FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/rasc.c
Date: 2026-05-17 16:27:21
Exec Total Coverage
Lines: 0 474 0.0%
Functions: 0 15 0.0%
Branches: 0 300 0.0%

Line Branch Exec Source
1 /*
2 * RemotelyAnywhere Screen Capture decoder
3 *
4 * Copyright (c) 2018 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 <string.h>
25
26 #include "libavutil/mem.h"
27 #include "libavutil/opt.h"
28
29 #include "avcodec.h"
30 #include "bytestream.h"
31 #include "codec_internal.h"
32 #include "decode.h"
33 #include "zlib_wrapper.h"
34
35 #include <zlib.h>
36
37 #define KBND MKTAG('K', 'B', 'N', 'D')
38 #define FINT MKTAG('F', 'I', 'N', 'T')
39 #define INIT MKTAG('I', 'N', 'I', 'T')
40 #define BNDL MKTAG('B', 'N', 'D', 'L')
41 #define KFRM MKTAG('K', 'F', 'R', 'M')
42 #define DLTA MKTAG('D', 'L', 'T', 'A')
43 #define MOUS MKTAG('M', 'O', 'U', 'S')
44 #define MPOS MKTAG('M', 'P', 'O', 'S')
45 #define MOVE MKTAG('M', 'O', 'V', 'E')
46 #define EMPT MKTAG('E', 'M', 'P', 'T')
47
48 typedef struct RASCContext {
49 AVClass *class;
50 int skip_cursor;
51 GetByteContext gb;
52 uint8_t *delta;
53 int delta_size;
54 uint8_t *mv_scratch;
55 unsigned int mv_scratch_size;
56 uint8_t *cursor;
57 int cursor_size;
58 unsigned cursor_w;
59 unsigned cursor_h;
60 unsigned cursor_x;
61 unsigned cursor_y;
62 int stride;
63 int bpp;
64 AVFrame *frame;
65 AVFrame *frame1;
66 AVFrame *frame2;
67 FFZStream zstream;
68 } RASCContext;
69
70 static void clear_plane(AVCodecContext *avctx, AVFrame *frame)
71 {
72 RASCContext *s = avctx->priv_data;
73 uint8_t *dst = frame->data[0];
74
75 if (!dst)
76 return;
77
78 for (int y = 0; y < avctx->height; y++) {
79 memset(dst, 0, avctx->width * s->bpp);
80 dst += frame->linesize[0];
81 }
82 }
83
84 static void copy_plane(AVCodecContext *avctx, AVFrame *src, AVFrame *dst)
85 {
86 RASCContext *s = avctx->priv_data;
87 uint8_t *srcp = src->data[0];
88 uint8_t *dstp = dst->data[0];
89
90 for (int y = 0; y < avctx->height; y++) {
91 memcpy(dstp, srcp, s->stride);
92 srcp += src->linesize[0];
93 dstp += dst->linesize[0];
94 }
95 }
96
97 static int init_frames(AVCodecContext *avctx)
98 {
99 RASCContext *s = avctx->priv_data;
100 int ret;
101
102 av_frame_unref(s->frame1);
103 av_frame_unref(s->frame2);
104 if ((ret = ff_get_buffer(avctx, s->frame1, 0)) < 0)
105 return ret;
106
107 if ((ret = ff_get_buffer(avctx, s->frame2, 0)) < 0)
108 return ret;
109
110 clear_plane(avctx, s->frame2);
111 clear_plane(avctx, s->frame1);
112
113 return 0;
114 }
115
116 static int decode_fint(AVCodecContext *avctx,
117 const AVPacket *avpkt, unsigned size)
118 {
119 RASCContext *s = avctx->priv_data;
120 GetByteContext *gb = &s->gb;
121 unsigned w, h, fmt;
122 int ret;
123
124 if (bytestream2_peek_le32(gb) != 0x65) {
125 if (!s->frame2->data[0] || !s->frame1->data[0])
126 return AVERROR_INVALIDDATA;
127
128 clear_plane(avctx, s->frame2);
129 clear_plane(avctx, s->frame1);
130 return 0;
131 }
132 if (bytestream2_get_bytes_left(gb) < 72)
133 return AVERROR_INVALIDDATA;
134
135 bytestream2_skip(gb, 8);
136 w = bytestream2_get_le32(gb);
137 h = bytestream2_get_le32(gb);
138 bytestream2_skip(gb, 30);
139 fmt = bytestream2_get_le16(gb);
140 bytestream2_skip(gb, 24);
141
142 switch (fmt) {
143 case 8: s->stride = FFALIGN(w, 4);
144 s->bpp = 1;
145 fmt = AV_PIX_FMT_PAL8; break;
146 case 16: s->stride = w * 2;
147 s->bpp = 2;
148 fmt = AV_PIX_FMT_RGB555LE; break;
149 case 32: s->stride = w * 4;
150 s->bpp = 4;
151 fmt = AV_PIX_FMT_BGR0; break;
152 default: return AVERROR_INVALIDDATA;
153 }
154
155 ret = ff_set_dimensions(avctx, w, h);
156 if (ret < 0)
157 return ret;
158 avctx->width = w;
159 avctx->height = h;
160 avctx->pix_fmt = fmt;
161
162 ret = init_frames(avctx);
163 if (ret < 0)
164 return ret;
165
166 if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
167 uint32_t *pal = (uint32_t *)s->frame2->data[1];
168
169 for (int i = 0; i < 256; i++)
170 pal[i] = bytestream2_get_le32(gb) | 0xFF000000u;
171 }
172
173 return 0;
174 }
175
176 static int decode_zlib(AVCodecContext *avctx, const AVPacket *avpkt,
177 unsigned size, unsigned uncompressed_size)
178 {
179 RASCContext *s = avctx->priv_data;
180 z_stream *const zstream = &s->zstream.zstream;
181 GetByteContext *gb = &s->gb;
182 int zret;
183
184 zret = inflateReset(zstream);
185 if (zret != Z_OK) {
186 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
187 return AVERROR_EXTERNAL;
188 }
189
190 av_fast_padded_malloc(&s->delta, &s->delta_size, uncompressed_size);
191 if (!s->delta)
192 return AVERROR(ENOMEM);
193
194 zstream->next_in = avpkt->data + bytestream2_tell(gb);
195 zstream->avail_in = FFMIN(size, bytestream2_get_bytes_left(gb));
196
197 zstream->next_out = s->delta;
198 zstream->avail_out = s->delta_size;
199
200 zret = inflate(zstream, Z_FINISH);
201 if (zret != Z_STREAM_END) {
202 av_log(avctx, AV_LOG_ERROR,
203 "Inflate failed with return code: %d.\n", zret);
204 return AVERROR_INVALIDDATA;
205 }
206
207 return 0;
208 }
209
210 static int decode_move(AVCodecContext *avctx,
211 const AVPacket *avpkt, unsigned size)
212 {
213 RASCContext *s = avctx->priv_data;
214 GetByteContext *gb = &s->gb;
215 GetByteContext mc;
216 unsigned pos, compression, nb_moves;
217 unsigned uncompressed_size;
218 int ret;
219
220 pos = bytestream2_tell(gb);
221 bytestream2_skip(gb, 8);
222 nb_moves = bytestream2_get_le32(gb);
223 bytestream2_skip(gb, 8);
224 compression = bytestream2_get_le32(gb);
225
226 if (nb_moves > INT32_MAX / 16 || nb_moves > avctx->width * avctx->height)
227 return AVERROR_INVALIDDATA;
228
229 uncompressed_size = 16 * nb_moves;
230
231 if (compression == 1) {
232 ret = decode_zlib(avctx, avpkt,
233 size - (bytestream2_tell(gb) - pos),
234 uncompressed_size);
235 if (ret < 0)
236 return ret;
237 bytestream2_init(&mc, s->delta, uncompressed_size);
238 } else if (compression == 0) {
239 bytestream2_init(&mc, avpkt->data + bytestream2_tell(gb),
240 bytestream2_get_bytes_left(gb));
241 } else if (compression == 2) {
242 avpriv_request_sample(avctx, "compression %d", compression);
243 return AVERROR_PATCHWELCOME;
244 } else {
245 return AVERROR_INVALIDDATA;
246 }
247
248 if (bytestream2_get_bytes_left(&mc) < uncompressed_size)
249 return AVERROR_INVALIDDATA;
250
251 for (int i = 0; i < nb_moves; i++) {
252 int type, start_x, start_y, end_x, end_y, mov_x, mov_y;
253 uint8_t *e2, *b1, *b2;
254 int w, h;
255
256 type = bytestream2_get_le16(&mc);
257 start_x = bytestream2_get_le16(&mc);
258 start_y = bytestream2_get_le16(&mc);
259 end_x = bytestream2_get_le16(&mc);
260 end_y = bytestream2_get_le16(&mc);
261 mov_x = bytestream2_get_le16(&mc);
262 mov_y = bytestream2_get_le16(&mc);
263 bytestream2_skip(&mc, 2);
264
265 if (start_x >= avctx->width || start_y >= avctx->height ||
266 end_x >= avctx->width || end_y >= avctx->height ||
267 mov_x >= avctx->width || mov_y >= avctx->height) {
268 continue;
269 }
270
271 if (start_x >= end_x || start_y >= end_y)
272 continue;
273
274 w = end_x - start_x;
275 h = end_y - start_y;
276
277 if (mov_x + w > avctx->width || mov_y + h > avctx->height)
278 continue;
279
280 if (!s->frame2->data[0] || !s->frame1->data[0])
281 return AVERROR_INVALIDDATA;
282
283 b1 = s->frame1->data[0] + s->frame1->linesize[0] * (start_y + h - 1) + start_x * s->bpp;
284 b2 = s->frame2->data[0] + s->frame2->linesize[0] * (start_y + h - 1) + start_x * s->bpp;
285 e2 = s->frame2->data[0] + s->frame2->linesize[0] * (mov_y + h - 1) + mov_x * s->bpp;
286
287 if (type == 2) {
288 for (int j = 0; j < h; j++) {
289 memcpy(b1, b2, w * s->bpp);
290 b1 -= s->frame1->linesize[0];
291 b2 -= s->frame2->linesize[0];
292 }
293 } else if (type == 1) {
294 for (int j = 0; j < h; j++) {
295 memset(b2, 0, w * s->bpp);
296 b2 -= s->frame2->linesize[0];
297 }
298 } else if (type == 0) {
299 av_fast_padded_malloc(&s->mv_scratch, &s->mv_scratch_size, w * h * s->bpp);
300 uint8_t *buffer = s->mv_scratch;
301 if (!buffer)
302 return AVERROR(ENOMEM);
303
304 for (int j = 0; j < h; j++) {
305 memcpy(buffer + j * w * s->bpp, e2, w * s->bpp);
306 e2 -= s->frame2->linesize[0];
307 }
308
309 for (int j = 0; j < h; j++) {
310 memcpy(b2, buffer + j * w * s->bpp, w * s->bpp);
311 b2 -= s->frame2->linesize[0];
312 }
313 } else {
314 return AVERROR_INVALIDDATA;
315 }
316 }
317
318 bytestream2_skip(gb, size - (bytestream2_tell(gb) - pos));
319
320 return 0;
321 }
322
323 #define NEXT_LINE \
324 if (cx >= w * s->bpp) { \
325 cx = 0; \
326 cy--; \
327 b1 -= s->frame1->linesize[0]; \
328 b2 -= s->frame2->linesize[0]; \
329 } \
330 len--;
331
332 static int decode_dlta(AVCodecContext *avctx,
333 const AVPacket *avpkt, unsigned size)
334 {
335 RASCContext *s = avctx->priv_data;
336 GetByteContext *gb = &s->gb;
337 GetByteContext dc;
338 unsigned uncompressed_size, pos;
339 unsigned x, y, w, h;
340 int ret, cx, cy, compression;
341 uint8_t *b1, *b2;
342
343 pos = bytestream2_tell(gb);
344 bytestream2_skip(gb, 12);
345 uncompressed_size = bytestream2_get_le32(gb);
346 x = bytestream2_get_le32(gb);
347 y = bytestream2_get_le32(gb);
348 w = bytestream2_get_le32(gb);
349 h = bytestream2_get_le32(gb);
350
351 if (x >= avctx->width || y >= avctx->height ||
352 w > avctx->width || h > avctx->height)
353 return AVERROR_INVALIDDATA;
354
355 if (x + w > avctx->width || y + h > avctx->height)
356 return AVERROR_INVALIDDATA;
357
358 bytestream2_skip(gb, 4);
359 compression = bytestream2_get_le32(gb);
360
361 if (compression == 1) {
362 if (w * h * s->bpp * 3 < uncompressed_size)
363 return AVERROR_INVALIDDATA;
364 ret = decode_zlib(avctx, avpkt, size, uncompressed_size);
365 if (ret < 0)
366 return ret;
367 bytestream2_init(&dc, s->delta, uncompressed_size);
368 } else if (compression == 0) {
369 if (bytestream2_get_bytes_left(gb) < uncompressed_size)
370 return AVERROR_INVALIDDATA;
371 bytestream2_init(&dc, avpkt->data + bytestream2_tell(gb),
372 uncompressed_size);
373 } else if (compression == 2) {
374 avpriv_request_sample(avctx, "compression %d", compression);
375 return AVERROR_PATCHWELCOME;
376 } else {
377 return AVERROR_INVALIDDATA;
378 }
379
380 if (!s->frame2->data[0] || !s->frame1->data[0])
381 return AVERROR_INVALIDDATA;
382
383 b1 = s->frame1->data[0] + s->frame1->linesize[0] * (int)(y + h - 1) + ((int)x) * s->bpp;
384 b2 = s->frame2->data[0] + s->frame2->linesize[0] * (int)(y + h - 1) + ((int)x) * s->bpp;
385 cx = 0, cy = h;
386 while (bytestream2_get_bytes_left(&dc) > 0) {
387 int type = bytestream2_get_byte(&dc);
388 int len = bytestream2_get_byte(&dc);
389 unsigned fill;
390
391 switch (type) {
392 case 1:
393 while (len > 0 && cy > 0) {
394 cx++;
395 NEXT_LINE
396 }
397 break;
398 case 2:
399 while (len > 0 && cy > 0) {
400 int v0 = b1[cx];
401 int v1 = b2[cx];
402
403 b2[cx] = v0;
404 b1[cx] = v1;
405 cx++;
406 NEXT_LINE
407 }
408 break;
409 case 3:
410 while (len > 0 && cy > 0) {
411 fill = bytestream2_get_byte(&dc);
412 b1[cx] = b2[cx];
413 b2[cx] = fill;
414 cx++;
415 NEXT_LINE
416 }
417 break;
418 case 4:
419 fill = bytestream2_get_byte(&dc);
420 while (len > 0 && cy > 0) {
421 AV_WL32(b1 + cx, AV_RL32(b2 + cx));
422 AV_WL32(b2 + cx, fill);
423 cx++;
424 NEXT_LINE
425 }
426 break;
427 case 7:
428 fill = bytestream2_get_le32(&dc);
429 while (len > 0 && cy > 0) {
430 AV_WL32(b1 + cx, AV_RL32(b2 + cx));
431 AV_WL32(b2 + cx, fill);
432 cx += 4;
433 NEXT_LINE
434 }
435 break;
436 case 10:
437 while (len > 0 && cy > 0) {
438 cx += 4;
439 NEXT_LINE
440 }
441 break;
442 case 12:
443 while (len > 0 && cy > 0) {
444 unsigned v0, v1;
445
446 v0 = AV_RL32(b2 + cx);
447 v1 = AV_RL32(b1 + cx);
448 AV_WL32(b2 + cx, v1);
449 AV_WL32(b1 + cx, v0);
450 cx += 4;
451 NEXT_LINE
452 }
453 break;
454 case 13:
455 while (len > 0 && cy > 0) {
456 fill = bytestream2_get_le32(&dc);
457 AV_WL32(b1 + cx, AV_RL32(b2 + cx));
458 AV_WL32(b2 + cx, fill);
459 cx += 4;
460 NEXT_LINE
461 }
462 break;
463 default:
464 avpriv_request_sample(avctx, "runlen %d", type);
465 return AVERROR_INVALIDDATA;
466 }
467 }
468
469 bytestream2_skip(gb, size - (bytestream2_tell(gb) - pos));
470
471 return 0;
472 }
473
474 static int decode_kfrm(AVCodecContext *avctx,
475 const AVPacket *avpkt, unsigned size)
476 {
477 RASCContext *s = avctx->priv_data;
478 z_stream *const zstream = &s->zstream.zstream;
479 GetByteContext *gb = &s->gb;
480 uint8_t *dst;
481 unsigned pos;
482 int zret, ret;
483
484 pos = bytestream2_tell(gb);
485 if (bytestream2_peek_le32(gb) == 0x65) {
486 ret = decode_fint(avctx, avpkt, size);
487 if (ret < 0)
488 return ret;
489 }
490
491 if (!s->frame2->data[0])
492 return AVERROR_INVALIDDATA;
493
494 zret = inflateReset(zstream);
495 if (zret != Z_OK) {
496 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
497 return AVERROR_EXTERNAL;
498 }
499
500 zstream->next_in = avpkt->data + bytestream2_tell(gb);
501 zstream->avail_in = bytestream2_get_bytes_left(gb);
502
503 dst = s->frame2->data[0] + (avctx->height - 1) * s->frame2->linesize[0];
504 for (int i = 0; i < avctx->height; i++) {
505 zstream->next_out = dst;
506 zstream->avail_out = s->stride;
507
508 zret = inflate(zstream, Z_SYNC_FLUSH);
509 if (zret != Z_OK && zret != Z_STREAM_END) {
510 av_log(avctx, AV_LOG_ERROR,
511 "Inflate failed with return code: %d.\n", zret);
512 return AVERROR_INVALIDDATA;
513 }
514
515 dst -= s->frame2->linesize[0];
516 }
517
518 dst = s->frame1->data[0] + (avctx->height - 1) * s->frame1->linesize[0];
519 for (int i = 0; i < avctx->height; i++) {
520 zstream->next_out = dst;
521 zstream->avail_out = s->stride;
522
523 zret = inflate(zstream, Z_SYNC_FLUSH);
524 if (zret != Z_OK && zret != Z_STREAM_END) {
525 av_log(avctx, AV_LOG_ERROR,
526 "Inflate failed with return code: %d.\n", zret);
527 return AVERROR_INVALIDDATA;
528 }
529
530 dst -= s->frame1->linesize[0];
531 }
532
533 bytestream2_skip(gb, size - (bytestream2_tell(gb) - pos));
534
535 return 0;
536 }
537
538 static int decode_mous(AVCodecContext *avctx,
539 const AVPacket *avpkt, unsigned size)
540 {
541 RASCContext *s = avctx->priv_data;
542 GetByteContext *gb = &s->gb;
543 unsigned w, h, pos, uncompressed_size;
544 int ret;
545
546 pos = bytestream2_tell(gb);
547 bytestream2_skip(gb, 8);
548 w = bytestream2_get_le32(gb);
549 h = bytestream2_get_le32(gb);
550 bytestream2_skip(gb, 12);
551 uncompressed_size = bytestream2_get_le32(gb);
552
553 if (w > avctx->width || h > avctx->height)
554 return AVERROR_INVALIDDATA;
555
556 if (uncompressed_size != 3 * w * h)
557 return AVERROR_INVALIDDATA;
558
559 av_fast_padded_malloc(&s->cursor, &s->cursor_size, uncompressed_size);
560 if (!s->cursor)
561 return AVERROR(ENOMEM);
562
563 ret = decode_zlib(avctx, avpkt,
564 size - (bytestream2_tell(gb) - pos),
565 uncompressed_size);
566 if (ret < 0)
567 return ret;
568 memcpy(s->cursor, s->delta, uncompressed_size);
569
570 bytestream2_skip(gb, size - (bytestream2_tell(gb) - pos));
571
572 s->cursor_w = w;
573 s->cursor_h = h;
574
575 return 0;
576 }
577
578 static int decode_mpos(AVCodecContext *avctx,
579 const AVPacket *avpkt, unsigned size)
580 {
581 RASCContext *s = avctx->priv_data;
582 GetByteContext *gb = &s->gb;
583 unsigned pos;
584
585 pos = bytestream2_tell(gb);
586 bytestream2_skip(gb, 8);
587 s->cursor_x = bytestream2_get_le32(gb);
588 s->cursor_y = bytestream2_get_le32(gb);
589
590 bytestream2_skip(gb, size - (bytestream2_tell(gb) - pos));
591
592 return 0;
593 }
594
595 static void draw_cursor(AVCodecContext *avctx)
596 {
597 RASCContext *s = avctx->priv_data;
598 uint8_t *dst, *pal;
599
600 if (!s->cursor)
601 return;
602
603 if (s->cursor_x >= avctx->width || s->cursor_y >= avctx->height)
604 return;
605
606 if (s->cursor_x + s->cursor_w > avctx->width ||
607 s->cursor_y + s->cursor_h > avctx->height)
608 return;
609
610 if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
611 pal = s->frame->data[1];
612 for (int i = 0; i < s->cursor_h; i++) {
613 for (int j = 0; j < s->cursor_w; j++) {
614 int cr = s->cursor[3 * s->cursor_w * (s->cursor_h - i - 1) + 3 * j + 0];
615 int cg = s->cursor[3 * s->cursor_w * (s->cursor_h - i - 1) + 3 * j + 1];
616 int cb = s->cursor[3 * s->cursor_w * (s->cursor_h - i - 1) + 3 * j + 2];
617 int best = INT_MAX;
618 int index = 0;
619 int dist;
620
621 if (cr == s->cursor[0] && cg == s->cursor[1] && cb == s->cursor[2])
622 continue;
623
624 dst = s->frame->data[0] + s->frame->linesize[0] * (int)(s->cursor_y + i) + (int)(s->cursor_x + j);
625 for (int k = 0; k < 256; k++) {
626 int pr = pal[k * 4 + 0];
627 int pg = pal[k * 4 + 1];
628 int pb = pal[k * 4 + 2];
629
630 dist = FFABS(cr - pr) + FFABS(cg - pg) + FFABS(cb - pb);
631 if (dist < best) {
632 best = dist;
633 index = k;
634 }
635 }
636 dst[0] = index;
637 }
638 }
639 } else if (avctx->pix_fmt == AV_PIX_FMT_RGB555LE) {
640 for (int i = 0; i < s->cursor_h; i++) {
641 for (int j = 0; j < s->cursor_w; j++) {
642 int cr = s->cursor[3 * s->cursor_w * (s->cursor_h - i - 1) + 3 * j + 0];
643 int cg = s->cursor[3 * s->cursor_w * (s->cursor_h - i - 1) + 3 * j + 1];
644 int cb = s->cursor[3 * s->cursor_w * (s->cursor_h - i - 1) + 3 * j + 2];
645
646 if (cr == s->cursor[0] && cg == s->cursor[1] && cb == s->cursor[2])
647 continue;
648
649 cr >>= 3; cg >>=3; cb >>= 3;
650 dst = s->frame->data[0] + s->frame->linesize[0] * (int)(s->cursor_y + i) + 2 * (s->cursor_x + j);
651 AV_WL16(dst, cr | cg << 5 | cb << 10);
652 }
653 }
654 } else if (avctx->pix_fmt == AV_PIX_FMT_BGR0) {
655 for (int i = 0; i < s->cursor_h; i++) {
656 for (int j = 0; j < s->cursor_w; j++) {
657 int cr = s->cursor[3 * s->cursor_w * (s->cursor_h - i - 1) + 3 * j + 0];
658 int cg = s->cursor[3 * s->cursor_w * (s->cursor_h - i - 1) + 3 * j + 1];
659 int cb = s->cursor[3 * s->cursor_w * (s->cursor_h - i - 1) + 3 * j + 2];
660
661 if (cr == s->cursor[0] && cg == s->cursor[1] && cb == s->cursor[2])
662 continue;
663
664 dst = s->frame->data[0] + s->frame->linesize[0] * (int)(s->cursor_y + i) + 4 * (s->cursor_x + j);
665 dst[0] = cb;
666 dst[1] = cg;
667 dst[2] = cr;
668 }
669 }
670 }
671 }
672
673 static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
674 int *got_frame, AVPacket *avpkt)
675 {
676 RASCContext *s = avctx->priv_data;
677 GetByteContext *gb = &s->gb;
678 int ret, intra = 0;
679
680 bytestream2_init(gb, avpkt->data, avpkt->size);
681
682 if (bytestream2_peek_le32(gb) == EMPT)
683 return avpkt->size;
684
685 s->frame = frame;
686
687 while (bytestream2_get_bytes_left(gb) > 0) {
688 unsigned type, size = 0;
689
690 if (bytestream2_get_bytes_left(gb) < 8)
691 return AVERROR_INVALIDDATA;
692
693 type = bytestream2_get_le32(gb);
694 if (type == KBND || type == BNDL) {
695 intra = type == KBND;
696 type = bytestream2_get_le32(gb);
697 }
698
699 size = bytestream2_get_le32(gb);
700 if (bytestream2_get_bytes_left(gb) < size)
701 return AVERROR_INVALIDDATA;
702
703 switch (type) {
704 case FINT:
705 case INIT:
706 ret = decode_fint(avctx, avpkt, size);
707 break;
708 case KFRM:
709 ret = decode_kfrm(avctx, avpkt, size);
710 break;
711 case DLTA:
712 ret = decode_dlta(avctx, avpkt, size);
713 break;
714 case MOVE:
715 ret = decode_move(avctx, avpkt, size);
716 break;
717 case MOUS:
718 ret = decode_mous(avctx, avpkt, size);
719 break;
720 case MPOS:
721 ret = decode_mpos(avctx, avpkt, size);
722 break;
723 default:
724 bytestream2_skip(gb, size);
725 ret = 0;
726 }
727
728 if (ret < 0)
729 return ret;
730 }
731
732 if (!s->frame2->data[0] || !s->frame1->data[0])
733 return AVERROR_INVALIDDATA;
734
735 if ((ret = ff_get_buffer(avctx, s->frame, 0)) < 0)
736 return ret;
737
738 copy_plane(avctx, s->frame2, s->frame);
739 if (avctx->pix_fmt == AV_PIX_FMT_PAL8)
740 memcpy(s->frame->data[1], s->frame2->data[1], 1024);
741 if (!s->skip_cursor)
742 draw_cursor(avctx);
743
744 if (intra)
745 s->frame->flags |= AV_FRAME_FLAG_KEY;
746 else
747 s->frame->flags &= ~AV_FRAME_FLAG_KEY;
748 s->frame->pict_type = intra ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
749
750 *got_frame = 1;
751
752 return avpkt->size;
753 }
754
755 static av_cold int decode_init(AVCodecContext *avctx)
756 {
757 RASCContext *s = avctx->priv_data;
758
759 s->frame1 = av_frame_alloc();
760 s->frame2 = av_frame_alloc();
761 if (!s->frame1 || !s->frame2)
762 return AVERROR(ENOMEM);
763
764 return ff_inflate_init(&s->zstream, avctx);
765 }
766
767 static av_cold int decode_close(AVCodecContext *avctx)
768 {
769 RASCContext *s = avctx->priv_data;
770
771 av_freep(&s->cursor);
772 s->cursor_size = 0;
773 av_freep(&s->delta);
774 s->delta_size = 0;
775 av_freep(&s->mv_scratch);
776 s->mv_scratch_size = 0;
777 av_frame_free(&s->frame1);
778 av_frame_free(&s->frame2);
779 ff_inflate_end(&s->zstream);
780
781 return 0;
782 }
783
784 static av_cold void decode_flush(AVCodecContext *avctx)
785 {
786 RASCContext *s = avctx->priv_data;
787
788 clear_plane(avctx, s->frame1);
789 clear_plane(avctx, s->frame2);
790 }
791
792 static const AVOption options[] = {
793 { "skip_cursor", "skip the cursor", offsetof(RASCContext, skip_cursor), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM },
794 { NULL },
795 };
796
797 static const AVClass rasc_decoder_class = {
798 .class_name = "rasc decoder",
799 .item_name = av_default_item_name,
800 .option = options,
801 .version = LIBAVUTIL_VERSION_INT,
802 };
803
804 const FFCodec ff_rasc_decoder = {
805 .p.name = "rasc",
806 CODEC_LONG_NAME("RemotelyAnywhere Screen Capture"),
807 .p.type = AVMEDIA_TYPE_VIDEO,
808 .p.id = AV_CODEC_ID_RASC,
809 .priv_data_size = sizeof(RASCContext),
810 .init = decode_init,
811 .close = decode_close,
812 FF_CODEC_DECODE_CB(decode_frame),
813 .flush = decode_flush,
814 .p.capabilities = AV_CODEC_CAP_DR1,
815 .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
816 .p.priv_class = &rasc_decoder_class,
817 };
818