2 * Cinepak Video Decoder
3 * Copyright (C) 2003 the ffmpeg project
5 * This file is part of FFmpeg.
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.
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.
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
23 * @file libavcodec/cinepak.c
24 * Cinepak video decoder
25 * by Ewald Snel <ewald@rambo.its.tudelft.nl>
26 * For more information on the Cinepak algorithm, visit:
27 * http://www.csse.monash.edu.au/~timf/
28 * For more information on the quirky data inside Sega FILM/CPK files, visit:
29 * http://wiki.multimedia.cx/index.php?title=Sega_FILM
37 #include "libavutil/intreadwrite.h"
42 uint8_t y0
, y1
, y2
, y3
;
52 cvid_codebook v4_codebook
[256];
53 cvid_codebook v1_codebook
[256];
56 typedef struct CinepakContext
{
58 AVCodecContext
*avctx
;
61 const unsigned char *data
;
67 cvid_strip strips
[MAX_STRIPS
];
69 int sega_film_skip_bytes
;
73 static void cinepak_decode_codebook (cvid_codebook
*codebook
,
74 int chunk_id
, int size
, const uint8_t *data
)
76 const uint8_t *eod
= (data
+ size
);
80 /* check if this chunk contains 4- or 6-element vectors */
81 n
= (chunk_id
& 0x04) ? 4 : 6;
85 for (i
=0; i
< 256; i
++) {
86 if ((chunk_id
& 0x01) && !(mask
>>= 1)) {
90 flag
= AV_RB32 (data
);
95 if (!(chunk_id
& 0x01) || (flag
& mask
)) {
100 codebook
[i
].y0
= *data
++;
101 codebook
[i
].y1
= *data
++;
102 codebook
[i
].y2
= *data
++;
103 codebook
[i
].y3
= *data
++;
104 codebook
[i
].u
= 128 + *data
++;
105 codebook
[i
].v
= 128 + *data
++;
107 /* this codebook type indicates either greyscale or
108 * palettized video; if palettized, U & V components will
109 * not be used so it is safe to set them to 128 for the
110 * benefit of greyscale rendering in YUV420P */
111 codebook
[i
].y0
= *data
++;
112 codebook
[i
].y1
= *data
++;
113 codebook
[i
].y2
= *data
++;
114 codebook
[i
].y3
= *data
++;
122 static int cinepak_decode_vectors (CinepakContext
*s
, cvid_strip
*strip
,
123 int chunk_id
, int size
, const uint8_t *data
)
125 const uint8_t *eod
= (data
+ size
);
127 cvid_codebook
*codebook
;
136 for (y
=strip
->y1
; y
< strip
->y2
; y
+=4) {
138 iy
[0] = strip
->x1
+ (y
* s
->frame
.linesize
[0]);
139 iy
[1] = iy
[0] + s
->frame
.linesize
[0];
140 iy
[2] = iy
[1] + s
->frame
.linesize
[0];
141 iy
[3] = iy
[2] + s
->frame
.linesize
[0];
142 iu
[0] = (strip
->x1
/2) + ((y
/2) * s
->frame
.linesize
[1]);
143 iu
[1] = iu
[0] + s
->frame
.linesize
[1];
144 iv
[0] = (strip
->x1
/2) + ((y
/2) * s
->frame
.linesize
[2]);
145 iv
[1] = iv
[0] + s
->frame
.linesize
[2];
147 for (x
=strip
->x1
; x
< strip
->x2
; x
+=4) {
148 if ((chunk_id
& 0x01) && !(mask
>>= 1)) {
149 if ((data
+ 4) > eod
)
152 flag
= AV_RB32 (data
);
157 if (!(chunk_id
& 0x01) || (flag
& mask
)) {
158 if (!(chunk_id
& 0x02) && !(mask
>>= 1)) {
159 if ((data
+ 4) > eod
)
162 flag
= AV_RB32 (data
);
167 if ((chunk_id
& 0x02) || (~flag
& mask
)) {
171 codebook
= &strip
->v1_codebook
[*data
++];
172 s
->frame
.data
[0][iy
[0] + 0] = codebook
->y0
;
173 s
->frame
.data
[0][iy
[0] + 1] = codebook
->y0
;
174 s
->frame
.data
[0][iy
[1] + 0] = codebook
->y0
;
175 s
->frame
.data
[0][iy
[1] + 1] = codebook
->y0
;
176 if (!s
->palette_video
) {
177 s
->frame
.data
[1][iu
[0]] = codebook
->u
;
178 s
->frame
.data
[2][iv
[0]] = codebook
->v
;
181 s
->frame
.data
[0][iy
[0] + 2] = codebook
->y1
;
182 s
->frame
.data
[0][iy
[0] + 3] = codebook
->y1
;
183 s
->frame
.data
[0][iy
[1] + 2] = codebook
->y1
;
184 s
->frame
.data
[0][iy
[1] + 3] = codebook
->y1
;
185 if (!s
->palette_video
) {
186 s
->frame
.data
[1][iu
[0] + 1] = codebook
->u
;
187 s
->frame
.data
[2][iv
[0] + 1] = codebook
->v
;
190 s
->frame
.data
[0][iy
[2] + 0] = codebook
->y2
;
191 s
->frame
.data
[0][iy
[2] + 1] = codebook
->y2
;
192 s
->frame
.data
[0][iy
[3] + 0] = codebook
->y2
;
193 s
->frame
.data
[0][iy
[3] + 1] = codebook
->y2
;
194 if (!s
->palette_video
) {
195 s
->frame
.data
[1][iu
[1]] = codebook
->u
;
196 s
->frame
.data
[2][iv
[1]] = codebook
->v
;
199 s
->frame
.data
[0][iy
[2] + 2] = codebook
->y3
;
200 s
->frame
.data
[0][iy
[2] + 3] = codebook
->y3
;
201 s
->frame
.data
[0][iy
[3] + 2] = codebook
->y3
;
202 s
->frame
.data
[0][iy
[3] + 3] = codebook
->y3
;
203 if (!s
->palette_video
) {
204 s
->frame
.data
[1][iu
[1] + 1] = codebook
->u
;
205 s
->frame
.data
[2][iv
[1] + 1] = codebook
->v
;
208 } else if (flag
& mask
) {
209 if ((data
+ 4) > eod
)
212 codebook
= &strip
->v4_codebook
[*data
++];
213 s
->frame
.data
[0][iy
[0] + 0] = codebook
->y0
;
214 s
->frame
.data
[0][iy
[0] + 1] = codebook
->y1
;
215 s
->frame
.data
[0][iy
[1] + 0] = codebook
->y2
;
216 s
->frame
.data
[0][iy
[1] + 1] = codebook
->y3
;
217 if (!s
->palette_video
) {
218 s
->frame
.data
[1][iu
[0]] = codebook
->u
;
219 s
->frame
.data
[2][iv
[0]] = codebook
->v
;
222 codebook
= &strip
->v4_codebook
[*data
++];
223 s
->frame
.data
[0][iy
[0] + 2] = codebook
->y0
;
224 s
->frame
.data
[0][iy
[0] + 3] = codebook
->y1
;
225 s
->frame
.data
[0][iy
[1] + 2] = codebook
->y2
;
226 s
->frame
.data
[0][iy
[1] + 3] = codebook
->y3
;
227 if (!s
->palette_video
) {
228 s
->frame
.data
[1][iu
[0] + 1] = codebook
->u
;
229 s
->frame
.data
[2][iv
[0] + 1] = codebook
->v
;
232 codebook
= &strip
->v4_codebook
[*data
++];
233 s
->frame
.data
[0][iy
[2] + 0] = codebook
->y0
;
234 s
->frame
.data
[0][iy
[2] + 1] = codebook
->y1
;
235 s
->frame
.data
[0][iy
[3] + 0] = codebook
->y2
;
236 s
->frame
.data
[0][iy
[3] + 1] = codebook
->y3
;
237 if (!s
->palette_video
) {
238 s
->frame
.data
[1][iu
[1]] = codebook
->u
;
239 s
->frame
.data
[2][iv
[1]] = codebook
->v
;
242 codebook
= &strip
->v4_codebook
[*data
++];
243 s
->frame
.data
[0][iy
[2] + 2] = codebook
->y0
;
244 s
->frame
.data
[0][iy
[2] + 3] = codebook
->y1
;
245 s
->frame
.data
[0][iy
[3] + 2] = codebook
->y2
;
246 s
->frame
.data
[0][iy
[3] + 3] = codebook
->y3
;
247 if (!s
->palette_video
) {
248 s
->frame
.data
[1][iu
[1] + 1] = codebook
->u
;
249 s
->frame
.data
[2][iv
[1] + 1] = codebook
->v
;
255 iy
[0] += 4; iy
[1] += 4;
256 iy
[2] += 4; iy
[3] += 4;
257 iu
[0] += 2; iu
[1] += 2;
258 iv
[0] += 2; iv
[1] += 2;
265 static int cinepak_decode_strip (CinepakContext
*s
,
266 cvid_strip
*strip
, const uint8_t *data
, int size
)
268 const uint8_t *eod
= (data
+ size
);
269 int chunk_id
, chunk_size
;
271 /* coordinate sanity checks */
272 if (strip
->x1
>= s
->width
|| strip
->x2
> s
->width
||
273 strip
->y1
>= s
->height
|| strip
->y2
> s
->height
||
274 strip
->x1
>= strip
->x2
|| strip
->y1
>= strip
->y2
)
277 while ((data
+ 4) <= eod
) {
279 chunk_size
= AV_RB24 (&data
[1]) - 4;
284 chunk_size
= ((data
+ chunk_size
) > eod
) ? (eod
- data
) : chunk_size
;
292 cinepak_decode_codebook (strip
->v4_codebook
, chunk_id
,
300 cinepak_decode_codebook (strip
->v1_codebook
, chunk_id
,
307 return cinepak_decode_vectors (s
, strip
, chunk_id
,
317 static int cinepak_decode (CinepakContext
*s
)
319 const uint8_t *eod
= (s
->data
+ s
->size
);
320 int i
, result
, strip_size
, frame_flags
, num_strips
;
322 int encoded_buf_size
;
327 frame_flags
= s
->data
[0];
328 num_strips
= AV_RB16 (&s
->data
[8]);
329 encoded_buf_size
= ((s
->data
[1] << 16) | AV_RB16 (&s
->data
[2]));
331 /* if this is the first frame, check for deviant Sega FILM data */
332 if (s
->sega_film_skip_bytes
== -1) {
333 if (encoded_buf_size
!= s
->size
) {
334 /* If the encoded frame size differs from the frame size as indicated
335 * by the container file, this data likely comes from a Sega FILM/CPK file.
336 * If the frame header is followed by the bytes FE 00 00 06 00 00 then
337 * this is probably one of the two known files that have 6 extra bytes
338 * after the frame header. Else, assume 2 extra bytes. */
339 if ((s
->data
[10] == 0xFE) &&
340 (s
->data
[11] == 0x00) &&
341 (s
->data
[12] == 0x00) &&
342 (s
->data
[13] == 0x06) &&
343 (s
->data
[14] == 0x00) &&
344 (s
->data
[15] == 0x00))
345 s
->sega_film_skip_bytes
= 6;
347 s
->sega_film_skip_bytes
= 2;
349 s
->sega_film_skip_bytes
= 0;
352 s
->data
+= 10 + s
->sega_film_skip_bytes
;
354 if (num_strips
> MAX_STRIPS
)
355 num_strips
= MAX_STRIPS
;
357 for (i
=0; i
< num_strips
; i
++) {
358 if ((s
->data
+ 12) > eod
)
361 s
->strips
[i
].id
= s
->data
[0];
362 s
->strips
[i
].y1
= y0
;
364 s
->strips
[i
].y2
= y0
+ AV_RB16 (&s
->data
[8]);
365 s
->strips
[i
].x2
= s
->avctx
->width
;
367 strip_size
= AV_RB24 (&s
->data
[1]) - 12;
369 strip_size
= ((s
->data
+ strip_size
) > eod
) ? (eod
- s
->data
) : strip_size
;
371 if ((i
> 0) && !(frame_flags
& 0x01)) {
372 memcpy (s
->strips
[i
].v4_codebook
, s
->strips
[i
-1].v4_codebook
,
373 sizeof(s
->strips
[i
].v4_codebook
));
374 memcpy (s
->strips
[i
].v1_codebook
, s
->strips
[i
-1].v1_codebook
,
375 sizeof(s
->strips
[i
].v1_codebook
));
378 result
= cinepak_decode_strip (s
, &s
->strips
[i
], s
->data
, strip_size
);
383 s
->data
+= strip_size
;
384 y0
= s
->strips
[i
].y2
;
389 static av_cold
int cinepak_decode_init(AVCodecContext
*avctx
)
391 CinepakContext
*s
= avctx
->priv_data
;
394 s
->width
= (avctx
->width
+ 3) & ~3;
395 s
->height
= (avctx
->height
+ 3) & ~3;
396 s
->sega_film_skip_bytes
= -1; /* uninitialized state */
398 // check for paletted data
399 if ((avctx
->palctrl
== NULL
) || (avctx
->bits_per_coded_sample
== 40)) {
400 s
->palette_video
= 0;
401 avctx
->pix_fmt
= PIX_FMT_YUV420P
;
403 s
->palette_video
= 1;
404 avctx
->pix_fmt
= PIX_FMT_PAL8
;
407 s
->frame
.data
[0] = NULL
;
412 static int cinepak_decode_frame(AVCodecContext
*avctx
,
413 void *data
, int *data_size
,
414 const uint8_t *buf
, int buf_size
)
416 CinepakContext
*s
= avctx
->priv_data
;
421 s
->frame
.reference
= 1;
422 s
->frame
.buffer_hints
= FF_BUFFER_HINTS_VALID
| FF_BUFFER_HINTS_PRESERVE
|
423 FF_BUFFER_HINTS_REUSABLE
;
424 if (avctx
->reget_buffer(avctx
, &s
->frame
)) {
425 av_log(avctx
, AV_LOG_ERROR
, "reget_buffer() failed\n");
431 if (s
->palette_video
) {
432 memcpy (s
->frame
.data
[1], avctx
->palctrl
->palette
, AVPALETTE_SIZE
);
433 if (avctx
->palctrl
->palette_changed
) {
434 s
->frame
.palette_has_changed
= 1;
435 avctx
->palctrl
->palette_changed
= 0;
437 s
->frame
.palette_has_changed
= 0;
440 *data_size
= sizeof(AVFrame
);
441 *(AVFrame
*)data
= s
->frame
;
443 /* report that the buffer was completely consumed */
447 static av_cold
int cinepak_decode_end(AVCodecContext
*avctx
)
449 CinepakContext
*s
= avctx
->priv_data
;
451 if (s
->frame
.data
[0])
452 avctx
->release_buffer(avctx
, &s
->frame
);
457 AVCodec cinepak_decoder
= {
461 sizeof(CinepakContext
),
465 cinepak_decode_frame
,
467 .long_name
= NULL_IF_CONFIG_SMALL("Cinepak"),