1 /*
2 * Sierra VMD video decoder
3 * Copyright (c) 2004 The FFmpeg Project
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * Sierra VMD video decoder
25 * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
26 * for more information on the Sierra VMD format, visit:
27 * http://www.pcisys.net/~melanson/codecs/
28 *
29 * The video decoder outputs PAL8 colorspace data. The decoder expects
30 * a 0x330-byte VMD file header to be transmitted via extradata during
31 * codec initialization. Each encoded frame that is sent to this decoder
32 * is expected to be prepended with the appropriate 16-byte frame
33 * information record from the VMD file.
34 */
35
36 #include <string.h>
37
38 #include "libavutil/common.h"
39 #include "libavutil/intreadwrite.h"
40
41 #include "avcodec.h"
42 #include "codec_internal.h"
43 #include "internal.h"
44 #include "bytestream.h"
45
46 #define VMD_HEADER_SIZE 0x330
47 #define PALETTE_COUNT 256
48
49 typedef struct VmdVideoContext {
50
51 AVCodecContext *avctx;
52 AVFrame *prev_frame;
53
54 const unsigned char *buf;
55 int size;
56
57 unsigned char palette[PALETTE_COUNT * 4];
58 unsigned char *unpack_buffer;
59 int unpack_buffer_size;
60
61 int x_off, y_off;
62 } VmdVideoContext;
63
64 #define QUEUE_SIZE 0x1000
65 #define QUEUE_MASK 0x0FFF
66
lz_unpack(const unsigned char * src,int src_len,unsigned char * dest,int dest_len)67 static int lz_unpack(const unsigned char *src, int src_len,
68 unsigned char *dest, int dest_len)
69 {
70 unsigned char *d;
71 unsigned char *d_end;
72 unsigned char queue[QUEUE_SIZE];
73 unsigned int qpos;
74 unsigned int dataleft;
75 unsigned int chainofs;
76 unsigned int chainlen;
77 unsigned int speclen;
78 unsigned char tag;
79 unsigned int i, j;
80 GetByteContext gb;
81
82 bytestream2_init(&gb, src, src_len);
83 d = dest;
84 d_end = d + dest_len;
85 dataleft = bytestream2_get_le32(&gb);
86 memset(queue, 0x20, QUEUE_SIZE);
87 if (bytestream2_get_bytes_left(&gb) < 4)
88 return AVERROR_INVALIDDATA;
89 if (bytestream2_peek_le32(&gb) == 0x56781234) {
90 bytestream2_skipu(&gb, 4);
91 qpos = 0x111;
92 speclen = 0xF + 3;
93 } else {
94 qpos = 0xFEE;
95 speclen = 100; /* no speclen */
96 }
97
98 while (dataleft > 0 && bytestream2_get_bytes_left(&gb) > 0) {
99 tag = bytestream2_get_byteu(&gb);
100 if ((tag == 0xFF) && (dataleft > 8)) {
101 if (d_end - d < 8 || bytestream2_get_bytes_left(&gb) < 8)
102 return AVERROR_INVALIDDATA;
103 for (i = 0; i < 8; i++) {
104 queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
105 qpos &= QUEUE_MASK;
106 }
107 dataleft -= 8;
108 } else {
109 for (i = 0; i < 8; i++) {
110 if (dataleft == 0)
111 break;
112 if (tag & 0x01) {
113 if (d_end - d < 1 || bytestream2_get_bytes_left(&gb) < 1)
114 return AVERROR_INVALIDDATA;
115 queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
116 qpos &= QUEUE_MASK;
117 dataleft--;
118 } else {
119 chainofs = bytestream2_get_byte(&gb);
120 chainofs |= ((bytestream2_peek_byte(&gb) & 0xF0) << 4);
121 chainlen = (bytestream2_get_byte(&gb) & 0x0F) + 3;
122 if (chainlen == speclen) {
123 chainlen = bytestream2_get_byte(&gb) + 0xF + 3;
124 }
125 if (d_end - d < chainlen)
126 return AVERROR_INVALIDDATA;
127 for (j = 0; j < chainlen; j++) {
128 *d = queue[chainofs++ & QUEUE_MASK];
129 queue[qpos++] = *d++;
130 qpos &= QUEUE_MASK;
131 }
132 dataleft -= chainlen;
133 }
134 tag >>= 1;
135 }
136 }
137 }
138 return d - dest;
139 }
rle_unpack(const unsigned char * src,unsigned char * dest,int src_count,int src_size,int dest_len)140 static int rle_unpack(const unsigned char *src, unsigned char *dest,
141 int src_count, int src_size, int dest_len)
142 {
143 unsigned char *pd;
144 int i, l, used = 0;
145 unsigned char *dest_end = dest + dest_len;
146 GetByteContext gb;
147 uint16_t run_val;
148
149 bytestream2_init(&gb, src, src_size);
150 pd = dest;
151 if (src_count & 1) {
152 if (bytestream2_get_bytes_left(&gb) < 1)
153 return 0;
154 *pd++ = bytestream2_get_byteu(&gb);
155 used++;
156 }
157
158 do {
159 if (bytestream2_get_bytes_left(&gb) < 1)
160 break;
161 l = bytestream2_get_byteu(&gb);
162 if (l & 0x80) {
163 l = (l & 0x7F) * 2;
164 if (dest_end - pd < l || bytestream2_get_bytes_left(&gb) < l)
165 return bytestream2_tell(&gb);
166 bytestream2_get_bufferu(&gb, pd, l);
167 pd += l;
168 } else {
169 if (dest_end - pd < 2*l || bytestream2_get_bytes_left(&gb) < 2)
170 return bytestream2_tell(&gb);
171 run_val = bytestream2_get_ne16(&gb);
172 for (i = 0; i < l; i++) {
173 AV_WN16(pd, run_val);
174 pd += 2;
175 }
176 l *= 2;
177 }
178 used += l;
179 } while (used < src_count);
180
181 return bytestream2_tell(&gb);
182 }
183
vmd_decode(VmdVideoContext * s,AVFrame * frame)184 static int vmd_decode(VmdVideoContext *s, AVFrame *frame)
185 {
186 int i;
187 unsigned int *palette32;
188 unsigned char r, g, b;
189
190 GetByteContext gb;
191
192 unsigned char meth;
193 unsigned char *dp; /* pointer to current frame */
194 unsigned char *pp; /* pointer to previous frame */
195 unsigned char len;
196 int ofs;
197
198 int frame_x, frame_y, prev_linesize;
199 int frame_width, frame_height;
200
201 frame_x = AV_RL16(&s->buf[6]);
202 frame_y = AV_RL16(&s->buf[8]);
203 frame_width = AV_RL16(&s->buf[10]) - frame_x + 1;
204 frame_height = AV_RL16(&s->buf[12]) - frame_y + 1;
205
206 if ((frame_width == s->avctx->width && frame_height == s->avctx->height) &&
207 (frame_x || frame_y)) {
208
209 s->x_off = frame_x;
210 s->y_off = frame_y;
211 }
212 frame_x -= s->x_off;
213 frame_y -= s->y_off;
214
215 if (frame_x < 0 || frame_width < 0 ||
216 frame_x >= s->avctx->width ||
217 frame_width > s->avctx->width ||
218 frame_x + frame_width > s->avctx->width) {
219 av_log(s->avctx, AV_LOG_ERROR,
220 "Invalid horizontal range %d-%d\n",
221 frame_x, frame_width);
222 return AVERROR_INVALIDDATA;
223 }
224 if (frame_y < 0 || frame_height < 0 ||
225 frame_y >= s->avctx->height ||
226 frame_height > s->avctx->height ||
227 frame_y + frame_height > s->avctx->height) {
228 av_log(s->avctx, AV_LOG_ERROR,
229 "Invalid vertical range %d-%d\n",
230 frame_y, frame_height);
231 return AVERROR_INVALIDDATA;
232 }
233
234 /* if only a certain region will be updated, copy the entire previous
235 * frame before the decode */
236 if (s->prev_frame->data[0] &&
237 (frame_x || frame_y || (frame_width != s->avctx->width) ||
238 (frame_height != s->avctx->height))) {
239
240 memcpy(frame->data[0], s->prev_frame->data[0],
241 s->avctx->height * frame->linesize[0]);
242 }
243
244 /* check if there is a new palette */
245 bytestream2_init(&gb, s->buf + 16, s->size - 16);
246 if (s->buf[15] & 0x02) {
247 bytestream2_skip(&gb, 2);
248 palette32 = (unsigned int *)s->palette;
249 if (bytestream2_get_bytes_left(&gb) >= PALETTE_COUNT * 3) {
250 for (i = 0; i < PALETTE_COUNT; i++) {
251 r = bytestream2_get_byteu(&gb) * 4;
252 g = bytestream2_get_byteu(&gb) * 4;
253 b = bytestream2_get_byteu(&gb) * 4;
254 palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
255 palette32[i] |= palette32[i] >> 6 & 0x30303;
256 }
257 } else {
258 av_log(s->avctx, AV_LOG_ERROR, "Incomplete palette\n");
259 return AVERROR_INVALIDDATA;
260 }
261 }
262
263 if (!s->size)
264 return 0;
265
266 /* originally UnpackFrame in VAG's code */
267 if (bytestream2_get_bytes_left(&gb) < 1)
268 return AVERROR_INVALIDDATA;
269 meth = bytestream2_get_byteu(&gb);
270 if (meth & 0x80) {
271 int size;
272 if (!s->unpack_buffer_size) {
273 av_log(s->avctx, AV_LOG_ERROR,
274 "Trying to unpack LZ-compressed frame with no LZ buffer\n");
275 return AVERROR_INVALIDDATA;
276 }
277 size = lz_unpack(gb.buffer, bytestream2_get_bytes_left(&gb),
278 s->unpack_buffer, s->unpack_buffer_size);
279 if (size < 0)
280 return size;
281 meth &= 0x7F;
282 bytestream2_init(&gb, s->unpack_buffer, size);
283 }
284
285 dp = &frame->data[0][frame_y * frame->linesize[0] + frame_x];
286 if (s->prev_frame->data[0]) {
287 prev_linesize = s->prev_frame->linesize[0];
288 pp = s->prev_frame->data[0] + frame_y * prev_linesize + frame_x;
289 } else {
290 pp = NULL;
291 prev_linesize = 0;
292 }
293 switch (meth) {
294 case 1:
295 for (i = 0; i < frame_height; i++) {
296 ofs = 0;
297 do {
298 len = bytestream2_get_byte(&gb);
299 if (len & 0x80) {
300 len = (len & 0x7F) + 1;
301 if (ofs + len > frame_width ||
302 bytestream2_get_bytes_left(&gb) < len)
303 return AVERROR_INVALIDDATA;
304 bytestream2_get_bufferu(&gb, &dp[ofs], len);
305 ofs += len;
306 } else {
307 /* interframe pixel copy */
308 if (ofs + len + 1 > frame_width || !pp)
309 return AVERROR_INVALIDDATA;
310 memcpy(&dp[ofs], &pp[ofs], len + 1);
311 ofs += len + 1;
312 }
313 } while (ofs < frame_width);
314 if (ofs > frame_width) {
315 av_log(s->avctx, AV_LOG_ERROR,
316 "offset > width (%d > %d)\n",
317 ofs, frame_width);
318 return AVERROR_INVALIDDATA;
319 }
320 dp += frame->linesize[0];
321 pp = FF_PTR_ADD(pp, prev_linesize);
322 }
323 break;
324
325 case 2:
326 for (i = 0; i < frame_height; i++) {
327 bytestream2_get_buffer(&gb, dp, frame_width);
328 dp += frame->linesize[0];
329 }
330 break;
331
332 case 3:
333 for (i = 0; i < frame_height; i++) {
334 ofs = 0;
335 do {
336 len = bytestream2_get_byte(&gb);
337 if (len & 0x80) {
338 len = (len & 0x7F) + 1;
339 if (bytestream2_peek_byte(&gb) == 0xFF) {
340 int slen = len;
341 bytestream2_get_byte(&gb);
342 len = rle_unpack(gb.buffer, &dp[ofs],
343 len, bytestream2_get_bytes_left(&gb),
344 frame_width - ofs);
345 ofs += slen;
346 bytestream2_skip(&gb, len);
347 } else {
348 if (ofs + len > frame_width ||
349 bytestream2_get_bytes_left(&gb) < len)
350 return AVERROR_INVALIDDATA;
351 bytestream2_get_buffer(&gb, &dp[ofs], len);
352 ofs += len;
353 }
354 } else {
355 /* interframe pixel copy */
356 if (ofs + len + 1 > frame_width || !pp)
357 return AVERROR_INVALIDDATA;
358 memcpy(&dp[ofs], &pp[ofs], len + 1);
359 ofs += len + 1;
360 }
361 } while (ofs < frame_width);
362 if (ofs > frame_width) {
363 av_log(s->avctx, AV_LOG_ERROR,
364 "offset > width (%d > %d)\n",
365 ofs, frame_width);
366 return AVERROR_INVALIDDATA;
367 }
368 dp += frame->linesize[0];
369 pp = FF_PTR_ADD(pp, prev_linesize);
370 }
371 break;
372 }
373 return 0;
374 }
375
vmdvideo_decode_end(AVCodecContext * avctx)376 static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
377 {
378 VmdVideoContext *s = avctx->priv_data;
379
380 av_frame_free(&s->prev_frame);
381 av_freep(&s->unpack_buffer);
382 s->unpack_buffer_size = 0;
383
384 return 0;
385 }
386
vmdvideo_decode_init(AVCodecContext * avctx)387 static av_cold int vmdvideo_decode_init(AVCodecContext *avctx)
388 {
389 VmdVideoContext *s = avctx->priv_data;
390 int i;
391 unsigned int *palette32;
392 int palette_index = 0;
393 unsigned char r, g, b;
394 unsigned char *vmd_header;
395 unsigned char *raw_palette;
396
397 s->avctx = avctx;
398 avctx->pix_fmt = AV_PIX_FMT_PAL8;
399
400 /* make sure the VMD header made it */
401 if (s->avctx->extradata_size != VMD_HEADER_SIZE) {
402 av_log(s->avctx, AV_LOG_ERROR, "expected extradata size of %d\n",
403 VMD_HEADER_SIZE);
404 return AVERROR_INVALIDDATA;
405 }
406 vmd_header = (unsigned char *)avctx->extradata;
407
408 s->unpack_buffer_size = AV_RL32(&vmd_header[800]);
409 if (s->unpack_buffer_size) {
410 s->unpack_buffer = av_malloc(s->unpack_buffer_size);
411 if (!s->unpack_buffer)
412 return AVERROR(ENOMEM);
413 }
414
415 /* load up the initial palette */
416 raw_palette = &vmd_header[28];
417 palette32 = (unsigned int *)s->palette;
418 for (i = 0; i < PALETTE_COUNT; i++) {
419 r = raw_palette[palette_index++] * 4;
420 g = raw_palette[palette_index++] * 4;
421 b = raw_palette[palette_index++] * 4;
422 palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
423 palette32[i] |= palette32[i] >> 6 & 0x30303;
424 }
425
426 s->prev_frame = av_frame_alloc();
427 if (!s->prev_frame)
428 return AVERROR(ENOMEM);
429
430 return 0;
431 }
432
vmdvideo_decode_frame(AVCodecContext * avctx,AVFrame * frame,int * got_frame,AVPacket * avpkt)433 static int vmdvideo_decode_frame(AVCodecContext *avctx, AVFrame *frame,
434 int *got_frame, AVPacket *avpkt)
435 {
436 const uint8_t *buf = avpkt->data;
437 int buf_size = avpkt->size;
438 VmdVideoContext *s = avctx->priv_data;
439 int ret;
440
441 s->buf = buf;
442 s->size = buf_size;
443
444 if (buf_size < 16)
445 return AVERROR_INVALIDDATA;
446
447 if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
448 return ret;
449
450 if ((ret = vmd_decode(s, frame)) < 0)
451 return ret;
452
453 /* make the palette available on the way out */
454 memcpy(frame->data[1], s->palette, PALETTE_COUNT * 4);
455
456 /* shuffle frames */
457 av_frame_unref(s->prev_frame);
458 if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
459 return ret;
460
461 *got_frame = 1;
462
463 /* report that the buffer was completely consumed */
464 return buf_size;
465 }
466
467 const FFCodec ff_vmdvideo_decoder = {
468 .p.name = "vmdvideo",
469 .p.long_name = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
470 .p.type = AVMEDIA_TYPE_VIDEO,
471 .p.id = AV_CODEC_ID_VMDVIDEO,
472 .priv_data_size = sizeof(VmdVideoContext),
473 .init = vmdvideo_decode_init,
474 .close = vmdvideo_decode_end,
475 FF_CODEC_DECODE_CB(vmdvideo_decode_frame),
476 .p.capabilities = AV_CODEC_CAP_DR1,
477 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
478 };
479