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 "internal.h"
43 #include "bytestream.h"
44
45 #define VMD_HEADER_SIZE 0x330
46 #define PALETTE_COUNT 256
47
48 typedef struct VmdVideoContext {
49
50 AVCodecContext *avctx;
51 AVFrame *prev_frame;
52
53 const unsigned char *buf;
54 int size;
55
56 unsigned char palette[PALETTE_COUNT * 4];
57 unsigned char *unpack_buffer;
58 int unpack_buffer_size;
59
60 int x_off, y_off;
61 } VmdVideoContext;
62
63 #define QUEUE_SIZE 0x1000
64 #define QUEUE_MASK 0x0FFF
65
lz_unpack(const unsigned char * src,int src_len,unsigned char * dest,int dest_len)66 static int lz_unpack(const unsigned char *src, int src_len,
67 unsigned char *dest, int dest_len)
68 {
69 unsigned char *d;
70 unsigned char *d_end;
71 unsigned char queue[QUEUE_SIZE];
72 unsigned int qpos;
73 unsigned int dataleft;
74 unsigned int chainofs;
75 unsigned int chainlen;
76 unsigned int speclen;
77 unsigned char tag;
78 unsigned int i, j;
79 GetByteContext gb;
80
81 bytestream2_init(&gb, src, src_len);
82 d = dest;
83 d_end = d + dest_len;
84 dataleft = bytestream2_get_le32(&gb);
85 memset(queue, 0x20, QUEUE_SIZE);
86 if (bytestream2_get_bytes_left(&gb) < 4)
87 return AVERROR_INVALIDDATA;
88 if (bytestream2_peek_le32(&gb) == 0x56781234) {
89 bytestream2_skipu(&gb, 4);
90 qpos = 0x111;
91 speclen = 0xF + 3;
92 } else {
93 qpos = 0xFEE;
94 speclen = 100; /* no speclen */
95 }
96
97 while (dataleft > 0 && bytestream2_get_bytes_left(&gb) > 0) {
98 tag = bytestream2_get_byteu(&gb);
99 if ((tag == 0xFF) && (dataleft > 8)) {
100 if (d_end - d < 8 || bytestream2_get_bytes_left(&gb) < 8)
101 return AVERROR_INVALIDDATA;
102 for (i = 0; i < 8; i++) {
103 queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
104 qpos &= QUEUE_MASK;
105 }
106 dataleft -= 8;
107 } else {
108 for (i = 0; i < 8; i++) {
109 if (dataleft == 0)
110 break;
111 if (tag & 0x01) {
112 if (d_end - d < 1 || bytestream2_get_bytes_left(&gb) < 1)
113 return AVERROR_INVALIDDATA;
114 queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
115 qpos &= QUEUE_MASK;
116 dataleft--;
117 } else {
118 chainofs = bytestream2_get_byte(&gb);
119 chainofs |= ((bytestream2_peek_byte(&gb) & 0xF0) << 4);
120 chainlen = (bytestream2_get_byte(&gb) & 0x0F) + 3;
121 if (chainlen == speclen) {
122 chainlen = bytestream2_get_byte(&gb) + 0xF + 3;
123 }
124 if (d_end - d < chainlen)
125 return AVERROR_INVALIDDATA;
126 for (j = 0; j < chainlen; j++) {
127 *d = queue[chainofs++ & QUEUE_MASK];
128 queue[qpos++] = *d++;
129 qpos &= QUEUE_MASK;
130 }
131 dataleft -= chainlen;
132 }
133 tag >>= 1;
134 }
135 }
136 }
137 return d - dest;
138 }
rle_unpack(const unsigned char * src,unsigned char * dest,int src_count,int src_size,int dest_len)139 static int rle_unpack(const unsigned char *src, unsigned char *dest,
140 int src_count, int src_size, int dest_len)
141 {
142 unsigned char *pd;
143 int i, l, used = 0;
144 unsigned char *dest_end = dest + dest_len;
145 GetByteContext gb;
146 uint16_t run_val;
147
148 bytestream2_init(&gb, src, src_size);
149 pd = dest;
150 if (src_count & 1) {
151 if (bytestream2_get_bytes_left(&gb) < 1)
152 return 0;
153 *pd++ = bytestream2_get_byteu(&gb);
154 used++;
155 }
156
157 do {
158 if (bytestream2_get_bytes_left(&gb) < 1)
159 break;
160 l = bytestream2_get_byteu(&gb);
161 if (l & 0x80) {
162 l = (l & 0x7F) * 2;
163 if (dest_end - pd < l || bytestream2_get_bytes_left(&gb) < l)
164 return bytestream2_tell(&gb);
165 bytestream2_get_bufferu(&gb, pd, l);
166 pd += l;
167 } else {
168 if (dest_end - pd < 2*l || bytestream2_get_bytes_left(&gb) < 2)
169 return bytestream2_tell(&gb);
170 run_val = bytestream2_get_ne16(&gb);
171 for (i = 0; i < l; i++) {
172 AV_WN16(pd, run_val);
173 pd += 2;
174 }
175 l *= 2;
176 }
177 used += l;
178 } while (used < src_count);
179
180 return bytestream2_tell(&gb);
181 }
182
vmd_decode(VmdVideoContext * s,AVFrame * frame)183 static int vmd_decode(VmdVideoContext *s, AVFrame *frame)
184 {
185 int i;
186 unsigned int *palette32;
187 unsigned char r, g, b;
188
189 GetByteContext gb;
190
191 unsigned char meth;
192 unsigned char *dp; /* pointer to current frame */
193 unsigned char *pp; /* pointer to previous frame */
194 unsigned char len;
195 int ofs;
196
197 int frame_x, frame_y, prev_linesize;
198 int frame_width, frame_height;
199
200 frame_x = AV_RL16(&s->buf[6]);
201 frame_y = AV_RL16(&s->buf[8]);
202 frame_width = AV_RL16(&s->buf[10]) - frame_x + 1;
203 frame_height = AV_RL16(&s->buf[12]) - frame_y + 1;
204
205 if ((frame_width == s->avctx->width && frame_height == s->avctx->height) &&
206 (frame_x || frame_y)) {
207
208 s->x_off = frame_x;
209 s->y_off = frame_y;
210 }
211 frame_x -= s->x_off;
212 frame_y -= s->y_off;
213
214 if (frame_x < 0 || frame_width < 0 ||
215 frame_x >= s->avctx->width ||
216 frame_width > s->avctx->width ||
217 frame_x + frame_width > s->avctx->width) {
218 av_log(s->avctx, AV_LOG_ERROR,
219 "Invalid horizontal range %d-%d\n",
220 frame_x, frame_width);
221 return AVERROR_INVALIDDATA;
222 }
223 if (frame_y < 0 || frame_height < 0 ||
224 frame_y >= s->avctx->height ||
225 frame_height > s->avctx->height ||
226 frame_y + frame_height > s->avctx->height) {
227 av_log(s->avctx, AV_LOG_ERROR,
228 "Invalid vertical range %d-%d\n",
229 frame_y, frame_height);
230 return AVERROR_INVALIDDATA;
231 }
232
233 /* if only a certain region will be updated, copy the entire previous
234 * frame before the decode */
235 if (s->prev_frame->data[0] &&
236 (frame_x || frame_y || (frame_width != s->avctx->width) ||
237 (frame_height != s->avctx->height))) {
238
239 memcpy(frame->data[0], s->prev_frame->data[0],
240 s->avctx->height * frame->linesize[0]);
241 }
242
243 /* check if there is a new palette */
244 bytestream2_init(&gb, s->buf + 16, s->size - 16);
245 if (s->buf[15] & 0x02) {
246 bytestream2_skip(&gb, 2);
247 palette32 = (unsigned int *)s->palette;
248 if (bytestream2_get_bytes_left(&gb) >= PALETTE_COUNT * 3) {
249 for (i = 0; i < PALETTE_COUNT; i++) {
250 r = bytestream2_get_byteu(&gb) * 4;
251 g = bytestream2_get_byteu(&gb) * 4;
252 b = bytestream2_get_byteu(&gb) * 4;
253 palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
254 palette32[i] |= palette32[i] >> 6 & 0x30303;
255 }
256 } else {
257 av_log(s->avctx, AV_LOG_ERROR, "Incomplete palette\n");
258 return AVERROR_INVALIDDATA;
259 }
260 }
261
262 if (!s->size)
263 return 0;
264
265 /* originally UnpackFrame in VAG's code */
266 if (bytestream2_get_bytes_left(&gb) < 1)
267 return AVERROR_INVALIDDATA;
268 meth = bytestream2_get_byteu(&gb);
269 if (meth & 0x80) {
270 int size;
271 if (!s->unpack_buffer_size) {
272 av_log(s->avctx, AV_LOG_ERROR,
273 "Trying to unpack LZ-compressed frame with no LZ buffer\n");
274 return AVERROR_INVALIDDATA;
275 }
276 size = lz_unpack(gb.buffer, bytestream2_get_bytes_left(&gb),
277 s->unpack_buffer, s->unpack_buffer_size);
278 if (size < 0)
279 return size;
280 meth &= 0x7F;
281 bytestream2_init(&gb, s->unpack_buffer, size);
282 }
283
284 dp = &frame->data[0][frame_y * frame->linesize[0] + frame_x];
285 if (s->prev_frame->data[0]) {
286 prev_linesize = s->prev_frame->linesize[0];
287 pp = s->prev_frame->data[0] + frame_y * prev_linesize + frame_x;
288 } else {
289 pp = NULL;
290 prev_linesize = 0;
291 }
292 switch (meth) {
293 case 1:
294 for (i = 0; i < frame_height; i++) {
295 ofs = 0;
296 do {
297 len = bytestream2_get_byte(&gb);
298 if (len & 0x80) {
299 len = (len & 0x7F) + 1;
300 if (ofs + len > frame_width ||
301 bytestream2_get_bytes_left(&gb) < len)
302 return AVERROR_INVALIDDATA;
303 bytestream2_get_bufferu(&gb, &dp[ofs], len);
304 ofs += len;
305 } else {
306 /* interframe pixel copy */
307 if (ofs + len + 1 > frame_width || !pp)
308 return AVERROR_INVALIDDATA;
309 memcpy(&dp[ofs], &pp[ofs], len + 1);
310 ofs += len + 1;
311 }
312 } while (ofs < frame_width);
313 if (ofs > frame_width) {
314 av_log(s->avctx, AV_LOG_ERROR,
315 "offset > width (%d > %d)\n",
316 ofs, frame_width);
317 return AVERROR_INVALIDDATA;
318 }
319 dp += frame->linesize[0];
320 pp = FF_PTR_ADD(pp, prev_linesize);
321 }
322 break;
323
324 case 2:
325 for (i = 0; i < frame_height; i++) {
326 bytestream2_get_buffer(&gb, dp, frame_width);
327 dp += frame->linesize[0];
328 }
329 break;
330
331 case 3:
332 for (i = 0; i < frame_height; i++) {
333 ofs = 0;
334 do {
335 len = bytestream2_get_byte(&gb);
336 if (len & 0x80) {
337 len = (len & 0x7F) + 1;
338 if (bytestream2_peek_byte(&gb) == 0xFF) {
339 int slen = len;
340 bytestream2_get_byte(&gb);
341 len = rle_unpack(gb.buffer, &dp[ofs],
342 len, bytestream2_get_bytes_left(&gb),
343 frame_width - ofs);
344 ofs += slen;
345 bytestream2_skip(&gb, len);
346 } else {
347 if (ofs + len > frame_width ||
348 bytestream2_get_bytes_left(&gb) < len)
349 return AVERROR_INVALIDDATA;
350 bytestream2_get_buffer(&gb, &dp[ofs], len);
351 ofs += len;
352 }
353 } else {
354 /* interframe pixel copy */
355 if (ofs + len + 1 > frame_width || !pp)
356 return AVERROR_INVALIDDATA;
357 memcpy(&dp[ofs], &pp[ofs], len + 1);
358 ofs += len + 1;
359 }
360 } while (ofs < frame_width);
361 if (ofs > frame_width) {
362 av_log(s->avctx, AV_LOG_ERROR,
363 "offset > width (%d > %d)\n",
364 ofs, frame_width);
365 return AVERROR_INVALIDDATA;
366 }
367 dp += frame->linesize[0];
368 pp = FF_PTR_ADD(pp, prev_linesize);
369 }
370 break;
371 }
372 return 0;
373 }
374
vmdvideo_decode_end(AVCodecContext * avctx)375 static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
376 {
377 VmdVideoContext *s = avctx->priv_data;
378
379 av_frame_free(&s->prev_frame);
380 av_freep(&s->unpack_buffer);
381 s->unpack_buffer_size = 0;
382
383 return 0;
384 }
385
vmdvideo_decode_init(AVCodecContext * avctx)386 static av_cold int vmdvideo_decode_init(AVCodecContext *avctx)
387 {
388 VmdVideoContext *s = avctx->priv_data;
389 int i;
390 unsigned int *palette32;
391 int palette_index = 0;
392 unsigned char r, g, b;
393 unsigned char *vmd_header;
394 unsigned char *raw_palette;
395
396 s->avctx = avctx;
397 avctx->pix_fmt = AV_PIX_FMT_PAL8;
398
399 /* make sure the VMD header made it */
400 if (s->avctx->extradata_size != VMD_HEADER_SIZE) {
401 av_log(s->avctx, AV_LOG_ERROR, "expected extradata size of %d\n",
402 VMD_HEADER_SIZE);
403 return AVERROR_INVALIDDATA;
404 }
405 vmd_header = (unsigned char *)avctx->extradata;
406
407 s->unpack_buffer_size = AV_RL32(&vmd_header[800]);
408 if (s->unpack_buffer_size) {
409 s->unpack_buffer = av_malloc(s->unpack_buffer_size);
410 if (!s->unpack_buffer)
411 return AVERROR(ENOMEM);
412 }
413
414 /* load up the initial palette */
415 raw_palette = &vmd_header[28];
416 palette32 = (unsigned int *)s->palette;
417 for (i = 0; i < PALETTE_COUNT; i++) {
418 r = raw_palette[palette_index++] * 4;
419 g = raw_palette[palette_index++] * 4;
420 b = raw_palette[palette_index++] * 4;
421 palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
422 palette32[i] |= palette32[i] >> 6 & 0x30303;
423 }
424
425 s->prev_frame = av_frame_alloc();
426 if (!s->prev_frame) {
427 vmdvideo_decode_end(avctx);
428 return AVERROR(ENOMEM);
429 }
430
431 return 0;
432 }
433
vmdvideo_decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)434 static int vmdvideo_decode_frame(AVCodecContext *avctx,
435 void *data, int *got_frame,
436 AVPacket *avpkt)
437 {
438 const uint8_t *buf = avpkt->data;
439 int buf_size = avpkt->size;
440 VmdVideoContext *s = avctx->priv_data;
441 AVFrame *frame = data;
442 int ret;
443
444 s->buf = buf;
445 s->size = buf_size;
446
447 if (buf_size < 16)
448 return AVERROR_INVALIDDATA;
449
450 if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
451 return ret;
452
453 if ((ret = vmd_decode(s, frame)) < 0)
454 return ret;
455
456 /* make the palette available on the way out */
457 memcpy(frame->data[1], s->palette, PALETTE_COUNT * 4);
458
459 /* shuffle frames */
460 av_frame_unref(s->prev_frame);
461 if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
462 return ret;
463
464 *got_frame = 1;
465
466 /* report that the buffer was completely consumed */
467 return buf_size;
468 }
469
470 AVCodec ff_vmdvideo_decoder = {
471 .name = "vmdvideo",
472 .long_name = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
473 .type = AVMEDIA_TYPE_VIDEO,
474 .id = AV_CODEC_ID_VMDVIDEO,
475 .priv_data_size = sizeof(VmdVideoContext),
476 .init = vmdvideo_decode_init,
477 .close = vmdvideo_decode_end,
478 .decode = vmdvideo_decode_frame,
479 .capabilities = AV_CODEC_CAP_DR1,
480 };
481