1 /*
2 * TwinVQ decoder
3 * Copyright (c) 2009 Vitor Sessak
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include <math.h>
23 #include <stdint.h>
24
25 #include "libavutil/channel_layout.h"
26 #include "libavutil/float_dsp.h"
27 #include "avcodec.h"
28 #include "fft.h"
29 #include "internal.h"
30 #include "lsp.h"
31 #include "sinewin.h"
32 #include "twinvq.h"
33
34 /**
35 * Evaluate a single LPC amplitude spectrum envelope coefficient from the line
36 * spectrum pairs.
37 *
38 * @param lsp a vector of the cosine of the LSP values
39 * @param cos_val cos(PI*i/N) where i is the index of the LPC amplitude
40 * @param order the order of the LSP (and the size of the *lsp buffer). Must
41 * be a multiple of four.
42 * @return the LPC value
43 *
44 * @todo reuse code from Vorbis decoder: vorbis_floor0_decode
45 */
eval_lpc_spectrum(const float * lsp,float cos_val,int order)46 static float eval_lpc_spectrum(const float *lsp, float cos_val, int order)
47 {
48 int j;
49 float p = 0.5f;
50 float q = 0.5f;
51 float two_cos_w = 2.0f * cos_val;
52
53 for (j = 0; j + 1 < order; j += 2 * 2) {
54 // Unroll the loop once since order is a multiple of four
55 q *= lsp[j] - two_cos_w;
56 p *= lsp[j + 1] - two_cos_w;
57
58 q *= lsp[j + 2] - two_cos_w;
59 p *= lsp[j + 3] - two_cos_w;
60 }
61
62 p *= p * (2.0f - two_cos_w);
63 q *= q * (2.0f + two_cos_w);
64
65 return 0.5 / (p + q);
66 }
67
68 /**
69 * Evaluate the LPC amplitude spectrum envelope from the line spectrum pairs.
70 */
eval_lpcenv(TwinVQContext * tctx,const float * cos_vals,float * lpc)71 static void eval_lpcenv(TwinVQContext *tctx, const float *cos_vals, float *lpc)
72 {
73 int i;
74 const TwinVQModeTab *mtab = tctx->mtab;
75 int size_s = mtab->size / mtab->fmode[TWINVQ_FT_SHORT].sub;
76
77 for (i = 0; i < size_s / 2; i++) {
78 float cos_i = tctx->cos_tabs[0][i];
79 lpc[i] = eval_lpc_spectrum(cos_vals, cos_i, mtab->n_lsp);
80 lpc[size_s - i - 1] = eval_lpc_spectrum(cos_vals, -cos_i, mtab->n_lsp);
81 }
82 }
83
interpolate(float * out,float v1,float v2,int size)84 static void interpolate(float *out, float v1, float v2, int size)
85 {
86 int i;
87 float step = (v1 - v2) / (size + 1);
88
89 for (i = 0; i < size; i++) {
90 v2 += step;
91 out[i] = v2;
92 }
93 }
94
get_cos(int idx,int part,const float * cos_tab,int size)95 static inline float get_cos(int idx, int part, const float *cos_tab, int size)
96 {
97 return part ? -cos_tab[size - idx - 1]
98 : cos_tab[idx];
99 }
100
101 /**
102 * Evaluate the LPC amplitude spectrum envelope from the line spectrum pairs.
103 * Probably for speed reasons, the coefficients are evaluated as
104 * siiiibiiiisiiiibiiiisiiiibiiiisiiiibiiiis ...
105 * where s is an evaluated value, i is a value interpolated from the others
106 * and b might be either calculated or interpolated, depending on an
107 * unexplained condition.
108 *
109 * @param step the size of a block "siiiibiiii"
110 * @param in the cosine of the LSP data
111 * @param part is 0 for 0...PI (positive cosine values) and 1 for PI...2PI
112 * (negative cosine values)
113 * @param size the size of the whole output
114 */
eval_lpcenv_or_interp(TwinVQContext * tctx,enum TwinVQFrameType ftype,float * out,const float * in,int size,int step,int part)115 static inline void eval_lpcenv_or_interp(TwinVQContext *tctx,
116 enum TwinVQFrameType ftype,
117 float *out, const float *in,
118 int size, int step, int part)
119 {
120 int i;
121 const TwinVQModeTab *mtab = tctx->mtab;
122 const float *cos_tab = tctx->cos_tabs[ftype];
123
124 // Fill the 's'
125 for (i = 0; i < size; i += step)
126 out[i] =
127 eval_lpc_spectrum(in,
128 get_cos(i, part, cos_tab, size),
129 mtab->n_lsp);
130
131 // Fill the 'iiiibiiii'
132 for (i = step; i <= size - 2 * step; i += step) {
133 if (out[i + step] + out[i - step] > 1.95 * out[i] ||
134 out[i + step] >= out[i - step]) {
135 interpolate(out + i - step + 1, out[i], out[i - step], step - 1);
136 } else {
137 out[i - step / 2] =
138 eval_lpc_spectrum(in,
139 get_cos(i - step / 2, part, cos_tab, size),
140 mtab->n_lsp);
141 interpolate(out + i - step + 1, out[i - step / 2],
142 out[i - step], step / 2 - 1);
143 interpolate(out + i - step / 2 + 1, out[i],
144 out[i - step / 2], step / 2 - 1);
145 }
146 }
147
148 interpolate(out + size - 2 * step + 1, out[size - step],
149 out[size - 2 * step], step - 1);
150 }
151
eval_lpcenv_2parts(TwinVQContext * tctx,enum TwinVQFrameType ftype,const float * buf,float * lpc,int size,int step)152 static void eval_lpcenv_2parts(TwinVQContext *tctx, enum TwinVQFrameType ftype,
153 const float *buf, float *lpc,
154 int size, int step)
155 {
156 eval_lpcenv_or_interp(tctx, ftype, lpc, buf, size / 2, step, 0);
157 eval_lpcenv_or_interp(tctx, ftype, lpc + size / 2, buf, size / 2,
158 2 * step, 1);
159
160 interpolate(lpc + size / 2 - step + 1, lpc[size / 2],
161 lpc[size / 2 - step], step);
162
163 twinvq_memset_float(lpc + size - 2 * step + 1, lpc[size - 2 * step],
164 2 * step - 1);
165 }
166
167 /**
168 * Inverse quantization. Read CB coefficients for cb1 and cb2 from the
169 * bitstream, sum the corresponding vectors and write the result to *out
170 * after permutation.
171 */
dequant(TwinVQContext * tctx,const uint8_t * cb_bits,float * out,enum TwinVQFrameType ftype,const int16_t * cb0,const int16_t * cb1,int cb_len)172 static void dequant(TwinVQContext *tctx, const uint8_t *cb_bits, float *out,
173 enum TwinVQFrameType ftype,
174 const int16_t *cb0, const int16_t *cb1, int cb_len)
175 {
176 int pos = 0;
177 int i, j;
178
179 for (i = 0; i < tctx->n_div[ftype]; i++) {
180 int tmp0, tmp1;
181 int sign0 = 1;
182 int sign1 = 1;
183 const int16_t *tab0, *tab1;
184 int length = tctx->length[ftype][i >= tctx->length_change[ftype]];
185 int bitstream_second_part = (i >= tctx->bits_main_spec_change[ftype]);
186
187 int bits = tctx->bits_main_spec[0][ftype][bitstream_second_part];
188 tmp0 = *cb_bits++;
189 if (bits == 7) {
190 if (tmp0 & 0x40)
191 sign0 = -1;
192 tmp0 &= 0x3F;
193 }
194
195 bits = tctx->bits_main_spec[1][ftype][bitstream_second_part];
196 tmp1 = *cb_bits++;
197 if (bits == 7) {
198 if (tmp1 & 0x40)
199 sign1 = -1;
200 tmp1 &= 0x3F;
201 }
202
203 tab0 = cb0 + tmp0 * cb_len;
204 tab1 = cb1 + tmp1 * cb_len;
205
206 for (j = 0; j < length; j++)
207 out[tctx->permut[ftype][pos + j]] = sign0 * tab0[j] +
208 sign1 * tab1[j];
209
210 pos += length;
211 }
212 }
213
dec_gain(TwinVQContext * tctx,enum TwinVQFrameType ftype,float * out)214 static void dec_gain(TwinVQContext *tctx,
215 enum TwinVQFrameType ftype, float *out)
216 {
217 const TwinVQModeTab *mtab = tctx->mtab;
218 const TwinVQFrameData *bits = &tctx->bits[tctx->cur_frame];
219 int i, j;
220 int sub = mtab->fmode[ftype].sub;
221 float step = TWINVQ_AMP_MAX / ((1 << TWINVQ_GAIN_BITS) - 1);
222 float sub_step = TWINVQ_SUB_AMP_MAX / ((1 << TWINVQ_SUB_GAIN_BITS) - 1);
223
224 if (ftype == TWINVQ_FT_LONG) {
225 for (i = 0; i < tctx->avctx->channels; i++)
226 out[i] = (1.0 / (1 << 13)) *
227 twinvq_mulawinv(step * 0.5 + step * bits->gain_bits[i],
228 TWINVQ_AMP_MAX, TWINVQ_MULAW_MU);
229 } else {
230 for (i = 0; i < tctx->avctx->channels; i++) {
231 float val = (1.0 / (1 << 23)) *
232 twinvq_mulawinv(step * 0.5 + step * bits->gain_bits[i],
233 TWINVQ_AMP_MAX, TWINVQ_MULAW_MU);
234
235 for (j = 0; j < sub; j++)
236 out[i * sub + j] =
237 val * twinvq_mulawinv(sub_step * 0.5 +
238 sub_step * bits->sub_gain_bits[i * sub + j],
239 TWINVQ_SUB_AMP_MAX, TWINVQ_MULAW_MU);
240 }
241 }
242 }
243
244 /**
245 * Rearrange the LSP coefficients so that they have a minimum distance of
246 * min_dist. This function does it exactly as described in section of 3.2.4
247 * of the G.729 specification (but interestingly is different from what the
248 * reference decoder actually does).
249 */
rearrange_lsp(int order,float * lsp,float min_dist)250 static void rearrange_lsp(int order, float *lsp, float min_dist)
251 {
252 int i;
253 float min_dist2 = min_dist * 0.5;
254 for (i = 1; i < order; i++)
255 if (lsp[i] - lsp[i - 1] < min_dist) {
256 float avg = (lsp[i] + lsp[i - 1]) * 0.5;
257
258 lsp[i - 1] = avg - min_dist2;
259 lsp[i] = avg + min_dist2;
260 }
261 }
262
decode_lsp(TwinVQContext * tctx,int lpc_idx1,uint8_t * lpc_idx2,int lpc_hist_idx,float * lsp,float * hist)263 static void decode_lsp(TwinVQContext *tctx, int lpc_idx1, uint8_t *lpc_idx2,
264 int lpc_hist_idx, float *lsp, float *hist)
265 {
266 const TwinVQModeTab *mtab = tctx->mtab;
267 int i, j;
268
269 const float *cb = mtab->lspcodebook;
270 const float *cb2 = cb + (1 << mtab->lsp_bit1) * mtab->n_lsp;
271 const float *cb3 = cb2 + (1 << mtab->lsp_bit2) * mtab->n_lsp;
272
273 const int8_t funny_rounding[4] = {
274 -2,
275 mtab->lsp_split == 4 ? -2 : 1,
276 mtab->lsp_split == 4 ? -2 : 1,
277 0
278 };
279
280 j = 0;
281 for (i = 0; i < mtab->lsp_split; i++) {
282 int chunk_end = ((i + 1) * mtab->n_lsp + funny_rounding[i]) /
283 mtab->lsp_split;
284 for (; j < chunk_end; j++)
285 lsp[j] = cb[lpc_idx1 * mtab->n_lsp + j] +
286 cb2[lpc_idx2[i] * mtab->n_lsp + j];
287 }
288
289 rearrange_lsp(mtab->n_lsp, lsp, 0.0001);
290
291 for (i = 0; i < mtab->n_lsp; i++) {
292 float tmp1 = 1.0 - cb3[lpc_hist_idx * mtab->n_lsp + i];
293 float tmp2 = hist[i] * cb3[lpc_hist_idx * mtab->n_lsp + i];
294 hist[i] = lsp[i];
295 lsp[i] = lsp[i] * tmp1 + tmp2;
296 }
297
298 rearrange_lsp(mtab->n_lsp, lsp, 0.0001);
299 rearrange_lsp(mtab->n_lsp, lsp, 0.000095);
300 ff_sort_nearly_sorted_floats(lsp, mtab->n_lsp);
301 }
302
dec_lpc_spectrum_inv(TwinVQContext * tctx,float * lsp,enum TwinVQFrameType ftype,float * lpc)303 static void dec_lpc_spectrum_inv(TwinVQContext *tctx, float *lsp,
304 enum TwinVQFrameType ftype, float *lpc)
305 {
306 int i;
307 int size = tctx->mtab->size / tctx->mtab->fmode[ftype].sub;
308
309 for (i = 0; i < tctx->mtab->n_lsp; i++)
310 lsp[i] = 2 * cos(lsp[i]);
311
312 switch (ftype) {
313 case TWINVQ_FT_LONG:
314 eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 8);
315 break;
316 case TWINVQ_FT_MEDIUM:
317 eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 2);
318 break;
319 case TWINVQ_FT_SHORT:
320 eval_lpcenv(tctx, lsp, lpc);
321 break;
322 }
323 }
324
325 static const uint8_t wtype_to_wsize[] = { 0, 0, 2, 2, 2, 1, 0, 1, 1 };
326
imdct_and_window(TwinVQContext * tctx,enum TwinVQFrameType ftype,int wtype,float * in,float * prev,int ch)327 static void imdct_and_window(TwinVQContext *tctx, enum TwinVQFrameType ftype,
328 int wtype, float *in, float *prev, int ch)
329 {
330 FFTContext *mdct = &tctx->mdct_ctx[ftype];
331 const TwinVQModeTab *mtab = tctx->mtab;
332 int bsize = mtab->size / mtab->fmode[ftype].sub;
333 int size = mtab->size;
334 float *buf1 = tctx->tmp_buf;
335 int j, first_wsize, wsize; // Window size
336 float *out = tctx->curr_frame + 2 * ch * mtab->size;
337 float *out2 = out;
338 float *prev_buf;
339 int types_sizes[] = {
340 mtab->size / mtab->fmode[TWINVQ_FT_LONG].sub,
341 mtab->size / mtab->fmode[TWINVQ_FT_MEDIUM].sub,
342 mtab->size / (mtab->fmode[TWINVQ_FT_SHORT].sub * 2),
343 };
344
345 wsize = types_sizes[wtype_to_wsize[wtype]];
346 first_wsize = wsize;
347 prev_buf = prev + (size - bsize) / 2;
348
349 for (j = 0; j < mtab->fmode[ftype].sub; j++) {
350 int sub_wtype = ftype == TWINVQ_FT_MEDIUM ? 8 : wtype;
351
352 if (!j && wtype == 4)
353 sub_wtype = 4;
354 else if (j == mtab->fmode[ftype].sub - 1 && wtype == 7)
355 sub_wtype = 7;
356
357 wsize = types_sizes[wtype_to_wsize[sub_wtype]];
358
359 mdct->imdct_half(mdct, buf1 + bsize * j, in + bsize * j);
360
361 tctx->fdsp->vector_fmul_window(out2, prev_buf + (bsize - wsize) / 2,
362 buf1 + bsize * j,
363 ff_sine_windows[av_log2(wsize)],
364 wsize / 2);
365 out2 += wsize;
366
367 memcpy(out2, buf1 + bsize * j + wsize / 2,
368 (bsize - wsize / 2) * sizeof(float));
369
370 out2 += ftype == TWINVQ_FT_MEDIUM ? (bsize - wsize) / 2 : bsize - wsize;
371
372 prev_buf = buf1 + bsize * j + bsize / 2;
373 }
374
375 tctx->last_block_pos[ch] = (size + first_wsize) / 2;
376 }
377
imdct_output(TwinVQContext * tctx,enum TwinVQFrameType ftype,int wtype,float ** out,int offset)378 static void imdct_output(TwinVQContext *tctx, enum TwinVQFrameType ftype,
379 int wtype, float **out, int offset)
380 {
381 const TwinVQModeTab *mtab = tctx->mtab;
382 float *prev_buf = tctx->prev_frame + tctx->last_block_pos[0];
383 int size1, size2, i;
384 float *out1, *out2;
385
386 for (i = 0; i < tctx->avctx->channels; i++)
387 imdct_and_window(tctx, ftype, wtype,
388 tctx->spectrum + i * mtab->size,
389 prev_buf + 2 * i * mtab->size,
390 i);
391
392 if (!out)
393 return;
394
395 size2 = tctx->last_block_pos[0];
396 size1 = mtab->size - size2;
397
398 out1 = &out[0][0] + offset;
399 memcpy(out1, prev_buf, size1 * sizeof(*out1));
400 memcpy(out1 + size1, tctx->curr_frame, size2 * sizeof(*out1));
401
402 if (tctx->avctx->channels == 2) {
403 out2 = &out[1][0] + offset;
404 memcpy(out2, &prev_buf[2 * mtab->size],
405 size1 * sizeof(*out2));
406 memcpy(out2 + size1, &tctx->curr_frame[2 * mtab->size],
407 size2 * sizeof(*out2));
408 tctx->fdsp->butterflies_float(out1, out2, mtab->size);
409 }
410 }
411
read_and_decode_spectrum(TwinVQContext * tctx,float * out,enum TwinVQFrameType ftype)412 static void read_and_decode_spectrum(TwinVQContext *tctx, float *out,
413 enum TwinVQFrameType ftype)
414 {
415 const TwinVQModeTab *mtab = tctx->mtab;
416 TwinVQFrameData *bits = &tctx->bits[tctx->cur_frame];
417 int channels = tctx->avctx->channels;
418 int sub = mtab->fmode[ftype].sub;
419 int block_size = mtab->size / sub;
420 float gain[TWINVQ_CHANNELS_MAX * TWINVQ_SUBBLOCKS_MAX];
421 float ppc_shape[TWINVQ_PPC_SHAPE_LEN_MAX * TWINVQ_CHANNELS_MAX * 4];
422
423 int i, j;
424
425 dequant(tctx, bits->main_coeffs, out, ftype,
426 mtab->fmode[ftype].cb0, mtab->fmode[ftype].cb1,
427 mtab->fmode[ftype].cb_len_read);
428
429 dec_gain(tctx, ftype, gain);
430
431 if (ftype == TWINVQ_FT_LONG) {
432 int cb_len_p = (tctx->n_div[3] + mtab->ppc_shape_len * channels - 1) /
433 tctx->n_div[3];
434 dequant(tctx, bits->ppc_coeffs, ppc_shape,
435 TWINVQ_FT_PPC, mtab->ppc_shape_cb,
436 mtab->ppc_shape_cb + cb_len_p * TWINVQ_PPC_SHAPE_CB_SIZE,
437 cb_len_p);
438 }
439
440 for (i = 0; i < channels; i++) {
441 float *chunk = out + mtab->size * i;
442 float lsp[TWINVQ_LSP_COEFS_MAX];
443
444 for (j = 0; j < sub; j++) {
445 tctx->dec_bark_env(tctx, bits->bark1[i][j],
446 bits->bark_use_hist[i][j], i,
447 tctx->tmp_buf, gain[sub * i + j], ftype);
448
449 tctx->fdsp->vector_fmul(chunk + block_size * j,
450 chunk + block_size * j,
451 tctx->tmp_buf, block_size);
452 }
453
454 if (ftype == TWINVQ_FT_LONG)
455 tctx->decode_ppc(tctx, bits->p_coef[i], bits->g_coef[i],
456 ppc_shape + i * mtab->ppc_shape_len, chunk);
457
458 decode_lsp(tctx, bits->lpc_idx1[i], bits->lpc_idx2[i],
459 bits->lpc_hist_idx[i], lsp, tctx->lsp_hist[i]);
460
461 dec_lpc_spectrum_inv(tctx, lsp, ftype, tctx->tmp_buf);
462
463 for (j = 0; j < mtab->fmode[ftype].sub; j++) {
464 tctx->fdsp->vector_fmul(chunk, chunk, tctx->tmp_buf, block_size);
465 chunk += block_size;
466 }
467 }
468 }
469
470 const enum TwinVQFrameType ff_twinvq_wtype_to_ftype_table[] = {
471 TWINVQ_FT_LONG, TWINVQ_FT_LONG, TWINVQ_FT_SHORT, TWINVQ_FT_LONG,
472 TWINVQ_FT_MEDIUM, TWINVQ_FT_LONG, TWINVQ_FT_LONG, TWINVQ_FT_MEDIUM,
473 TWINVQ_FT_MEDIUM
474 };
475
ff_twinvq_decode_frame(AVCodecContext * avctx,void * data,int * got_frame_ptr,AVPacket * avpkt)476 int ff_twinvq_decode_frame(AVCodecContext *avctx, void *data,
477 int *got_frame_ptr, AVPacket *avpkt)
478 {
479 AVFrame *frame = data;
480 const uint8_t *buf = avpkt->data;
481 int buf_size = avpkt->size;
482 TwinVQContext *tctx = avctx->priv_data;
483 const TwinVQModeTab *mtab = tctx->mtab;
484 float **out = NULL;
485 int ret;
486
487 /* get output buffer */
488 if (tctx->discarded_packets >= 2) {
489 frame->nb_samples = mtab->size * tctx->frames_per_packet;
490 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
491 return ret;
492 out = (float **)frame->extended_data;
493 }
494
495 if (buf_size < avctx->block_align) {
496 av_log(avctx, AV_LOG_ERROR,
497 "Frame too small (%d bytes). Truncated file?\n", buf_size);
498 return AVERROR(EINVAL);
499 }
500
501 if ((ret = tctx->read_bitstream(avctx, tctx, buf, buf_size)) < 0)
502 return ret;
503
504 for (tctx->cur_frame = 0; tctx->cur_frame < tctx->frames_per_packet;
505 tctx->cur_frame++) {
506 read_and_decode_spectrum(tctx, tctx->spectrum,
507 tctx->bits[tctx->cur_frame].ftype);
508
509 imdct_output(tctx, tctx->bits[tctx->cur_frame].ftype,
510 tctx->bits[tctx->cur_frame].window_type, out,
511 tctx->cur_frame * mtab->size);
512
513 FFSWAP(float *, tctx->curr_frame, tctx->prev_frame);
514 }
515
516 if (tctx->discarded_packets < 2) {
517 tctx->discarded_packets++;
518 *got_frame_ptr = 0;
519 return buf_size;
520 }
521
522 *got_frame_ptr = 1;
523
524 // VQF can deliver packets 1 byte greater than block align
525 if (buf_size == avctx->block_align + 1)
526 return buf_size;
527 return avctx->block_align;
528 }
529
530 /**
531 * Init IMDCT and windowing tables
532 */
init_mdct_win(TwinVQContext * tctx)533 static av_cold int init_mdct_win(TwinVQContext *tctx)
534 {
535 int i, j, ret;
536 const TwinVQModeTab *mtab = tctx->mtab;
537 int size_s = mtab->size / mtab->fmode[TWINVQ_FT_SHORT].sub;
538 int size_m = mtab->size / mtab->fmode[TWINVQ_FT_MEDIUM].sub;
539 int channels = tctx->avctx->channels;
540 float norm = channels == 1 ? 2.0 : 1.0;
541 int table_size = 2 * mtab->size * channels;
542
543 for (i = 0; i < 3; i++) {
544 int bsize = tctx->mtab->size / tctx->mtab->fmode[i].sub;
545 if ((ret = ff_mdct_init(&tctx->mdct_ctx[i], av_log2(bsize) + 1, 1,
546 -sqrt(norm / bsize) / (1 << 15))))
547 return ret;
548 }
549
550 if (!FF_ALLOC_TYPED_ARRAY(tctx->tmp_buf, mtab->size) ||
551 !FF_ALLOC_TYPED_ARRAY(tctx->spectrum, table_size) ||
552 !FF_ALLOC_TYPED_ARRAY(tctx->curr_frame, table_size) ||
553 !FF_ALLOC_TYPED_ARRAY(tctx->prev_frame, table_size))
554 return AVERROR(ENOMEM);
555
556 for (i = 0; i < 3; i++) {
557 int m = 4 * mtab->size / mtab->fmode[i].sub;
558 double freq = 2 * M_PI / m;
559 if (!FF_ALLOC_TYPED_ARRAY(tctx->cos_tabs[i], m / 4))
560 return AVERROR(ENOMEM);
561 for (j = 0; j <= m / 8; j++)
562 tctx->cos_tabs[i][j] = cos((2 * j + 1) * freq);
563 for (j = 1; j < m / 8; j++)
564 tctx->cos_tabs[i][m / 4 - j] = tctx->cos_tabs[i][j];
565 }
566
567 ff_init_ff_sine_windows(av_log2(size_m));
568 ff_init_ff_sine_windows(av_log2(size_s / 2));
569 ff_init_ff_sine_windows(av_log2(mtab->size));
570
571 return 0;
572 }
573
574 /**
575 * Interpret the data as if it were a num_blocks x line_len[0] matrix and for
576 * each line do a cyclic permutation, i.e.
577 * abcdefghijklm -> defghijklmabc
578 * where the amount to be shifted is evaluated depending on the column.
579 */
permutate_in_line(int16_t * tab,int num_vect,int num_blocks,int block_size,const uint8_t line_len[2],int length_div,enum TwinVQFrameType ftype)580 static void permutate_in_line(int16_t *tab, int num_vect, int num_blocks,
581 int block_size,
582 const uint8_t line_len[2], int length_div,
583 enum TwinVQFrameType ftype)
584 {
585 int i, j;
586
587 for (i = 0; i < line_len[0]; i++) {
588 int shift;
589
590 if (num_blocks == 1 ||
591 (ftype == TWINVQ_FT_LONG && num_vect % num_blocks) ||
592 (ftype != TWINVQ_FT_LONG && num_vect & 1) ||
593 i == line_len[1]) {
594 shift = 0;
595 } else if (ftype == TWINVQ_FT_LONG) {
596 shift = i;
597 } else
598 shift = i * i;
599
600 for (j = 0; j < num_vect && (j + num_vect * i < block_size * num_blocks); j++)
601 tab[i * num_vect + j] = i * num_vect + (j + shift) % num_vect;
602 }
603 }
604
605 /**
606 * Interpret the input data as in the following table:
607 *
608 * @verbatim
609 *
610 * abcdefgh
611 * ijklmnop
612 * qrstuvw
613 * x123456
614 *
615 * @endverbatim
616 *
617 * and transpose it, giving the output
618 * aiqxbjr1cks2dlt3emu4fvn5gow6hp
619 */
transpose_perm(int16_t * out,int16_t * in,int num_vect,const uint8_t line_len[2],int length_div)620 static void transpose_perm(int16_t *out, int16_t *in, int num_vect,
621 const uint8_t line_len[2], int length_div)
622 {
623 int i, j;
624 int cont = 0;
625
626 for (i = 0; i < num_vect; i++)
627 for (j = 0; j < line_len[i >= length_div]; j++)
628 out[cont++] = in[j * num_vect + i];
629 }
630
linear_perm(int16_t * out,int16_t * in,int n_blocks,int size)631 static void linear_perm(int16_t *out, int16_t *in, int n_blocks, int size)
632 {
633 int block_size = size / n_blocks;
634 int i;
635
636 for (i = 0; i < size; i++)
637 out[i] = block_size * (in[i] % n_blocks) + in[i] / n_blocks;
638 }
639
construct_perm_table(TwinVQContext * tctx,enum TwinVQFrameType ftype)640 static av_cold void construct_perm_table(TwinVQContext *tctx,
641 enum TwinVQFrameType ftype)
642 {
643 int block_size, size;
644 const TwinVQModeTab *mtab = tctx->mtab;
645 int16_t *tmp_perm = (int16_t *)tctx->tmp_buf;
646
647 if (ftype == TWINVQ_FT_PPC) {
648 size = tctx->avctx->channels;
649 block_size = mtab->ppc_shape_len;
650 } else {
651 size = tctx->avctx->channels * mtab->fmode[ftype].sub;
652 block_size = mtab->size / mtab->fmode[ftype].sub;
653 }
654
655 permutate_in_line(tmp_perm, tctx->n_div[ftype], size,
656 block_size, tctx->length[ftype],
657 tctx->length_change[ftype], ftype);
658
659 transpose_perm(tctx->permut[ftype], tmp_perm, tctx->n_div[ftype],
660 tctx->length[ftype], tctx->length_change[ftype]);
661
662 linear_perm(tctx->permut[ftype], tctx->permut[ftype], size,
663 size * block_size);
664 }
665
init_bitstream_params(TwinVQContext * tctx)666 static av_cold void init_bitstream_params(TwinVQContext *tctx)
667 {
668 const TwinVQModeTab *mtab = tctx->mtab;
669 int n_ch = tctx->avctx->channels;
670 int total_fr_bits = tctx->avctx->bit_rate * mtab->size /
671 tctx->avctx->sample_rate;
672
673 int lsp_bits_per_block = n_ch * (mtab->lsp_bit0 + mtab->lsp_bit1 +
674 mtab->lsp_split * mtab->lsp_bit2);
675
676 int ppc_bits = n_ch * (mtab->pgain_bit + mtab->ppc_shape_bit +
677 mtab->ppc_period_bit);
678
679 int bsize_no_main_cb[3], bse_bits[3], i;
680 enum TwinVQFrameType frametype;
681
682 for (i = 0; i < 3; i++)
683 // +1 for history usage switch
684 bse_bits[i] = n_ch *
685 (mtab->fmode[i].bark_n_coef *
686 mtab->fmode[i].bark_n_bit + 1);
687
688 bsize_no_main_cb[2] = bse_bits[2] + lsp_bits_per_block + ppc_bits +
689 TWINVQ_WINDOW_TYPE_BITS + n_ch * TWINVQ_GAIN_BITS;
690
691 for (i = 0; i < 2; i++)
692 bsize_no_main_cb[i] =
693 lsp_bits_per_block + n_ch * TWINVQ_GAIN_BITS +
694 TWINVQ_WINDOW_TYPE_BITS +
695 mtab->fmode[i].sub * (bse_bits[i] + n_ch * TWINVQ_SUB_GAIN_BITS);
696
697 if (tctx->codec == TWINVQ_CODEC_METASOUND && !tctx->is_6kbps) {
698 bsize_no_main_cb[1] += 2;
699 bsize_no_main_cb[2] += 2;
700 }
701
702 // The remaining bits are all used for the main spectrum coefficients
703 for (i = 0; i < 4; i++) {
704 int bit_size, vect_size;
705 int rounded_up, rounded_down, num_rounded_down, num_rounded_up;
706 if (i == 3) {
707 bit_size = n_ch * mtab->ppc_shape_bit;
708 vect_size = n_ch * mtab->ppc_shape_len;
709 } else {
710 bit_size = total_fr_bits - bsize_no_main_cb[i];
711 vect_size = n_ch * mtab->size;
712 }
713
714 tctx->n_div[i] = (bit_size + 13) / 14;
715
716 rounded_up = (bit_size + tctx->n_div[i] - 1) /
717 tctx->n_div[i];
718 rounded_down = (bit_size) / tctx->n_div[i];
719 num_rounded_down = rounded_up * tctx->n_div[i] - bit_size;
720 num_rounded_up = tctx->n_div[i] - num_rounded_down;
721 tctx->bits_main_spec[0][i][0] = (rounded_up + 1) / 2;
722 tctx->bits_main_spec[1][i][0] = rounded_up / 2;
723 tctx->bits_main_spec[0][i][1] = (rounded_down + 1) / 2;
724 tctx->bits_main_spec[1][i][1] = rounded_down / 2;
725 tctx->bits_main_spec_change[i] = num_rounded_up;
726
727 rounded_up = (vect_size + tctx->n_div[i] - 1) /
728 tctx->n_div[i];
729 rounded_down = (vect_size) / tctx->n_div[i];
730 num_rounded_down = rounded_up * tctx->n_div[i] - vect_size;
731 num_rounded_up = tctx->n_div[i] - num_rounded_down;
732 tctx->length[i][0] = rounded_up;
733 tctx->length[i][1] = rounded_down;
734 tctx->length_change[i] = num_rounded_up;
735 }
736
737 for (frametype = TWINVQ_FT_SHORT; frametype <= TWINVQ_FT_PPC; frametype++)
738 construct_perm_table(tctx, frametype);
739 }
740
ff_twinvq_decode_close(AVCodecContext * avctx)741 av_cold int ff_twinvq_decode_close(AVCodecContext *avctx)
742 {
743 TwinVQContext *tctx = avctx->priv_data;
744 int i;
745
746 for (i = 0; i < 3; i++) {
747 ff_mdct_end(&tctx->mdct_ctx[i]);
748 av_freep(&tctx->cos_tabs[i]);
749 }
750
751 av_freep(&tctx->curr_frame);
752 av_freep(&tctx->spectrum);
753 av_freep(&tctx->prev_frame);
754 av_freep(&tctx->tmp_buf);
755 av_freep(&tctx->fdsp);
756
757 return 0;
758 }
759
ff_twinvq_decode_init(AVCodecContext * avctx)760 av_cold int ff_twinvq_decode_init(AVCodecContext *avctx)
761 {
762 int ret;
763 TwinVQContext *tctx = avctx->priv_data;
764 int64_t frames_per_packet;
765
766 tctx->avctx = avctx;
767 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
768
769 if (!avctx->block_align) {
770 avctx->block_align = tctx->frame_size + 7 >> 3;
771 }
772 frames_per_packet = avctx->block_align * 8LL / tctx->frame_size;
773 if (frames_per_packet <= 0) {
774 av_log(avctx, AV_LOG_ERROR, "Block align is %"PRId64" bits, expected %d\n",
775 avctx->block_align * (int64_t)8, tctx->frame_size);
776 return AVERROR_INVALIDDATA;
777 }
778 if (frames_per_packet > TWINVQ_MAX_FRAMES_PER_PACKET) {
779 av_log(avctx, AV_LOG_ERROR, "Too many frames per packet (%"PRId64")\n",
780 frames_per_packet);
781 return AVERROR_INVALIDDATA;
782 }
783 tctx->frames_per_packet = frames_per_packet;
784
785 tctx->fdsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT);
786 if (!tctx->fdsp) {
787 ff_twinvq_decode_close(avctx);
788 return AVERROR(ENOMEM);
789 }
790 if ((ret = init_mdct_win(tctx))) {
791 av_log(avctx, AV_LOG_ERROR, "Error initializing MDCT\n");
792 ff_twinvq_decode_close(avctx);
793 return ret;
794 }
795 init_bitstream_params(tctx);
796
797 twinvq_memset_float(tctx->bark_hist[0][0], 0.1,
798 FF_ARRAY_ELEMS(tctx->bark_hist));
799
800 return 0;
801 }
802