1 /*
2 * ScreenPressor version 3 decoder
3 *
4 * Copyright (c) 2017 Paul B Mahol
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26
27 #include "libavutil/qsort.h"
28
29 #include "avcodec.h"
30 #include "bytestream.h"
31 #include "internal.h"
32 #include "scpr.h"
33
renew_table3(uint32_t nsym,uint32_t * cntsum,uint16_t * freqs,uint16_t * freqs1,uint16_t * cnts,uint8_t * dectab)34 static void renew_table3(uint32_t nsym, uint32_t *cntsum,
35 uint16_t *freqs, uint16_t *freqs1,
36 uint16_t *cnts, uint8_t *dectab)
37 {
38 uint32_t a = 0, b = 4096 / nsym, c = b - (b >> 1);
39
40 *cntsum = c * nsym;
41
42 for (int d = 0; d < nsym; d++) {
43 freqs[d] = b;
44 freqs1[d] = a;
45 cnts[d] = c;
46 for (int q = a + 128 - 1 >> 7, f = (a + b - 1 >> 7) + 1; q < f; q++)
47 dectab[q] = d;
48
49 a += b;
50 }
51 }
52
reinit_tables3(SCPRContext * s)53 static void reinit_tables3(SCPRContext * s)
54 {
55 for (int i = 0; i < 3; i++) {
56 for (int j = 0; j < 4096; j++) {
57 PixelModel3 *m = &s->pixel_model3[i][j];
58 m->type = 0;
59 }
60 }
61
62 for (int i = 0; i < 6; i++) {
63 renew_table3(256, &s->run_model3[i].cntsum,
64 s->run_model3[i].freqs[0], s->run_model3[i].freqs[1],
65 s->run_model3[i].cnts, s->run_model3[i].dectab);
66 }
67
68 renew_table3(256, &s->range_model3.cntsum,
69 s->range_model3.freqs[0], s->range_model3.freqs[1],
70 s->range_model3.cnts, s->range_model3.dectab);
71
72 renew_table3(5, &s->fill_model3.cntsum,
73 s->fill_model3.freqs[0], s->fill_model3.freqs[1],
74 s->fill_model3.cnts, s->fill_model3.dectab);
75
76 renew_table3(256, &s->count_model3.cntsum,
77 s->count_model3.freqs[0], s->count_model3.freqs[1],
78 s->count_model3.cnts, s->count_model3.dectab);
79
80 for (int i = 0; i < 4; i++) {
81 renew_table3(16, &s->sxy_model3[i].cntsum,
82 s->sxy_model3[i].freqs[0], s->sxy_model3[i].freqs[1],
83 s->sxy_model3[i].cnts, s->sxy_model3[i].dectab);
84 }
85
86 for (int i = 0; i < 2; i++) {
87 renew_table3(512, &s->mv_model3[i].cntsum,
88 s->mv_model3[i].freqs[0], s->mv_model3[i].freqs[1],
89 s->mv_model3[i].cnts, s->mv_model3[i].dectab);
90 }
91
92 for (int i = 0; i < 6; i++) {
93 renew_table3(6, &s->op_model3[i].cntsum,
94 s->op_model3[i].freqs[0], s->op_model3[i].freqs[1],
95 s->op_model3[i].cnts, s->op_model3[i].dectab);
96 }
97 }
98
decode3(GetByteContext * gb,RangeCoder * rc,uint32_t a,uint32_t b)99 static int decode3(GetByteContext *gb, RangeCoder *rc, uint32_t a, uint32_t b)
100 {
101 uint32_t code = a * (rc->code >> 12) + (rc->code & 0xFFF) - b;
102
103 while (code < 0x800000 && bytestream2_get_bytes_left(gb) > 0)
104 code = bytestream2_get_byteu(gb) | (code << 8);
105 rc->code = code;
106
107 return 0;
108 }
109
rescale(PixelModel3 * m,int * totfr)110 static void rescale(PixelModel3 *m, int *totfr)
111 {
112 uint32_t a;
113
114 a = 256 - m->size;
115 for (int b = 0; b < m->size; b++) {
116 m->freqs[b] -= m->freqs[b] >> 1;
117 a += m->freqs[b];
118 }
119
120 *totfr = a;
121 }
122
add_symbol(PixelModel3 * m,int index,uint32_t symbol,int * totfr,int max)123 static int add_symbol(PixelModel3 *m, int index, uint32_t symbol, int *totfr, int max)
124 {
125 if (m->size == max)
126 return 0;
127
128 for (int c = m->size - 1; c >= index; c--) {
129 m->symbols[c + 1] = m->symbols[c];
130 m->freqs[c + 1] = m->freqs[c];
131 }
132
133 m->symbols[index] = symbol;
134 m->freqs[index] = 50;
135 m->size++;
136
137 if (m->maxpos >= index)
138 m->maxpos++;
139
140 *totfr += 50;
141 if (*totfr + 50 > 4096)
142 rescale(m, totfr);
143
144 return 1;
145 }
146
decode_adaptive45(PixelModel3 * m,int rccode,uint32_t * value,uint16_t * a,uint16_t * b,uint32_t * c,int max)147 static int decode_adaptive45(PixelModel3 *m, int rccode, uint32_t *value,
148 uint16_t *a, uint16_t *b, uint32_t *c, int max)
149 {
150 uint32_t q, g, maxpos, d, e = *c, totfr = *c;
151 int ret;
152
153 for (d = 0; e <= 2048; d++)
154 e <<= 1;
155 maxpos = m->maxpos;
156 rccode >>= d;
157 *c = m->freqs[maxpos];
158 m->freqs[maxpos] += 4096 - e >> d;
159
160 for (q = 0, g = 0, e = 0; q < m->size; q++) {
161 uint32_t f = m->symbols[q];
162 uint32_t p = e + f - g;
163 uint32_t k = m->freqs[q];
164
165 if (rccode < p) {
166 *value = rccode - e + g;
167 *b = rccode << d;
168 *a = 1 << d;
169 m->freqs[maxpos] = *c;
170 ret = add_symbol(m, q, *value, &totfr, max);
171 *c = totfr;
172 return ret;
173 }
174
175 if (p + k > rccode) {
176 *value = f;
177 e += *value - g;
178 *b = e << d;
179 *a = k << d;
180 m->freqs[maxpos] = *c;
181 m->freqs[q] += 50;
182 totfr += 50;
183 if ((q != maxpos) && (m->freqs[q] > m->freqs[maxpos]))
184 m->maxpos = q;
185 if (totfr + 50 > 4096)
186 rescale(m, &totfr);
187 *c = totfr;
188 return 1;
189 }
190
191 e += f - g + k;
192 g = f + 1;
193 }
194
195 m->freqs[maxpos] = *c;
196 *value = g + rccode - e;
197 *b = rccode << d;
198 *a = 1 << d;
199 ret = add_symbol(m, q, *value, &totfr, max);
200 *c = totfr;
201 return ret;
202 }
203
update_model6_to_7(PixelModel3 * m)204 static int update_model6_to_7(PixelModel3 *m)
205 {
206 PixelModel3 n = {0};
207 int c, d, e, f, k, p, length, i, j, index;
208 uint16_t *freqs, *freqs1, *cnts;
209
210 n.type = 7;
211
212 length = m->length;
213 freqs = n.freqs;
214 freqs1 = n.freqs1;
215 cnts = n.cnts;
216 n.cntsum = m->cnts[length];
217 for (i = 0; i < length; i++) {
218 if (!m->cnts[i])
219 continue;
220 index = m->symbols[i];
221 freqs[index] = m->freqs[2 * i];
222 freqs1[index] = m->freqs[2 * i + 1];
223 cnts[index] = m->cnts[i];
224 }
225 c = 1 << m->fshift;
226 d = c - (c >> 1);
227 for (j = 0, e = 0; j < 256; j++) {
228 f = freqs[j];
229 if (!f) {
230 f = c;
231 freqs[j] = c;
232 freqs1[j] = e;
233 cnts[j] = d;
234 }
235 p = (e + 127) >> 7;
236 k = ((f + e - 1) >> 7) + 1;
237 if (k > FF_ARRAY_ELEMS(n.dectab))
238 return AVERROR_INVALIDDATA;
239 for (i = 0; i < k - p; i++)
240 n.dectab[p + i] = j;
241 e += f;
242 }
243
244 memcpy(m, &n, sizeof(n));
245
246 return 0;
247 }
248
calc_sum(PixelModel3 * m)249 static void calc_sum(PixelModel3 *m)
250 {
251 uint32_t a;
252 int len;
253
254 len = m->length;
255 a = 256 - m->size << (m->fshift > 0 ? m->fshift - 1 : 0);
256 for (int c = 0; c < len; c++)
257 a += m->cnts[c];
258 m->cnts[len] = a;
259 }
260
rescale_dec(PixelModel3 * m)261 static void rescale_dec(PixelModel3 *m)
262 {
263 uint16_t cnts[256] = {0};
264 uint16_t freqs[512] = {0};
265 int b, c, e, g;
266 uint32_t a;
267
268 for (a = 1 << (0 < m->fshift ? m->fshift - 1 : 0), b = 0; b < 256; b++)
269 cnts[b] = a;
270
271 for (a = 0, b = m->size; a < b; a++)
272 cnts[m->symbols[a]] = m->cnts[a];
273
274 for (b = a = 0; b < 256; b++) {
275 freqs[2 * b] = cnts[b];
276 freqs[2 * b + 1] = a;
277 a += cnts[b];
278 }
279
280 if (m->fshift > 0)
281 m->fshift--;
282
283 a = 256 - m->size << (0 < m->fshift ? m->fshift - 1 : 0);
284 for (b = 0, c = m->size; b < c; b++) {
285 m->cnts[b] -= m->cnts[b] >> 1;
286 a = a + m->cnts[b];
287 e = m->symbols[b];
288 g = freqs[2 * e + 1];
289 m->freqs[2 * b] = freqs[2 * e];
290 m->freqs[2 * b + 1] = g;
291 }
292 m->cnts[m->length] = a;
293 }
294
update_model5_to_6(PixelModel3 * m,uint8_t value)295 static int update_model5_to_6(PixelModel3 *m, uint8_t value)
296 {
297 PixelModel3 n = {0};
298 int c, d, e, f, g, k, q, p;
299
300 n.type = 6;
301 n.length = 32;
302
303 for (c = m->size, d = 256 - c, e = 0; e < c; e++)
304 d = d + m->freqs[e];
305
306 for (e = 0; d <= 2048; e++)
307 d <<= 1;
308
309 for (q = d = 0, g = q = 0; g < c; g++) {
310 p = m->symbols[g];
311 d = d + (p - q);
312 q = m->freqs[g];
313 k = q << e;
314 n.freqs[2 * g] = k;
315 n.freqs[2 * g + 1] = d << e;
316 n.cnts[g] = k - (k >> 1);
317 n.symbols[g] = p;
318 d += q;
319 q = p + 1;
320 }
321
322 n.fshift = e;
323 e = 1 << n.fshift;
324 d = 0;
325 if (value > 0) {
326 d = -1;
327 for (p = f = g = 0; p < c; p++) {
328 k = n.symbols[p];
329 if (k > d && k < value) {
330 d = k;
331 g = n.freqs[2 * p];
332 f = n.freqs[2 * p + 1];
333 }
334 }
335 d = 0 < g ? f + g + (value - d - 1 << n.fshift) : value << n.fshift;
336 }
337 n.freqs[2 * c] = e;
338 n.freqs[2 * c + 1] = d;
339 n.cnts[c] = e - (e >> 1);
340 n.symbols[c] = value;
341 n.size = c + 1;
342 e = 25 << n.fshift;
343 n.cnts[c] += e;
344 n.cnts[32] += e;
345 if (n.cnts[32] + e > 4096)
346 rescale_dec(&n);
347
348 calc_sum(&n);
349 for (c = 0, e = n.size - 1; c < e; c++) {
350 for (g = c + 1, f = n.size; g < f; g++) {
351 if (q = n.freqs[2 * g], k = n.freqs[2 * c], q > k) {
352 int l = n.freqs[2 * c + 1];
353 int h = n.freqs[2 * g + 1];
354 n.freqs[2 * c] = q;
355 n.freqs[2 * c + 1] = h;
356 n.freqs[2 * g] = k;
357 n.freqs[2 * g + 1] = l;
358 FFSWAP(uint16_t, n.cnts[c], n.cnts[g]);
359 FFSWAP(uint8_t, n.symbols[c], n.symbols[g]);
360 }
361 }
362 }
363
364 memcpy(m, &n, sizeof(n));
365
366 return 0;
367 }
368
grow_dec(PixelModel3 * m)369 static void grow_dec(PixelModel3 *m)
370 {
371 int a;
372
373 a = 2 * m->length;
374 m->cnts[2 * m->length] = m->cnts[m->length];
375 m->length = a;
376 }
377
add_dec(PixelModel3 * m,int sym,int f1,int f2)378 static int add_dec(PixelModel3 *m, int sym, int f1, int f2)
379 {
380 int size;
381
382 if (m->size >= 40 || m->size >= m->length)
383 return -1;
384
385 size = m->size;
386 m->symbols[size] = sym;
387 m->freqs[2 * size] = f1;
388 m->freqs[2 * size + 1] = f2;
389 m->cnts[size] = f1 - (f1 >> 1);
390 m->size++;
391
392 return size;
393 }
394
incr_cntdec(PixelModel3 * m,int a)395 static void incr_cntdec(PixelModel3 *m, int a)
396 {
397 int b, len, d, e, g;
398
399 b = 25 << m->fshift;
400 len = m->length;
401 m->cnts[a] += b;
402 m->cnts[len] += b;
403 if (a > 0 && m->cnts[a] > m->cnts[a - 1]) {
404 FFSWAP(uint16_t, m->cnts[a], m->cnts[a - 1]);
405 d = m->freqs[2 * a];
406 e = m->freqs[2 * a + 1];
407 g = m->freqs[2 * (a - 1) + 1];
408 m->freqs[2 * a] = m->freqs[2 * (a - 1)];
409 m->freqs[2 * a + 1] = g;
410 g = a - 1;
411 m->freqs[2 * g] = d;
412 m->freqs[2 * g + 1] = e;
413 FFSWAP(uint8_t, m->symbols[a], m->symbols[a - 1]);
414 }
415
416 if (m->cnts[len] + b > 4096)
417 rescale_dec(m);
418 }
419
decode_adaptive6(PixelModel3 * m,uint32_t code,uint32_t * value,uint16_t * a,uint16_t * b)420 static int decode_adaptive6(PixelModel3 *m, uint32_t code, uint32_t *value,
421 uint16_t *a, uint16_t *b)
422 {
423 int c, d, e, f, g, q;
424
425 for (c = 0, d = 0, e = 0, f = 0, g = 0, q = m->size; g < q; g++) {
426 uint32_t p = m->freqs[2 * g + 1];
427
428 if (p <= code) {
429 uint32_t k = m->freqs[2 * g];
430
431 if (p + k > code) {
432 *value = m->symbols[g];
433 *a = k;
434 *b = p;
435 incr_cntdec(m, g);
436 return 1;
437 }
438
439 if (p >= d) {
440 c = k;
441 d = p;
442 e = m->symbols[g];
443 }
444 }
445 }
446
447 g = 1 << m->fshift;
448 q = f = 0;
449
450 if (c > 0) {
451 f = code - (d + c) >> m->fshift;
452 q = f + e + 1;
453 f = d + c + (f << m->fshift);
454 } else {
455 q = code >> m->fshift;
456 f = q << m->fshift;
457 }
458
459 *a = g;
460 *b = f;
461 *value = q;
462
463 c = add_dec(m, q, g, f);
464 if (c < 0) {
465 if (m->length == 64)
466 return 0;
467 grow_dec(m);
468 c = add_dec(m, q, g, f);
469 }
470
471 incr_cntdec(m, c);
472 return 1;
473 }
474
cmpbytes(const void * p1,const void * p2)475 static int cmpbytes(const void *p1, const void *p2)
476 {
477 int left = *(const uint8_t *)p1;
478 int right = *(const uint8_t *)p2;
479 return FFDIFFSIGN(left, right);
480 }
481
update_model1_to_2(PixelModel3 * m,uint32_t val)482 static int update_model1_to_2(PixelModel3 *m, uint32_t val)
483 {
484 PixelModel3 n = {0};
485 int i, b;
486
487 n.type = 2;
488 n.size = m->size + 1;
489 b = m->size;
490 for (i = 0; i < b; i++)
491 n.symbols[i] = m->symbols[i];
492 n.symbols[b] = val;
493
494 memcpy(m, &n, sizeof(n));
495
496 return 0;
497 }
498
update_model1_to_4(PixelModel3 * m,uint32_t val)499 static int update_model1_to_4(PixelModel3 *m, uint32_t val)
500 {
501 PixelModel3 n = {0};
502 int size, i;
503
504 size = m->size;
505 n.type = 4;
506 n.size = size;
507 for (i = 0; i < n.size; i++) {
508 n.symbols[i] = m->symbols[i];
509 }
510 AV_QSORT(n.symbols, size, uint8_t, cmpbytes);
511 for (i = 0; i < n.size; i++) {
512 if (val == n.symbols[i]) {
513 n.freqs[i] = 100;
514 n.maxpos = i;
515 } else {
516 n.freqs[i] = 50;
517 }
518 }
519
520 memcpy(m, &n, sizeof(n));
521
522 return 0;
523 }
524
update_model1_to_5(PixelModel3 * m,uint32_t val)525 static int update_model1_to_5(PixelModel3 *m, uint32_t val)
526 {
527 int i, size, freqs;
528 uint32_t a;
529
530 update_model1_to_4(m, val);
531 size = m->size;
532 a = 256 - size;
533 for (i = 0; i < size; i++, a += freqs)
534 freqs = m->freqs[i];
535 m->type = 5;
536 m->cntsum = a;
537
538 return 0;
539 }
540
decode_static1(PixelModel3 * m,uint32_t val)541 static int decode_static1(PixelModel3 *m, uint32_t val)
542 {
543 uint32_t size;
544
545 size = m->size;
546 for (int i = 0; i < size; i++) {
547 if (val == m->symbols[i]) {
548 if (size <= 4)
549 return update_model1_to_4(m, val);
550 else
551 return update_model1_to_5(m, val);
552 }
553 }
554
555 if (size >= 14)
556 return update_model1_to_2(m, val);
557
558 m->symbols[size] = val;
559 m->size++;
560 return 0;
561 }
562
update_model2_to_6(PixelModel3 * m,uint8_t value,int a4)563 static int update_model2_to_6(PixelModel3 *m, uint8_t value, int a4)
564 {
565 PixelModel3 n = {0};
566 int c, d, e, f, g, q;
567
568 n.type = 6;
569 n.length = a4;
570
571 memset(n.symbols, 1u, a4);
572
573 c = m->size;
574 d = 256 - c + (64 * c + 64);
575 for (e = 0; d <= 2048; e++) {
576 d <<= 1;
577 }
578
579 g = q = 0;
580 AV_QSORT(m->symbols, c, uint8_t, cmpbytes);
581 for (f = d = 0; f < c; f++) {
582 int p = f;
583 int k = m->symbols[p];
584 int l;
585 g = g + (k - q);
586
587 if (k == value) {
588 d = p;
589 q = 128;
590 } else {
591 q = 64;
592 }
593 l = q << e;
594 n.freqs[2 * p] = l;
595 n.freqs[2 * p + 1] = g << e;
596 n.symbols[p] = k;
597 n.cnts[p] = l - (l >> 1);
598 g += q;
599 q = k + 1;
600 }
601 n.size = c;
602 n.fshift = e;
603 calc_sum(&n);
604
605 if (d > 0) {
606 c = n.freqs[0];
607 e = n.freqs[1];
608 g = n.freqs[2 * d + 1];
609 n.freqs[0] = n.freqs[2 * d];
610 n.freqs[1] = g;
611 n.freqs[2 * d] = c;
612 n.freqs[2 * d + 1] = e;
613 FFSWAP(uint16_t, n.cnts[0], n.cnts[d]);
614 FFSWAP(uint8_t, n.symbols[0], n.symbols[d]);
615 }
616
617 memcpy(m, &n, sizeof(n));
618
619 return 0;
620 }
621
update_model2_to_3(PixelModel3 * m,uint32_t val)622 static int update_model2_to_3(PixelModel3 *m, uint32_t val)
623 {
624 PixelModel3 n = {0};
625 uint32_t size;
626
627 n.type = 3;
628 n.size = m->size + 1;
629
630 size = m->size;
631 for (int i = 0; i < size; i++)
632 n.symbols[i] = m->symbols[i];
633 n.symbols[size] = val;
634
635 memcpy(m, &n, sizeof(n));
636
637 return 0;
638 }
639
decode_static2(PixelModel3 * m,uint32_t val)640 static int decode_static2(PixelModel3 *m, uint32_t val)
641 {
642 uint32_t size;
643
644 size = m->size;
645 for (int i = 0; i < size; i++) {
646 if (val == m->symbols[i]) {
647 int a;
648
649 if (m->size <= 32)
650 a = 32;
651 else
652 a = 64;
653 return update_model2_to_6(m, val, a);
654 }
655 }
656
657 if (size >= 64)
658 return update_model2_to_3(m, val);
659
660 m->symbols[size] = val;
661 m->size++;
662
663 return 0;
664 }
665
update_model3_to_7(PixelModel3 * m,uint8_t value)666 static int update_model3_to_7(PixelModel3 *m, uint8_t value)
667 {
668 PixelModel3 n = {0};
669 int c, d, e, f, g, q;
670
671 n.type = 7;
672
673 for (c = 0; c < 256; c++) {
674 d = c;
675 n.freqs[d] = 1;
676 n.cnts[d] = 1;
677 }
678
679 for (c = m->size, d = (4096 - (256 - c)) / (c + 1) | 0, e = d - (d >> 1), g = 0; g < c;) {
680 q = g++;
681 q = m->symbols[q];
682 n.freqs[q] = d;
683 n.cnts[q] = e;
684 }
685 n.freqs[value] += d;
686 n.cnts[value] += 16;
687 for (d = c = n.cntsum = 0; 256 > d; d++) {
688 e = d;
689 n.cntsum += n.cnts[e];
690 n.freqs1[e] = c;
691 g = n.freqs[e];
692 f = (c + g - 1 >> 7) + 1;
693 if (f > FF_ARRAY_ELEMS(n.dectab))
694 return AVERROR_INVALIDDATA;
695 for (q = c + 128 - 1 >> 7; q < f; q++) {
696 n.dectab[q] = e;
697 }
698 c += g;
699 }
700
701 memcpy(m, &n, sizeof(n));
702
703 return 0;
704 }
705
decode_static3(PixelModel3 * m,uint32_t val)706 static int decode_static3(PixelModel3 *m, uint32_t val)
707 {
708 uint32_t size = m->size;
709
710 for (int i = 0; i < size; i++) {
711 if (val == m->symbols[i])
712 return update_model3_to_7(m, val);
713 }
714
715 if (size >= 256)
716 return 0;
717
718 m->symbols[size] = val;
719 m->size++;
720 return 0;
721 }
722
sync_code3(GetByteContext * gb,RangeCoder * rc)723 static void sync_code3(GetByteContext *gb, RangeCoder *rc)
724 {
725 rc->code1++;
726 if (rc->code1 == 0x20000) {
727 rc->code = bytestream2_get_le32(gb);
728 rc->code1 = 0;
729 }
730 }
731
decode_value3(SCPRContext * s,uint32_t max,uint32_t * cntsum,uint16_t * freqs1,uint16_t * freqs2,uint16_t * cnts,uint8_t * dectable,uint32_t * value)732 static int decode_value3(SCPRContext *s, uint32_t max, uint32_t *cntsum,
733 uint16_t *freqs1, uint16_t *freqs2,
734 uint16_t *cnts, uint8_t *dectable,
735 uint32_t *value)
736 {
737 GetByteContext *gb = &s->gb;
738 RangeCoder *rc = &s->rc;
739 uint32_t r, y, a, b, e, g, q;
740
741 r = dectable[(rc->code & 0xFFFu) >> 7];
742 if (r < max) {
743 while (freqs2[r + 1] <= (rc->code & 0xFFF)) {
744 if (++r >= max)
745 break;
746 }
747 }
748
749 if (r > max)
750 return AVERROR_INVALIDDATA;
751
752 cnts[r] += 16;
753 a = freqs1[r];
754 b = freqs2[r];
755 *cntsum += 16;
756 if (*cntsum + 16 > 4096) {
757 *cntsum = 0;
758 for (int c = 0, i = 0; i < max + 1; i++) {
759 e = cnts[i];
760 freqs2[i] = c;
761 freqs1[i] = e;
762 g = (c + 127) >> 7;
763 c += e;
764 q = ((c - 1) >> 7) + 1;
765 if (q > g) {
766 for (int j = 0; j < q - g; j++)
767 dectable[j + g] = i;
768 }
769 y = e - (e >> 1);
770 cnts[i] = y;
771 *cntsum += y;
772 }
773 }
774
775 decode3(gb, rc, a, b);
776 sync_code3(gb, rc);
777
778 *value = r;
779
780 return 0;
781 }
782
calc_sum5(PixelModel3 * m)783 static void calc_sum5(PixelModel3 *m)
784 {
785 uint32_t a;
786
787 a = 256 - m->size;
788 for (int b = 0; b < m->size; b++)
789 a += m->freqs[b];
790 m->cntsum = a;
791 }
792
update_model4_to_5(PixelModel3 * m,uint32_t value)793 static int update_model4_to_5(PixelModel3 *m, uint32_t value)
794 {
795 PixelModel3 n = {0};
796 int c, e, g, totfr;
797
798 n.type = 5;
799
800 for (c = 0, e = 0; c < m->size && m->symbols[c] < value; c++) {
801 n.symbols[c] = m->symbols[c];
802 e += n.freqs[c] = m->freqs[c];
803 }
804
805 g = c;
806 n.symbols[g] = value;
807 e += n.freqs[g++] = 50;
808 for (; c < m->size; g++, c++) {
809 n.symbols[g] = m->symbols[c];
810 e += n.freqs[g] = m->freqs[c];
811 }
812 n.size = m->size + 1;
813 if (e > 4096)
814 rescale(&n, &totfr);
815
816 calc_sum5(&n);
817
818 memcpy(m, &n, sizeof(n));
819
820 return 0;
821 }
822
decode_unit3(SCPRContext * s,PixelModel3 * m,uint32_t code,uint32_t * value)823 static int decode_unit3(SCPRContext *s, PixelModel3 *m, uint32_t code, uint32_t *value)
824 {
825 GetByteContext *gb = &s->gb;
826 RangeCoder *rc = &s->rc;
827 uint16_t a = 0, b = 0;
828 uint32_t param;
829 int type;
830 int ret;
831
832 type = m->type;
833 switch (type) {
834 case 0:
835 *value = bytestream2_get_byte(&s->gb);
836 m->type = 1;
837 m->size = 1;
838 m->symbols[0] = *value;
839 sync_code3(gb, rc);
840 break;
841 case 1:
842 *value = bytestream2_get_byte(&s->gb);
843 decode_static1(m, *value);
844 sync_code3(gb, rc);
845 break;
846 case 2:
847 *value = bytestream2_get_byte(&s->gb);
848 decode_static2(m, *value);
849 sync_code3(gb, rc);
850 break;
851 case 3:
852 *value = bytestream2_get_byte(&s->gb);
853 ret = decode_static3(m, *value);
854 if (ret < 0)
855 return AVERROR_INVALIDDATA;
856 sync_code3(gb, rc);
857 break;
858 case 4:
859 param = m->freqs[0] + m->freqs[1] + m->freqs[2] + m->freqs[3] + 256 - m->size;
860 if (!decode_adaptive45(m, code, value, &a, &b, ¶m, 4))
861 update_model4_to_5(m, *value);
862 decode3(gb, rc, a, b);
863 sync_code3(gb, rc);
864 break;
865 case 5:
866 if (!decode_adaptive45(m, code, value, &a, &b, &m->cntsum, 16))
867 update_model5_to_6(m, *value);
868 decode3(gb, rc, a, b);
869 sync_code3(gb, rc);
870 break;
871 case 6:
872 if (!decode_adaptive6(m, code, value, &a, &b)) {
873 ret = update_model6_to_7(m);
874 if (ret < 0)
875 return AVERROR_INVALIDDATA;
876 }
877 decode3(gb, rc, a, b);
878 sync_code3(gb, rc);
879 break;
880 case 7:
881 return decode_value3(s, 255, &m->cntsum,
882 m->freqs, m->freqs1,
883 m->cnts, m->dectab, value);
884 }
885
886 if (*value > 255)
887 return AVERROR_INVALIDDATA;
888
889 return 0;
890 }
891
decode_units3(SCPRContext * s,uint32_t * red,uint32_t * green,uint32_t * blue,int * cx,int * cx1)892 static int decode_units3(SCPRContext * s, uint32_t *red,
893 uint32_t *green, uint32_t *blue,
894 int *cx, int *cx1)
895 {
896 RangeCoder *rc = &s->rc;
897 int ret;
898
899 ret = decode_unit3(s, &s->pixel_model3[0][*cx + *cx1], rc->code & 0xFFF, red);
900 if (ret < 0)
901 return ret;
902
903 *cx1 = (*cx << 6) & 0xFC0;
904 *cx = *red >> 2;
905
906 ret = decode_unit3(s, &s->pixel_model3[1][*cx + *cx1], rc->code & 0xFFF, green);
907 if (ret < 0)
908 return ret;
909
910 *cx1 = (*cx << 6) & 0xFC0;
911 *cx = *green >> 2;
912
913 ret = decode_unit3(s, &s->pixel_model3[2][*cx + *cx1], rc->code & 0xFFF, blue);
914 if (ret < 0)
915 return ret;
916
917 *cx1 = (*cx << 6) & 0xFC0;
918 *cx = *blue >> 2;
919
920 return 0;
921 }
922
init_rangecoder3(RangeCoder * rc,GetByteContext * gb)923 static void init_rangecoder3(RangeCoder *rc, GetByteContext *gb)
924 {
925 rc->code = bytestream2_get_le32(gb);
926 rc->code1 = 0;
927 }
928
decompress_i3(AVCodecContext * avctx,uint32_t * dst,int linesize)929 static int decompress_i3(AVCodecContext *avctx, uint32_t *dst, int linesize)
930 {
931 SCPRContext *s = avctx->priv_data;
932 GetByteContext *gb = &s->gb;
933 RangeCoder *rc = &s->rc;
934 int cx = 0, cx1 = 0, k = 0;
935 int run, off, y = 0, x = 0, ret;
936 uint32_t backstep = linesize - avctx->width;
937 uint32_t clr = 0, lx, ly, ptype, r, g, b;
938
939 bytestream2_skip(gb, 1);
940 init_rangecoder3(rc, gb);
941 reinit_tables3(s);
942
943 while (k < avctx->width + 1) {
944 ret = decode_units3(s, &r, &g, &b, &cx, &cx1);
945 if (ret < 0)
946 return ret;
947 ret = decode_value3(s, 255, &s->run_model3[0].cntsum,
948 s->run_model3[0].freqs[0],
949 s->run_model3[0].freqs[1],
950 s->run_model3[0].cnts,
951 s->run_model3[0].dectab, &run);
952 if (ret < 0)
953 return ret;
954 if (run <= 0)
955 return AVERROR_INVALIDDATA;
956
957 clr = (b << 16) + (g << 8) + r;
958 k += run;
959 while (run-- > 0) {
960 if (y >= avctx->height)
961 return AVERROR_INVALIDDATA;
962
963 dst[y * linesize + x] = clr;
964 lx = x;
965 ly = y;
966 x++;
967 if (x >= avctx->width) {
968 x = 0;
969 y++;
970 }
971 }
972 }
973 off = -linesize - 1;
974 ptype = 0;
975
976 while (x < avctx->width && y < avctx->height) {
977 ret = decode_value3(s, 5, &s->op_model3[ptype].cntsum,
978 s->op_model3[ptype].freqs[0],
979 s->op_model3[ptype].freqs[1],
980 s->op_model3[ptype].cnts,
981 s->op_model3[ptype].dectab, &ptype);
982 if (ret < 0)
983 return ret;
984 if (ptype == 0) {
985 ret = decode_units3(s, &r, &g, &b, &cx, &cx1);
986 if (ret < 0)
987 return ret;
988 clr = (b << 16) + (g << 8) + r;
989 }
990 if (ptype > 5)
991 return AVERROR_INVALIDDATA;
992 ret = decode_value3(s, 255, &s->run_model3[ptype].cntsum,
993 s->run_model3[ptype].freqs[0],
994 s->run_model3[ptype].freqs[1],
995 s->run_model3[ptype].cnts,
996 s->run_model3[ptype].dectab, &run);
997 if (ret < 0)
998 return ret;
999 if (run <= 0)
1000 return AVERROR_INVALIDDATA;
1001
1002 ret = decode_run_i(avctx, ptype, run, &x, &y, clr,
1003 dst, linesize, &lx, &ly,
1004 backstep, off, &cx, &cx1);
1005 if (ret < 0)
1006 return ret;
1007 }
1008
1009 return 0;
1010 }
1011
decompress_p3(AVCodecContext * avctx,uint32_t * dst,int linesize,uint32_t * prev,int plinesize)1012 static int decompress_p3(AVCodecContext *avctx,
1013 uint32_t *dst, int linesize,
1014 uint32_t *prev, int plinesize)
1015 {
1016 SCPRContext *s = avctx->priv_data;
1017 GetByteContext *gb = &s->gb;
1018 int ret, temp, min, max, x, y, cx = 0, cx1 = 0;
1019 int backstep = linesize - avctx->width;
1020 int mvx = 0, mvy = 0;
1021
1022 if (bytestream2_get_byte(gb) == 0)
1023 return 1;
1024 init_rangecoder3(&s->rc, gb);
1025
1026 ret = decode_value3(s, 255, &s->range_model3.cntsum,
1027 s->range_model3.freqs[0],
1028 s->range_model3.freqs[1],
1029 s->range_model3.cnts,
1030 s->range_model3.dectab, &min);
1031 ret |= decode_value3(s, 255, &s->range_model3.cntsum,
1032 s->range_model3.freqs[0],
1033 s->range_model3.freqs[1],
1034 s->range_model3.cnts,
1035 s->range_model3.dectab, &temp);
1036 if (ret < 0)
1037 return ret;
1038
1039 min += temp << 8;
1040 ret |= decode_value3(s, 255, &s->range_model3.cntsum,
1041 s->range_model3.freqs[0],
1042 s->range_model3.freqs[1],
1043 s->range_model3.cnts,
1044 s->range_model3.dectab, &max);
1045 ret |= decode_value3(s, 255, &s->range_model3.cntsum,
1046 s->range_model3.freqs[0],
1047 s->range_model3.freqs[1],
1048 s->range_model3.cnts,
1049 s->range_model3.dectab, &temp);
1050 if (ret < 0)
1051 return ret;
1052
1053 max += temp << 8;
1054 if (min > max || min >= s->nbcount)
1055 return AVERROR_INVALIDDATA;
1056
1057 memset(s->blocks, 0, sizeof(*s->blocks) * s->nbcount);
1058
1059 while (min <= max) {
1060 int fill, count;
1061
1062 ret = decode_value3(s, 4, &s->fill_model3.cntsum,
1063 s->fill_model3.freqs[0],
1064 s->fill_model3.freqs[1],
1065 s->fill_model3.cnts,
1066 s->fill_model3.dectab, &fill);
1067 ret |= decode_value3(s, 255, &s->count_model3.cntsum,
1068 s->count_model3.freqs[0],
1069 s->count_model3.freqs[1],
1070 s->count_model3.cnts,
1071 s->count_model3.dectab, &count);
1072 if (ret < 0)
1073 return ret;
1074 if (count <= 0)
1075 return AVERROR_INVALIDDATA;
1076
1077 while (min < s->nbcount && count-- > 0) {
1078 s->blocks[min++] = fill;
1079 }
1080 }
1081
1082 ret = av_frame_copy(s->current_frame, s->last_frame);
1083 if (ret < 0)
1084 return ret;
1085
1086 for (y = 0; y < s->nby; y++) {
1087 for (x = 0; x < s->nbx; x++) {
1088 int sy1 = 0, sy2 = 16, sx1 = 0, sx2 = 16;
1089
1090 if (s->blocks[y * s->nbx + x] == 0)
1091 continue;
1092
1093 if (((s->blocks[y * s->nbx + x] + 1) & 1) > 0) {
1094 ret = decode_value3(s, 15, &s->sxy_model3[0].cntsum,
1095 s->sxy_model3[0].freqs[0],
1096 s->sxy_model3[0].freqs[1],
1097 s->sxy_model3[0].cnts,
1098 s->sxy_model3[0].dectab, &sx1);
1099 ret |= decode_value3(s, 15, &s->sxy_model3[1].cntsum,
1100 s->sxy_model3[1].freqs[0],
1101 s->sxy_model3[1].freqs[1],
1102 s->sxy_model3[1].cnts,
1103 s->sxy_model3[1].dectab, &sy1);
1104 ret |= decode_value3(s, 15, &s->sxy_model3[2].cntsum,
1105 s->sxy_model3[2].freqs[0],
1106 s->sxy_model3[2].freqs[1],
1107 s->sxy_model3[2].cnts,
1108 s->sxy_model3[2].dectab, &sx2);
1109 ret |= decode_value3(s, 15, &s->sxy_model3[3].cntsum,
1110 s->sxy_model3[3].freqs[0],
1111 s->sxy_model3[3].freqs[1],
1112 s->sxy_model3[3].cnts,
1113 s->sxy_model3[3].dectab, &sy2);
1114 if (ret < 0)
1115 return ret;
1116
1117 sx2++;
1118 sy2++;
1119 }
1120 if (((s->blocks[y * s->nbx + x] + 3) & 2) > 0) {
1121 int i, a, b, c, j, by = y * 16, bx = x * 16;
1122 uint32_t code;
1123
1124 a = s->rc.code & 0xFFF;
1125 c = 1;
1126
1127 if (a < 0x800)
1128 c = 0;
1129 b = 2048;
1130 if (!c)
1131 b = 0;
1132
1133 code = a + ((s->rc.code >> 1) & 0xFFFFF800) - b;
1134 while (code < 0x800000 && bytestream2_get_bytes_left(gb) > 0)
1135 code = bytestream2_get_byteu(gb) | (code << 8);
1136 s->rc.code = code;
1137
1138 sync_code3(gb, &s->rc);
1139
1140 if (!c) {
1141 ret = decode_value3(s, 511, &s->mv_model3[0].cntsum,
1142 s->mv_model3[0].freqs[0],
1143 s->mv_model3[0].freqs[1],
1144 s->mv_model3[0].cnts,
1145 s->mv_model3[0].dectab, &mvx);
1146 ret |= decode_value3(s, 511, &s->mv_model3[1].cntsum,
1147 s->mv_model3[1].freqs[0],
1148 s->mv_model3[1].freqs[1],
1149 s->mv_model3[1].cnts,
1150 s->mv_model3[1].dectab, &mvy);
1151 if (ret < 0)
1152 return ret;
1153
1154 mvx -= 256;
1155 mvy -= 256;
1156 }
1157
1158 if (by + mvy + sy1 < 0 || bx + mvx + sx1 < 0 ||
1159 by + mvy + sy1 >= avctx->height || bx + mvx + sx1 >= avctx->width)
1160 return AVERROR_INVALIDDATA;
1161
1162 for (i = 0; i < sy2 - sy1 && (by + sy1 + i) < avctx->height && (by + mvy + sy1 + i) < avctx->height; i++) {
1163 for (j = 0; j < sx2 - sx1 && (bx + sx1 + j) < avctx->width && (bx + mvx + sx1 + j) < avctx->width; j++) {
1164 dst[(by + i + sy1) * linesize + bx + sx1 + j] = prev[(by + mvy + sy1 + i) * plinesize + bx + sx1 + mvx + j];
1165 }
1166 }
1167 } else {
1168 int run, bx = x * 16 + sx1, by = y * 16 + sy1;
1169 uint32_t clr, ptype = 0, r, g, b;
1170
1171 if (bx >= avctx->width)
1172 return AVERROR_INVALIDDATA;
1173
1174 for (; by < y * 16 + sy2 && by < avctx->height;) {
1175 ret = decode_value3(s, 5, &s->op_model3[ptype].cntsum,
1176 s->op_model3[ptype].freqs[0],
1177 s->op_model3[ptype].freqs[1],
1178 s->op_model3[ptype].cnts,
1179 s->op_model3[ptype].dectab, &ptype);
1180 if (ret < 0)
1181 return ret;
1182 if (ptype == 0) {
1183 ret = decode_units3(s, &r, &g, &b, &cx, &cx1);
1184 if (ret < 0)
1185 return ret;
1186
1187 clr = (b << 16) + (g << 8) + r;
1188 }
1189 if (ptype > 5)
1190 return AVERROR_INVALIDDATA;
1191 ret = decode_value3(s, 255, &s->run_model3[ptype].cntsum,
1192 s->run_model3[ptype].freqs[0],
1193 s->run_model3[ptype].freqs[1],
1194 s->run_model3[ptype].cnts,
1195 s->run_model3[ptype].dectab, &run);
1196 if (ret < 0)
1197 return ret;
1198 if (run <= 0)
1199 return AVERROR_INVALIDDATA;
1200
1201 ret = decode_run_p(avctx, ptype, run, x, y, clr,
1202 dst, prev, linesize, plinesize, &bx, &by,
1203 backstep, sx1, sx2, &cx, &cx1);
1204 if (ret < 0)
1205 return ret;
1206 }
1207 }
1208 }
1209 }
1210
1211 return 0;
1212 }
1213