1/* 2 * DSP Group TrueSpeech compatible decoder 3 * Copyright (c) 2005 Konstantin Shishkov 4 * 5 * This file is part of Libav. 6 * 7 * Libav is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * Libav is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with Libav; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include "libavutil/intreadwrite.h" 23#include "avcodec.h" 24#include "dsputil.h" 25#include "get_bits.h" 26 27#include "truespeech_data.h" 28/** 29 * @file 30 * TrueSpeech decoder. 31 */ 32 33/** 34 * TrueSpeech decoder context 35 */ 36typedef struct { 37 AVFrame frame; 38 DSPContext dsp; 39 /* input data */ 40 uint8_t buffer[32]; 41 int16_t vector[8]; ///< input vector: 5/5/4/4/4/3/3/3 42 int offset1[2]; ///< 8-bit value, used in one copying offset 43 int offset2[4]; ///< 7-bit value, encodes offsets for copying and for two-point filter 44 int pulseoff[4]; ///< 4-bit offset of pulse values block 45 int pulsepos[4]; ///< 27-bit variable, encodes 7 pulse positions 46 int pulseval[4]; ///< 7x2-bit pulse values 47 int flag; ///< 1-bit flag, shows how to choose filters 48 /* temporary data */ 49 int filtbuf[146]; // some big vector used for storing filters 50 int prevfilt[8]; // filter from previous frame 51 int16_t tmp1[8]; // coefficients for adding to out 52 int16_t tmp2[8]; // coefficients for adding to out 53 int16_t tmp3[8]; // coefficients for adding to out 54 int16_t cvector[8]; // correlated input vector 55 int filtval; // gain value for one function 56 int16_t newvec[60]; // tmp vector 57 int16_t filters[32]; // filters for every subframe 58} TSContext; 59 60static av_cold int truespeech_decode_init(AVCodecContext * avctx) 61{ 62 TSContext *c = avctx->priv_data; 63 64 if (avctx->channels != 1) { 65 av_log_ask_for_sample(avctx, "Unsupported channel count: %d\n", avctx->channels); 66 return AVERROR(EINVAL); 67 } 68 69 avctx->sample_fmt = AV_SAMPLE_FMT_S16; 70 71 dsputil_init(&c->dsp, avctx); 72 73 avcodec_get_frame_defaults(&c->frame); 74 avctx->coded_frame = &c->frame; 75 76 return 0; 77} 78 79static void truespeech_read_frame(TSContext *dec, const uint8_t *input) 80{ 81 GetBitContext gb; 82 83 dec->dsp.bswap_buf((uint32_t *)dec->buffer, (const uint32_t *)input, 8); 84 init_get_bits(&gb, dec->buffer, 32 * 8); 85 86 dec->vector[7] = ts_codebook[7][get_bits(&gb, 3)]; 87 dec->vector[6] = ts_codebook[6][get_bits(&gb, 3)]; 88 dec->vector[5] = ts_codebook[5][get_bits(&gb, 3)]; 89 dec->vector[4] = ts_codebook[4][get_bits(&gb, 4)]; 90 dec->vector[3] = ts_codebook[3][get_bits(&gb, 4)]; 91 dec->vector[2] = ts_codebook[2][get_bits(&gb, 4)]; 92 dec->vector[1] = ts_codebook[1][get_bits(&gb, 5)]; 93 dec->vector[0] = ts_codebook[0][get_bits(&gb, 5)]; 94 dec->flag = get_bits1(&gb); 95 96 dec->offset1[0] = get_bits(&gb, 4) << 4; 97 dec->offset2[3] = get_bits(&gb, 7); 98 dec->offset2[2] = get_bits(&gb, 7); 99 dec->offset2[1] = get_bits(&gb, 7); 100 dec->offset2[0] = get_bits(&gb, 7); 101 102 dec->offset1[1] = get_bits(&gb, 4); 103 dec->pulseval[1] = get_bits(&gb, 14); 104 dec->pulseval[0] = get_bits(&gb, 14); 105 106 dec->offset1[1] |= get_bits(&gb, 4) << 4; 107 dec->pulseval[3] = get_bits(&gb, 14); 108 dec->pulseval[2] = get_bits(&gb, 14); 109 110 dec->offset1[0] |= get_bits1(&gb); 111 dec->pulsepos[0] = get_bits_long(&gb, 27); 112 dec->pulseoff[0] = get_bits(&gb, 4); 113 114 dec->offset1[0] |= get_bits1(&gb) << 1; 115 dec->pulsepos[1] = get_bits_long(&gb, 27); 116 dec->pulseoff[1] = get_bits(&gb, 4); 117 118 dec->offset1[0] |= get_bits1(&gb) << 2; 119 dec->pulsepos[2] = get_bits_long(&gb, 27); 120 dec->pulseoff[2] = get_bits(&gb, 4); 121 122 dec->offset1[0] |= get_bits1(&gb) << 3; 123 dec->pulsepos[3] = get_bits_long(&gb, 27); 124 dec->pulseoff[3] = get_bits(&gb, 4); 125} 126 127static void truespeech_correlate_filter(TSContext *dec) 128{ 129 int16_t tmp[8]; 130 int i, j; 131 132 for(i = 0; i < 8; i++){ 133 if(i > 0){ 134 memcpy(tmp, dec->cvector, i * sizeof(*tmp)); 135 for(j = 0; j < i; j++) 136 dec->cvector[j] = ((tmp[i - j - 1] * dec->vector[i]) + 137 (dec->cvector[j] << 15) + 0x4000) >> 15; 138 } 139 dec->cvector[i] = (8 - dec->vector[i]) >> 3; 140 } 141 for(i = 0; i < 8; i++) 142 dec->cvector[i] = (dec->cvector[i] * ts_decay_994_1000[i]) >> 15; 143 144 dec->filtval = dec->vector[0]; 145} 146 147static void truespeech_filters_merge(TSContext *dec) 148{ 149 int i; 150 151 if(!dec->flag){ 152 for(i = 0; i < 8; i++){ 153 dec->filters[i + 0] = dec->prevfilt[i]; 154 dec->filters[i + 8] = dec->prevfilt[i]; 155 } 156 }else{ 157 for(i = 0; i < 8; i++){ 158 dec->filters[i + 0]=(dec->cvector[i] * 21846 + dec->prevfilt[i] * 10923 + 16384) >> 15; 159 dec->filters[i + 8]=(dec->cvector[i] * 10923 + dec->prevfilt[i] * 21846 + 16384) >> 15; 160 } 161 } 162 for(i = 0; i < 8; i++){ 163 dec->filters[i + 16] = dec->cvector[i]; 164 dec->filters[i + 24] = dec->cvector[i]; 165 } 166} 167 168static void truespeech_apply_twopoint_filter(TSContext *dec, int quart) 169{ 170 int16_t tmp[146 + 60], *ptr0, *ptr1; 171 const int16_t *filter; 172 int i, t, off; 173 174 t = dec->offset2[quart]; 175 if(t == 127){ 176 memset(dec->newvec, 0, 60 * sizeof(*dec->newvec)); 177 return; 178 } 179 for(i = 0; i < 146; i++) 180 tmp[i] = dec->filtbuf[i]; 181 off = (t / 25) + dec->offset1[quart >> 1] + 18; 182 off = av_clip(off, 0, 145); 183 ptr0 = tmp + 145 - off; 184 ptr1 = tmp + 146; 185 filter = (const int16_t*)ts_order2_coeffs + (t % 25) * 2; 186 for(i = 0; i < 60; i++){ 187 t = (ptr0[0] * filter[0] + ptr0[1] * filter[1] + 0x2000) >> 14; 188 ptr0++; 189 dec->newvec[i] = t; 190 ptr1[i] = t; 191 } 192} 193 194static void truespeech_place_pulses(TSContext *dec, int16_t *out, int quart) 195{ 196 int16_t tmp[7]; 197 int i, j, t; 198 const int16_t *ptr1; 199 int16_t *ptr2; 200 int coef; 201 202 memset(out, 0, 60 * sizeof(*out)); 203 for(i = 0; i < 7; i++) { 204 t = dec->pulseval[quart] & 3; 205 dec->pulseval[quart] >>= 2; 206 tmp[6 - i] = ts_pulse_scales[dec->pulseoff[quart] * 4 + t]; 207 } 208 209 coef = dec->pulsepos[quart] >> 15; 210 ptr1 = (const int16_t*)ts_pulse_values + 30; 211 ptr2 = tmp; 212 for(i = 0, j = 3; (i < 30) && (j > 0); i++){ 213 t = *ptr1++; 214 if(coef >= t) 215 coef -= t; 216 else{ 217 out[i] = *ptr2++; 218 ptr1 += 30; 219 j--; 220 } 221 } 222 coef = dec->pulsepos[quart] & 0x7FFF; 223 ptr1 = (const int16_t*)ts_pulse_values; 224 for(i = 30, j = 4; (i < 60) && (j > 0); i++){ 225 t = *ptr1++; 226 if(coef >= t) 227 coef -= t; 228 else{ 229 out[i] = *ptr2++; 230 ptr1 += 30; 231 j--; 232 } 233 } 234 235} 236 237static void truespeech_update_filters(TSContext *dec, int16_t *out, int quart) 238{ 239 int i; 240 241 memmove(dec->filtbuf, &dec->filtbuf[60], 86 * sizeof(*dec->filtbuf)); 242 for(i = 0; i < 60; i++){ 243 dec->filtbuf[i + 86] = out[i] + dec->newvec[i] - (dec->newvec[i] >> 3); 244 out[i] += dec->newvec[i]; 245 } 246} 247 248static void truespeech_synth(TSContext *dec, int16_t *out, int quart) 249{ 250 int i,k; 251 int t[8]; 252 int16_t *ptr0, *ptr1; 253 254 ptr0 = dec->tmp1; 255 ptr1 = dec->filters + quart * 8; 256 for(i = 0; i < 60; i++){ 257 int sum = 0; 258 for(k = 0; k < 8; k++) 259 sum += ptr0[k] * ptr1[k]; 260 sum = (sum + (out[i] << 12) + 0x800) >> 12; 261 out[i] = av_clip(sum, -0x7FFE, 0x7FFE); 262 for(k = 7; k > 0; k--) 263 ptr0[k] = ptr0[k - 1]; 264 ptr0[0] = out[i]; 265 } 266 267 for(i = 0; i < 8; i++) 268 t[i] = (ts_decay_35_64[i] * ptr1[i]) >> 15; 269 270 ptr0 = dec->tmp2; 271 for(i = 0; i < 60; i++){ 272 int sum = 0; 273 for(k = 0; k < 8; k++) 274 sum += ptr0[k] * t[k]; 275 for(k = 7; k > 0; k--) 276 ptr0[k] = ptr0[k - 1]; 277 ptr0[0] = out[i]; 278 out[i] = ((out[i] << 12) - sum) >> 12; 279 } 280 281 for(i = 0; i < 8; i++) 282 t[i] = (ts_decay_3_4[i] * ptr1[i]) >> 15; 283 284 ptr0 = dec->tmp3; 285 for(i = 0; i < 60; i++){ 286 int sum = out[i] << 12; 287 for(k = 0; k < 8; k++) 288 sum += ptr0[k] * t[k]; 289 for(k = 7; k > 0; k--) 290 ptr0[k] = ptr0[k - 1]; 291 ptr0[0] = av_clip((sum + 0x800) >> 12, -0x7FFE, 0x7FFE); 292 293 sum = ((ptr0[1] * (dec->filtval - (dec->filtval >> 2))) >> 4) + sum; 294 sum = sum - (sum >> 3); 295 out[i] = av_clip((sum + 0x800) >> 12, -0x7FFE, 0x7FFE); 296 } 297} 298 299static void truespeech_save_prevvec(TSContext *c) 300{ 301 int i; 302 303 for(i = 0; i < 8; i++) 304 c->prevfilt[i] = c->cvector[i]; 305} 306 307static int truespeech_decode_frame(AVCodecContext *avctx, void *data, 308 int *got_frame_ptr, AVPacket *avpkt) 309{ 310 const uint8_t *buf = avpkt->data; 311 int buf_size = avpkt->size; 312 TSContext *c = avctx->priv_data; 313 314 int i, j; 315 int16_t *samples; 316 int iterations, ret; 317 318 iterations = buf_size / 32; 319 320 if (!iterations) { 321 av_log(avctx, AV_LOG_ERROR, 322 "Too small input buffer (%d bytes), need at least 32 bytes\n", buf_size); 323 return -1; 324 } 325 326 /* get output buffer */ 327 c->frame.nb_samples = iterations * 240; 328 if ((ret = avctx->get_buffer(avctx, &c->frame)) < 0) { 329 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); 330 return ret; 331 } 332 samples = (int16_t *)c->frame.data[0]; 333 334 memset(samples, 0, iterations * 240 * sizeof(*samples)); 335 336 for(j = 0; j < iterations; j++) { 337 truespeech_read_frame(c, buf); 338 buf += 32; 339 340 truespeech_correlate_filter(c); 341 truespeech_filters_merge(c); 342 343 for(i = 0; i < 4; i++) { 344 truespeech_apply_twopoint_filter(c, i); 345 truespeech_place_pulses (c, samples, i); 346 truespeech_update_filters(c, samples, i); 347 truespeech_synth (c, samples, i); 348 samples += 60; 349 } 350 351 truespeech_save_prevvec(c); 352 } 353 354 *got_frame_ptr = 1; 355 *(AVFrame *)data = c->frame; 356 357 return buf_size; 358} 359 360AVCodec ff_truespeech_decoder = { 361 .name = "truespeech", 362 .type = AVMEDIA_TYPE_AUDIO, 363 .id = CODEC_ID_TRUESPEECH, 364 .priv_data_size = sizeof(TSContext), 365 .init = truespeech_decode_init, 366 .decode = truespeech_decode_frame, 367 .capabilities = CODEC_CAP_DR1, 368 .long_name = NULL_IF_CONFIG_SMALL("DSP Group TrueSpeech"), 369}; 370