FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/scpr.c
Date: 2022-07-05 19:52:29
Exec Total Coverage
Lines: 0 417 0.0%
Branches: 0 259 0.0%

Line Branch Exec Source
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 "codec_internal.h"
30 #include "internal.h"
31 #include "scpr.h"
32 #include "scpr3.h"
33
34 #define TOP 0x01000000
35 #define BOT 0x010000
36
37 #include "scpr3.c"
38
39 static void init_rangecoder(RangeCoder *rc, GetByteContext *gb)
40 {
41 rc->code1 = 0;
42 rc->range = 0xFFFFFFFFU;
43 rc->code = bytestream2_get_be32(gb);
44 }
45
46 static void reinit_tables(SCPRContext *s)
47 {
48 int comp, i, j;
49
50 for (comp = 0; comp < 3; comp++) {
51 for (j = 0; j < 4096; j++) {
52 if (s->pixel_model[comp][j].total_freq != 256) {
53 for (i = 0; i < 256; i++)
54 s->pixel_model[comp][j].freq[i] = 1;
55 for (i = 0; i < 16; i++)
56 s->pixel_model[comp][j].lookup[i] = 16;
57 s->pixel_model[comp][j].total_freq = 256;
58 }
59 }
60 }
61
62 for (j = 0; j < 6; j++) {
63 uint32_t *p = s->run_model[j];
64 for (i = 0; i < 256; i++)
65 p[i] = 1;
66 p[256] = 256;
67 }
68
69 for (j = 0; j < 6; j++) {
70 uint32_t *op = s->op_model[j];
71 for (i = 0; i < 6; i++)
72 op[i] = 1;
73 op[6] = 6;
74 }
75
76 for (i = 0; i < 256; i++) {
77 s->range_model[i] = 1;
78 s->count_model[i] = 1;
79 }
80 s->range_model[256] = 256;
81 s->count_model[256] = 256;
82
83 for (i = 0; i < 5; i++) {
84 s->fill_model[i] = 1;
85 }
86 s->fill_model[5] = 5;
87
88 for (j = 0; j < 4; j++) {
89 for (i = 0; i < 16; i++) {
90 s->sxy_model[j][i] = 1;
91 }
92 s->sxy_model[j][16] = 16;
93 }
94
95 for (i = 0; i < 512; i++) {
96 s->mv_model[0][i] = 1;
97 s->mv_model[1][i] = 1;
98 }
99 s->mv_model[0][512] = 512;
100 s->mv_model[1][512] = 512;
101 }
102
103 static int decode(GetByteContext *gb, RangeCoder *rc, uint32_t cumFreq, uint32_t freq, uint32_t total_freq)
104 {
105 rc->code -= cumFreq * rc->range;
106 rc->range *= freq;
107
108 while (rc->range < TOP && bytestream2_get_bytes_left(gb) > 0) {
109 uint32_t byte = bytestream2_get_byteu(gb);
110 rc->code = (rc->code << 8) | byte;
111 rc->range <<= 8;
112 }
113
114 return 0;
115 }
116
117 static int get_freq(RangeCoder *rc, uint32_t total_freq, uint32_t *freq)
118 {
119 if (total_freq == 0)
120 return AVERROR_INVALIDDATA;
121
122 rc->range = rc->range / total_freq;
123
124 if (rc->range == 0)
125 return AVERROR_INVALIDDATA;
126
127 *freq = rc->code / rc->range;
128
129 return 0;
130 }
131
132 static int decode0(GetByteContext *gb, RangeCoder *rc, uint32_t cumFreq, uint32_t freq, uint32_t total_freq)
133 {
134 uint32_t t;
135
136 if (total_freq == 0)
137 return AVERROR_INVALIDDATA;
138
139 t = rc->range * (uint64_t)cumFreq / total_freq;
140
141 rc->code1 += t + 1;
142 rc->range = rc->range * (uint64_t)(freq + cumFreq) / total_freq - (t + 1);
143
144 while (rc->range < TOP && bytestream2_get_bytes_left(gb) > 0) {
145 uint32_t byte = bytestream2_get_byteu(gb);
146 rc->code = (rc->code << 8) | byte;
147 rc->code1 <<= 8;
148 rc->range <<= 8;
149 }
150
151 return 0;
152 }
153
154 static int get_freq0(RangeCoder *rc, uint32_t total_freq, uint32_t *freq)
155 {
156 if (rc->range == 0)
157 return AVERROR_INVALIDDATA;
158
159 *freq = total_freq * (uint64_t)(rc->code - rc->code1) / rc->range;
160
161 return 0;
162 }
163
164 static int decode_value(SCPRContext *s, uint32_t *cnt, uint32_t maxc, uint32_t step, uint32_t *rval)
165 {
166 GetByteContext *gb = &s->gb;
167 RangeCoder *rc = &s->rc;
168 uint32_t totfr = cnt[maxc];
169 uint32_t value;
170 uint32_t c = 0, cumfr = 0, cnt_c = 0;
171 int i, ret;
172
173 if ((ret = s->get_freq(rc, totfr, &value)) < 0)
174 return ret;
175
176 while (c < maxc) {
177 cnt_c = cnt[c];
178 if (value >= cumfr + cnt_c)
179 cumfr += cnt_c;
180 else
181 break;
182 c++;
183 }
184
185 if (c >= maxc)
186 return AVERROR_INVALIDDATA;
187
188 if ((ret = s->decode(gb, rc, cumfr, cnt_c, totfr)) < 0)
189 return ret;
190
191 cnt[c] = cnt_c + step;
192 totfr += step;
193 if (totfr > BOT) {
194 totfr = 0;
195 for (i = 0; i < maxc; i++) {
196 uint32_t nc = (cnt[i] >> 1) + 1;
197 cnt[i] = nc;
198 totfr += nc;
199 }
200 }
201
202 cnt[maxc] = totfr;
203 *rval = c;
204
205 return 0;
206 }
207
208 static int decode_unit(SCPRContext *s, PixelModel *pixel, uint32_t step, uint32_t *rval)
209 {
210 GetByteContext *gb = &s->gb;
211 RangeCoder *rc = &s->rc;
212 uint32_t totfr = pixel->total_freq;
213 uint32_t value, x = 0, cumfr = 0, cnt_x = 0;
214 int i, j, ret, c, cnt_c;
215
216 if ((ret = s->get_freq(rc, totfr, &value)) < 0)
217 return ret;
218
219 while (x < 16) {
220 cnt_x = pixel->lookup[x];
221 if (value >= cumfr + cnt_x)
222 cumfr += cnt_x;
223 else
224 break;
225 x++;
226 }
227
228 c = x * 16;
229 cnt_c = 0;
230 while (c < 256) {
231 cnt_c = pixel->freq[c];
232 if (value >= cumfr + cnt_c)
233 cumfr += cnt_c;
234 else
235 break;
236 c++;
237 }
238 if (x >= 16 || c >= 256) {
239 return AVERROR_INVALIDDATA;
240 }
241
242 if ((ret = s->decode(gb, rc, cumfr, cnt_c, totfr)) < 0)
243 return ret;
244
245 pixel->freq[c] = cnt_c + step;
246 pixel->lookup[x] = cnt_x + step;
247 totfr += step;
248 if (totfr > BOT) {
249 totfr = 0;
250 for (i = 0; i < 256; i++) {
251 uint32_t nc = (pixel->freq[i] >> 1) + 1;
252 pixel->freq[i] = nc;
253 totfr += nc;
254 }
255 for (i = 0; i < 16; i++) {
256 uint32_t sum = 0;
257 uint32_t i16_17 = i << 4;
258 for (j = 0; j < 16; j++)
259 sum += pixel->freq[i16_17 + j];
260 pixel->lookup[i] = sum;
261 }
262 }
263 pixel->total_freq = totfr;
264
265 *rval = c & s->cbits;
266
267 return 0;
268 }
269
270 static int decode_units(SCPRContext *s, uint32_t *r, uint32_t *g, uint32_t *b,
271 int *cx, int *cx1)
272 {
273 const int cxshift = s->cxshift;
274 int ret;
275
276 ret = decode_unit(s, &s->pixel_model[0][*cx + *cx1], 400, r);
277 if (ret < 0)
278 return ret;
279
280 *cx1 = (*cx << 6) & 0xFC0;
281 *cx = *r >> cxshift;
282 ret = decode_unit(s, &s->pixel_model[1][*cx + *cx1], 400, g);
283 if (ret < 0)
284 return ret;
285
286 *cx1 = (*cx << 6) & 0xFC0;
287 *cx = *g >> cxshift;
288 ret = decode_unit(s, &s->pixel_model[2][*cx + *cx1], 400, b);
289 if (ret < 0)
290 return ret;
291
292 *cx1 = (*cx << 6) & 0xFC0;
293 *cx = *b >> cxshift;
294
295 return 0;
296 }
297
298 static int decompress_i(AVCodecContext *avctx, uint32_t *dst, int linesize)
299 {
300 SCPRContext *s = avctx->priv_data;
301 GetByteContext *gb = &s->gb;
302 int cx = 0, cx1 = 0, k = 0;
303 int run, off, y = 0, x = 0, ret;
304 uint32_t clr = 0, r, g, b, backstep = linesize - avctx->width;
305 uint32_t lx, ly, ptype;
306
307 reinit_tables(s);
308 bytestream2_skip(gb, 2);
309 init_rangecoder(&s->rc, gb);
310
311 while (k < avctx->width + 1) {
312 ret = decode_units(s, &r, &g, &b, &cx, &cx1);
313 if (ret < 0)
314 return ret;
315
316 ret = decode_value(s, s->run_model[0], 256, 400, &run);
317 if (ret < 0)
318 return ret;
319 if (run <= 0)
320 return AVERROR_INVALIDDATA;
321
322 clr = (b << 16) + (g << 8) + r;
323 k += run;
324 while (run-- > 0) {
325 if (y >= avctx->height)
326 return AVERROR_INVALIDDATA;
327
328 dst[y * linesize + x] = clr;
329 lx = x;
330 ly = y;
331 x++;
332 if (x >= avctx->width) {
333 x = 0;
334 y++;
335 }
336 }
337 }
338 off = -linesize - 1;
339 ptype = 0;
340
341 while (x < avctx->width && y < avctx->height) {
342 ret = decode_value(s, s->op_model[ptype], 6, 1000, &ptype);
343 if (ret < 0)
344 return ret;
345 if (ptype == 0) {
346 ret = decode_units(s, &r, &g, &b, &cx, &cx1);
347 if (ret < 0)
348 return ret;
349
350 clr = (b << 16) + (g << 8) + r;
351 }
352 if (ptype > 5)
353 return AVERROR_INVALIDDATA;
354 ret = decode_value(s, s->run_model[ptype], 256, 400, &run);
355 if (ret < 0)
356 return ret;
357 if (run <= 0)
358 return AVERROR_INVALIDDATA;
359
360 ret = decode_run_i(avctx, ptype, run, &x, &y, clr,
361 dst, linesize, &lx, &ly,
362 backstep, off, &cx, &cx1);
363 if (ret < 0)
364 return ret;
365 }
366
367 return 0;
368 }
369
370 static int decompress_p(AVCodecContext *avctx,
371 uint32_t *dst, int linesize,
372 uint32_t *prev, int plinesize)
373 {
374 SCPRContext *s = avctx->priv_data;
375 GetByteContext *gb = &s->gb;
376 int ret, temp = 0, min, max, x, y, cx = 0, cx1 = 0;
377 int backstep = linesize - avctx->width;
378
379 if (bytestream2_get_byte(gb) == 0)
380 return 1;
381 bytestream2_skip(gb, 1);
382 init_rangecoder(&s->rc, gb);
383
384 ret = decode_value(s, s->range_model, 256, 1, &min);
385 ret |= decode_value(s, s->range_model, 256, 1, &temp);
386 if (ret < 0)
387 return ret;
388
389 min += temp << 8;
390 ret = decode_value(s, s->range_model, 256, 1, &max);
391 ret |= decode_value(s, s->range_model, 256, 1, &temp);
392 if (ret < 0)
393 return ret;
394
395 max += temp << 8;
396 if (min > max || min >= s->nbcount)
397 return AVERROR_INVALIDDATA;
398
399 memset(s->blocks, 0, sizeof(*s->blocks) * s->nbcount);
400
401 while (min <= max) {
402 int fill, count;
403
404 ret = decode_value(s, s->fill_model, 5, 10, &fill);
405 ret |= decode_value(s, s->count_model, 256, 20, &count);
406 if (ret < 0)
407 return ret;
408 if (count <= 0)
409 return AVERROR_INVALIDDATA;
410
411 while (min < s->nbcount && count-- > 0) {
412 s->blocks[min++] = fill;
413 }
414 }
415
416 ret = av_frame_copy(s->current_frame, s->last_frame);
417 if (ret < 0)
418 return ret;
419
420 for (y = 0; y < s->nby; y++) {
421 for (x = 0; x < s->nbx; x++) {
422 int sy1 = 0, sy2 = 16, sx1 = 0, sx2 = 16;
423
424 if (s->blocks[y * s->nbx + x] == 0)
425 continue;
426
427 if (((s->blocks[y * s->nbx + x] - 1) & 1) > 0) {
428 ret = decode_value(s, s->sxy_model[0], 16, 100, &sx1);
429 ret |= decode_value(s, s->sxy_model[1], 16, 100, &sy1);
430 ret |= decode_value(s, s->sxy_model[2], 16, 100, &sx2);
431 ret |= decode_value(s, s->sxy_model[3], 16, 100, &sy2);
432 if (ret < 0)
433 return ret;
434
435 sx2++;
436 sy2++;
437 }
438 if (((s->blocks[y * s->nbx + x] - 1) & 2) > 0) {
439 int i, j, by = y * 16, bx = x * 16;
440 int mvx, mvy;
441
442 ret = decode_value(s, s->mv_model[0], 512, 100, &mvx);
443 ret |= decode_value(s, s->mv_model[1], 512, 100, &mvy);
444 if (ret < 0)
445 return ret;
446
447 mvx -= 256;
448 mvy -= 256;
449
450 if (by + mvy + sy1 < 0 || bx + mvx + sx1 < 0 ||
451 by + mvy + sy1 >= avctx->height || bx + mvx + sx1 >= avctx->width)
452 return AVERROR_INVALIDDATA;
453
454 for (i = 0; i < sy2 - sy1 && (by + sy1 + i) < avctx->height && (by + mvy + sy1 + i) < avctx->height; i++) {
455 for (j = 0; j < sx2 - sx1 && (bx + sx1 + j) < avctx->width && (bx + mvx + sx1 + j) < avctx->width; j++) {
456 dst[(by + i + sy1) * linesize + bx + sx1 + j] = prev[(by + mvy + sy1 + i) * plinesize + bx + sx1 + mvx + j];
457 }
458 }
459 } else {
460 int run, bx = x * 16 + sx1, by = y * 16 + sy1;
461 uint32_t r, g, b, clr, ptype = 0;
462
463 for (; by < y * 16 + sy2 && by < avctx->height;) {
464 ret = decode_value(s, s->op_model[ptype], 6, 1000, &ptype);
465 if (ret < 0)
466 return ret;
467 if (ptype == 0) {
468 ret = decode_units(s, &r, &g, &b, &cx, &cx1);
469 if (ret < 0)
470 return ret;
471
472 clr = (b << 16) + (g << 8) + r;
473 }
474 if (ptype > 5)
475 return AVERROR_INVALIDDATA;
476 ret = decode_value(s, s->run_model[ptype], 256, 400, &run);
477 if (ret < 0)
478 return ret;
479 if (run <= 0)
480 return AVERROR_INVALIDDATA;
481
482 ret = decode_run_p(avctx, ptype, run, x, y, clr,
483 dst, prev, linesize, plinesize, &bx, &by,
484 backstep, sx1, sx2, &cx, &cx1);
485 if (ret < 0)
486 return ret;
487 }
488 }
489 }
490 }
491
492 return 0;
493 }
494
495 static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
496 int *got_frame, AVPacket *avpkt)
497 {
498 SCPRContext *s = avctx->priv_data;
499 GetByteContext *gb = &s->gb;
500 int ret, type;
501
502 if (avctx->bits_per_coded_sample == 16) {
503 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
504 return ret;
505 }
506
507 if ((ret = ff_reget_buffer(avctx, s->current_frame, 0)) < 0)
508 return ret;
509
510 bytestream2_init(gb, avpkt->data, avpkt->size);
511
512 type = bytestream2_peek_byte(gb);
513
514 if (type == 2) {
515 s->version = 1;
516 s->get_freq = get_freq0;
517 s->decode = decode0;
518 frame->key_frame = 1;
519 ret = decompress_i(avctx, (uint32_t *)s->current_frame->data[0],
520 s->current_frame->linesize[0] / 4);
521 } else if (type == 18) {
522 s->version = 2;
523 s->get_freq = get_freq;
524 s->decode = decode;
525 frame->key_frame = 1;
526 ret = decompress_i(avctx, (uint32_t *)s->current_frame->data[0],
527 s->current_frame->linesize[0] / 4);
528 } else if (type == 34) {
529 frame->key_frame = 1;
530 s->version = 3;
531 ret = decompress_i3(avctx, (uint32_t *)s->current_frame->data[0],
532 s->current_frame->linesize[0] / 4);
533 } else if (type == 17 || type == 33) {
534 uint32_t clr, *dst = (uint32_t *)s->current_frame->data[0];
535 int y;
536
537 if (bytestream2_get_bytes_left(gb) < 3)
538 return AVERROR_INVALIDDATA;
539
540 frame->key_frame = 1;
541 bytestream2_skip(gb, 1);
542 if (avctx->bits_per_coded_sample == 16) {
543 uint16_t value = bytestream2_get_le16(gb);
544 int r, g, b;
545
546 r = (value ) & 31;
547 g = (value >> 5) & 31;
548 b = (value >> 10) & 31;
549 clr = (r << 16) + (g << 8) + b;
550 } else {
551 clr = bytestream2_get_le24(gb);
552 }
553 for (y = 0; y < avctx->height; y++) {
554 dst[0] = clr;
555 av_memcpy_backptr((uint8_t*)(dst+1), 4, 4*avctx->width - 4);
556 dst += s->current_frame->linesize[0] / 4;
557 }
558 } else if (type == 0 || type == 1) {
559 frame->key_frame = 0;
560
561 if (s->version == 1 || s->version == 2)
562 ret = decompress_p(avctx, (uint32_t *)s->current_frame->data[0],
563 s->current_frame->linesize[0] / 4,
564 (uint32_t *)s->last_frame->data[0],
565 s->last_frame->linesize[0] / 4);
566 else
567 ret = decompress_p3(avctx, (uint32_t *)s->current_frame->data[0],
568 s->current_frame->linesize[0] / 4,
569 (uint32_t *)s->last_frame->data[0],
570 s->last_frame->linesize[0] / 4);
571 if (ret == 1)
572 return avpkt->size;
573 } else {
574 return AVERROR_PATCHWELCOME;
575 }
576
577 if (ret < 0)
578 return ret;
579
580 if (bytestream2_get_bytes_left(gb) > 5)
581 return AVERROR_INVALIDDATA;
582
583 if (avctx->bits_per_coded_sample != 16) {
584 ret = av_frame_ref(frame, s->current_frame);
585 if (ret < 0)
586 return ret;
587 } else {
588 uint8_t *dst = frame->data[0];
589 int x, y;
590
591 ret = av_frame_copy(frame, s->current_frame);
592 if (ret < 0)
593 return ret;
594
595 // scale up each sample by 8
596 for (y = 0; y < avctx->height; y++) {
597 // If the image is sufficiently aligned, compute 8 samples at once
598 if (!(((uintptr_t)dst) & 7)) {
599 uint64_t *dst64 = (uint64_t *)dst;
600 int w = avctx->width>>1;
601 for (x = 0; x < w; x++) {
602 dst64[x] = (dst64[x] << 3) & 0xFCFCFCFCFCFCFCFCULL;
603 }
604 x *= 8;
605 } else
606 x = 0;
607 for (; x < avctx->width * 4; x++) {
608 dst[x] = dst[x] << 3;
609 }
610 dst += frame->linesize[0];
611 }
612 }
613
614 frame->pict_type = frame->key_frame ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
615
616 FFSWAP(AVFrame *, s->current_frame, s->last_frame);
617
618 frame->data[0] += frame->linesize[0] * (avctx->height - 1);
619 frame->linesize[0] *= -1;
620
621 *got_frame = 1;
622
623 return avpkt->size;
624 }
625
626 static av_cold int decode_init(AVCodecContext *avctx)
627 {
628 SCPRContext *s = avctx->priv_data;
629
630 switch (avctx->bits_per_coded_sample) {
631 case 16: avctx->pix_fmt = AV_PIX_FMT_RGB0; break;
632 case 24:
633 case 32: avctx->pix_fmt = AV_PIX_FMT_BGR0; break;
634 default:
635 av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", avctx->bits_per_coded_sample);
636 return AVERROR_INVALIDDATA;
637 }
638
639 s->get_freq = get_freq0;
640 s->decode = decode0;
641
642 s->cxshift = avctx->bits_per_coded_sample == 16 ? 0 : 2;
643 s->cbits = avctx->bits_per_coded_sample == 16 ? 0x1F : 0xFF;
644 s->nbx = (avctx->width + 15) / 16;
645 s->nby = (avctx->height + 15) / 16;
646 s->nbcount = s->nbx * s->nby;
647 s->blocks = av_malloc_array(s->nbcount, sizeof(*s->blocks));
648 if (!s->blocks)
649 return AVERROR(ENOMEM);
650
651 s->last_frame = av_frame_alloc();
652 s->current_frame = av_frame_alloc();
653 if (!s->last_frame || !s->current_frame)
654 return AVERROR(ENOMEM);
655
656 return 0;
657 }
658
659 static av_cold int decode_close(AVCodecContext *avctx)
660 {
661 SCPRContext *s = avctx->priv_data;
662
663 av_freep(&s->blocks);
664 av_frame_free(&s->last_frame);
665 av_frame_free(&s->current_frame);
666
667 return 0;
668 }
669
670 const FFCodec ff_scpr_decoder = {
671 .p.name = "scpr",
672 .p.long_name = NULL_IF_CONFIG_SMALL("ScreenPressor"),
673 .p.type = AVMEDIA_TYPE_VIDEO,
674 .p.id = AV_CODEC_ID_SCPR,
675 .priv_data_size = sizeof(SCPRContext),
676 .init = decode_init,
677 .close = decode_close,
678 FF_CODEC_DECODE_CB(decode_frame),
679 .p.capabilities = AV_CODEC_CAP_DR1,
680 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
681 FF_CODEC_CAP_INIT_CLEANUP,
682 };
683