FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/sga.c
Date: 2024-11-20 23:03:26
Exec Total Coverage
Lines: 0 292 0.0%
Functions: 0 10 0.0%
Branches: 0 198 0.0%

Line Branch Exec Source
1 /*
2 * Copyright (c) 2021 Paul B Mahol
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #include "libavutil/common.h"
22 #include "libavutil/mem.h"
23 #include "avcodec.h"
24 #include "get_bits.h"
25 #include "bytestream.h"
26 #include "codec_internal.h"
27 #include "decode.h"
28
29 #define PALDATA_FOLLOWS_TILEDATA 4
30 #define HAVE_COMPRESSED_TILEMAP 32
31 #define HAVE_TILEMAP 128
32
33 typedef struct SGAVideoContext {
34 GetByteContext gb;
35
36 int metadata_size;
37 int tiledata_size;
38 int tiledata_offset;
39 int tilemapdata_size;
40 int tilemapdata_offset;
41 int paldata_size;
42 int paldata_offset;
43 int palmapdata_offset;
44 int palmapdata_size;
45
46 int flags;
47 int nb_pal;
48 int nb_tiles;
49 int tiles_w, tiles_h;
50 int shift;
51 int plus;
52 int swap;
53
54 uint32_t pal[256];
55 uint8_t *tileindex_data;
56 unsigned tileindex_size;
57 uint8_t *palmapindex_data;
58 unsigned palmapindex_size;
59 uint8_t uncompressed[65536];
60 } SGAVideoContext;
61
62 static av_cold int sga_decode_init(AVCodecContext *avctx)
63 {
64 avctx->pix_fmt = AV_PIX_FMT_PAL8;
65 return 0;
66 }
67
68 static int decode_palette(GetByteContext *gb, uint32_t *pal)
69 {
70 GetBitContext gbit;
71
72 if (bytestream2_get_bytes_left(gb) < 18)
73 return AVERROR_INVALIDDATA;
74
75 memset(pal, 0, 16 * sizeof(*pal));
76 (void)init_get_bits8(&gbit, gb->buffer, 18);
77
78 for (int RGBIndex = 0; RGBIndex < 3; RGBIndex++) {
79 for (int index = 0; index < 16; index++) {
80 unsigned color = get_bits1(&gbit) << RGBIndex;
81 pal[15 - index] |= color << (5 + 16);
82 }
83 }
84
85 for (int RGBIndex = 0; RGBIndex < 3; RGBIndex++) {
86 for (int index = 0; index < 16; index++) {
87 unsigned color = get_bits1(&gbit) << RGBIndex;
88 pal[15 - index] |= color << (5 + 8);
89 }
90 }
91
92 for (int RGBIndex = 0; RGBIndex < 3; RGBIndex++) {
93 for (int index = 0; index < 16; index++) {
94 unsigned color = get_bits1(&gbit) << RGBIndex;
95 pal[15 - index] |= color << (5 + 0);
96 }
97 }
98
99 for (int index = 0; index < 16; index++)
100 pal[index] = (0xFFU << 24) | pal[index] | (pal[index] >> 3);
101
102 bytestream2_skip(gb, 18);
103
104 return 0;
105 }
106
107 static int decode_index_palmap(SGAVideoContext *s, AVFrame *frame)
108 {
109 const uint8_t *tt = s->tileindex_data;
110
111 for (int y = 0; y < s->tiles_h; y++) {
112 for (int x = 0; x < s->tiles_w; x++) {
113 int pal_idx = s->palmapindex_data[y * s->tiles_w + x] * 16;
114 uint8_t *dst = frame->data[0] + y * 8 * frame->linesize[0] + x * 8;
115
116 for (int yy = 0; yy < 8; yy++) {
117 for (int xx = 0; xx < 8; xx++)
118 dst[xx] = pal_idx + tt[xx];
119 tt += 8;
120
121 dst += frame->linesize[0];
122 }
123 }
124 }
125
126 return 0;
127 }
128
129 static int decode_index_tilemap(SGAVideoContext *s, AVFrame *frame)
130 {
131 GetByteContext *gb = &s->gb, gb2;
132
133 bytestream2_seek(gb, s->tilemapdata_offset, SEEK_SET);
134 if (bytestream2_get_bytes_left(gb) < s->tilemapdata_size)
135 return AVERROR_INVALIDDATA;
136
137 gb2 = *gb;
138
139 for (int y = 0; y < s->tiles_h; y++) {
140 for (int x = 0; x < s->tiles_w; x++) {
141 uint8_t tile[64];
142 int tilemap = bytestream2_get_be16u(&gb2);
143 int flip_x = (tilemap >> 11) & 1;
144 int flip_y = (tilemap >> 12) & 1;
145 int tindex = av_clip((tilemap & 511) - 1, 0, s->nb_tiles - 1);
146 const uint8_t *tt = s->tileindex_data + tindex * 64;
147 int pal_idx = ((tilemap >> 13) & 3) * 16;
148 uint8_t *dst = frame->data[0] + y * 8 * frame->linesize[0] + x * 8;
149
150 if (!flip_x && !flip_y) {
151 memcpy(tile, tt, 64);
152 } else if (flip_x && flip_y) {
153 for (int i = 0; i < 8; i++) {
154 for (int j = 0; j < 8; j++)
155 tile[i * 8 + j] = tt[(7 - i) * 8 + 7 - j];
156 }
157 } else if (flip_x) {
158 for (int i = 0; i < 8; i++) {
159 for (int j = 0; j < 8; j++)
160 tile[i * 8 + j] = tt[i * 8 + 7 - j];
161 }
162 } else {
163 for (int i = 0; i < 8; i++) {
164 for (int j = 0; j < 8; j++)
165 tile[i * 8 + j] = tt[(7 - i) * 8 + j];
166 }
167 }
168
169 for (int yy = 0; yy < 8; yy++) {
170 for (int xx = 0; xx < 8; xx++)
171 dst[xx] = pal_idx + tile[xx + yy * 8];
172
173 dst += frame->linesize[0];
174 }
175 }
176 }
177
178 return 0;
179 }
180
181 static int decode_index(SGAVideoContext *s, AVFrame *frame)
182 {
183 const uint8_t *src = s->tileindex_data;
184 uint8_t *dst = frame->data[0];
185
186 for (int y = 0; y < frame->height; y += 8) {
187 for (int x = 0; x < frame->width; x += 8) {
188 for (int yy = 0; yy < 8; yy++) {
189 for (int xx = 0; xx < 8; xx++)
190 dst[x + xx + yy * frame->linesize[0]] = src[xx];
191 src += 8;
192 }
193 }
194
195 dst += 8 * frame->linesize[0];
196 }
197
198 return 0;
199 }
200
201 static int lzss_decompress(AVCodecContext *avctx,
202 GetByteContext *gb, uint8_t *dst,
203 int dst_size, int shift, int plus)
204 {
205 int oi = 0;
206
207 while (bytestream2_get_bytes_left(gb) > 0 && oi < dst_size) {
208 uint16_t displace, header = bytestream2_get_be16(gb);
209 int count, offset;
210
211 for (int i = 0; i < 16; i++) {
212 switch (header >> 15) {
213 case 0:
214 if (oi + 2 < dst_size) {
215 dst[oi++] = bytestream2_get_byte(gb);
216 dst[oi++] = bytestream2_get_byte(gb);
217 }
218 break;
219 case 1:
220 displace = bytestream2_get_be16(gb);
221 count = displace >> shift;
222 offset = displace & ((1 << shift) - 1);
223
224 if (displace == 0) {
225 while (bytestream2_get_bytes_left(gb) > 0 &&
226 oi < dst_size)
227 dst[oi++] = bytestream2_get_byte(gb);
228 return oi;
229 }
230
231 count += plus;
232
233 if (offset <= 0)
234 offset = 1;
235 if (oi < offset || oi + count * 2 > dst_size)
236 return AVERROR_INVALIDDATA;
237 for (int j = 0; j < count * 2; j++) {
238 dst[oi] = dst[oi - offset];
239 oi++;
240 }
241 break;
242 }
243
244 header <<= 1;
245 }
246 }
247
248 return AVERROR_INVALIDDATA;
249 }
250
251 static int decode_palmapdata(AVCodecContext *avctx)
252 {
253 SGAVideoContext *s = avctx->priv_data;
254 const int bits = (s->nb_pal + 1) / 2;
255 GetByteContext *gb = &s->gb;
256 GetBitContext pm;
257 int ret;
258
259 bytestream2_seek(gb, s->palmapdata_offset, SEEK_SET);
260 if (bytestream2_get_bytes_left(gb) < s->palmapdata_size)
261 return AVERROR_INVALIDDATA;
262 ret = init_get_bits8(&pm, gb->buffer, s->palmapdata_size);
263 av_assert1(ret >= 0);
264
265 for (int y = 0; y < s->tiles_h; y++) {
266 uint8_t *dst = s->palmapindex_data + y * s->tiles_w;
267
268 for (int x = 0; x < s->tiles_w; x++)
269 dst[x] = get_bits(&pm, bits);
270
271 dst += s->tiles_w;
272 }
273
274 return 0;
275 }
276
277 static int decode_tiledata(AVCodecContext *avctx)
278 {
279 SGAVideoContext *s = avctx->priv_data;
280 GetByteContext *gb = &s->gb;
281 GetBitContext tm;
282 int ret;
283
284 bytestream2_seek(gb, s->tiledata_offset, SEEK_SET);
285 if (bytestream2_get_bytes_left(gb) < s->tiledata_size)
286 return AVERROR_INVALIDDATA;
287 ret = init_get_bits8(&tm, gb->buffer, s->tiledata_size);
288 av_assert1(ret >= 0);
289
290 for (int n = 0; n < s->nb_tiles; n++) {
291 uint8_t *dst = s->tileindex_data + n * 64;
292
293 for (int yy = 0; yy < 8; yy++) {
294 for (int xx = 0; xx < 8; xx++)
295 dst[xx] = get_bits(&tm, 4);
296
297 dst += 8;
298 }
299 }
300
301 for (int i = 0; i < s->nb_tiles && s->swap; i++) {
302 uint8_t *dst = s->tileindex_data + i * 64;
303
304 for (int j = 8; j < 64; j += 16) {
305 for (int k = 0; k < 8; k += 2)
306 FFSWAP(uint8_t, dst[j + k], dst[j+k+1]);
307 }
308 }
309
310 return 0;
311 }
312
313 static int sga_decode_frame(AVCodecContext *avctx, AVFrame *frame,
314 int *got_frame, AVPacket *avpkt)
315 {
316 SGAVideoContext *s = avctx->priv_data;
317 GetByteContext *gb = &s->gb;
318 int ret, type;
319
320 if (avpkt->size <= 14)
321 return AVERROR_INVALIDDATA;
322
323 s->flags = avpkt->data[8];
324 s->nb_pal = avpkt->data[9];
325 s->tiles_w = avpkt->data[10];
326 s->tiles_h = avpkt->data[11];
327
328 if (s->nb_pal > 4)
329 return AVERROR_INVALIDDATA;
330
331 if ((ret = ff_set_dimensions(avctx,
332 s->tiles_w * 8,
333 s->tiles_h * 8)) < 0)
334 return ret;
335
336 av_fast_padded_malloc(&s->tileindex_data, &s->tileindex_size,
337 avctx->width * avctx->height);
338 if (!s->tileindex_data)
339 return AVERROR(ENOMEM);
340
341 av_fast_padded_malloc(&s->palmapindex_data, &s->palmapindex_size,
342 s->tiles_w * s->tiles_h);
343 if (!s->palmapindex_data)
344 return AVERROR(ENOMEM);
345
346 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
347 return ret;
348
349 bytestream2_init(gb, avpkt->data, avpkt->size);
350
351 type = bytestream2_get_byte(gb);
352 s->metadata_size = 12 + ((!!(s->flags & HAVE_TILEMAP)) * 2);
353 s->nb_tiles = s->flags & HAVE_TILEMAP ? AV_RB16(avpkt->data + 12) : s->tiles_w * s->tiles_h;
354 if (s->nb_tiles > s->tiles_w * s->tiles_h)
355 return AVERROR_INVALIDDATA;
356
357 av_log(avctx, AV_LOG_DEBUG, "type: %X flags: %X nb_tiles: %d\n", type, s->flags, s->nb_tiles);
358
359 switch (type) {
360 case 0xE7:
361 case 0xCB:
362 case 0xCD:
363 s->swap = 1;
364 s->shift = 12;
365 s->plus = 1;
366 break;
367 case 0xC9:
368 s->swap = 1;
369 s->shift = 13;
370 s->plus = 1;
371 break;
372 case 0xC8:
373 s->swap = 1;
374 s->shift = 13;
375 s->plus = 0;
376 break;
377 case 0xC7:
378 s->swap = 0;
379 s->shift = 13;
380 s->plus = 1;
381 break;
382 case 0xC6:
383 s->swap = 0;
384 s->shift = 13;
385 s->plus = 0;
386 break;
387 }
388
389 if (type == 0xE7) {
390 int offset = s->metadata_size, left;
391 int sizes[3];
392
393 bytestream2_seek(gb, s->metadata_size, SEEK_SET);
394
395 for (int i = 0; i < 3; i++)
396 sizes[i] = bytestream2_get_be16(gb);
397
398 for (int i = 0; i < 3; i++) {
399 int size = sizes[i];
400 int raw = size >> 15;
401
402 size &= (1 << 15) - 1;
403
404 if (raw) {
405 if (bytestream2_get_bytes_left(gb) < size)
406 return AVERROR_INVALIDDATA;
407
408 if (sizeof(s->uncompressed) - offset < size)
409 return AVERROR_INVALIDDATA;
410
411 memcpy(s->uncompressed + offset, gb->buffer, size);
412 bytestream2_skip(gb, size);
413 } else {
414 GetByteContext gb2;
415
416 if (bytestream2_get_bytes_left(gb) < size)
417 return AVERROR_INVALIDDATA;
418
419 bytestream2_init(&gb2, gb->buffer, size);
420 ret = lzss_decompress(avctx, &gb2, s->uncompressed + offset,
421 sizeof(s->uncompressed) - offset, s->shift, s->plus);
422 if (ret < 0)
423 return ret;
424 bytestream2_skip(gb, size);
425 size = ret;
426 }
427
428 offset += size;
429 }
430
431 left = bytestream2_get_bytes_left(gb);
432 if (sizeof(s->uncompressed) - offset < left)
433 return AVERROR_INVALIDDATA;
434
435 bytestream2_get_buffer(gb, s->uncompressed + offset, left);
436
437 offset += left;
438 bytestream2_init(gb, s->uncompressed, offset);
439 }
440
441 switch (type) {
442 case 0xCD:
443 case 0xCB:
444 case 0xC9:
445 case 0xC8:
446 case 0xC7:
447 case 0xC6:
448 bytestream2_seek(gb, s->metadata_size, SEEK_SET);
449 ret = lzss_decompress(avctx, gb, s->uncompressed + s->metadata_size,
450 sizeof(s->uncompressed) - s->metadata_size, s->shift, s->plus);
451 if (ret < 0)
452 return ret;
453 bytestream2_init(gb, s->uncompressed, ret + s->metadata_size);
454 case 0xE7:
455 case 0xC1:
456 s->tiledata_size = s->nb_tiles * 32;
457 s->paldata_size = s->nb_pal * 18;
458 s->tiledata_offset = s->flags & PALDATA_FOLLOWS_TILEDATA ? s->metadata_size : s->metadata_size + s->paldata_size;
459 s->paldata_offset = s->flags & PALDATA_FOLLOWS_TILEDATA ? s->metadata_size + s->tiledata_size : s->metadata_size;
460 s->palmapdata_offset = (s->flags & HAVE_TILEMAP) ? -1 : s->paldata_offset + s->paldata_size;
461 s->palmapdata_size = (s->flags & HAVE_TILEMAP) || s->nb_pal < 2 ? 0 : (s->tiles_w * s->tiles_h * ((s->nb_pal + 1) / 2) + 7) / 8;
462 s->tilemapdata_size = (s->flags & HAVE_TILEMAP) ? s->tiles_w * s->tiles_h * 2 : 0;
463 s->tilemapdata_offset = (s->flags & HAVE_TILEMAP) ? s->paldata_offset + s->paldata_size: -1;
464
465 bytestream2_seek(gb, s->paldata_offset, SEEK_SET);
466 for (int n = 0; n < s->nb_pal; n++) {
467 ret = decode_palette(gb, s->pal + 16 * n);
468 if (ret < 0)
469 return ret;
470 }
471
472 if (s->tiledata_size > 0) {
473 ret = decode_tiledata(avctx);
474 if (ret < 0)
475 return ret;
476 }
477
478 if (s->palmapdata_size > 0) {
479 ret = decode_palmapdata(avctx);
480 if (ret < 0)
481 return ret;
482 }
483
484 if (s->palmapdata_size > 0 && s->tiledata_size > 0) {
485 ret = decode_index_palmap(s, frame);
486 if (ret < 0)
487 return ret;
488 } else if (s->tilemapdata_size > 0 && s->tiledata_size > 0) {
489 ret = decode_index_tilemap(s, frame);
490 if (ret < 0)
491 return ret;
492 } else if (s->tiledata_size > 0) {
493 ret = decode_index(s, frame);
494 if (ret < 0)
495 return ret;
496 }
497 break;
498 default:
499 av_log(avctx, AV_LOG_ERROR, "Unknown type: %X\n", type);
500 return AVERROR_INVALIDDATA;
501 }
502
503 memcpy(frame->data[1], s->pal, AVPALETTE_SIZE);
504 #if FF_API_PALETTE_HAS_CHANGED
505 FF_DISABLE_DEPRECATION_WARNINGS
506 frame->palette_has_changed = 1;
507 FF_ENABLE_DEPRECATION_WARNINGS
508 #endif
509 frame->pict_type = AV_PICTURE_TYPE_I;
510 frame->flags |= AV_FRAME_FLAG_KEY;
511
512 *got_frame = 1;
513
514 return avpkt->size;
515 }
516
517 static av_cold int sga_decode_end(AVCodecContext *avctx)
518 {
519 SGAVideoContext *s = avctx->priv_data;
520
521 av_freep(&s->tileindex_data);
522 s->tileindex_size = 0;
523
524 av_freep(&s->palmapindex_data);
525 s->palmapindex_size = 0;
526
527 return 0;
528 }
529
530 const FFCodec ff_sga_decoder = {
531 .p.name = "sga",
532 CODEC_LONG_NAME("Digital Pictures SGA Video"),
533 .p.type = AVMEDIA_TYPE_VIDEO,
534 .p.id = AV_CODEC_ID_SGA_VIDEO,
535 .priv_data_size = sizeof(SGAVideoContext),
536 .init = sga_decode_init,
537 FF_CODEC_DECODE_CB(sga_decode_frame),
538 .close = sga_decode_end,
539 .p.capabilities = AV_CODEC_CAP_DR1,
540 };
541