Statistics
| Branch: | Revision:

ffmpeg / libavcodec / truespeech.c @ 5509bffa

History | View | Annotate | Download (9.75 KB)

1
/*
2
 * DSP Group TrueSpeech compatible decoder
3
 * Copyright (c) 2005 Konstantin Shishkov
4
 *
5
 * This library is free software; you can redistribute it and/or
6
 * modify it under the terms of the GNU Lesser General Public
7
 * License as published by the Free Software Foundation; either
8
 * version 2 of the License, or (at your option) any later version.
9
 *
10
 * This library is distributed in the hope that it will be useful,
11
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13
 * Lesser General Public License for more details.
14
 *
15
 * You should have received a copy of the GNU Lesser General Public
16
 * License along with this library; if not, write to the Free Software
17
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18
 */
19
#include "avcodec.h"
20

    
21
#include "truespeech_data.h"
22
/**
23
 * @file truespeech.c
24
 * TrueSpeech decoder.
25
 */
26

    
27
/**
28
 * TrueSpeech decoder context
29
 */
30
typedef struct {
31
    /* input data */
32
    int16_t vector[8];  //< input vector: 5/5/4/4/4/3/3/3
33
    int offset1[2];     //< 8-bit value, used in one copying offset
34
    int offset2[4];     //< 7-bit value, encodes offsets for copying and for two-point filter
35
    int pulseoff[4];    //< 4-bit offset of pulse values block
36
    int pulsepos[4];    //< 27-bit variable, encodes 7 pulse positions
37
    int pulseval[4];    //< 7x2-bit pulse values
38
    int flag;           //< 1-bit flag, shows how to choose filters
39
    /* temporary data */
40
    int filtbuf[146];   // some big vector used for storing filters
41
    int prevfilt[8];    // filter from previous frame
42
    int16_t tmp1[8];    // coefficients for adding to out
43
    int16_t tmp2[8];    // coefficients for adding to out
44
    int16_t tmp3[8];    // coefficients for adding to out
45
    int16_t cvector[8]; // correlated input vector
46
    int filtval;        // gain value for one function
47
    int16_t newvec[60]; // tmp vector
48
    int16_t filters[32]; // filters for every subframe
49
} TSContext;
50

    
51
static int truespeech_decode_init(AVCodecContext * avctx)
52
{
53
//    TSContext *c = avctx->priv_data;
54

    
55
    return 0;
56
}
57

    
58
static void truespeech_read_frame(TSContext *dec, uint8_t *input)
59
{
60
    uint32_t t;
61

    
62
    /* first dword */
63
    t = LE_32(input);
64
    input += 4;
65

    
66
    dec->flag = t & 1;
67

    
68
    dec->vector[0] = ts_codebook[0][(t >>  1) & 0x1F];
69
    dec->vector[1] = ts_codebook[1][(t >>  6) & 0x1F];
70
    dec->vector[2] = ts_codebook[2][(t >> 11) &  0xF];
71
    dec->vector[3] = ts_codebook[3][(t >> 15) &  0xF];
72
    dec->vector[4] = ts_codebook[4][(t >> 19) &  0xF];
73
    dec->vector[5] = ts_codebook[5][(t >> 23) &  0x7];
74
    dec->vector[6] = ts_codebook[6][(t >> 26) &  0x7];
75
    dec->vector[7] = ts_codebook[7][(t >> 29) &  0x7];
76

    
77
    /* second dword */
78
    t = LE_32(input);
79
    input += 4;
80

    
81
    dec->offset2[0] = (t >>  0) & 0x7F;
82
    dec->offset2[1] = (t >>  7) & 0x7F;
83
    dec->offset2[2] = (t >> 14) & 0x7F;
84
    dec->offset2[3] = (t >> 21) & 0x7F;
85

    
86
    dec->offset1[0] = ((t >> 28) & 0xF) << 4;
87

    
88
    /* third dword */
89
    t = LE_32(input);
90
    input += 4;
91

    
92
    dec->pulseval[0] = (t >>  0) & 0x3FFF;
93
    dec->pulseval[1] = (t >> 14) & 0x3FFF;
94

    
95
    dec->offset1[1] = (t >> 28) & 0x0F;
96

    
97
    /* fourth dword */
98
    t = LE_32(input);
99
    input += 4;
100

    
101
    dec->pulseval[2] = (t >>  0) & 0x3FFF;
102
    dec->pulseval[3] = (t >> 14) & 0x3FFF;
103

    
104
    dec->offset1[1] |= ((t >> 28) & 0x0F) << 4;
105

    
106
    /* fifth dword */
107
    t = LE_32(input);
108
    input += 4;
109

    
110
    dec->pulsepos[0] = (t >> 4) & 0x7FFFFFF;
111

    
112
    dec->pulseoff[0] = (t >> 0) & 0xF;
113

    
114
    dec->offset1[0] |= (t >> 31) & 1;
115

    
116
    /* sixth dword */
117
    t = LE_32(input);
118
    input += 4;
119

    
120
    dec->pulsepos[1] = (t >> 4) & 0x7FFFFFF;
121

    
122
    dec->pulseoff[1] = (t >> 0) & 0xF;
123

    
124
    dec->offset1[0] |= ((t >> 31) & 1) << 1;
125

    
126
    /* seventh dword */
127
    t = LE_32(input);
128
    input += 4;
129

    
130
    dec->pulsepos[2] = (t >> 4) & 0x7FFFFFF;
131

    
132
    dec->pulseoff[2] = (t >> 0) & 0xF;
133

    
134
    dec->offset1[0] |= ((t >> 31) & 1) << 2;
135

    
136
    /* eighth dword */
137
    t = LE_32(input);
138
    input += 4;
139

    
140
    dec->pulsepos[3] = (t >> 4) & 0x7FFFFFF;
141

    
142
    dec->pulseoff[3] = (t >> 0) & 0xF;
143

    
144
    dec->offset1[0] |= ((t >> 31) & 1) << 3;
145

    
146
}
147

    
148
static void truespeech_correlate_filter(TSContext *dec)
149
{
150
    int16_t tmp[8];
151
    int i, j;
152

    
153
    for(i = 0; i < 8; i++){
154
        if(i > 0){
155
            memcpy(tmp, dec->cvector, i * 2);
156
            for(j = 0; j < i; j++)
157
                dec->cvector[j] = ((tmp[i - j - 1] * dec->vector[i]) +
158
                                   (dec->cvector[j] << 15) + 0x4000) >> 15;
159
        }
160
        dec->cvector[i] = (8 - dec->vector[i]) >> 3;
161
    }
162
    for(i = 0; i < 8; i++)
163
        dec->cvector[i] = (dec->cvector[i] * ts_230[i]) >> 15;
164

    
165
    dec->filtval = dec->vector[0];
166
}
167

    
168
static void truespeech_filters_merge(TSContext *dec)
169
{
170
    int i;
171

    
172
    if(!dec->flag){
173
        for(i = 0; i < 8; i++){
174
            dec->filters[i + 0] = dec->prevfilt[i];
175
            dec->filters[i + 8] = dec->prevfilt[i];
176
        }
177
    }else{
178
        for(i = 0; i < 8; i++){
179
            dec->filters[i + 0]=(dec->cvector[i] * 21846 + dec->prevfilt[i] * 10923 + 16384) >> 15;
180
            dec->filters[i + 8]=(dec->cvector[i] * 10923 + dec->prevfilt[i] * 21846 + 16384) >> 15;
181
        }
182
    }
183
    for(i = 0; i < 8; i++){
184
        dec->filters[i + 16] = dec->cvector[i];
185
        dec->filters[i + 24] = dec->cvector[i];
186
    }
187
}
188

    
189
static void truespeech_apply_twopoint_filter(TSContext *dec, int quart)
190
{
191
    int16_t tmp[146 + 60], *ptr0, *ptr1, *filter;
192
    int i, t, off;
193

    
194
    t = dec->offset2[quart];
195
    if(t == 127){
196
        memset(dec->newvec, 0, 60 * 2);
197
        return;
198
    }
199
    for(i = 0; i < 146; i++)
200
        tmp[i] = dec->filtbuf[i];
201
    off = (t / 25) + dec->offset1[quart >> 1] + 18;
202
    ptr0 = tmp + 145 - off;
203
    ptr1 = tmp + 146;
204
    filter = ts_240 + (t % 25) * 2;
205
    for(i = 0; i < 60; i++){
206
        t = (ptr0[0] * filter[0] + ptr0[1] * filter[1] + 0x2000) >> 14;
207
        ptr0++;
208
        dec->newvec[i] = t;
209
        ptr1[i] = t;
210
    }
211
}
212

    
213
static void truespeech_place_pulses(TSContext *dec, int16_t *out, int quart)
214
{
215
    int16_t tmp[7];
216
    int i, j, t;
217
    int16_t *ptr1, *ptr2;
218
    int coef;
219

    
220
    memset(out, 0, 60 * 2);
221
    for(i = 0; i < 7; i++) {
222
        t = dec->pulseval[quart] & 3;
223
        dec->pulseval[quart] >>= 2;
224
        tmp[6 - i] = ts_562[dec->pulseoff[quart] * 4 + t];
225
    }
226

    
227
    coef = dec->pulsepos[quart] >> 15;
228
    ptr1 = ts_140 + 30;
229
    ptr2 = tmp;
230
    for(i = 0, j = 3; (i < 30) && (j > 0); i++){
231
        t = *ptr1++;
232
        if(coef >= t)
233
            coef -= t;
234
        else{
235
            out[i] = *ptr2++;
236
            ptr1 += 30;
237
            j--;
238
        }
239
    }
240
    coef = dec->pulsepos[quart] & 0x7FFF;
241
    ptr1 = ts_140;
242
    for(i = 30, j = 4; (i < 60) && (j > 0); i++){
243
        t = *ptr1++;
244
        if(coef >= t)
245
            coef -= t;
246
        else{
247
            out[i] = *ptr2++;
248
            ptr1 += 30;
249
            j--;
250
        }
251
    }
252

    
253
}
254

    
255
static void truespeech_update_filters(TSContext *dec, int16_t *out, int quart)
256
{
257
    int i;
258

    
259
    for(i = 0; i < 86; i++)
260
        dec->filtbuf[i] = dec->filtbuf[i + 60];
261
    for(i = 0; i < 60; i++){
262
        dec->filtbuf[i + 86] = out[i] + dec->newvec[i] - (dec->newvec[i] >> 3);
263
        out[i] += dec->newvec[i];
264
    }
265
}
266

    
267
static void truespeech_synth(TSContext *dec, int16_t *out, int quart)
268
{
269
    int i,k;
270
    int t[8];
271
    int16_t *ptr0, *ptr1;
272

    
273
    ptr0 = dec->tmp1;
274
    ptr1 = dec->filters + quart * 8;
275
    for(i = 0; i < 60; i++){
276
        int sum = 0;
277
        for(k = 0; k < 8; k++)
278
            sum += ptr0[k] * ptr1[k];
279
        sum = (sum + (out[i] << 12) + 0x800) >> 12;
280
        out[i] = clip(sum, -0x7FFE, 0x7FFE);
281
        for(k = 7; k > 0; k--)
282
            ptr0[k] = ptr0[k - 1];
283
        ptr0[0] = out[i];
284
    }
285

    
286
    for(i = 0; i < 8; i++)
287
        t[i] = (ts_5E2[i] * ptr1[i]) >> 15;
288

    
289
    ptr0 = dec->tmp2;
290
    for(i = 0; i < 60; i++){
291
        int sum = 0;
292
        for(k = 0; k < 8; k++)
293
            sum += ptr0[k] * t[k];
294
        for(k = 7; k > 0; k--)
295
            ptr0[k] = ptr0[k - 1];
296
        ptr0[0] = out[i];
297
        out[i] = ((out[i] << 12) - sum) >> 12;
298
    }
299

    
300
    for(i = 0; i < 8; i++)
301
        t[i] = (ts_5F2[i] * ptr1[i]) >> 15;
302

    
303
    ptr0 = dec->tmp3;
304
    for(i = 0; i < 60; i++){
305
        int sum = out[i] << 12;
306
        for(k = 0; k < 8; k++)
307
            sum += ptr0[k] * t[k];
308
        for(k = 7; k > 0; k--)
309
            ptr0[k] = ptr0[k - 1];
310
        ptr0[0] = clip((sum + 0x800) >> 12, -0x7FFE, 0x7FFE);
311

    
312
        sum = ((ptr0[1] * (dec->filtval - (dec->filtval >> 2))) >> 4) + sum;
313
        sum = sum - (sum >> 3);
314
        out[i] = clip((sum + 0x800) >> 12, -0x7FFE, 0x7FFE);
315
    }
316
}
317

    
318
static void truespeech_save_prevvec(TSContext *c)
319
{
320
    int i;
321

    
322
    for(i = 0; i < 8; i++)
323
        c->prevfilt[i] = c->cvector[i];
324
}
325

    
326
static int truespeech_decode_frame(AVCodecContext *avctx,
327
                void *data, int *data_size,
328
                uint8_t *buf, int buf_size)
329
{
330
    TSContext *c = avctx->priv_data;
331

    
332
    int i;
333
    short *samples = data;
334
    int consumed = 0;
335
    int16_t out_buf[240];
336

    
337
    if (!buf_size)
338
        return 0;
339

    
340
    while (consumed < buf_size) {
341
        truespeech_read_frame(c, buf + consumed);
342
        consumed += 32;
343

    
344
        truespeech_correlate_filter(c);
345
        truespeech_filters_merge(c);
346

    
347
        memset(out_buf, 0, 240 * 2);
348
        for(i = 0; i < 4; i++) {
349
            truespeech_apply_twopoint_filter(c, i);
350
            truespeech_place_pulses(c, out_buf + i * 60, i);
351
            truespeech_update_filters(c, out_buf + i * 60, i);
352
            truespeech_synth(c, out_buf + i * 60, i);
353
        }
354

    
355
        truespeech_save_prevvec(c);
356

    
357
        /* finally output decoded frame */
358
        for(i = 0; i < 240; i++)
359
            *samples++ = out_buf[i];
360

    
361
    }
362

    
363
    *data_size = consumed * 15;
364

    
365
    return buf_size;
366
}
367

    
368
AVCodec truespeech_decoder = {
369
    "truespeech",
370
    CODEC_TYPE_AUDIO,
371
    CODEC_ID_TRUESPEECH,
372
    sizeof(TSContext),
373
    truespeech_decode_init,
374
    NULL,
375
    NULL,
376
    truespeech_decode_frame,
377
};