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libavcodec/truespeech.c

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00001 /*
00002  * DSP Group TrueSpeech compatible decoder
00003  * Copyright (c) 2005 Konstantin Shishkov
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 
00022 #include "libavutil/intreadwrite.h"
00023 #include "avcodec.h"
00024 
00025 #include "truespeech_data.h"
00034 typedef struct {
00035     /* input data */
00036     int16_t vector[8];  //< input vector: 5/5/4/4/4/3/3/3
00037     int offset1[2];     //< 8-bit value, used in one copying offset
00038     int offset2[4];     //< 7-bit value, encodes offsets for copying and for two-point filter
00039     int pulseoff[4];    //< 4-bit offset of pulse values block
00040     int pulsepos[4];    //< 27-bit variable, encodes 7 pulse positions
00041     int pulseval[4];    //< 7x2-bit pulse values
00042     int flag;           //< 1-bit flag, shows how to choose filters
00043     /* temporary data */
00044     int filtbuf[146];   // some big vector used for storing filters
00045     int prevfilt[8];    // filter from previous frame
00046     int16_t tmp1[8];    // coefficients for adding to out
00047     int16_t tmp2[8];    // coefficients for adding to out
00048     int16_t tmp3[8];    // coefficients for adding to out
00049     int16_t cvector[8]; // correlated input vector
00050     int filtval;        // gain value for one function
00051     int16_t newvec[60]; // tmp vector
00052     int16_t filters[32]; // filters for every subframe
00053 } TSContext;
00054 
00055 static av_cold int truespeech_decode_init(AVCodecContext * avctx)
00056 {
00057 //    TSContext *c = avctx->priv_data;
00058 
00059     avctx->sample_fmt = SAMPLE_FMT_S16;
00060     return 0;
00061 }
00062 
00063 static void truespeech_read_frame(TSContext *dec, const uint8_t *input)
00064 {
00065     uint32_t t;
00066 
00067     /* first dword */
00068     t = AV_RL32(input);
00069     input += 4;
00070 
00071     dec->flag = t & 1;
00072 
00073     dec->vector[0] = ts_codebook[0][(t >>  1) & 0x1F];
00074     dec->vector[1] = ts_codebook[1][(t >>  6) & 0x1F];
00075     dec->vector[2] = ts_codebook[2][(t >> 11) &  0xF];
00076     dec->vector[3] = ts_codebook[3][(t >> 15) &  0xF];
00077     dec->vector[4] = ts_codebook[4][(t >> 19) &  0xF];
00078     dec->vector[5] = ts_codebook[5][(t >> 23) &  0x7];
00079     dec->vector[6] = ts_codebook[6][(t >> 26) &  0x7];
00080     dec->vector[7] = ts_codebook[7][(t >> 29) &  0x7];
00081 
00082     /* second dword */
00083     t = AV_RL32(input);
00084     input += 4;
00085 
00086     dec->offset2[0] = (t >>  0) & 0x7F;
00087     dec->offset2[1] = (t >>  7) & 0x7F;
00088     dec->offset2[2] = (t >> 14) & 0x7F;
00089     dec->offset2[3] = (t >> 21) & 0x7F;
00090 
00091     dec->offset1[0] = ((t >> 28) & 0xF) << 4;
00092 
00093     /* third dword */
00094     t = AV_RL32(input);
00095     input += 4;
00096 
00097     dec->pulseval[0] = (t >>  0) & 0x3FFF;
00098     dec->pulseval[1] = (t >> 14) & 0x3FFF;
00099 
00100     dec->offset1[1] = (t >> 28) & 0x0F;
00101 
00102     /* fourth dword */
00103     t = AV_RL32(input);
00104     input += 4;
00105 
00106     dec->pulseval[2] = (t >>  0) & 0x3FFF;
00107     dec->pulseval[3] = (t >> 14) & 0x3FFF;
00108 
00109     dec->offset1[1] |= ((t >> 28) & 0x0F) << 4;
00110 
00111     /* fifth dword */
00112     t = AV_RL32(input);
00113     input += 4;
00114 
00115     dec->pulsepos[0] = (t >> 4) & 0x7FFFFFF;
00116 
00117     dec->pulseoff[0] = (t >> 0) & 0xF;
00118 
00119     dec->offset1[0] |= (t >> 31) & 1;
00120 
00121     /* sixth dword */
00122     t = AV_RL32(input);
00123     input += 4;
00124 
00125     dec->pulsepos[1] = (t >> 4) & 0x7FFFFFF;
00126 
00127     dec->pulseoff[1] = (t >> 0) & 0xF;
00128 
00129     dec->offset1[0] |= ((t >> 31) & 1) << 1;
00130 
00131     /* seventh dword */
00132     t = AV_RL32(input);
00133     input += 4;
00134 
00135     dec->pulsepos[2] = (t >> 4) & 0x7FFFFFF;
00136 
00137     dec->pulseoff[2] = (t >> 0) & 0xF;
00138 
00139     dec->offset1[0] |= ((t >> 31) & 1) << 2;
00140 
00141     /* eighth dword */
00142     t = AV_RL32(input);
00143     input += 4;
00144 
00145     dec->pulsepos[3] = (t >> 4) & 0x7FFFFFF;
00146 
00147     dec->pulseoff[3] = (t >> 0) & 0xF;
00148 
00149     dec->offset1[0] |= ((t >> 31) & 1) << 3;
00150 
00151 }
00152 
00153 static void truespeech_correlate_filter(TSContext *dec)
00154 {
00155     int16_t tmp[8];
00156     int i, j;
00157 
00158     for(i = 0; i < 8; i++){
00159         if(i > 0){
00160             memcpy(tmp, dec->cvector, i * 2);
00161             for(j = 0; j < i; j++)
00162                 dec->cvector[j] = ((tmp[i - j - 1] * dec->vector[i]) +
00163                                    (dec->cvector[j] << 15) + 0x4000) >> 15;
00164         }
00165         dec->cvector[i] = (8 - dec->vector[i]) >> 3;
00166     }
00167     for(i = 0; i < 8; i++)
00168         dec->cvector[i] = (dec->cvector[i] * ts_230[i]) >> 15;
00169 
00170     dec->filtval = dec->vector[0];
00171 }
00172 
00173 static void truespeech_filters_merge(TSContext *dec)
00174 {
00175     int i;
00176 
00177     if(!dec->flag){
00178         for(i = 0; i < 8; i++){
00179             dec->filters[i + 0] = dec->prevfilt[i];
00180             dec->filters[i + 8] = dec->prevfilt[i];
00181         }
00182     }else{
00183         for(i = 0; i < 8; i++){
00184             dec->filters[i + 0]=(dec->cvector[i] * 21846 + dec->prevfilt[i] * 10923 + 16384) >> 15;
00185             dec->filters[i + 8]=(dec->cvector[i] * 10923 + dec->prevfilt[i] * 21846 + 16384) >> 15;
00186         }
00187     }
00188     for(i = 0; i < 8; i++){
00189         dec->filters[i + 16] = dec->cvector[i];
00190         dec->filters[i + 24] = dec->cvector[i];
00191     }
00192 }
00193 
00194 static void truespeech_apply_twopoint_filter(TSContext *dec, int quart)
00195 {
00196     int16_t tmp[146 + 60], *ptr0, *ptr1;
00197     const int16_t *filter;
00198     int i, t, off;
00199 
00200     t = dec->offset2[quart];
00201     if(t == 127){
00202         memset(dec->newvec, 0, 60 * 2);
00203         return;
00204     }
00205     for(i = 0; i < 146; i++)
00206         tmp[i] = dec->filtbuf[i];
00207     off = (t / 25) + dec->offset1[quart >> 1] + 18;
00208     ptr0 = tmp + 145 - off;
00209     ptr1 = tmp + 146;
00210     filter = (const int16_t*)ts_240 + (t % 25) * 2;
00211     for(i = 0; i < 60; i++){
00212         t = (ptr0[0] * filter[0] + ptr0[1] * filter[1] + 0x2000) >> 14;
00213         ptr0++;
00214         dec->newvec[i] = t;
00215         ptr1[i] = t;
00216     }
00217 }
00218 
00219 static void truespeech_place_pulses(TSContext *dec, int16_t *out, int quart)
00220 {
00221     int16_t tmp[7];
00222     int i, j, t;
00223     const int16_t *ptr1;
00224     int16_t *ptr2;
00225     int coef;
00226 
00227     memset(out, 0, 60 * 2);
00228     for(i = 0; i < 7; i++) {
00229         t = dec->pulseval[quart] & 3;
00230         dec->pulseval[quart] >>= 2;
00231         tmp[6 - i] = ts_562[dec->pulseoff[quart] * 4 + t];
00232     }
00233 
00234     coef = dec->pulsepos[quart] >> 15;
00235     ptr1 = (const int16_t*)ts_140 + 30;
00236     ptr2 = tmp;
00237     for(i = 0, j = 3; (i < 30) && (j > 0); i++){
00238         t = *ptr1++;
00239         if(coef >= t)
00240             coef -= t;
00241         else{
00242             out[i] = *ptr2++;
00243             ptr1 += 30;
00244             j--;
00245         }
00246     }
00247     coef = dec->pulsepos[quart] & 0x7FFF;
00248     ptr1 = (const int16_t*)ts_140;
00249     for(i = 30, j = 4; (i < 60) && (j > 0); i++){
00250         t = *ptr1++;
00251         if(coef >= t)
00252             coef -= t;
00253         else{
00254             out[i] = *ptr2++;
00255             ptr1 += 30;
00256             j--;
00257         }
00258     }
00259 
00260 }
00261 
00262 static void truespeech_update_filters(TSContext *dec, int16_t *out, int quart)
00263 {
00264     int i;
00265 
00266     for(i = 0; i < 86; i++)
00267         dec->filtbuf[i] = dec->filtbuf[i + 60];
00268     for(i = 0; i < 60; i++){
00269         dec->filtbuf[i + 86] = out[i] + dec->newvec[i] - (dec->newvec[i] >> 3);
00270         out[i] += dec->newvec[i];
00271     }
00272 }
00273 
00274 static void truespeech_synth(TSContext *dec, int16_t *out, int quart)
00275 {
00276     int i,k;
00277     int t[8];
00278     int16_t *ptr0, *ptr1;
00279 
00280     ptr0 = dec->tmp1;
00281     ptr1 = dec->filters + quart * 8;
00282     for(i = 0; i < 60; i++){
00283         int sum = 0;
00284         for(k = 0; k < 8; k++)
00285             sum += ptr0[k] * ptr1[k];
00286         sum = (sum + (out[i] << 12) + 0x800) >> 12;
00287         out[i] = av_clip(sum, -0x7FFE, 0x7FFE);
00288         for(k = 7; k > 0; k--)
00289             ptr0[k] = ptr0[k - 1];
00290         ptr0[0] = out[i];
00291     }
00292 
00293     for(i = 0; i < 8; i++)
00294         t[i] = (ts_5E2[i] * ptr1[i]) >> 15;
00295 
00296     ptr0 = dec->tmp2;
00297     for(i = 0; i < 60; i++){
00298         int sum = 0;
00299         for(k = 0; k < 8; k++)
00300             sum += ptr0[k] * t[k];
00301         for(k = 7; k > 0; k--)
00302             ptr0[k] = ptr0[k - 1];
00303         ptr0[0] = out[i];
00304         out[i] = ((out[i] << 12) - sum) >> 12;
00305     }
00306 
00307     for(i = 0; i < 8; i++)
00308         t[i] = (ts_5F2[i] * ptr1[i]) >> 15;
00309 
00310     ptr0 = dec->tmp3;
00311     for(i = 0; i < 60; i++){
00312         int sum = out[i] << 12;
00313         for(k = 0; k < 8; k++)
00314             sum += ptr0[k] * t[k];
00315         for(k = 7; k > 0; k--)
00316             ptr0[k] = ptr0[k - 1];
00317         ptr0[0] = av_clip((sum + 0x800) >> 12, -0x7FFE, 0x7FFE);
00318 
00319         sum = ((ptr0[1] * (dec->filtval - (dec->filtval >> 2))) >> 4) + sum;
00320         sum = sum - (sum >> 3);
00321         out[i] = av_clip((sum + 0x800) >> 12, -0x7FFE, 0x7FFE);
00322     }
00323 }
00324 
00325 static void truespeech_save_prevvec(TSContext *c)
00326 {
00327     int i;
00328 
00329     for(i = 0; i < 8; i++)
00330         c->prevfilt[i] = c->cvector[i];
00331 }
00332 
00333 static int truespeech_decode_frame(AVCodecContext *avctx,
00334                 void *data, int *data_size,
00335                 AVPacket *avpkt)
00336 {
00337     const uint8_t *buf = avpkt->data;
00338     int buf_size = avpkt->size;
00339     TSContext *c = avctx->priv_data;
00340 
00341     int i, j;
00342     short *samples = data;
00343     int consumed = 0;
00344     int16_t out_buf[240];
00345     int iterations;
00346 
00347     if (!buf_size)
00348         return 0;
00349 
00350     iterations = FFMIN(buf_size / 32, *data_size / 480);
00351     for(j = 0; j < iterations; j++) {
00352         truespeech_read_frame(c, buf + consumed);
00353         consumed += 32;
00354 
00355         truespeech_correlate_filter(c);
00356         truespeech_filters_merge(c);
00357 
00358         memset(out_buf, 0, 240 * 2);
00359         for(i = 0; i < 4; i++) {
00360             truespeech_apply_twopoint_filter(c, i);
00361             truespeech_place_pulses(c, out_buf + i * 60, i);
00362             truespeech_update_filters(c, out_buf + i * 60, i);
00363             truespeech_synth(c, out_buf + i * 60, i);
00364         }
00365 
00366         truespeech_save_prevvec(c);
00367 
00368         /* finally output decoded frame */
00369         for(i = 0; i < 240; i++)
00370             *samples++ = out_buf[i];
00371 
00372     }
00373 
00374     *data_size = consumed * 15;
00375 
00376     return consumed;
00377 }
00378 
00379 AVCodec truespeech_decoder = {
00380     "truespeech",
00381     AVMEDIA_TYPE_AUDIO,
00382     CODEC_ID_TRUESPEECH,
00383     sizeof(TSContext),
00384     truespeech_decode_init,
00385     NULL,
00386     NULL,
00387     truespeech_decode_frame,
00388     .long_name = NULL_IF_CONFIG_SMALL("DSP Group TrueSpeech"),
00389 };

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