1 /*
2 * Chronomaster DFA Video Decoder
3 * Copyright (c) 2011 Konstantin Shishkov
4 * based on work by Vladimir "VAG" Gneushev
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 <inttypes.h>
24
25 #include "avcodec.h"
26 #include "bytestream.h"
27 #include "internal.h"
28
29 #include "libavutil/avassert.h"
30 #include "libavutil/imgutils.h"
31 #include "libavutil/mem.h"
32
33 typedef struct DfaContext {
34 uint32_t pal[256];
35 uint8_t *frame_buf;
36 } DfaContext;
37
dfa_decode_init(AVCodecContext * avctx)38 static av_cold int dfa_decode_init(AVCodecContext *avctx)
39 {
40 DfaContext *s = avctx->priv_data;
41
42 avctx->pix_fmt = AV_PIX_FMT_PAL8;
43
44 if (!avctx->width || !avctx->height || FFMAX(avctx->width, avctx->height) >= (1<<16))
45 return AVERROR_INVALIDDATA;
46
47 av_assert0(av_image_check_size(avctx->width, avctx->height, 0, avctx) >= 0);
48
49 s->frame_buf = av_mallocz(avctx->width * avctx->height);
50 if (!s->frame_buf)
51 return AVERROR(ENOMEM);
52
53 return 0;
54 }
55
decode_copy(GetByteContext * gb,uint8_t * frame,int width,int height)56 static int decode_copy(GetByteContext *gb, uint8_t *frame, int width, int height)
57 {
58 const int size = width * height;
59
60 if (bytestream2_get_buffer(gb, frame, size) != size)
61 return AVERROR_INVALIDDATA;
62 return 0;
63 }
64
decode_tsw1(GetByteContext * gb,uint8_t * frame,int width,int height)65 static int decode_tsw1(GetByteContext *gb, uint8_t *frame, int width, int height)
66 {
67 const uint8_t *frame_start = frame;
68 const uint8_t *frame_end = frame + width * height;
69 int mask = 0x10000, bitbuf = 0;
70 int v, count;
71 unsigned segments;
72 unsigned offset;
73
74 segments = bytestream2_get_le32(gb);
75 offset = bytestream2_get_le32(gb);
76 if (segments == 0 && offset == frame_end - frame)
77 return 0; // skip frame
78 if (frame_end - frame <= offset)
79 return AVERROR_INVALIDDATA;
80 frame += offset;
81 while (segments--) {
82 if (bytestream2_get_bytes_left(gb) < 2)
83 return AVERROR_INVALIDDATA;
84 if (mask == 0x10000) {
85 bitbuf = bytestream2_get_le16u(gb);
86 mask = 1;
87 }
88 if (frame_end - frame < 2)
89 return AVERROR_INVALIDDATA;
90 if (bitbuf & mask) {
91 v = bytestream2_get_le16(gb);
92 offset = (v & 0x1FFF) << 1;
93 count = ((v >> 13) + 2) << 1;
94 if (frame - frame_start < offset || frame_end - frame < count)
95 return AVERROR_INVALIDDATA;
96 av_memcpy_backptr(frame, offset, count);
97 frame += count;
98 } else {
99 *frame++ = bytestream2_get_byte(gb);
100 *frame++ = bytestream2_get_byte(gb);
101 }
102 mask <<= 1;
103 }
104
105 return 0;
106 }
107
decode_dsw1(GetByteContext * gb,uint8_t * frame,int width,int height)108 static int decode_dsw1(GetByteContext *gb, uint8_t *frame, int width, int height)
109 {
110 const uint8_t *frame_start = frame;
111 const uint8_t *frame_end = frame + width * height;
112 int mask = 0x10000, bitbuf = 0;
113 int v, offset, count, segments;
114
115 segments = bytestream2_get_le16(gb);
116 while (segments--) {
117 if (bytestream2_get_bytes_left(gb) < 2)
118 return AVERROR_INVALIDDATA;
119 if (mask == 0x10000) {
120 bitbuf = bytestream2_get_le16u(gb);
121 mask = 1;
122 }
123 if (frame_end - frame < 2)
124 return AVERROR_INVALIDDATA;
125 if (bitbuf & mask) {
126 v = bytestream2_get_le16(gb);
127 offset = (v & 0x1FFF) << 1;
128 count = ((v >> 13) + 2) << 1;
129 if (frame - frame_start < offset || frame_end - frame < count)
130 return AVERROR_INVALIDDATA;
131 av_memcpy_backptr(frame, offset, count);
132 frame += count;
133 } else if (bitbuf & (mask << 1)) {
134 frame += bytestream2_get_le16(gb);
135 } else {
136 *frame++ = bytestream2_get_byte(gb);
137 *frame++ = bytestream2_get_byte(gb);
138 }
139 mask <<= 2;
140 }
141
142 return 0;
143 }
144
decode_dds1(GetByteContext * gb,uint8_t * frame,int width,int height)145 static int decode_dds1(GetByteContext *gb, uint8_t *frame, int width, int height)
146 {
147 const uint8_t *frame_start = frame;
148 const uint8_t *frame_end = frame + width * height;
149 int mask = 0x10000, bitbuf = 0;
150 int i, v, offset, count, segments;
151
152 if ((width | height) & 1)
153 return AVERROR_INVALIDDATA;
154 segments = bytestream2_get_le16(gb);
155 while (segments--) {
156 if (bytestream2_get_bytes_left(gb) < 2)
157 return AVERROR_INVALIDDATA;
158 if (mask == 0x10000) {
159 bitbuf = bytestream2_get_le16u(gb);
160 mask = 1;
161 }
162
163 if (bitbuf & mask) {
164 v = bytestream2_get_le16(gb);
165 offset = (v & 0x1FFF) << 2;
166 count = ((v >> 13) + 2) << 1;
167 if (frame - frame_start < offset || frame_end - frame < count*2 + width)
168 return AVERROR_INVALIDDATA;
169 for (i = 0; i < count; i++) {
170 frame[0] = frame[1] =
171 frame[width] = frame[width + 1] = frame[-offset];
172
173 frame += 2;
174 }
175 } else if (bitbuf & (mask << 1)) {
176 v = bytestream2_get_le16(gb)*2;
177 if (frame - frame_end < v)
178 return AVERROR_INVALIDDATA;
179 frame += v;
180 } else {
181 if (width < 4 || frame_end - frame < width + 4)
182 return AVERROR_INVALIDDATA;
183 frame[0] = frame[1] =
184 frame[width] = frame[width + 1] = bytestream2_get_byte(gb);
185 frame += 2;
186 frame[0] = frame[1] =
187 frame[width] = frame[width + 1] = bytestream2_get_byte(gb);
188 frame += 2;
189 }
190 mask <<= 2;
191 }
192
193 return 0;
194 }
195
decode_bdlt(GetByteContext * gb,uint8_t * frame,int width,int height)196 static int decode_bdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
197 {
198 uint8_t *line_ptr;
199 int count, lines, segments;
200
201 count = bytestream2_get_le16(gb);
202 if (count >= height)
203 return AVERROR_INVALIDDATA;
204 frame += width * count;
205 lines = bytestream2_get_le16(gb);
206 if (count + lines > height)
207 return AVERROR_INVALIDDATA;
208
209 while (lines--) {
210 if (bytestream2_get_bytes_left(gb) < 1)
211 return AVERROR_INVALIDDATA;
212 line_ptr = frame;
213 frame += width;
214 segments = bytestream2_get_byteu(gb);
215 while (segments--) {
216 if (frame - line_ptr <= bytestream2_peek_byte(gb))
217 return AVERROR_INVALIDDATA;
218 line_ptr += bytestream2_get_byte(gb);
219 count = (int8_t)bytestream2_get_byte(gb);
220 if (count >= 0) {
221 if (frame - line_ptr < count)
222 return AVERROR_INVALIDDATA;
223 if (bytestream2_get_buffer(gb, line_ptr, count) != count)
224 return AVERROR_INVALIDDATA;
225 } else {
226 count = -count;
227 if (frame - line_ptr < count)
228 return AVERROR_INVALIDDATA;
229 memset(line_ptr, bytestream2_get_byte(gb), count);
230 }
231 line_ptr += count;
232 }
233 }
234
235 return 0;
236 }
237
decode_wdlt(GetByteContext * gb,uint8_t * frame,int width,int height)238 static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
239 {
240 const uint8_t *frame_end = frame + width * height;
241 uint8_t *line_ptr;
242 int count, i, v, lines, segments;
243 int y = 0;
244
245 lines = bytestream2_get_le16(gb);
246 if (lines > height)
247 return AVERROR_INVALIDDATA;
248
249 while (lines--) {
250 if (bytestream2_get_bytes_left(gb) < 2)
251 return AVERROR_INVALIDDATA;
252 segments = bytestream2_get_le16u(gb);
253 while ((segments & 0xC000) == 0xC000) {
254 unsigned skip_lines = -(int16_t)segments;
255 int64_t delta = -((int16_t)segments * (int64_t)width);
256 if (frame_end - frame <= delta || y + lines + skip_lines > height)
257 return AVERROR_INVALIDDATA;
258 frame += delta;
259 y += skip_lines;
260 segments = bytestream2_get_le16(gb);
261 }
262
263 if (frame_end <= frame)
264 return AVERROR_INVALIDDATA;
265 if (segments & 0x8000) {
266 frame[width - 1] = segments & 0xFF;
267 segments = bytestream2_get_le16(gb);
268 }
269 line_ptr = frame;
270 if (frame_end - frame < width)
271 return AVERROR_INVALIDDATA;
272 frame += width;
273 y++;
274 while (segments--) {
275 if (frame - line_ptr <= bytestream2_peek_byte(gb))
276 return AVERROR_INVALIDDATA;
277 line_ptr += bytestream2_get_byte(gb);
278 count = (int8_t)bytestream2_get_byte(gb);
279 if (count >= 0) {
280 if (frame - line_ptr < count * 2)
281 return AVERROR_INVALIDDATA;
282 if (bytestream2_get_buffer(gb, line_ptr, count * 2) != count * 2)
283 return AVERROR_INVALIDDATA;
284 line_ptr += count * 2;
285 } else {
286 count = -count;
287 if (frame - line_ptr < count * 2)
288 return AVERROR_INVALIDDATA;
289 v = bytestream2_get_le16(gb);
290 for (i = 0; i < count; i++)
291 bytestream_put_le16(&line_ptr, v);
292 }
293 }
294 }
295
296 return 0;
297 }
298
decode_tdlt(GetByteContext * gb,uint8_t * frame,int width,int height)299 static int decode_tdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
300 {
301 const uint8_t *frame_end = frame + width * height;
302 uint32_t segments = bytestream2_get_le32(gb);
303 int skip, copy;
304
305 while (segments--) {
306 if (bytestream2_get_bytes_left(gb) < 2)
307 return AVERROR_INVALIDDATA;
308 copy = bytestream2_get_byteu(gb) * 2;
309 skip = bytestream2_get_byteu(gb) * 2;
310 if (frame_end - frame < copy + skip ||
311 bytestream2_get_bytes_left(gb) < copy)
312 return AVERROR_INVALIDDATA;
313 frame += skip;
314 bytestream2_get_buffer(gb, frame, copy);
315 frame += copy;
316 }
317
318 return 0;
319 }
320
decode_blck(GetByteContext * gb,uint8_t * frame,int width,int height)321 static int decode_blck(GetByteContext *gb, uint8_t *frame, int width, int height)
322 {
323 memset(frame, 0, width * height);
324 return 0;
325 }
326
327
328 typedef int (*chunk_decoder)(GetByteContext *gb, uint8_t *frame, int width, int height);
329
330 static const chunk_decoder decoder[8] = {
331 decode_copy, decode_tsw1, decode_bdlt, decode_wdlt,
332 decode_tdlt, decode_dsw1, decode_blck, decode_dds1,
333 };
334
335 static const char chunk_name[8][5] = {
336 "COPY", "TSW1", "BDLT", "WDLT", "TDLT", "DSW1", "BLCK", "DDS1"
337 };
338
dfa_decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)339 static int dfa_decode_frame(AVCodecContext *avctx,
340 void *data, int *got_frame,
341 AVPacket *avpkt)
342 {
343 AVFrame *frame = data;
344 DfaContext *s = avctx->priv_data;
345 GetByteContext gb;
346 const uint8_t *buf = avpkt->data;
347 uint32_t chunk_type, chunk_size;
348 uint8_t *dst;
349 int ret;
350 int i, pal_elems;
351 int version = avctx->extradata_size==2 ? AV_RL16(avctx->extradata) : 0;
352
353 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
354 return ret;
355
356 bytestream2_init(&gb, avpkt->data, avpkt->size);
357 while (bytestream2_get_bytes_left(&gb) > 0) {
358 if (bytestream2_get_bytes_left(&gb) < 12)
359 return AVERROR_INVALIDDATA;
360 bytestream2_skip(&gb, 4);
361 chunk_size = bytestream2_get_le32(&gb);
362 chunk_type = bytestream2_get_le32(&gb);
363 if (!chunk_type)
364 break;
365 if (chunk_type == 1) {
366 pal_elems = FFMIN(chunk_size / 3, 256);
367 for (i = 0; i < pal_elems; i++) {
368 s->pal[i] = bytestream2_get_be24(&gb) << 2;
369 s->pal[i] |= 0xFFU << 24 | (s->pal[i] >> 6) & 0x30303;
370 }
371 frame->palette_has_changed = 1;
372 } else if (chunk_type <= 9) {
373 if (decoder[chunk_type - 2](&gb, s->frame_buf, avctx->width, avctx->height)) {
374 av_log(avctx, AV_LOG_ERROR, "Error decoding %s chunk\n",
375 chunk_name[chunk_type - 2]);
376 return AVERROR_INVALIDDATA;
377 }
378 } else {
379 av_log(avctx, AV_LOG_WARNING,
380 "Ignoring unknown chunk type %"PRIu32"\n",
381 chunk_type);
382 }
383 buf += chunk_size;
384 }
385
386 buf = s->frame_buf;
387 dst = frame->data[0];
388 for (i = 0; i < avctx->height; i++) {
389 if(version == 0x100) {
390 int j;
391 for(j = 0; j < avctx->width; j++) {
392 dst[j] = buf[ (i&3)*(avctx->width /4) + (j/4) +
393 ((j&3)*(avctx->height/4) + (i/4))*avctx->width];
394 }
395 } else {
396 memcpy(dst, buf, avctx->width);
397 buf += avctx->width;
398 }
399 dst += frame->linesize[0];
400 }
401 memcpy(frame->data[1], s->pal, sizeof(s->pal));
402
403 *got_frame = 1;
404
405 return avpkt->size;
406 }
407
dfa_decode_end(AVCodecContext * avctx)408 static av_cold int dfa_decode_end(AVCodecContext *avctx)
409 {
410 DfaContext *s = avctx->priv_data;
411
412 av_freep(&s->frame_buf);
413
414 return 0;
415 }
416
417 AVCodec ff_dfa_decoder = {
418 .name = "dfa",
419 .long_name = NULL_IF_CONFIG_SMALL("Chronomaster DFA"),
420 .type = AVMEDIA_TYPE_VIDEO,
421 .id = AV_CODEC_ID_DFA,
422 .priv_data_size = sizeof(DfaContext),
423 .init = dfa_decode_init,
424 .close = dfa_decode_end,
425 .decode = dfa_decode_frame,
426 .capabilities = AV_CODEC_CAP_DR1,
427 };
428