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path: root/libavcodec/scpr.c (plain)
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1/*
2 * ScreenPressor 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 "avcodec.h"
28#include "bytestream.h"
29#include "internal.h"
30
31#define TOP 0x01000000
32#define BOT 0x010000
33
34typedef struct RangeCoder {
35 unsigned code;
36 unsigned range;
37 unsigned code1;
38} RangeCoder;
39
40typedef struct PixelModel {
41 unsigned freq[256];
42 unsigned lookup[16];
43 unsigned total_freq;
44} PixelModel;
45
46typedef struct SCPRContext {
47 AVFrame *last_frame;
48 AVFrame *current_frame;
49 GetByteContext gb;
50 RangeCoder rc;
51 PixelModel pixel_model[3][4096];
52 unsigned op_model[6][7];
53 unsigned run_model[6][257];
54 unsigned range_model[257];
55 unsigned count_model[257];
56 unsigned fill_model[6];
57 unsigned sxy_model[4][17];
58 unsigned mv_model[2][513];
59 unsigned nbx, nby;
60 unsigned nbcount;
61 unsigned *blocks;
62 unsigned cbits;
63 int cxshift;
64
65 int (*get_freq)(RangeCoder *rc, unsigned total_freq, unsigned *freq);
66 int (*decode)(GetByteContext *gb, RangeCoder *rc, unsigned cumFreq, unsigned freq, unsigned total_freq);
67} SCPRContext;
68
69static void init_rangecoder(RangeCoder *rc, GetByteContext *gb)
70{
71 rc->code1 = 0;
72 rc->range = 0xFFFFFFFFU;
73 rc->code = bytestream2_get_be32(gb);
74}
75
76static void reinit_tables(SCPRContext *s)
77{
78 int comp, i, j;
79
80 for (comp = 0; comp < 3; comp++) {
81 for (j = 0; j < 4096; j++) {
82 if (s->pixel_model[comp][j].total_freq != 256) {
83 for (i = 0; i < 256; i++)
84 s->pixel_model[comp][j].freq[i] = 1;
85 for (i = 0; i < 16; i++)
86 s->pixel_model[comp][j].lookup[i] = 16;
87 s->pixel_model[comp][j].total_freq = 256;
88 }
89 }
90 }
91
92 for (j = 0; j < 6; j++) {
93 unsigned *p = s->run_model[j];
94 for (i = 0; i < 256; i++)
95 p[i] = 1;
96 p[256] = 256;
97 }
98
99 for (j = 0; j < 6; j++) {
100 unsigned *op = s->op_model[j];
101 for (i = 0; i < 6; i++)
102 op[i] = 1;
103 op[6] = 6;
104 }
105
106 for (i = 0; i < 256; i++) {
107 s->range_model[i] = 1;
108 s->count_model[i] = 1;
109 }
110 s->range_model[256] = 256;
111 s->count_model[256] = 256;
112
113 for (i = 0; i < 5; i++) {
114 s->fill_model[i] = 1;
115 }
116 s->fill_model[5] = 5;
117
118 for (j = 0; j < 4; j++) {
119 for (i = 0; i < 16; i++) {
120 s->sxy_model[j][i] = 1;
121 }
122 s->sxy_model[j][16] = 16;
123 }
124
125 for (i = 0; i < 512; i++) {
126 s->mv_model[0][i] = 1;
127 s->mv_model[1][i] = 1;
128 }
129 s->mv_model[0][512] = 512;
130 s->mv_model[1][512] = 512;
131}
132
133static int decode(GetByteContext *gb, RangeCoder *rc, unsigned cumFreq, unsigned freq, unsigned total_freq)
134{
135 rc->code -= cumFreq * rc->range;
136 rc->range *= freq;
137
138 while (rc->range < TOP && bytestream2_get_bytes_left(gb) > 0) {
139 unsigned byte = bytestream2_get_byte(gb);
140 rc->code = (rc->code << 8) | byte;
141 rc->range <<= 8;
142 }
143
144 return 0;
145}
146
147static int get_freq(RangeCoder *rc, unsigned total_freq, unsigned *freq)
148{
149 if (total_freq == 0)
150 return AVERROR_INVALIDDATA;
151
152 rc->range = rc->range / total_freq;
153
154 if (rc->range == 0)
155 return AVERROR_INVALIDDATA;
156
157 *freq = rc->code / rc->range;
158
159 return 0;
160}
161
162static int decode0(GetByteContext *gb, RangeCoder *rc, unsigned cumFreq, unsigned freq, unsigned total_freq)
163{
164 int t;
165
166 if (total_freq == 0)
167 return AVERROR_INVALIDDATA;
168
169 t = rc->range * (uint64_t)cumFreq / total_freq;
170
171 rc->code1 += t + 1;
172 rc->range = rc->range * (uint64_t)(freq + cumFreq) / total_freq - (t + 1);
173
174 while (rc->range < TOP && bytestream2_get_bytes_left(gb) > 0) {
175 unsigned byte = bytestream2_get_byte(gb);
176 rc->code = (rc->code << 8) | byte;
177 rc->code1 <<= 8;
178 rc->range <<= 8;
179 }
180
181 return 0;
182}
183
184static int get_freq0(RangeCoder *rc, unsigned total_freq, unsigned *freq)
185{
186 if (rc->range == 0)
187 return AVERROR_INVALIDDATA;
188
189 *freq = total_freq * (uint64_t)(rc->code - rc->code1) / rc->range;
190
191 return 0;
192}
193
194static int decode_value(SCPRContext *s, unsigned *cnt, unsigned maxc, unsigned step, unsigned *rval)
195{
196 GetByteContext *gb = &s->gb;
197 RangeCoder *rc = &s->rc;
198 unsigned totfr = cnt[maxc];
199 unsigned value;
200 unsigned c = 0, cumfr = 0, cnt_c = 0;
201 int i, ret;
202
203 if ((ret = s->get_freq(rc, totfr, &value)) < 0)
204 return ret;
205
206 while (c < maxc) {
207 cnt_c = cnt[c];
208 if (value >= cumfr + cnt_c)
209 cumfr += cnt_c;
210 else
211 break;
212 c++;
213 }
214 if ((ret = s->decode(gb, rc, cumfr, cnt_c, totfr)) < 0)
215 return ret;
216
217 cnt[c] = cnt_c + step;
218 totfr += step;
219 if (totfr > BOT) {
220 totfr = 0;
221 for (i = 0; i < maxc; i++) {
222 unsigned nc = (cnt[i] >> 1) + 1;
223 cnt[i] = nc;
224 totfr += nc;
225 }
226 }
227
228 cnt[maxc] = totfr;
229 *rval = c;
230
231 return 0;
232}
233
234static int decode_unit(SCPRContext *s, PixelModel *pixel, unsigned step, unsigned *rval)
235{
236 GetByteContext *gb = &s->gb;
237 RangeCoder *rc = &s->rc;
238 unsigned totfr = pixel->total_freq;
239 unsigned value, x = 0, cumfr = 0, cnt_x = 0;
240 int i, j, ret, c, cnt_c;
241
242 if ((ret = s->get_freq(rc, totfr, &value)) < 0)
243 return ret;
244
245 while (x < 16) {
246 cnt_x = pixel->lookup[x];
247 if (value >= cumfr + cnt_x)
248 cumfr += cnt_x;
249 else
250 break;
251 x++;
252 }
253
254 c = x * 16;
255 cnt_c = 0;
256 while (c < 256) {
257 cnt_c = pixel->freq[c];
258 if (value >= cumfr + cnt_c)
259 cumfr += cnt_c;
260 else
261 break;
262 c++;
263 }
264
265 if ((ret = s->decode(gb, rc, cumfr, cnt_c, totfr)) < 0)
266 return ret;
267
268 pixel->freq[c] = cnt_c + step;
269 pixel->lookup[x] = cnt_x + step;
270 totfr += step;
271 if (totfr > BOT) {
272 totfr = 0;
273 for (i = 0; i < 256; i++) {
274 unsigned nc = (pixel->freq[i] >> 1) + 1;
275 pixel->freq[i] = nc;
276 totfr += nc;
277 }
278 for (i = 0; i < 16; i++) {
279 unsigned sum = 0;
280 unsigned i16_17 = i << 4;
281 for (j = 0; j < 16; j++)
282 sum += pixel->freq[i16_17 + j];
283 pixel->lookup[i] = sum;
284 }
285 }
286 pixel->total_freq = totfr;
287
288 *rval = c & s->cbits;
289
290 return 0;
291}
292
293static int decompress_i(AVCodecContext *avctx, uint32_t *dst, int linesize)
294{
295 SCPRContext *s = avctx->priv_data;
296 GetByteContext *gb = &s->gb;
297 int cx = 0, cx1 = 0, k = 0, clr = 0;
298 int run, r, g, b, off, y = 0, x = 0, z, ret;
299 unsigned backstep = linesize - avctx->width;
300 const int cxshift = s->cxshift;
301 unsigned lx, ly, ptype;
302
303 reinit_tables(s);
304 bytestream2_skip(gb, 2);
305 init_rangecoder(&s->rc, gb);
306
307 while (k < avctx->width + 1) {
308 ret = decode_unit(s, &s->pixel_model[0][cx + cx1], 400, &r);
309 if (ret < 0)
310 return ret;
311
312 cx1 = (cx << 6) & 0xFC0;
313 cx = r >> cxshift;
314 ret = decode_unit(s, &s->pixel_model[1][cx + cx1], 400, &g);
315 if (ret < 0)
316 return ret;
317
318 cx1 = (cx << 6) & 0xFC0;
319 cx = g >> cxshift;
320 ret = decode_unit(s, &s->pixel_model[2][cx + cx1], 400, &b);
321 if (ret < 0)
322 return ret;
323
324 cx1 = (cx << 6) & 0xFC0;
325 cx = b >> cxshift;
326
327 ret = decode_value(s, s->run_model[0], 256, 400, &run);
328 if (ret < 0)
329 return ret;
330
331 clr = (b << 16) + (g << 8) + r;
332 k += run;
333 while (run-- > 0) {
334 dst[y * linesize + x] = clr;
335 lx = x;
336 ly = y;
337 x++;
338 if (x >= avctx->width) {
339 x = 0;
340 y++;
341 }
342 }
343 }
344 off = -linesize - 1;
345 ptype = 0;
346
347 while (x < avctx->width && y < avctx->height) {
348 ret = decode_value(s, s->op_model[ptype], 6, 1000, &ptype);
349 if (ret < 0)
350 return ret;
351 if (ptype == 0) {
352 ret = decode_unit(s, &s->pixel_model[0][cx + cx1], 400, &r);
353 if (ret < 0)
354 return ret;
355
356 cx1 = (cx << 6) & 0xFC0;
357 cx = r >> cxshift;
358 ret = decode_unit(s, &s->pixel_model[1][cx + cx1], 400, &g);
359 if (ret < 0)
360 return ret;
361
362 cx1 = (cx << 6) & 0xFC0;
363 cx = g >> cxshift;
364 ret = decode_unit(s, &s->pixel_model[2][cx + cx1], 400, &b);
365 if (ret < 0)
366 return ret;
367
368 clr = (b << 16) + (g << 8) + r;
369 }
370 if (ptype > 5)
371 return AVERROR_INVALIDDATA;
372 ret = decode_value(s, s->run_model[ptype], 256, 400, &run);
373 if (ret < 0)
374 return ret;
375
376 switch (ptype) {
377 case 0:
378 while (run-- > 0) {
379 if (y >= avctx->height)
380 return AVERROR_INVALIDDATA;
381
382 dst[y * linesize + x] = clr;
383 lx = x;
384 ly = y;
385 x++;
386 if (x >= avctx->width) {
387 x = 0;
388 y++;
389 }
390 }
391 break;
392 case 1:
393 while (run-- > 0) {
394 if (y >= avctx->height)
395 return AVERROR_INVALIDDATA;
396
397 dst[y * linesize + x] = dst[ly * linesize + lx];
398 lx = x;
399 ly = y;
400 x++;
401 if (x >= avctx->width) {
402 x = 0;
403 y++;
404 }
405 }
406 clr = dst[ly * linesize + lx];
407 break;
408 case 2:
409 while (run-- > 0) {
410 if (y < 1 || y >= avctx->height)
411 return AVERROR_INVALIDDATA;
412
413 clr = dst[y * linesize + x + off + 1];
414 dst[y * linesize + x] = clr;
415 lx = x;
416 ly = y;
417 x++;
418 if (x >= avctx->width) {
419 x = 0;
420 y++;
421 }
422 }
423 break;
424 case 4:
425 while (run-- > 0) {
426 uint8_t *odst = (uint8_t *)dst;
427
428 if (y < 1 || y >= avctx->height ||
429 (y == 1 && x == 0))
430 return AVERROR_INVALIDDATA;
431
432 if (x == 0) {
433 z = backstep;
434 } else {
435 z = 0;
436 }
437
438 r = odst[(ly * linesize + lx) * 4] +
439 odst[((y * linesize + x) + off - z) * 4 + 4] -
440 odst[((y * linesize + x) + off - z) * 4];
441 g = odst[(ly * linesize + lx) * 4 + 1] +
442 odst[((y * linesize + x) + off - z) * 4 + 5] -
443 odst[((y * linesize + x) + off - z) * 4 + 1];
444 b = odst[(ly * linesize + lx) * 4 + 2] +
445 odst[((y * linesize + x) + off - z) * 4 + 6] -
446 odst[((y * linesize + x) + off - z) * 4 + 2];
447 clr = ((b & 0xFF) << 16) + ((g & 0xFF) << 8) + (r & 0xFF);
448 dst[y * linesize + x] = clr;
449 lx = x;
450 ly = y;
451 x++;
452 if (x >= avctx->width) {
453 x = 0;
454 y++;
455 }
456 }
457 break;
458 case 5:
459 while (run-- > 0) {
460 if (y < 1 || y >= avctx->height ||
461 (y == 1 && x == 0))
462 return AVERROR_INVALIDDATA;
463
464 if (x == 0) {
465 z = backstep;
466 } else {
467 z = 0;
468 }
469
470 clr = dst[y * linesize + x + off - z];
471 dst[y * linesize + x] = clr;
472 lx = x;
473 ly = y;
474 x++;
475 if (x >= avctx->width) {
476 x = 0;
477 y++;
478 }
479 }
480 break;
481 }
482
483 if (avctx->bits_per_coded_sample == 16) {
484 cx1 = (clr & 0x3F00) >> 2;
485 cx = (clr & 0xFFFFFF) >> 16;
486 } else {
487 cx1 = (clr & 0xFC00) >> 4;
488 cx = (clr & 0xFFFFFF) >> 18;
489 }
490 }
491
492 return 0;
493}
494
495static int decompress_p(AVCodecContext *avctx,
496 uint32_t *dst, int linesize,
497 uint32_t *prev, int plinesize)
498{
499 SCPRContext *s = avctx->priv_data;
500 GetByteContext *gb = &s->gb;
501 int ret, temp, min, max, x, y, cx = 0, cx1 = 0;
502 int backstep = linesize - avctx->width;
503 const int cxshift = s->cxshift;
504
505 if (bytestream2_get_byte(gb) == 0)
506 return 0;
507 bytestream2_skip(gb, 1);
508 init_rangecoder(&s->rc, gb);
509
510 ret = decode_value(s, s->range_model, 256, 1, &min);
511 ret |= decode_value(s, s->range_model, 256, 1, &temp);
512 min += temp << 8;
513 ret |= decode_value(s, s->range_model, 256, 1, &max);
514 ret |= decode_value(s, s->range_model, 256, 1, &temp);
515 if (ret < 0)
516 return ret;
517
518 max += temp << 8;
519 memset(s->blocks, 0, sizeof(*s->blocks) * s->nbcount);
520
521 while (min <= max) {
522 int fill, count;
523
524 ret = decode_value(s, s->fill_model, 5, 10, &fill);
525 ret |= decode_value(s, s->count_model, 256, 20, &count);
526 if (ret < 0)
527 return ret;
528
529 while (min < s->nbcount && count-- > 0) {
530 s->blocks[min++] = fill;
531 }
532 }
533
534 for (y = 0; y < s->nby; y++) {
535 for (x = 0; x < s->nbx; x++) {
536 int sy1 = 0, sy2 = 16, sx1 = 0, sx2 = 16;
537
538 if (s->blocks[y * s->nbx + x] == 0)
539 continue;
540
541 if (((s->blocks[y * s->nbx + x] - 1) & 1) > 0) {
542 ret = decode_value(s, s->sxy_model[0], 16, 100, &sx1);
543 ret |= decode_value(s, s->sxy_model[1], 16, 100, &sy1);
544 ret |= decode_value(s, s->sxy_model[2], 16, 100, &sx2);
545 ret |= decode_value(s, s->sxy_model[3], 16, 100, &sy2);
546 if (ret < 0)
547 return ret;
548
549 sx2++;
550 sy2++;
551 }
552 if (((s->blocks[y * s->nbx + x] - 1) & 2) > 0) {
553 int i, j, by = y * 16, bx = x * 16;
554 int mvx, mvy;
555
556 ret = decode_value(s, s->mv_model[0], 512, 100, &mvx);
557 ret |= decode_value(s, s->mv_model[1], 512, 100, &mvy);
558 if (ret < 0)
559 return ret;
560
561 mvx -= 256;
562 mvy -= 256;
563
564 if (by + mvy + sy1 < 0 || bx + mvx + sx1 < 0 ||
565 by + mvy + sy1 >= avctx->height || bx + mvx + sx1 >= avctx->width)
566 return AVERROR_INVALIDDATA;
567
568 for (i = 0; i < sy2 - sy1 && (by + sy1 + i) < avctx->height && (by + mvy + sy1 + i) < avctx->height; i++) {
569 for (j = 0; j < sx2 - sx1 && (bx + sx1 + j) < avctx->width && (bx + mvx + sx1 + j) < avctx->width; j++) {
570 dst[(by + i + sy1) * linesize + bx + sx1 + j] = prev[(by + mvy + sy1 + i) * plinesize + bx + sx1 + mvx + j];
571 }
572 }
573 } else {
574 int run, r, g, b, z, bx = x * 16 + sx1, by = y * 16 + sy1;
575 unsigned clr, ptype = 0;
576
577 for (; by < y * 16 + sy2 && by < avctx->height;) {
578 ret = decode_value(s, s->op_model[ptype], 6, 1000, &ptype);
579 if (ptype == 0) {
580 ret = decode_unit(s, &s->pixel_model[0][cx + cx1], 400, &r);
581 if (ret < 0)
582 return ret;
583
584 cx1 = (cx << 6) & 0xFC0;
585 cx = r >> cxshift;
586 ret = decode_unit(s, &s->pixel_model[1][cx + cx1], 400, &g);
587 if (ret < 0)
588 return ret;
589
590 cx1 = (cx << 6) & 0xFC0;
591 cx = g >> cxshift;
592 ret = decode_unit(s, &s->pixel_model[2][cx + cx1], 400, &b);
593 if (ret < 0)
594 return ret;
595
596 clr = (b << 16) + (g << 8) + r;
597 }
598 if (ptype > 5)
599 return AVERROR_INVALIDDATA;
600 ret = decode_value(s, s->run_model[ptype], 256, 400, &run);
601 if (ret < 0)
602 return ret;
603
604 switch (ptype) {
605 case 0:
606 while (run-- > 0) {
607 if (by >= avctx->height)
608 return AVERROR_INVALIDDATA;
609
610 dst[by * linesize + bx] = clr;
611 bx++;
612 if (bx >= x * 16 + sx2 || bx >= avctx->width) {
613 bx = x * 16 + sx1;
614 by++;
615 }
616 }
617 break;
618 case 1:
619 while (run-- > 0) {
620 if (bx == 0) {
621 if (by < 1)
622 return AVERROR_INVALIDDATA;
623 z = backstep;
624 } else {
625 z = 0;
626 }
627
628 if (by >= avctx->height)
629 return AVERROR_INVALIDDATA;
630
631 clr = dst[by * linesize + bx - 1 - z];
632 dst[by * linesize + bx] = clr;
633 bx++;
634 if (bx >= x * 16 + sx2 || bx >= avctx->width) {
635 bx = x * 16 + sx1;
636 by++;
637 }
638 }
639 break;
640 case 2:
641 while (run-- > 0) {
642 if (by < 1 || by >= avctx->height)
643 return AVERROR_INVALIDDATA;
644
645 clr = dst[(by - 1) * linesize + bx];
646 dst[by * linesize + bx] = clr;
647 bx++;
648 if (bx >= x * 16 + sx2 || bx >= avctx->width) {
649 bx = x * 16 + sx1;
650 by++;
651 }
652 }
653 break;
654 case 3:
655 while (run-- > 0) {
656 if (by >= avctx->height)
657 return AVERROR_INVALIDDATA;
658
659 clr = prev[by * plinesize + bx];
660 dst[by * linesize + bx] = clr;
661 bx++;
662 if (bx >= x * 16 + sx2 || bx >= avctx->width) {
663 bx = x * 16 + sx1;
664 by++;
665 }
666 }
667 break;
668 case 4:
669 while (run-- > 0) {
670 uint8_t *odst = (uint8_t *)dst;
671
672 if (by < 1 || by >= avctx->height)
673 return AVERROR_INVALIDDATA;
674
675 if (bx == 0) {
676 z = backstep;
677 } else {
678 z = 0;
679 }
680
681 r = odst[((by - 1) * linesize + bx) * 4] +
682 odst[(by * linesize + bx - 1 - z) * 4] -
683 odst[((by - 1) * linesize + bx - 1 - z) * 4];
684 g = odst[((by - 1) * linesize + bx) * 4 + 1] +
685 odst[(by * linesize + bx - 1 - z) * 4 + 1] -
686 odst[((by - 1) * linesize + bx - 1 - z) * 4 + 1];
687 b = odst[((by - 1) * linesize + bx) * 4 + 2] +
688 odst[(by * linesize + bx - 1 - z) * 4 + 2] -
689 odst[((by - 1) * linesize + bx - 1 - z) * 4 + 2];
690 clr = ((b & 0xFF) << 16) + ((g & 0xFF) << 8) + (r & 0xFF);
691 dst[by * linesize + bx] = clr;
692 bx++;
693 if (bx >= x * 16 + sx2 || bx >= avctx->width) {
694 bx = x * 16 + sx1;
695 by++;
696 }
697 }
698 break;
699 case 5:
700 while (run-- > 0) {
701 if (by < 1 || by >= avctx->height)
702 return AVERROR_INVALIDDATA;
703
704 if (bx == 0) {
705 z = backstep;
706 } else {
707 z = 0;
708 }
709
710 clr = dst[(by - 1) * linesize + bx - 1 - z];
711 dst[by * linesize + bx] = clr;
712 bx++;
713 if (bx >= x * 16 + sx2 || bx >= avctx->width) {
714 bx = x * 16 + sx1;
715 by++;
716 }
717 }
718 break;
719 }
720
721 if (avctx->bits_per_coded_sample == 16) {
722 cx1 = (clr & 0x3F00) >> 2;
723 cx = (clr & 0xFFFFFF) >> 16;
724 } else {
725 cx1 = (clr & 0xFC00) >> 4;
726 cx = (clr & 0xFFFFFF) >> 18;
727 }
728 }
729 }
730 }
731 }
732
733 return 0;
734}
735
736static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
737 AVPacket *avpkt)
738{
739 SCPRContext *s = avctx->priv_data;
740 GetByteContext *gb = &s->gb;
741 AVFrame *frame = data;
742 int ret, type;
743
744 if (avctx->bits_per_coded_sample == 16) {
745 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
746 return ret;
747 }
748
749 if ((ret = ff_reget_buffer(avctx, s->current_frame)) < 0)
750 return ret;
751
752 bytestream2_init(gb, avpkt->data, avpkt->size);
753
754 type = bytestream2_peek_byte(gb);
755
756 if (type == 2) {
757 s->get_freq = get_freq0;
758 s->decode = decode0;
759 frame->key_frame = 1;
760 ret = decompress_i(avctx, (uint32_t *)s->current_frame->data[0],
761 s->current_frame->linesize[0] / 4);
762 } else if (type == 18) {
763 s->get_freq = get_freq;
764 s->decode = decode;
765 frame->key_frame = 1;
766 ret = decompress_i(avctx, (uint32_t *)s->current_frame->data[0],
767 s->current_frame->linesize[0] / 4);
768 } else if (type == 17) {
769 uint32_t clr, *dst = (uint32_t *)s->current_frame->data[0];
770 int x, y;
771
772 frame->key_frame = 1;
773 bytestream2_skip(gb, 1);
774 if (avctx->bits_per_coded_sample == 16) {
775 uint16_t value = bytestream2_get_le16(gb);
776 int r, g, b;
777
778 r = (value ) & 31;
779 g = (value >> 5) & 31;
780 b = (value >> 10) & 31;
781 clr = (r << 16) + (g << 8) + b;
782 } else {
783 clr = bytestream2_get_le24(gb);
784 }
785 for (y = 0; y < avctx->height; y++) {
786 for (x = 0; x < avctx->width; x++) {
787 dst[x] = clr;
788 }
789 dst += s->current_frame->linesize[0] / 4;
790 }
791 } else if (type == 0 || type == 1) {
792 frame->key_frame = 0;
793
794 ret = av_frame_copy(s->current_frame, s->last_frame);
795 if (ret < 0)
796 return ret;
797
798 ret = decompress_p(avctx, (uint32_t *)s->current_frame->data[0],
799 s->current_frame->linesize[0] / 4,
800 (uint32_t *)s->last_frame->data[0],
801 s->last_frame->linesize[0] / 4);
802 } else {
803 return AVERROR_PATCHWELCOME;
804 }
805
806 if (ret < 0)
807 return ret;
808
809 if (avctx->bits_per_coded_sample != 16) {
810 ret = av_frame_ref(data, s->current_frame);
811 if (ret < 0)
812 return ret;
813 } else {
814 uint8_t *dst = frame->data[0];
815 int x, y;
816
817 ret = av_frame_copy(frame, s->current_frame);
818 if (ret < 0)
819 return ret;
820
821 for (y = 0; y < avctx->height; y++) {
822 for (x = 0; x < avctx->width * 4; x++) {
823 dst[x] = dst[x] << 3;
824 }
825 dst += frame->linesize[0];
826 }
827 }
828
829 frame->pict_type = frame->key_frame ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
830
831 FFSWAP(AVFrame *, s->current_frame, s->last_frame);
832
833 frame->data[0] += frame->linesize[0] * (avctx->height - 1);
834 frame->linesize[0] *= -1;
835
836 *got_frame = 1;
837
838 return avpkt->size;
839}
840
841static av_cold int decode_init(AVCodecContext *avctx)
842{
843 SCPRContext *s = avctx->priv_data;
844
845 switch (avctx->bits_per_coded_sample) {
846 case 16: avctx->pix_fmt = AV_PIX_FMT_RGB0; break;
847 case 24:
848 case 32: avctx->pix_fmt = AV_PIX_FMT_BGR0; break;
849 default:
850 av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", avctx->bits_per_coded_sample);
851 return AVERROR_INVALIDDATA;
852 }
853
854 s->get_freq = get_freq0;
855 s->decode = decode0;
856
857 s->cxshift = avctx->bits_per_coded_sample == 16 ? 0 : 2;
858 s->cbits = avctx->bits_per_coded_sample == 16 ? 0x1F : 0xFF;
859 s->nbx = (avctx->width + 15) / 16;
860 s->nby = (avctx->height + 15) / 16;
861 s->nbcount = s->nbx * s->nby;
862 s->blocks = av_malloc_array(s->nbcount, sizeof(*s->blocks));
863 if (!s->blocks)
864 return AVERROR(ENOMEM);
865
866 s->last_frame = av_frame_alloc();
867 s->current_frame = av_frame_alloc();
868 if (!s->last_frame || !s->current_frame)
869 return AVERROR(ENOMEM);
870
871 return 0;
872}
873
874static av_cold int decode_close(AVCodecContext *avctx)
875{
876 SCPRContext *s = avctx->priv_data;
877
878 av_freep(&s->blocks);
879 av_frame_free(&s->last_frame);
880 av_frame_free(&s->current_frame);
881
882 return 0;
883}
884
885AVCodec ff_scpr_decoder = {
886 .name = "scpr",
887 .long_name = NULL_IF_CONFIG_SMALL("ScreenPressor"),
888 .type = AVMEDIA_TYPE_VIDEO,
889 .id = AV_CODEC_ID_SCPR,
890 .priv_data_size = sizeof(SCPRContext),
891 .init = decode_init,
892 .close = decode_close,
893 .decode = decode_frame,
894 .capabilities = AV_CODEC_CAP_DR1,
895 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
896 FF_CODEC_CAP_INIT_CLEANUP,
897};
898
generated by cgit at 2024-05-17 04:13:28 (GMT)