Libav 0.7.1
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00001 /* 00002 * WMA compatible encoder 00003 * Copyright (c) 2007 Michael Niedermayer 00004 * 00005 * This file is part of Libav. 00006 * 00007 * Libav 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 * Libav 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 Libav; if not, write to the Free Software 00019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00020 */ 00021 00022 #include "avcodec.h" 00023 #include "wma.h" 00024 00025 #undef NDEBUG 00026 #include <assert.h> 00027 00028 00029 static int encode_init(AVCodecContext * avctx){ 00030 WMACodecContext *s = avctx->priv_data; 00031 int i, flags1, flags2; 00032 uint8_t *extradata; 00033 00034 s->avctx = avctx; 00035 00036 if(avctx->channels > MAX_CHANNELS) { 00037 av_log(avctx, AV_LOG_ERROR, "too many channels: got %i, need %i or fewer", 00038 avctx->channels, MAX_CHANNELS); 00039 return AVERROR(EINVAL); 00040 } 00041 00042 if (avctx->sample_rate > 48000) { 00043 av_log(avctx, AV_LOG_ERROR, "sample rate is too high: %d > 48kHz", 00044 avctx->sample_rate); 00045 return AVERROR(EINVAL); 00046 } 00047 00048 if(avctx->bit_rate < 24*1000) { 00049 av_log(avctx, AV_LOG_ERROR, "bitrate too low: got %i, need 24000 or higher\n", 00050 avctx->bit_rate); 00051 return AVERROR(EINVAL); 00052 } 00053 00054 /* extract flag infos */ 00055 flags1 = 0; 00056 flags2 = 1; 00057 if (avctx->codec->id == CODEC_ID_WMAV1) { 00058 extradata= av_malloc(4); 00059 avctx->extradata_size= 4; 00060 AV_WL16(extradata, flags1); 00061 AV_WL16(extradata+2, flags2); 00062 } else if (avctx->codec->id == CODEC_ID_WMAV2) { 00063 extradata= av_mallocz(10); 00064 avctx->extradata_size= 10; 00065 AV_WL32(extradata, flags1); 00066 AV_WL16(extradata+4, flags2); 00067 }else 00068 assert(0); 00069 avctx->extradata= extradata; 00070 s->use_exp_vlc = flags2 & 0x0001; 00071 s->use_bit_reservoir = flags2 & 0x0002; 00072 s->use_variable_block_len = flags2 & 0x0004; 00073 if (avctx->channels == 2) 00074 s->ms_stereo = 1; 00075 00076 ff_wma_init(avctx, flags2); 00077 00078 /* init MDCT */ 00079 for(i = 0; i < s->nb_block_sizes; i++) 00080 ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 0, 1.0); 00081 00082 s->block_align = avctx->bit_rate * (int64_t)s->frame_len / 00083 (avctx->sample_rate * 8); 00084 s->block_align = FFMIN(s->block_align, MAX_CODED_SUPERFRAME_SIZE); 00085 avctx->block_align = s->block_align; 00086 avctx->bit_rate = avctx->block_align * 8LL * avctx->sample_rate / 00087 s->frame_len; 00088 //av_log(NULL, AV_LOG_ERROR, "%d %d %d %d\n", s->block_align, avctx->bit_rate, s->frame_len, avctx->sample_rate); 00089 avctx->frame_size= s->frame_len; 00090 00091 return 0; 00092 } 00093 00094 00095 static void apply_window_and_mdct(AVCodecContext * avctx, const signed short * audio, int len) { 00096 WMACodecContext *s = avctx->priv_data; 00097 int window_index= s->frame_len_bits - s->block_len_bits; 00098 FFTContext *mdct = &s->mdct_ctx[window_index]; 00099 int i, j, channel; 00100 const float * win = s->windows[window_index]; 00101 int window_len = 1 << s->block_len_bits; 00102 float n = window_len/2; 00103 00104 for (channel = 0; channel < avctx->channels; channel++) { 00105 memcpy(s->output, s->frame_out[channel], sizeof(float)*window_len); 00106 j = channel; 00107 for (i = 0; i < len; i++, j += avctx->channels){ 00108 s->output[i+window_len] = audio[j] / n * win[window_len - i - 1]; 00109 s->frame_out[channel][i] = audio[j] / n * win[i]; 00110 } 00111 mdct->mdct_calc(mdct, s->coefs[channel], s->output); 00112 } 00113 } 00114 00115 //FIXME use for decoding too 00116 static void init_exp(WMACodecContext *s, int ch, const int *exp_param){ 00117 int n; 00118 const uint16_t *ptr; 00119 float v, *q, max_scale, *q_end; 00120 00121 ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits]; 00122 q = s->exponents[ch]; 00123 q_end = q + s->block_len; 00124 max_scale = 0; 00125 while (q < q_end) { 00126 /* XXX: use a table */ 00127 v = pow(10, *exp_param++ * (1.0 / 16.0)); 00128 max_scale= FFMAX(max_scale, v); 00129 n = *ptr++; 00130 do { 00131 *q++ = v; 00132 } while (--n); 00133 } 00134 s->max_exponent[ch] = max_scale; 00135 } 00136 00137 static void encode_exp_vlc(WMACodecContext *s, int ch, const int *exp_param){ 00138 int last_exp; 00139 const uint16_t *ptr; 00140 float *q, *q_end; 00141 00142 ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits]; 00143 q = s->exponents[ch]; 00144 q_end = q + s->block_len; 00145 if (s->version == 1) { 00146 last_exp= *exp_param++; 00147 assert(last_exp-10 >= 0 && last_exp-10 < 32); 00148 put_bits(&s->pb, 5, last_exp - 10); 00149 q+= *ptr++; 00150 }else 00151 last_exp = 36; 00152 while (q < q_end) { 00153 int exp = *exp_param++; 00154 int code = exp - last_exp + 60; 00155 assert(code >= 0 && code < 120); 00156 put_bits(&s->pb, ff_aac_scalefactor_bits[code], ff_aac_scalefactor_code[code]); 00157 /* XXX: use a table */ 00158 q+= *ptr++; 00159 last_exp= exp; 00160 } 00161 } 00162 00163 static int encode_block(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], int total_gain){ 00164 int v, bsize, ch, coef_nb_bits, parse_exponents; 00165 float mdct_norm; 00166 int nb_coefs[MAX_CHANNELS]; 00167 static const int fixed_exp[25]={20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20}; 00168 00169 //FIXME remove duplication relative to decoder 00170 if (s->use_variable_block_len) { 00171 assert(0); //FIXME not implemented 00172 }else{ 00173 /* fixed block len */ 00174 s->next_block_len_bits = s->frame_len_bits; 00175 s->prev_block_len_bits = s->frame_len_bits; 00176 s->block_len_bits = s->frame_len_bits; 00177 } 00178 00179 s->block_len = 1 << s->block_len_bits; 00180 // assert((s->block_pos + s->block_len) <= s->frame_len); 00181 bsize = s->frame_len_bits - s->block_len_bits; 00182 00183 //FIXME factor 00184 v = s->coefs_end[bsize] - s->coefs_start; 00185 for(ch = 0; ch < s->nb_channels; ch++) 00186 nb_coefs[ch] = v; 00187 { 00188 int n4 = s->block_len / 2; 00189 mdct_norm = 1.0 / (float)n4; 00190 if (s->version == 1) { 00191 mdct_norm *= sqrt(n4); 00192 } 00193 } 00194 00195 if (s->nb_channels == 2) { 00196 put_bits(&s->pb, 1, !!s->ms_stereo); 00197 } 00198 00199 for(ch = 0; ch < s->nb_channels; ch++) { 00200 s->channel_coded[ch] = 1; //FIXME only set channel_coded when needed, instead of always 00201 if (s->channel_coded[ch]) { 00202 init_exp(s, ch, fixed_exp); 00203 } 00204 } 00205 00206 for(ch = 0; ch < s->nb_channels; ch++) { 00207 if (s->channel_coded[ch]) { 00208 WMACoef *coefs1; 00209 float *coefs, *exponents, mult; 00210 int i, n; 00211 00212 coefs1 = s->coefs1[ch]; 00213 exponents = s->exponents[ch]; 00214 mult = pow(10, total_gain * 0.05) / s->max_exponent[ch]; 00215 mult *= mdct_norm; 00216 coefs = src_coefs[ch]; 00217 if (s->use_noise_coding && 0) { 00218 assert(0); //FIXME not implemented 00219 } else { 00220 coefs += s->coefs_start; 00221 n = nb_coefs[ch]; 00222 for(i = 0;i < n; i++){ 00223 double t= *coefs++ / (exponents[i] * mult); 00224 if(t<-32768 || t>32767) 00225 return -1; 00226 00227 coefs1[i] = lrint(t); 00228 } 00229 } 00230 } 00231 } 00232 00233 v = 0; 00234 for(ch = 0; ch < s->nb_channels; ch++) { 00235 int a = s->channel_coded[ch]; 00236 put_bits(&s->pb, 1, a); 00237 v |= a; 00238 } 00239 00240 if (!v) 00241 return 1; 00242 00243 for(v= total_gain-1; v>=127; v-= 127) 00244 put_bits(&s->pb, 7, 127); 00245 put_bits(&s->pb, 7, v); 00246 00247 coef_nb_bits= ff_wma_total_gain_to_bits(total_gain); 00248 00249 if (s->use_noise_coding) { 00250 for(ch = 0; ch < s->nb_channels; ch++) { 00251 if (s->channel_coded[ch]) { 00252 int i, n; 00253 n = s->exponent_high_sizes[bsize]; 00254 for(i=0;i<n;i++) { 00255 put_bits(&s->pb, 1, s->high_band_coded[ch][i]= 0); 00256 if (0) 00257 nb_coefs[ch] -= s->exponent_high_bands[bsize][i]; 00258 } 00259 } 00260 } 00261 } 00262 00263 parse_exponents = 1; 00264 if (s->block_len_bits != s->frame_len_bits) { 00265 put_bits(&s->pb, 1, parse_exponents); 00266 } 00267 00268 if (parse_exponents) { 00269 for(ch = 0; ch < s->nb_channels; ch++) { 00270 if (s->channel_coded[ch]) { 00271 if (s->use_exp_vlc) { 00272 encode_exp_vlc(s, ch, fixed_exp); 00273 } else { 00274 assert(0); //FIXME not implemented 00275 // encode_exp_lsp(s, ch); 00276 } 00277 } 00278 } 00279 } else { 00280 assert(0); //FIXME not implemented 00281 } 00282 00283 for(ch = 0; ch < s->nb_channels; ch++) { 00284 if (s->channel_coded[ch]) { 00285 int run, tindex; 00286 WMACoef *ptr, *eptr; 00287 tindex = (ch == 1 && s->ms_stereo); 00288 ptr = &s->coefs1[ch][0]; 00289 eptr = ptr + nb_coefs[ch]; 00290 00291 run=0; 00292 for(;ptr < eptr; ptr++){ 00293 if(*ptr){ 00294 int level= *ptr; 00295 int abs_level= FFABS(level); 00296 int code= 0; 00297 if(abs_level <= s->coef_vlcs[tindex]->max_level){ 00298 if(run < s->coef_vlcs[tindex]->levels[abs_level-1]) 00299 code= run + s->int_table[tindex][abs_level-1]; 00300 } 00301 00302 assert(code < s->coef_vlcs[tindex]->n); 00303 put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[code], s->coef_vlcs[tindex]->huffcodes[code]); 00304 00305 if(code == 0){ 00306 if(1<<coef_nb_bits <= abs_level) 00307 return -1; 00308 00309 00310 //Workaround minor rounding differences for the regression tests, FIXME we should find and replace the problematic float by fixpoint for reg tests 00311 if(abs_level == 0x71B && (s->avctx->flags & CODEC_FLAG_BITEXACT)) abs_level=0x71A; 00312 00313 put_bits(&s->pb, coef_nb_bits, abs_level); 00314 put_bits(&s->pb, s->frame_len_bits, run); 00315 } 00316 put_bits(&s->pb, 1, level < 0); //FIXME the sign is fliped somewhere 00317 run=0; 00318 }else{ 00319 run++; 00320 } 00321 } 00322 if(run) 00323 put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[1], s->coef_vlcs[tindex]->huffcodes[1]); 00324 } 00325 if (s->version == 1 && s->nb_channels >= 2) { 00326 align_put_bits(&s->pb); 00327 } 00328 } 00329 return 0; 00330 } 00331 00332 static int encode_frame(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], uint8_t *buf, int buf_size, int total_gain){ 00333 init_put_bits(&s->pb, buf, buf_size); 00334 00335 if (s->use_bit_reservoir) { 00336 assert(0);//FIXME not implemented 00337 }else{ 00338 if(encode_block(s, src_coefs, total_gain) < 0) 00339 return INT_MAX; 00340 } 00341 00342 align_put_bits(&s->pb); 00343 00344 return put_bits_count(&s->pb)/8 - s->block_align; 00345 } 00346 00347 static int encode_superframe(AVCodecContext *avctx, 00348 unsigned char *buf, int buf_size, void *data){ 00349 WMACodecContext *s = avctx->priv_data; 00350 const short *samples = data; 00351 int i, total_gain; 00352 00353 s->block_len_bits= s->frame_len_bits; //required by non variable block len 00354 s->block_len = 1 << s->block_len_bits; 00355 00356 apply_window_and_mdct(avctx, samples, avctx->frame_size); 00357 00358 if (s->ms_stereo) { 00359 float a, b; 00360 int i; 00361 00362 for(i = 0; i < s->block_len; i++) { 00363 a = s->coefs[0][i]*0.5; 00364 b = s->coefs[1][i]*0.5; 00365 s->coefs[0][i] = a + b; 00366 s->coefs[1][i] = a - b; 00367 } 00368 } 00369 00370 if (buf_size < 2 * MAX_CODED_SUPERFRAME_SIZE) { 00371 av_log(avctx, AV_LOG_ERROR, "output buffer size is too small\n"); 00372 return AVERROR(EINVAL); 00373 } 00374 00375 #if 1 00376 total_gain= 128; 00377 for(i=64; i; i>>=1){ 00378 int error= encode_frame(s, s->coefs, buf, buf_size, total_gain-i); 00379 if(error<0) 00380 total_gain-= i; 00381 } 00382 #else 00383 total_gain= 90; 00384 best= encode_frame(s, s->coefs, buf, buf_size, total_gain); 00385 for(i=32; i; i>>=1){ 00386 int scoreL= encode_frame(s, s->coefs, buf, buf_size, total_gain-i); 00387 int scoreR= encode_frame(s, s->coefs, buf, buf_size, total_gain+i); 00388 av_log(NULL, AV_LOG_ERROR, "%d %d %d (%d)\n", scoreL, best, scoreR, total_gain); 00389 if(scoreL < FFMIN(best, scoreR)){ 00390 best = scoreL; 00391 total_gain -= i; 00392 }else if(scoreR < best){ 00393 best = scoreR; 00394 total_gain += i; 00395 } 00396 } 00397 #endif 00398 00399 encode_frame(s, s->coefs, buf, buf_size, total_gain); 00400 assert((put_bits_count(&s->pb) & 7) == 0); 00401 i= s->block_align - (put_bits_count(&s->pb)+7)/8; 00402 assert(i>=0); 00403 while(i--) 00404 put_bits(&s->pb, 8, 'N'); 00405 00406 flush_put_bits(&s->pb); 00407 return put_bits_ptr(&s->pb) - s->pb.buf; 00408 } 00409 00410 AVCodec ff_wmav1_encoder = 00411 { 00412 "wmav1", 00413 AVMEDIA_TYPE_AUDIO, 00414 CODEC_ID_WMAV1, 00415 sizeof(WMACodecContext), 00416 encode_init, 00417 encode_superframe, 00418 ff_wma_end, 00419 .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE}, 00420 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"), 00421 }; 00422 00423 AVCodec ff_wmav2_encoder = 00424 { 00425 "wmav2", 00426 AVMEDIA_TYPE_AUDIO, 00427 CODEC_ID_WMAV2, 00428 sizeof(WMACodecContext), 00429 encode_init, 00430 encode_superframe, 00431 ff_wma_end, 00432 .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE}, 00433 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"), 00434 };