2 * Cinepak Video Decoder
3 * Copyright (C) 2003 the ffmpeg project
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.
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.
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
23 * Cinepak video decoder
24 * by Ewald Snel <ewald@rambo.its.tudelft.nl>
25 * For more information on the Cinepak algorithm, visit:
26 * http://www.csse.monash.edu.au/~timf/
40 uint8_t y0
, y1
, y2
, y3
;
50 cvid_codebook_t v4_codebook
[256];
51 cvid_codebook_t v1_codebook
[256];
54 typedef struct CinepakContext
{
56 AVCodecContext
*avctx
;
66 cvid_strip_t strips
[MAX_STRIPS
];
70 static void cinepak_decode_codebook (cvid_codebook_t
*codebook
,
71 int chunk_id
, int size
, uint8_t *data
)
73 uint8_t *eod
= (data
+ size
);
77 /* check if this chunk contains 4- or 6-element vectors */
78 n
= (chunk_id
& 0x0400) ? 4 : 6;
82 for (i
=0; i
< 256; i
++) {
83 if ((chunk_id
& 0x0100) && !(mask
>>= 1)) {
92 if (!(chunk_id
& 0x0100) || (flag
& mask
)) {
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
++;
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
++;
119 static int cinepak_decode_vectors (CinepakContext
*s
, cvid_strip_t
*strip
,
120 int chunk_id
, int size
, uint8_t *data
)
122 uint8_t *eod
= (data
+ size
);
124 cvid_codebook_t
*codebook
;
133 for (y
=strip
->y1
; y
< strip
->y2
; y
+=4) {
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];
144 for (x
=strip
->x1
; x
< strip
->x2
; x
+=4) {
145 if ((chunk_id
& 0x0100) && !(mask
>>= 1)) {
146 if ((data
+ 4) > eod
)
154 if (!(chunk_id
& 0x0100) || (flag
& mask
)) {
155 if (!(chunk_id
& 0x0200) && !(mask
>>= 1)) {
156 if ((data
+ 4) > eod
)
164 if ((chunk_id
& 0x0200) || (~flag
& mask
)) {
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
;
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
;
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
;
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
;
205 } else if (flag
& mask
) {
206 if ((data
+ 4) > eod
)
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
;
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
;
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
;
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
;
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;
262 static int cinepak_decode_strip (CinepakContext
*s
,
263 cvid_strip_t
*strip
, uint8_t *data
, int size
)
265 uint8_t *eod
= (data
+ size
);
266 int chunk_id
, chunk_size
;
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
)
274 while ((data
+ 4) <= eod
) {
275 chunk_id
= BE_16 (&data
[0]);
276 chunk_size
= BE_16 (&data
[2]) - 4;
281 chunk_size
= ((data
+ chunk_size
) > eod
) ? (eod
- data
) : chunk_size
;
289 cinepak_decode_codebook (strip
->v4_codebook
, chunk_id
,
297 cinepak_decode_codebook (strip
->v1_codebook
, chunk_id
,
304 return cinepak_decode_vectors (s
, strip
, chunk_id
,
314 static int cinepak_decode (CinepakContext
*s
)
316 uint8_t *eod
= (s
->data
+ s
->size
);
317 int i
, result
, strip_size
, frame_flags
, num_strips
;
319 int encoded_buf_size
;
320 /* if true, Cinepak data is from a Sega FILM/CPK file */
321 int sega_film_data
= 0;
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
)
336 if (num_strips
> MAX_STRIPS
)
337 num_strips
= MAX_STRIPS
;
339 for (i
=0; i
< num_strips
; i
++) {
340 if ((s
->data
+ 12) > eod
)
343 s
->strips
[i
].id
= BE_16 (s
->data
);
344 s
->strips
[i
].y1
= y0
;
346 s
->strips
[i
].y2
= y0
+ BE_16 (&s
->data
[8]);
347 s
->strips
[i
].x2
= s
->avctx
->width
;
349 strip_size
= BE_16 (&s
->data
[2]) - 12;
351 strip_size
= ((s
->data
+ strip_size
) > eod
) ? (eod
- s
->data
) : strip_size
;
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
));
360 result
= cinepak_decode_strip (s
, &s
->strips
[i
], s
->data
, strip_size
);
365 s
->data
+= strip_size
;
366 y0
= s
->strips
[i
].y2
;
371 static int cinepak_decode_init(AVCodecContext
*avctx
)
373 CinepakContext
*s
= (CinepakContext
*)avctx
->priv_data
;
376 s
->width
= (avctx
->width
+ 3) & ~3;
377 s
->height
= (avctx
->height
+ 3) & ~3;
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
;
384 s
->palette_video
= 1;
385 avctx
->pix_fmt
= PIX_FMT_PAL8
;
388 avctx
->has_b_frames
= 0;
389 dsputil_init(&s
->dsp
, avctx
);
391 s
->frame
.data
[0] = NULL
;
396 static int cinepak_decode_frame(AVCodecContext
*avctx
,
397 void *data
, int *data_size
,
398 uint8_t *buf
, int buf_size
)
400 CinepakContext
*s
= (CinepakContext
*)avctx
->priv_data
;
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");
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;
421 s
->frame
.palette_has_changed
= 0;
424 *data_size
= sizeof(AVFrame
);
425 *(AVFrame
*)data
= s
->frame
;
427 /* report that the buffer was completely consumed */
431 static int cinepak_decode_end(AVCodecContext
*avctx
)
433 CinepakContext
*s
= (CinepakContext
*)avctx
->priv_data
;
435 if (s
->frame
.data
[0])
436 avctx
->release_buffer(avctx
, &s
->frame
);
441 AVCodec cinepak_decoder
= {
445 sizeof(CinepakContext
),
449 cinepak_decode_frame
,