truespeech: fix invalid reads in truespeech_apply_twopoint_filter()
[libav.git] / libavcodec / truespeech.c
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 */
36 typedef 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
60 static 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
79 static 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
127 static 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
147 static 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
168 static 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
194 static 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
237 static 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
248 static 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
299 static 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
307 static 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
360 AVCodec 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 };