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source: vbox/trunk/src/libs/ffmpeg-20060710/libavcodec/cinepak.c@ 10184

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1/*
2 * Cinepak Video Decoder
3 * Copyright (C) 2003 the ffmpeg project
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 */
20
21/**
22 * @file cinepak.c
23 * Cinepak video decoder
24 * by Ewald Snel <[email protected]>
25 * For more information on the Cinepak algorithm, visit:
26 * http://www.csse.monash.edu.au/~timf/
27 */
28
29#include <stdio.h>
30#include <stdlib.h>
31#include <string.h>
32#include <unistd.h>
33
34#include "common.h"
35#include "avcodec.h"
36#include "dsputil.h"
37
38
39typedef struct {
40 uint8_t y0, y1, y2, y3;
41 uint8_t u, v;
42} cvid_codebook_t;
43
44#define MAX_STRIPS 32
45
46typedef struct {
47 uint16_t id;
48 uint16_t x1, y1;
49 uint16_t x2, y2;
50 cvid_codebook_t v4_codebook[256];
51 cvid_codebook_t v1_codebook[256];
52} cvid_strip_t;
53
54typedef struct CinepakContext {
55
56 AVCodecContext *avctx;
57 DSPContext dsp;
58 AVFrame frame;
59
60 unsigned char *data;
61 int size;
62
63 int width, height;
64
65 int palette_video;
66 cvid_strip_t strips[MAX_STRIPS];
67
68} CinepakContext;
69
70static void cinepak_decode_codebook (cvid_codebook_t *codebook,
71 int chunk_id, int size, uint8_t *data)
72{
73 uint8_t *eod = (data + size);
74 uint32_t flag, mask;
75 int i, n;
76
77 /* check if this chunk contains 4- or 6-element vectors */
78 n = (chunk_id & 0x0400) ? 4 : 6;
79 flag = 0;
80 mask = 0;
81
82 for (i=0; i < 256; i++) {
83 if ((chunk_id & 0x0100) && !(mask >>= 1)) {
84 if ((data + 4) > eod)
85 break;
86
87 flag = BE_32 (data);
88 data += 4;
89 mask = 0x80000000;
90 }
91
92 if (!(chunk_id & 0x0100) || (flag & mask)) {
93 if ((data + n) > eod)
94 break;
95
96 if (n == 6) {
97 codebook[i].y0 = *data++;
98 codebook[i].y1 = *data++;
99 codebook[i].y2 = *data++;
100 codebook[i].y3 = *data++;
101 codebook[i].u = 128 + *data++;
102 codebook[i].v = 128 + *data++;
103 } else {
104 /* this codebook type indicates either greyscale or
105 * palettized video; if palettized, U & V components will
106 * not be used so it is safe to set them to 128 for the
107 * benefit of greyscale rendering in YUV420P */
108 codebook[i].y0 = *data++;
109 codebook[i].y1 = *data++;
110 codebook[i].y2 = *data++;
111 codebook[i].y3 = *data++;
112 codebook[i].u = 128;
113 codebook[i].v = 128;
114 }
115 }
116 }
117}
118
119static int cinepak_decode_vectors (CinepakContext *s, cvid_strip_t *strip,
120 int chunk_id, int size, uint8_t *data)
121{
122 uint8_t *eod = (data + size);
123 uint32_t flag, mask;
124 cvid_codebook_t *codebook;
125 unsigned int x, y;
126 uint32_t iy[4];
127 uint32_t iu[2];
128 uint32_t iv[2];
129
130 flag = 0;
131 mask = 0;
132
133 for (y=strip->y1; y < strip->y2; y+=4) {
134
135 iy[0] = strip->x1 + (y * s->frame.linesize[0]);
136 iy[1] = iy[0] + s->frame.linesize[0];
137 iy[2] = iy[1] + s->frame.linesize[0];
138 iy[3] = iy[2] + s->frame.linesize[0];
139 iu[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[1]);
140 iu[1] = iu[0] + s->frame.linesize[1];
141 iv[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[2]);
142 iv[1] = iv[0] + s->frame.linesize[2];
143
144 for (x=strip->x1; x < strip->x2; x+=4) {
145 if ((chunk_id & 0x0100) && !(mask >>= 1)) {
146 if ((data + 4) > eod)
147 return -1;
148
149 flag = BE_32 (data);
150 data += 4;
151 mask = 0x80000000;
152 }
153
154 if (!(chunk_id & 0x0100) || (flag & mask)) {
155 if (!(chunk_id & 0x0200) && !(mask >>= 1)) {
156 if ((data + 4) > eod)
157 return -1;
158
159 flag = BE_32 (data);
160 data += 4;
161 mask = 0x80000000;
162 }
163
164 if ((chunk_id & 0x0200) || (~flag & mask)) {
165 if (data >= eod)
166 return -1;
167
168 codebook = &strip->v1_codebook[*data++];
169 s->frame.data[0][iy[0] + 0] = codebook->y0;
170 s->frame.data[0][iy[0] + 1] = codebook->y0;
171 s->frame.data[0][iy[1] + 0] = codebook->y0;
172 s->frame.data[0][iy[1] + 1] = codebook->y0;
173 if (!s->palette_video) {
174 s->frame.data[1][iu[0]] = codebook->u;
175 s->frame.data[2][iv[0]] = codebook->v;
176 }
177
178 s->frame.data[0][iy[0] + 2] = codebook->y1;
179 s->frame.data[0][iy[0] + 3] = codebook->y1;
180 s->frame.data[0][iy[1] + 2] = codebook->y1;
181 s->frame.data[0][iy[1] + 3] = codebook->y1;
182 if (!s->palette_video) {
183 s->frame.data[1][iu[0] + 1] = codebook->u;
184 s->frame.data[2][iv[0] + 1] = codebook->v;
185 }
186
187 s->frame.data[0][iy[2] + 0] = codebook->y2;
188 s->frame.data[0][iy[2] + 1] = codebook->y2;
189 s->frame.data[0][iy[3] + 0] = codebook->y2;
190 s->frame.data[0][iy[3] + 1] = codebook->y2;
191 if (!s->palette_video) {
192 s->frame.data[1][iu[1]] = codebook->u;
193 s->frame.data[2][iv[1]] = codebook->v;
194 }
195
196 s->frame.data[0][iy[2] + 2] = codebook->y3;
197 s->frame.data[0][iy[2] + 3] = codebook->y3;
198 s->frame.data[0][iy[3] + 2] = codebook->y3;
199 s->frame.data[0][iy[3] + 3] = codebook->y3;
200 if (!s->palette_video) {
201 s->frame.data[1][iu[1] + 1] = codebook->u;
202 s->frame.data[2][iv[1] + 1] = codebook->v;
203 }
204
205 } else if (flag & mask) {
206 if ((data + 4) > eod)
207 return -1;
208
209 codebook = &strip->v4_codebook[*data++];
210 s->frame.data[0][iy[0] + 0] = codebook->y0;
211 s->frame.data[0][iy[0] + 1] = codebook->y1;
212 s->frame.data[0][iy[1] + 0] = codebook->y2;
213 s->frame.data[0][iy[1] + 1] = codebook->y3;
214 if (!s->palette_video) {
215 s->frame.data[1][iu[0]] = codebook->u;
216 s->frame.data[2][iv[0]] = codebook->v;
217 }
218
219 codebook = &strip->v4_codebook[*data++];
220 s->frame.data[0][iy[0] + 2] = codebook->y0;
221 s->frame.data[0][iy[0] + 3] = codebook->y1;
222 s->frame.data[0][iy[1] + 2] = codebook->y2;
223 s->frame.data[0][iy[1] + 3] = codebook->y3;
224 if (!s->palette_video) {
225 s->frame.data[1][iu[0] + 1] = codebook->u;
226 s->frame.data[2][iv[0] + 1] = codebook->v;
227 }
228
229 codebook = &strip->v4_codebook[*data++];
230 s->frame.data[0][iy[2] + 0] = codebook->y0;
231 s->frame.data[0][iy[2] + 1] = codebook->y1;
232 s->frame.data[0][iy[3] + 0] = codebook->y2;
233 s->frame.data[0][iy[3] + 1] = codebook->y3;
234 if (!s->palette_video) {
235 s->frame.data[1][iu[1]] = codebook->u;
236 s->frame.data[2][iv[1]] = codebook->v;
237 }
238
239 codebook = &strip->v4_codebook[*data++];
240 s->frame.data[0][iy[2] + 2] = codebook->y0;
241 s->frame.data[0][iy[2] + 3] = codebook->y1;
242 s->frame.data[0][iy[3] + 2] = codebook->y2;
243 s->frame.data[0][iy[3] + 3] = codebook->y3;
244 if (!s->palette_video) {
245 s->frame.data[1][iu[1] + 1] = codebook->u;
246 s->frame.data[2][iv[1] + 1] = codebook->v;
247 }
248
249 }
250 }
251
252 iy[0] += 4; iy[1] += 4;
253 iy[2] += 4; iy[3] += 4;
254 iu[0] += 2; iu[1] += 2;
255 iv[0] += 2; iv[1] += 2;
256 }
257 }
258
259 return 0;
260}
261
262static int cinepak_decode_strip (CinepakContext *s,
263 cvid_strip_t *strip, uint8_t *data, int size)
264{
265 uint8_t *eod = (data + size);
266 int chunk_id, chunk_size;
267
268 /* coordinate sanity checks */
269 if (strip->x1 >= s->width || strip->x2 > s->width ||
270 strip->y1 >= s->height || strip->y2 > s->height ||
271 strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
272 return -1;
273
274 while ((data + 4) <= eod) {
275 chunk_id = BE_16 (&data[0]);
276 chunk_size = BE_16 (&data[2]) - 4;
277 if(chunk_size < 0)
278 return -1;
279
280 data += 4;
281 chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
282
283 switch (chunk_id) {
284
285 case 0x2000:
286 case 0x2100:
287 case 0x2400:
288 case 0x2500:
289 cinepak_decode_codebook (strip->v4_codebook, chunk_id,
290 chunk_size, data);
291 break;
292
293 case 0x2200:
294 case 0x2300:
295 case 0x2600:
296 case 0x2700:
297 cinepak_decode_codebook (strip->v1_codebook, chunk_id,
298 chunk_size, data);
299 break;
300
301 case 0x3000:
302 case 0x3100:
303 case 0x3200:
304 return cinepak_decode_vectors (s, strip, chunk_id,
305 chunk_size, data);
306 }
307
308 data += chunk_size;
309 }
310
311 return -1;
312}
313
314static int cinepak_decode (CinepakContext *s)
315{
316 uint8_t *eod = (s->data + s->size);
317 int i, result, strip_size, frame_flags, num_strips;
318 int y0 = 0;
319 int encoded_buf_size;
320 /* if true, Cinepak data is from a Sega FILM/CPK file */
321 int sega_film_data = 0;
322
323 if (s->size < 10)
324 return -1;
325
326 frame_flags = s->data[0];
327 num_strips = BE_16 (&s->data[8]);
328 encoded_buf_size = ((s->data[1] << 16) | BE_16 (&s->data[2]));
329 if (encoded_buf_size != s->size)
330 sega_film_data = 1;
331 if (sega_film_data)
332 s->data += 12;
333 else
334 s->data += 10;
335
336 if (num_strips > MAX_STRIPS)
337 num_strips = MAX_STRIPS;
338
339 for (i=0; i < num_strips; i++) {
340 if ((s->data + 12) > eod)
341 return -1;
342
343 s->strips[i].id = BE_16 (s->data);
344 s->strips[i].y1 = y0;
345 s->strips[i].x1 = 0;
346 s->strips[i].y2 = y0 + BE_16 (&s->data[8]);
347 s->strips[i].x2 = s->avctx->width;
348
349 strip_size = BE_16 (&s->data[2]) - 12;
350 s->data += 12;
351 strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
352
353 if ((i > 0) && !(frame_flags & 0x01)) {
354 memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
355 sizeof(s->strips[i].v4_codebook));
356 memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
357 sizeof(s->strips[i].v1_codebook));
358 }
359
360 result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
361
362 if (result != 0)
363 return result;
364
365 s->data += strip_size;
366 y0 = s->strips[i].y2;
367 }
368 return 0;
369}
370
371static int cinepak_decode_init(AVCodecContext *avctx)
372{
373 CinepakContext *s = (CinepakContext *)avctx->priv_data;
374
375 s->avctx = avctx;
376 s->width = (avctx->width + 3) & ~3;
377 s->height = (avctx->height + 3) & ~3;
378
379 // check for paletted data
380 if ((avctx->palctrl == NULL) || (avctx->bits_per_sample == 40)) {
381 s->palette_video = 0;
382 avctx->pix_fmt = PIX_FMT_YUV420P;
383 } else {
384 s->palette_video = 1;
385 avctx->pix_fmt = PIX_FMT_PAL8;
386 }
387
388 avctx->has_b_frames = 0;
389 dsputil_init(&s->dsp, avctx);
390
391 s->frame.data[0] = NULL;
392
393 return 0;
394}
395
396static int cinepak_decode_frame(AVCodecContext *avctx,
397 void *data, int *data_size,
398 uint8_t *buf, int buf_size)
399{
400 CinepakContext *s = (CinepakContext *)avctx->priv_data;
401
402 s->data = buf;
403 s->size = buf_size;
404
405 s->frame.reference = 1;
406 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
407 FF_BUFFER_HINTS_REUSABLE;
408 if (avctx->reget_buffer(avctx, &s->frame)) {
409 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
410 return -1;
411 }
412
413 cinepak_decode(s);
414
415 if (s->palette_video) {
416 memcpy (s->frame.data[1], avctx->palctrl->palette, AVPALETTE_SIZE);
417 if (avctx->palctrl->palette_changed) {
418 s->frame.palette_has_changed = 1;
419 avctx->palctrl->palette_changed = 0;
420 } else
421 s->frame.palette_has_changed = 0;
422 }
423
424 *data_size = sizeof(AVFrame);
425 *(AVFrame*)data = s->frame;
426
427 /* report that the buffer was completely consumed */
428 return buf_size;
429}
430
431static int cinepak_decode_end(AVCodecContext *avctx)
432{
433 CinepakContext *s = (CinepakContext *)avctx->priv_data;
434
435 if (s->frame.data[0])
436 avctx->release_buffer(avctx, &s->frame);
437
438 return 0;
439}
440
441AVCodec cinepak_decoder = {
442 "cinepak",
443 CODEC_TYPE_VIDEO,
444 CODEC_ID_CINEPAK,
445 sizeof(CinepakContext),
446 cinepak_decode_init,
447 NULL,
448 cinepak_decode_end,
449 cinepak_decode_frame,
450 CODEC_CAP_DR1,
451};
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