FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/scpr.c
Date: 2021-09-23 20:34:37
Exec Total Coverage
Lines: 0 418 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 "internal.h"
30 #include "scpr.h"
31 #include "scpr3.h"
32
33 #define TOP 0x01000000
34 #define BOT 0x010000
35
36 #include "scpr3.c"
37
38 static void init_rangecoder(RangeCoder *rc, GetByteContext *gb)
39 {
40 rc->code1 = 0;
41 rc->range = 0xFFFFFFFFU;
42 rc->code = bytestream2_get_be32(gb);
43 }
44
45 static void reinit_tables(SCPRContext *s)
46 {
47 int comp, i, j;
48
49 for (comp = 0; comp < 3; comp++) {
50 for (j = 0; j < 4096; j++) {
51 if (s->pixel_model[comp][j].total_freq != 256) {
52 for (i = 0; i < 256; i++)
53 s->pixel_model[comp][j].freq[i] = 1;
54 for (i = 0; i < 16; i++)
55 s->pixel_model[comp][j].lookup[i] = 16;
56 s->pixel_model[comp][j].total_freq = 256;
57 }
58 }
59 }
60
61 for (j = 0; j < 6; j++) {
62 uint32_t *p = s->run_model[j];
63 for (i = 0; i < 256; i++)
64 p[i] = 1;
65 p[256] = 256;
66 }
67
68 for (j = 0; j < 6; j++) {
69 uint32_t *op = s->op_model[j];
70 for (i = 0; i < 6; i++)
71 op[i] = 1;
72 op[6] = 6;
73 }
74
75 for (i = 0; i < 256; i++) {
76 s->range_model[i] = 1;
77 s->count_model[i] = 1;
78 }
79 s->range_model[256] = 256;
80 s->count_model[256] = 256;
81
82 for (i = 0; i < 5; i++) {
83 s->fill_model[i] = 1;
84 }
85 s->fill_model[5] = 5;
86
87 for (j = 0; j < 4; j++) {
88 for (i = 0; i < 16; i++) {
89 s->sxy_model[j][i] = 1;
90 }
91 s->sxy_model[j][16] = 16;
92 }
93
94 for (i = 0; i < 512; i++) {
95 s->mv_model[0][i] = 1;
96 s->mv_model[1][i] = 1;
97 }
98 s->mv_model[0][512] = 512;
99 s->mv_model[1][512] = 512;
100 }
101
102 static int decode(GetByteContext *gb, RangeCoder *rc, uint32_t cumFreq, uint32_t freq, uint32_t total_freq)
103 {
104 rc->code -= cumFreq * rc->range;
105 rc->range *= freq;
106
107 while (rc->range < TOP && bytestream2_get_bytes_left(gb) > 0) {
108 uint32_t byte = bytestream2_get_byteu(gb);
109 rc->code = (rc->code << 8) | byte;
110 rc->range <<= 8;
111 }
112
113 return 0;
114 }
115
116 static int get_freq(RangeCoder *rc, uint32_t total_freq, uint32_t *freq)
117 {
118 if (total_freq == 0)
119 return AVERROR_INVALIDDATA;
120
121 rc->range = rc->range / total_freq;
122
123 if (rc->range == 0)
124 return AVERROR_INVALIDDATA;
125
126 *freq = rc->code / rc->range;
127
128 return 0;
129 }
130
131 static int decode0(GetByteContext *gb, RangeCoder *rc, uint32_t cumFreq, uint32_t freq, uint32_t total_freq)
132 {
133 uint32_t t;
134
135 if (total_freq == 0)
136 return AVERROR_INVALIDDATA;
137
138 t = rc->range * (uint64_t)cumFreq / total_freq;
139
140 rc->code1 += t + 1;
141 rc->range = rc->range * (uint64_t)(freq + cumFreq) / total_freq - (t + 1);
142
143 while (rc->range < TOP && bytestream2_get_bytes_left(gb) > 0) {
144 uint32_t byte = bytestream2_get_byteu(gb);
145 rc->code = (rc->code << 8) | byte;
146 rc->code1 <<= 8;
147 rc->range <<= 8;
148 }
149
150 return 0;
151 }
152
153 static int get_freq0(RangeCoder *rc, uint32_t total_freq, uint32_t *freq)
154 {
155 if (rc->range == 0)
156 return AVERROR_INVALIDDATA;
157
158 *freq = total_freq * (uint64_t)(rc->code - rc->code1) / rc->range;
159
160 return 0;
161 }
162
163 static int decode_value(SCPRContext *s, uint32_t *cnt, uint32_t maxc, uint32_t step, uint32_t *rval)
164 {
165 GetByteContext *gb = &s->gb;
166 RangeCoder *rc = &s->rc;
167 uint32_t totfr = cnt[maxc];
168 uint32_t value;
169 uint32_t c = 0, cumfr = 0, cnt_c = 0;
170 int i, ret;
171
172 if ((ret = s->get_freq(rc, totfr, &value)) < 0)
173 return ret;
174
175 while (c < maxc) {
176 cnt_c = cnt[c];
177 if (value >= cumfr + cnt_c)
178 cumfr += cnt_c;
179 else
180 break;
181 c++;
182 }
183
184 if (c >= maxc)
185 return AVERROR_INVALIDDATA;
186
187 if ((ret = s->decode(gb, rc, cumfr, cnt_c, totfr)) < 0)
188 return ret;
189
190 cnt[c] = cnt_c + step;
191 totfr += step;
192 if (totfr > BOT) {
193 totfr = 0;
194 for (i = 0; i < maxc; i++) {
195 uint32_t nc = (cnt[i] >> 1) + 1;
196 cnt[i] = nc;
197 totfr += nc;
198 }
199 }
200
201 cnt[maxc] = totfr;
202 *rval = c;
203
204 return 0;
205 }
206
207 static int decode_unit(SCPRContext *s, PixelModel *pixel, uint32_t step, uint32_t *rval)
208 {
209 GetByteContext *gb = &s->gb;
210 RangeCoder *rc = &s->rc;
211 uint32_t totfr = pixel->total_freq;
212 uint32_t value, x = 0, cumfr = 0, cnt_x = 0;
213 int i, j, ret, c, cnt_c;
214
215 if ((ret = s->get_freq(rc, totfr, &value)) < 0)
216 return ret;
217
218 while (x < 16) {
219 cnt_x = pixel->lookup[x];
220 if (value >= cumfr + cnt_x)
221 cumfr += cnt_x;
222 else
223 break;
224 x++;
225 }
226
227 c = x * 16;
228 cnt_c = 0;
229 while (c < 256) {
230 cnt_c = pixel->freq[c];
231 if (value >= cumfr + cnt_c)
232 cumfr += cnt_c;
233 else
234 break;
235 c++;
236 }
237 if (x >= 16 || c >= 256) {
238 return AVERROR_INVALIDDATA;
239 }
240
241 if ((ret = s->decode(gb, rc, cumfr, cnt_c, totfr)) < 0)
242 return ret;
243
244 pixel->freq[c] = cnt_c + step;
245 pixel->lookup[x] = cnt_x + step;
246 totfr += step;
247 if (totfr > BOT) {
248 totfr = 0;
249 for (i = 0; i < 256; i++) {
250 uint32_t nc = (pixel->freq[i] >> 1) + 1;
251 pixel->freq[i] = nc;
252 totfr += nc;
253 }
254 for (i = 0; i < 16; i++) {
255 uint32_t sum = 0;
256 uint32_t i16_17 = i << 4;
257 for (j = 0; j < 16; j++)
258 sum += pixel->freq[i16_17 + j];
259 pixel->lookup[i] = sum;
260 }
261 }
262 pixel->total_freq = totfr;
263
264 *rval = c & s->cbits;
265
266 return 0;
267 }
268
269 static int decode_units(SCPRContext *s, uint32_t *r, uint32_t *g, uint32_t *b,
270 int *cx, int *cx1)
271 {
272 const int cxshift = s->cxshift;
273 int ret;
274
275 ret = decode_unit(s, &s->pixel_model[0][*cx + *cx1], 400, r);
276 if (ret < 0)
277 return ret;
278
279 *cx1 = (*cx << 6) & 0xFC0;
280 *cx = *r >> cxshift;
281 ret = decode_unit(s, &s->pixel_model[1][*cx + *cx1], 400, g);
282 if (ret < 0)
283 return ret;
284
285 *cx1 = (*cx << 6) & 0xFC0;
286 *cx = *g >> cxshift;
287 ret = decode_unit(s, &s->pixel_model[2][*cx + *cx1], 400, b);
288 if (ret < 0)
289 return ret;
290
291 *cx1 = (*cx << 6) & 0xFC0;
292 *cx = *b >> cxshift;
293
294 return 0;
295 }
296
297 static int decompress_i(AVCodecContext *avctx, uint32_t *dst, int linesize)
298 {
299 SCPRContext *s = avctx->priv_data;
300 GetByteContext *gb = &s->gb;
301 int cx = 0, cx1 = 0, k = 0;
302 int run, off, y = 0, x = 0, ret;
303 uint32_t clr = 0, r, g, b, backstep = linesize - avctx->width;
304 uint32_t lx, ly, ptype;
305
306 reinit_tables(s);
307 bytestream2_skip(gb, 2);
308 init_rangecoder(&s->rc, gb);
309
310 while (k < avctx->width + 1) {
311 ret = decode_units(s, &r, &g, &b, &cx, &cx1);
312 if (ret < 0)
313 return ret;
314
315 ret = decode_value(s, s->run_model[0], 256, 400, &run);
316 if (ret < 0)
317 return ret;
318 if (run <= 0)
319 return AVERROR_INVALIDDATA;
320
321 clr = (b << 16) + (g << 8) + r;
322 k += run;
323 while (run-- > 0) {
324 if (y >= avctx->height)
325 return AVERROR_INVALIDDATA;
326
327 dst[y * linesize + x] = clr;
328 lx = x;
329 ly = y;
330 x++;
331 if (x >= avctx->width) {
332 x = 0;
333 y++;
334 }
335 }
336 }
337 off = -linesize - 1;
338 ptype = 0;
339
340 while (x < avctx->width && y < avctx->height) {
341 ret = decode_value(s, s->op_model[ptype], 6, 1000, &ptype);
342 if (ret < 0)
343 return ret;
344 if (ptype == 0) {
345 ret = decode_units(s, &r, &g, &b, &cx, &cx1);
346 if (ret < 0)
347 return ret;
348
349 clr = (b << 16) + (g << 8) + r;
350 }
351 if (ptype > 5)
352 return AVERROR_INVALIDDATA;
353 ret = decode_value(s, s->run_model[ptype], 256, 400, &run);
354 if (ret < 0)
355 return ret;
356 if (run <= 0)
357 return AVERROR_INVALIDDATA;
358
359 ret = decode_run_i(avctx, ptype, run, &x, &y, clr,
360 dst, linesize, &lx, &ly,
361 backstep, off, &cx, &cx1);
362 if (ret < 0)
363 return ret;
364 }
365
366 return 0;
367 }
368
369 static int decompress_p(AVCodecContext *avctx,
370 uint32_t *dst, int linesize,
371 uint32_t *prev, int plinesize)
372 {
373 SCPRContext *s = avctx->priv_data;
374 GetByteContext *gb = &s->gb;
375 int ret, temp = 0, min, max, x, y, cx = 0, cx1 = 0;
376 int backstep = linesize - avctx->width;
377
378 if (bytestream2_get_byte(gb) == 0)
379 return 1;
380 bytestream2_skip(gb, 1);
381 init_rangecoder(&s->rc, gb);
382
383 ret = decode_value(s, s->range_model, 256, 1, &min);
384 ret |= decode_value(s, s->range_model, 256, 1, &temp);
385 if (ret < 0)
386 return ret;
387
388 min += temp << 8;
389 ret = decode_value(s, s->range_model, 256, 1, &max);
390 ret |= decode_value(s, s->range_model, 256, 1, &temp);
391 if (ret < 0)
392 return ret;
393
394 max += temp << 8;
395 if (min > max || min >= s->nbcount)
396 return AVERROR_INVALIDDATA;
397
398 memset(s->blocks, 0, sizeof(*s->blocks) * s->nbcount);
399
400 while (min <= max) {
401 int fill, count;
402
403 ret = decode_value(s, s->fill_model, 5, 10, &fill);
404 ret |= decode_value(s, s->count_model, 256, 20, &count);
405 if (ret < 0)
406 return ret;
407 if (count <= 0)
408 return AVERROR_INVALIDDATA;
409
410 while (min < s->nbcount && count-- > 0) {
411 s->blocks[min++] = fill;
412 }
413 }
414
415 ret = av_frame_copy(s->current_frame, s->last_frame);
416 if (ret < 0)
417 return ret;
418
419 for (y = 0; y < s->nby; y++) {
420 for (x = 0; x < s->nbx; x++) {
421 int sy1 = 0, sy2 = 16, sx1 = 0, sx2 = 16;
422
423 if (s->blocks[y * s->nbx + x] == 0)
424 continue;
425
426 if (((s->blocks[y * s->nbx + x] - 1) & 1) > 0) {
427 ret = decode_value(s, s->sxy_model[0], 16, 100, &sx1);
428 ret |= decode_value(s, s->sxy_model[1], 16, 100, &sy1);
429 ret |= decode_value(s, s->sxy_model[2], 16, 100, &sx2);
430 ret |= decode_value(s, s->sxy_model[3], 16, 100, &sy2);
431 if (ret < 0)
432 return ret;
433
434 sx2++;
435 sy2++;
436 }
437 if (((s->blocks[y * s->nbx + x] - 1) & 2) > 0) {
438 int i, j, by = y * 16, bx = x * 16;
439 int mvx, mvy;
440
441 ret = decode_value(s, s->mv_model[0], 512, 100, &mvx);
442 ret |= decode_value(s, s->mv_model[1], 512, 100, &mvy);
443 if (ret < 0)
444 return ret;
445
446 mvx -= 256;
447 mvy -= 256;
448
449 if (by + mvy + sy1 < 0 || bx + mvx + sx1 < 0 ||
450 by + mvy + sy1 >= avctx->height || bx + mvx + sx1 >= avctx->width)
451 return AVERROR_INVALIDDATA;
452
453 for (i = 0; i < sy2 - sy1 && (by + sy1 + i) < avctx->height && (by + mvy + sy1 + i) < avctx->height; i++) {
454 for (j = 0; j < sx2 - sx1 && (bx + sx1 + j) < avctx->width && (bx + mvx + sx1 + j) < avctx->width; j++) {
455 dst[(by + i + sy1) * linesize + bx + sx1 + j] = prev[(by + mvy + sy1 + i) * plinesize + bx + sx1 + mvx + j];
456 }
457 }
458 } else {
459 int run, bx = x * 16 + sx1, by = y * 16 + sy1;
460 uint32_t r, g, b, clr, ptype = 0;
461
462 for (; by < y * 16 + sy2 && by < avctx->height;) {
463 ret = decode_value(s, s->op_model[ptype], 6, 1000, &ptype);
464 if (ret < 0)
465 return ret;
466 if (ptype == 0) {
467 ret = decode_units(s, &r, &g, &b, &cx, &cx1);
468 if (ret < 0)
469 return ret;
470
471 clr = (b << 16) + (g << 8) + r;
472 }
473 if (ptype > 5)
474 return AVERROR_INVALIDDATA;
475 ret = decode_value(s, s->run_model[ptype], 256, 400, &run);
476 if (ret < 0)
477 return ret;
478 if (run <= 0)
479 return AVERROR_INVALIDDATA;
480
481 ret = decode_run_p(avctx, ptype, run, x, y, clr,
482 dst, prev, linesize, plinesize, &bx, &by,
483 backstep, sx1, sx2, &cx, &cx1);
484 if (ret < 0)
485 return ret;
486 }
487 }
488 }
489 }
490
491 return 0;
492 }
493
494 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
495 AVPacket *avpkt)
496 {
497 SCPRContext *s = avctx->priv_data;
498 GetByteContext *gb = &s->gb;
499 AVFrame *frame = data;
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(data, 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 AVCodec ff_scpr_decoder = {
671 .name = "scpr",
672 .long_name = NULL_IF_CONFIG_SMALL("ScreenPressor"),
673 .type = AVMEDIA_TYPE_VIDEO,
674 .id = AV_CODEC_ID_SCPR,
675 .priv_data_size = sizeof(SCPRContext),
676 .init = decode_init,
677 .close = decode_close,
678 .decode = decode_frame,
679 .capabilities = AV_CODEC_CAP_DR1,
680 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
681 FF_CODEC_CAP_INIT_CLEANUP,
682 };
683