00001
00002
00003
00004
00005
00006
00007
00008
00009
00010
00011
00012
00013
00014
00015
00016
00017
00018
00019
00020
00021
00022 #include "avcodec.h"
00023 #include "wma.h"
00024 #include "wmadata.h"
00025
00026 #undef NDEBUG
00027 #include <assert.h>
00028
00029
00030
00031 static void init_coef_vlc(VLC *vlc,
00032 uint16_t **prun_table, uint16_t **plevel_table, uint16_t **pint_table,
00033 const CoefVLCTable *vlc_table)
00034 {
00035 int n = vlc_table->n;
00036 const uint8_t *table_bits = vlc_table->huffbits;
00037 const uint32_t *table_codes = vlc_table->huffcodes;
00038 const uint16_t *levels_table = vlc_table->levels;
00039 uint16_t *run_table, *level_table, *int_table;
00040 int i, l, j, k, level;
00041
00042 init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
00043
00044 run_table = av_malloc(n * sizeof(uint16_t));
00045 level_table = av_malloc(n * sizeof(uint16_t));
00046 int_table = av_malloc(n * sizeof(uint16_t));
00047 i = 2;
00048 level = 1;
00049 k = 0;
00050 while (i < n) {
00051 int_table[k]= i;
00052 l = levels_table[k++];
00053 for(j=0;j<l;j++) {
00054 run_table[i] = j;
00055 level_table[i] = level;
00056 i++;
00057 }
00058 level++;
00059 }
00060 *prun_table = run_table;
00061 *plevel_table = level_table;
00062 *pint_table= int_table;
00063 }
00064
00065 int ff_wma_init(AVCodecContext * avctx, int flags2)
00066 {
00067 WMACodecContext *s = avctx->priv_data;
00068 int i;
00069 float *window;
00070 float bps1, high_freq;
00071 volatile float bps;
00072 int sample_rate1;
00073 int coef_vlc_table;
00074
00075 if( avctx->sample_rate<=0 || avctx->sample_rate>50000
00076 || avctx->channels<=0 || avctx->channels>8
00077 || avctx->bit_rate<=0)
00078 return -1;
00079
00080 s->sample_rate = avctx->sample_rate;
00081 s->nb_channels = avctx->channels;
00082 s->bit_rate = avctx->bit_rate;
00083 s->block_align = avctx->block_align;
00084
00085 dsputil_init(&s->dsp, avctx);
00086
00087 if (avctx->codec->id == CODEC_ID_WMAV1) {
00088 s->version = 1;
00089 } else {
00090 s->version = 2;
00091 }
00092
00093
00094 if (s->sample_rate <= 16000) {
00095 s->frame_len_bits = 9;
00096 } else if (s->sample_rate <= 22050 ||
00097 (s->sample_rate <= 32000 && s->version == 1)) {
00098 s->frame_len_bits = 10;
00099 } else {
00100 s->frame_len_bits = 11;
00101 }
00102 s->frame_len = 1 << s->frame_len_bits;
00103 if (s->use_variable_block_len) {
00104 int nb_max, nb;
00105 nb = ((flags2 >> 3) & 3) + 1;
00106 if ((s->bit_rate / s->nb_channels) >= 32000)
00107 nb += 2;
00108 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
00109 if (nb > nb_max)
00110 nb = nb_max;
00111 s->nb_block_sizes = nb + 1;
00112 } else {
00113 s->nb_block_sizes = 1;
00114 }
00115
00116
00117 s->use_noise_coding = 1;
00118 high_freq = s->sample_rate * 0.5;
00119
00120
00121 sample_rate1 = s->sample_rate;
00122 if (s->version == 2) {
00123 if (sample_rate1 >= 44100)
00124 sample_rate1 = 44100;
00125 else if (sample_rate1 >= 22050)
00126 sample_rate1 = 22050;
00127 else if (sample_rate1 >= 16000)
00128 sample_rate1 = 16000;
00129 else if (sample_rate1 >= 11025)
00130 sample_rate1 = 11025;
00131 else if (sample_rate1 >= 8000)
00132 sample_rate1 = 8000;
00133 }
00134
00135 bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate);
00136 s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0 + 0.5)) + 2;
00137
00138
00139
00140 bps1 = bps;
00141 if (s->nb_channels == 2)
00142 bps1 = bps * 1.6;
00143 if (sample_rate1 == 44100) {
00144 if (bps1 >= 0.61)
00145 s->use_noise_coding = 0;
00146 else
00147 high_freq = high_freq * 0.4;
00148 } else if (sample_rate1 == 22050) {
00149 if (bps1 >= 1.16)
00150 s->use_noise_coding = 0;
00151 else if (bps1 >= 0.72)
00152 high_freq = high_freq * 0.7;
00153 else
00154 high_freq = high_freq * 0.6;
00155 } else if (sample_rate1 == 16000) {
00156 if (bps > 0.5)
00157 high_freq = high_freq * 0.5;
00158 else
00159 high_freq = high_freq * 0.3;
00160 } else if (sample_rate1 == 11025) {
00161 high_freq = high_freq * 0.7;
00162 } else if (sample_rate1 == 8000) {
00163 if (bps <= 0.625) {
00164 high_freq = high_freq * 0.5;
00165 } else if (bps > 0.75) {
00166 s->use_noise_coding = 0;
00167 } else {
00168 high_freq = high_freq * 0.65;
00169 }
00170 } else {
00171 if (bps >= 0.8) {
00172 high_freq = high_freq * 0.75;
00173 } else if (bps >= 0.6) {
00174 high_freq = high_freq * 0.6;
00175 } else {
00176 high_freq = high_freq * 0.5;
00177 }
00178 }
00179 dprintf(s->avctx, "flags2=0x%x\n", flags2);
00180 dprintf(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
00181 s->version, s->nb_channels, s->sample_rate, s->bit_rate,
00182 s->block_align);
00183 dprintf(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
00184 bps, bps1, high_freq, s->byte_offset_bits);
00185 dprintf(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
00186 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
00187
00188
00189 {
00190 int a, b, pos, lpos, k, block_len, i, j, n;
00191 const uint8_t *table;
00192
00193 if (s->version == 1) {
00194 s->coefs_start = 3;
00195 } else {
00196 s->coefs_start = 0;
00197 }
00198 for(k = 0; k < s->nb_block_sizes; k++) {
00199 block_len = s->frame_len >> k;
00200
00201 if (s->version == 1) {
00202 lpos = 0;
00203 for(i=0;i<25;i++) {
00204 a = wma_critical_freqs[i];
00205 b = s->sample_rate;
00206 pos = ((block_len * 2 * a) + (b >> 1)) / b;
00207 if (pos > block_len)
00208 pos = block_len;
00209 s->exponent_bands[0][i] = pos - lpos;
00210 if (pos >= block_len) {
00211 i++;
00212 break;
00213 }
00214 lpos = pos;
00215 }
00216 s->exponent_sizes[0] = i;
00217 } else {
00218
00219 table = NULL;
00220 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
00221 if (a < 3) {
00222 if (s->sample_rate >= 44100)
00223 table = exponent_band_44100[a];
00224 else if (s->sample_rate >= 32000)
00225 table = exponent_band_32000[a];
00226 else if (s->sample_rate >= 22050)
00227 table = exponent_band_22050[a];
00228 }
00229 if (table) {
00230 n = *table++;
00231 for(i=0;i<n;i++)
00232 s->exponent_bands[k][i] = table[i];
00233 s->exponent_sizes[k] = n;
00234 } else {
00235 j = 0;
00236 lpos = 0;
00237 for(i=0;i<25;i++) {
00238 a = wma_critical_freqs[i];
00239 b = s->sample_rate;
00240 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
00241 pos <<= 2;
00242 if (pos > block_len)
00243 pos = block_len;
00244 if (pos > lpos)
00245 s->exponent_bands[k][j++] = pos - lpos;
00246 if (pos >= block_len)
00247 break;
00248 lpos = pos;
00249 }
00250 s->exponent_sizes[k] = j;
00251 }
00252 }
00253
00254
00255 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
00256
00257 s->high_band_start[k] = (int)((block_len * 2 * high_freq) /
00258 s->sample_rate + 0.5);
00259 n = s->exponent_sizes[k];
00260 j = 0;
00261 pos = 0;
00262 for(i=0;i<n;i++) {
00263 int start, end;
00264 start = pos;
00265 pos += s->exponent_bands[k][i];
00266 end = pos;
00267 if (start < s->high_band_start[k])
00268 start = s->high_band_start[k];
00269 if (end > s->coefs_end[k])
00270 end = s->coefs_end[k];
00271 if (end > start)
00272 s->exponent_high_bands[k][j++] = end - start;
00273 }
00274 s->exponent_high_sizes[k] = j;
00275 #if 0
00276 tprintf(s->avctx, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
00277 s->frame_len >> k,
00278 s->coefs_end[k],
00279 s->high_band_start[k],
00280 s->exponent_high_sizes[k]);
00281 for(j=0;j<s->exponent_high_sizes[k];j++)
00282 tprintf(s->avctx, " %d", s->exponent_high_bands[k][j]);
00283 tprintf(s->avctx, "\n");
00284 #endif
00285 }
00286 }
00287
00288 #ifdef TRACE
00289 {
00290 int i, j;
00291 for(i = 0; i < s->nb_block_sizes; i++) {
00292 tprintf(s->avctx, "%5d: n=%2d:",
00293 s->frame_len >> i,
00294 s->exponent_sizes[i]);
00295 for(j=0;j<s->exponent_sizes[i];j++)
00296 tprintf(s->avctx, " %d", s->exponent_bands[i][j]);
00297 tprintf(s->avctx, "\n");
00298 }
00299 }
00300 #endif
00301
00302
00303 for(i = 0; i < s->nb_block_sizes; i++) {
00304 int n, j;
00305 float alpha;
00306 n = 1 << (s->frame_len_bits - i);
00307 window = av_malloc(sizeof(float) * n);
00308 alpha = M_PI / (2.0 * n);
00309 for(j=0;j<n;j++) {
00310 window[j] = sin((j + 0.5) * alpha);
00311 }
00312 s->windows[i] = window;
00313 }
00314
00315 s->reset_block_lengths = 1;
00316
00317 if (s->use_noise_coding) {
00318
00319
00320 if (s->use_exp_vlc)
00321 s->noise_mult = 0.02;
00322 else
00323 s->noise_mult = 0.04;
00324
00325 #ifdef TRACE
00326 for(i=0;i<NOISE_TAB_SIZE;i++)
00327 s->noise_table[i] = 1.0 * s->noise_mult;
00328 #else
00329 {
00330 unsigned int seed;
00331 float norm;
00332 seed = 1;
00333 norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult;
00334 for(i=0;i<NOISE_TAB_SIZE;i++) {
00335 seed = seed * 314159 + 1;
00336 s->noise_table[i] = (float)((int)seed) * norm;
00337 }
00338 }
00339 #endif
00340 }
00341
00342
00343 coef_vlc_table = 2;
00344 if (s->sample_rate >= 32000) {
00345 if (bps1 < 0.72)
00346 coef_vlc_table = 0;
00347 else if (bps1 < 1.16)
00348 coef_vlc_table = 1;
00349 }
00350 s->coef_vlcs[0]= &coef_vlcs[coef_vlc_table * 2 ];
00351 s->coef_vlcs[1]= &coef_vlcs[coef_vlc_table * 2 + 1];
00352 init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &s->int_table[0],
00353 s->coef_vlcs[0]);
00354 init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &s->int_table[1],
00355 s->coef_vlcs[1]);
00356
00357 return 0;
00358 }
00359
00360 int ff_wma_total_gain_to_bits(int total_gain){
00361 if (total_gain < 15) return 13;
00362 else if (total_gain < 32) return 12;
00363 else if (total_gain < 40) return 11;
00364 else if (total_gain < 45) return 10;
00365 else return 9;
00366 }
00367
00368 int ff_wma_end(AVCodecContext *avctx)
00369 {
00370 WMACodecContext *s = avctx->priv_data;
00371 int i;
00372
00373 for(i = 0; i < s->nb_block_sizes; i++)
00374 ff_mdct_end(&s->mdct_ctx[i]);
00375 for(i = 0; i < s->nb_block_sizes; i++)
00376 av_free(s->windows[i]);
00377
00378 if (s->use_exp_vlc) {
00379 free_vlc(&s->exp_vlc);
00380 }
00381 if (s->use_noise_coding) {
00382 free_vlc(&s->hgain_vlc);
00383 }
00384 for(i = 0;i < 2; i++) {
00385 free_vlc(&s->coef_vlc[i]);
00386 av_free(s->run_table[i]);
00387 av_free(s->level_table[i]);
00388 av_free(s->int_table[i]);
00389 }
00390
00391 return 0;
00392 }