00684                         /* use noise with specified power */
00685                         mult1 = sqrt(exp_power[j] / exp_power[last_high_band]);
00686                         /* XXX: use a table */
00687                         mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05);
00688                         mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult);
00689                         mult1 *= mdct_norm;
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++ =  noise *
00694                                 exponents[i<<bsize>>esize] * mult1;
00695                         }
00696                         exponents += n<<bsize>>esize;
00697                     } else {
00698                         /* coded values + small noise */
00699                         for(i = 0;i < n; i++) {
00700                             noise = s->noise_table[s->noise_index];
00701                             s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
00702                             *coefs++ = ((*coefs1++) + noise) *
00703                                 exponents[i<<bsize>>esize] * mult;
00704                         }
00705                         exponents += n<<bsize>>esize;
00706                     }
00707                 }
00708 
00709                 /* very high freqs : noise */
00710                 n = s->block_len - s->coefs_end[bsize];
00711                 mult1 = mult * exponents[((-1<<bsize))>>esize];
00712                 for(i = 0; i < n; i++) {
00713                     *coefs++ = s->noise_table[s->noise_index] * mult1;
00714                     s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
00715                 }
00716             } else {
00717                 /* XXX: optimize more */
00718                 for(i = 0;i < s->coefs_start; i++)
00719                     *coefs++ = 0.0;
00720                 n = nb_coefs[ch];
00721                 for(i = 0;i < n; i++) {
00722                     *coefs++ = coefs1[i] * exponents[i<<bsize>>esize] * mult;
00723                 }
00724                 n = s->block_len - s->coefs_end[bsize];
00725                 for(i = 0;i < n; i++)
00726                     *coefs++ = 0.0;
00727             }
00728         }
00729     }
00730 
00731 #ifdef TRACE
00732     for(ch = 0; ch < s->nb_channels; ch++) {
00733         if (s->channel_coded[ch]) {
00734             dump_floats(s, "exponents", 3, s->exponents[ch], s->block_len);
00735             dump_floats(s, "coefs", 1, s->coefs[ch], s->block_len);
00736         }
00737     }
00738 #endif
00739 
00740     if (s->ms_stereo && s->channel_coded[1]) {
00741         /* nominal case for ms stereo: we do it before mdct */
00742         /* no need to optimize this case because it should almost
00743            never happen */
00744         if (!s->channel_coded[0]) {
00745             tprintf(s->avctx, "rare ms-stereo case happened\n");
00746             memset(s->coefs[0], 0, sizeof(float) * s->block_len);
00747             s->channel_coded[0] = 1;
00748         }
00749 
00750         s->dsp.butterflies_float(s->coefs[0], s->coefs[1], s->block_len);
00751     }
00752 
00753 next:
00754     mdct = &s->mdct_ctx[bsize];
00755 
00756     for(ch = 0; ch < s->nb_channels; ch++) {
00757         int n4, index;
00758 
00759         n4 = s->block_len / 2;
00760         if(s->channel_coded[ch]){
00761             mdct->imdct_calc(mdct, s->output, s->coefs[ch]);
00762         }else if(!(s->ms_stereo && ch==1))
00763             memset(s->output, 0, sizeof(s->output));
00764 
00765         /* multiply by the window and add in the frame */
00766         index = (s->frame_len / 2) + s->block_pos - n4;
00767         wma_window(s, &s->frame_out[ch][index]);
00768     }
00769 
00770     /* update block number */
00771     s->block_num++;
00772     s->block_pos += s->block_len;
00773     if (s->block_pos >= s->frame_len)
00774         return 1;
00775     else
00776         return 0;
00777 }
00778 
00779 /* decode a frame of frame_len samples */
00780 static int wma_decode_frame(WMACodecContext *s, int16_t *samples)
00781 {
00782     int ret, n, ch, incr;
00783     const float *output[MAX_CHANNELS];
00784 
00785 #ifdef TRACE
00786     tprintf(s->avctx, "***decode_frame: %d size=%d\n", s->frame_count++, s->frame_len);
00787 #endif
00788 
00789     /* read each block */
00790     s->block_num = 0;
00791     s->block_pos = 0;
00792     for(;;) {
00793         ret = wma_decode_block(s);
00794         if (ret < 0)
00795             return -1;
00796         if (ret)
00797             break;
00798     }
00799 
00800     /* convert frame to integer */
00801     n = s->frame_len;
00802     incr = s->nb_channels;
00803     for (ch = 0; ch < MAX_CHANNELS; ch++)
00804         output[ch] = s->frame_out[ch];
00805     s->fmt_conv.float_to_int16_interleave(samples, output, n, incr);
00806     for (ch = 0; ch < incr; ch++) {
00807         /* prepare for next block */
00808         memmove(&s->frame_out[ch][0], &s->frame_out[ch][n], n * sizeof(float));
00809     }
00810 
00811 #ifdef TRACE
00812     dump_shorts(s, "samples", samples, n * s->nb_channels);
00813 #endif
00814     return 0;
00815 }
00816 
00817 static int wma_decode_superframe(AVCodecContext *avctx,
00818                                  void *data, int *data_size,
00819                                  AVPacket *avpkt)
00820 {
00821     const uint8_t *buf = avpkt->data;
00822     int buf_size = avpkt->size;
00823     WMACodecContext *s = avctx->priv_data;
00824     int nb_frames, bit_offset, i, pos, len;
00825     uint8_t *q;
00826     int16_t *samples;
00827 
00828     tprintf(avctx, "***decode_superframe:\n");
00829 
00830     if(buf_size==0){
00831         s->last_superframe_len = 0;
00832         return 0;
00833     }
00834     if (buf_size < s->block_align)
00835         return AVERROR(EINVAL);
00836     if(s->block_align)
00837         buf_size = s->block_align;
00838 
00839     samples = data;
00840 
00841     init_get_bits(&s->gb, buf, buf_size*8);
00842 
00843     if (s->use_bit_reservoir) {
00844         /* read super frame header */
00845         skip_bits(&s->gb, 4); /* super frame index */
00846         nb_frames = get_bits(&s->gb, 4) - 1;
00847 
00848         if((nb_frames+1) * s->nb_channels * s->frame_len * sizeof(int16_t) > *data_size){
00849             av_log(s->avctx, AV_LOG_ERROR, "Insufficient output space\n");
00850             goto fail;
00851         }
00852 
00853         bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
00854 
00855         if (s->last_superframe_len > 0) {
00856             //        printf("skip=%d\n", s->last_bitoffset);
00857             /* add bit_offset bits to last frame */
00858             if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
00859                 MAX_CODED_SUPERFRAME_SIZE)
00860                 goto fail;
00861             q = s->last_superframe + s->last_superframe_len;
00862             len = bit_offset;
00863             while (len > 7) {
00864                 *q++ = (get_bits)(&s->gb, 8);
00865                 len -= 8;
00866             }
00867             if (len > 0) {
00868                 *q++ = (get_bits)(&s->gb, len) << (8 - len);
00869             }
00870 
00871             /* XXX: bit_offset bits into last frame */
00872             init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE*8);
00873             /* skip unused bits */
00874             if (s->last_bitoffset > 0)
00875                 skip_bits(&s->gb, s->last_bitoffset);
00876             /* this frame is stored in the last superframe and in the
00877                current one */
00878             if (wma_decode_frame(s, samples) < 0)
00879                 goto fail;
00880             samples += s->nb_channels * s->frame_len;
00881         }
00882 
00883         /* read each frame starting from bit_offset */
00884         pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
00885         if (pos >= MAX_CODED_SUPERFRAME_SIZE * 8)
00886             return AVERROR_INVALIDDATA;
00887         init_get_bits(&s->gb, buf + (pos >> 3), (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3))*8);
00888         len = pos & 7;
00889         if (len > 0)
00890             skip_bits(&s->gb, len);
00891 
00892         s->reset_block_lengths = 1;
00893         for(i=0;i<nb_frames;i++) {
00894             if (wma_decode_frame(s, samples) < 0)
00895                 goto fail;
00896             samples += s->nb_channels * s->frame_len;
00897         }
00898 
00899         /* we copy the end of the frame in the last frame buffer */
00900         pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
00901         s->last_bitoffset = pos & 7;
00902         pos >>= 3;
00903         len = buf_size - pos;
00904         if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
00905             av_log(s->avctx, AV_LOG_ERROR, "len %d invalid\n", len);
00906             goto fail;
00907         }
00908         s->last_superframe_len = len;
00909         memcpy(s->last_superframe, buf + pos, len);
00910     } else {
00911         if(s->nb_channels * s->frame_len * sizeof(int16_t) > *data_size){
00912             av_log(s->avctx, AV_LOG_ERROR, "Insufficient output space\n");
00913             goto fail;
00914         }
00915         /* single frame decode */
00916         if (wma_decode_frame(s, samples) < 0)
00917             goto fail;
00918         samples += s->nb_channels * s->frame_len;
00919     }
00920 
00921 //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);
00922     *data_size = (int8_t *)samples - (int8_t *)data;
00923     return buf_size;
00924  fail:
00925     /* when error, we reset the bit reservoir */
00926     s->last_superframe_len = 0;
00927     return -1;
00928 }
00929 
00930 static av_cold void flush(AVCodecContext *avctx)
00931 {
00932     WMACodecContext *s = avctx->priv_data;
00933 
00934     s->last_bitoffset=
00935     s->last_superframe_len= 0;
00936 }
00937 
00938 AVCodec ff_wmav1_decoder =
00939 {
00940     "wmav1",
00941     AVMEDIA_TYPE_AUDIO,
00942     CODEC_ID_WMAV1,
00943     sizeof(WMACodecContext),
00944     wma_decode_init,
00945     NULL,
00946     ff_wma_end,
00947     wma_decode_superframe,
00948     .flush=flush,
00949     .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"),
00950 };
00951 
00952 AVCodec ff_wmav2_decoder =
00953 {
00954     "wmav2",
00955     AVMEDIA_TYPE_AUDIO,
00956     CODEC_ID_WMAV2,
00957     sizeof(WMACodecContext),
00958     wma_decode_init,
00959     NULL,
00960     ff_wma_end,
00961     wma_decode_superframe,
00962     .flush=flush,
00963     .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"),
00964 };