2 * Cinepak Video Decoder
3 * Copyright (C) 2003 the ffmpeg project
5 * This file is part of Libav.
7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * Cinepak video decoder
25 * @author Ewald Snel <ewald@rambo.its.tudelft.nl>
27 * @see For more information on the Cinepak algorithm, visit:
28 * http://www.csse.monash.edu.au/~timf/
29 * @see For more information on the quirky data inside Sega FILM/CPK files, visit:
30 * http://wiki.multimedia.cx/index.php?title=Sega_FILM
37 #include "libavutil/common.h"
38 #include "libavutil/intreadwrite.h"
43 uint8_t y0
, y1
, y2
, y3
;
53 cvid_codebook v4_codebook
[256];
54 cvid_codebook v1_codebook
[256];
57 typedef struct CinepakContext
{
59 AVCodecContext
*avctx
;
62 const unsigned char *data
;
68 cvid_strip strips
[MAX_STRIPS
];
70 int sega_film_skip_bytes
;
75 static void cinepak_decode_codebook (cvid_codebook
*codebook
,
76 int chunk_id
, int size
, const uint8_t *data
)
78 const uint8_t *eod
= (data
+ size
);
82 /* check if this chunk contains 4- or 6-element vectors */
83 n
= (chunk_id
& 0x04) ? 4 : 6;
87 for (i
=0; i
< 256; i
++) {
88 if ((chunk_id
& 0x01) && !(mask
>>= 1)) {
92 flag
= AV_RB32 (data
);
97 if (!(chunk_id
& 0x01) || (flag
& mask
)) {
102 codebook
[i
].y0
= *data
++;
103 codebook
[i
].y1
= *data
++;
104 codebook
[i
].y2
= *data
++;
105 codebook
[i
].y3
= *data
++;
106 codebook
[i
].u
= 128 + *data
++;
107 codebook
[i
].v
= 128 + *data
++;
109 /* this codebook type indicates either greyscale or
110 * palettized video; if palettized, U & V components will
111 * not be used so it is safe to set them to 128 for the
112 * benefit of greyscale rendering in YUV420P */
113 codebook
[i
].y0
= *data
++;
114 codebook
[i
].y1
= *data
++;
115 codebook
[i
].y2
= *data
++;
116 codebook
[i
].y3
= *data
++;
124 static int cinepak_decode_vectors (CinepakContext
*s
, cvid_strip
*strip
,
125 int chunk_id
, int size
, const uint8_t *data
)
127 const uint8_t *eod
= (data
+ size
);
129 cvid_codebook
*codebook
;
138 for (y
=strip
->y1
; y
< strip
->y2
; y
+=4) {
140 iy
[0] = strip
->x1
+ (y
* s
->frame
.linesize
[0]);
141 iy
[1] = iy
[0] + s
->frame
.linesize
[0];
142 iy
[2] = iy
[1] + s
->frame
.linesize
[0];
143 iy
[3] = iy
[2] + s
->frame
.linesize
[0];
144 iu
[0] = (strip
->x1
/2) + ((y
/2) * s
->frame
.linesize
[1]);
145 iu
[1] = iu
[0] + s
->frame
.linesize
[1];
146 iv
[0] = (strip
->x1
/2) + ((y
/2) * s
->frame
.linesize
[2]);
147 iv
[1] = iv
[0] + s
->frame
.linesize
[2];
149 for (x
=strip
->x1
; x
< strip
->x2
; x
+=4) {
150 if ((chunk_id
& 0x01) && !(mask
>>= 1)) {
151 if ((data
+ 4) > eod
)
152 return AVERROR_INVALIDDATA
;
154 flag
= AV_RB32 (data
);
159 if (!(chunk_id
& 0x01) || (flag
& mask
)) {
160 if (!(chunk_id
& 0x02) && !(mask
>>= 1)) {
161 if ((data
+ 4) > eod
)
162 return AVERROR_INVALIDDATA
;
164 flag
= AV_RB32 (data
);
169 if ((chunk_id
& 0x02) || (~flag
& mask
)) {
171 return AVERROR_INVALIDDATA
;
173 codebook
= &strip
->v1_codebook
[*data
++];
174 s
->frame
.data
[0][iy
[0] + 0] = codebook
->y0
;
175 s
->frame
.data
[0][iy
[0] + 1] = codebook
->y0
;
176 s
->frame
.data
[0][iy
[1] + 0] = codebook
->y0
;
177 s
->frame
.data
[0][iy
[1] + 1] = codebook
->y0
;
178 if (!s
->palette_video
) {
179 s
->frame
.data
[1][iu
[0]] = codebook
->u
;
180 s
->frame
.data
[2][iv
[0]] = codebook
->v
;
183 s
->frame
.data
[0][iy
[0] + 2] = codebook
->y1
;
184 s
->frame
.data
[0][iy
[0] + 3] = codebook
->y1
;
185 s
->frame
.data
[0][iy
[1] + 2] = codebook
->y1
;
186 s
->frame
.data
[0][iy
[1] + 3] = codebook
->y1
;
187 if (!s
->palette_video
) {
188 s
->frame
.data
[1][iu
[0] + 1] = codebook
->u
;
189 s
->frame
.data
[2][iv
[0] + 1] = codebook
->v
;
192 s
->frame
.data
[0][iy
[2] + 0] = codebook
->y2
;
193 s
->frame
.data
[0][iy
[2] + 1] = codebook
->y2
;
194 s
->frame
.data
[0][iy
[3] + 0] = codebook
->y2
;
195 s
->frame
.data
[0][iy
[3] + 1] = codebook
->y2
;
196 if (!s
->palette_video
) {
197 s
->frame
.data
[1][iu
[1]] = codebook
->u
;
198 s
->frame
.data
[2][iv
[1]] = codebook
->v
;
201 s
->frame
.data
[0][iy
[2] + 2] = codebook
->y3
;
202 s
->frame
.data
[0][iy
[2] + 3] = codebook
->y3
;
203 s
->frame
.data
[0][iy
[3] + 2] = codebook
->y3
;
204 s
->frame
.data
[0][iy
[3] + 3] = codebook
->y3
;
205 if (!s
->palette_video
) {
206 s
->frame
.data
[1][iu
[1] + 1] = codebook
->u
;
207 s
->frame
.data
[2][iv
[1] + 1] = codebook
->v
;
210 } else if (flag
& mask
) {
211 if ((data
+ 4) > eod
)
212 return AVERROR_INVALIDDATA
;
214 codebook
= &strip
->v4_codebook
[*data
++];
215 s
->frame
.data
[0][iy
[0] + 0] = codebook
->y0
;
216 s
->frame
.data
[0][iy
[0] + 1] = codebook
->y1
;
217 s
->frame
.data
[0][iy
[1] + 0] = codebook
->y2
;
218 s
->frame
.data
[0][iy
[1] + 1] = codebook
->y3
;
219 if (!s
->palette_video
) {
220 s
->frame
.data
[1][iu
[0]] = codebook
->u
;
221 s
->frame
.data
[2][iv
[0]] = codebook
->v
;
224 codebook
= &strip
->v4_codebook
[*data
++];
225 s
->frame
.data
[0][iy
[0] + 2] = codebook
->y0
;
226 s
->frame
.data
[0][iy
[0] + 3] = codebook
->y1
;
227 s
->frame
.data
[0][iy
[1] + 2] = codebook
->y2
;
228 s
->frame
.data
[0][iy
[1] + 3] = codebook
->y3
;
229 if (!s
->palette_video
) {
230 s
->frame
.data
[1][iu
[0] + 1] = codebook
->u
;
231 s
->frame
.data
[2][iv
[0] + 1] = codebook
->v
;
234 codebook
= &strip
->v4_codebook
[*data
++];
235 s
->frame
.data
[0][iy
[2] + 0] = codebook
->y0
;
236 s
->frame
.data
[0][iy
[2] + 1] = codebook
->y1
;
237 s
->frame
.data
[0][iy
[3] + 0] = codebook
->y2
;
238 s
->frame
.data
[0][iy
[3] + 1] = codebook
->y3
;
239 if (!s
->palette_video
) {
240 s
->frame
.data
[1][iu
[1]] = codebook
->u
;
241 s
->frame
.data
[2][iv
[1]] = codebook
->v
;
244 codebook
= &strip
->v4_codebook
[*data
++];
245 s
->frame
.data
[0][iy
[2] + 2] = codebook
->y0
;
246 s
->frame
.data
[0][iy
[2] + 3] = codebook
->y1
;
247 s
->frame
.data
[0][iy
[3] + 2] = codebook
->y2
;
248 s
->frame
.data
[0][iy
[3] + 3] = codebook
->y3
;
249 if (!s
->palette_video
) {
250 s
->frame
.data
[1][iu
[1] + 1] = codebook
->u
;
251 s
->frame
.data
[2][iv
[1] + 1] = codebook
->v
;
257 iy
[0] += 4; iy
[1] += 4;
258 iy
[2] += 4; iy
[3] += 4;
259 iu
[0] += 2; iu
[1] += 2;
260 iv
[0] += 2; iv
[1] += 2;
267 static int cinepak_decode_strip (CinepakContext
*s
,
268 cvid_strip
*strip
, const uint8_t *data
, int size
)
270 const uint8_t *eod
= (data
+ size
);
271 int chunk_id
, chunk_size
;
273 /* coordinate sanity checks */
274 if (strip
->x2
> s
->width
||
275 strip
->y2
> s
->height
||
276 strip
->x1
>= strip
->x2
|| strip
->y1
>= strip
->y2
)
277 return AVERROR_INVALIDDATA
;
279 while ((data
+ 4) <= eod
) {
281 chunk_size
= AV_RB24 (&data
[1]) - 4;
283 return AVERROR_INVALIDDATA
;
286 chunk_size
= ((data
+ chunk_size
) > eod
) ? (eod
- data
) : chunk_size
;
294 cinepak_decode_codebook (strip
->v4_codebook
, chunk_id
,
302 cinepak_decode_codebook (strip
->v1_codebook
, chunk_id
,
309 return cinepak_decode_vectors (s
, strip
, chunk_id
,
316 return AVERROR_INVALIDDATA
;
319 static int cinepak_decode (CinepakContext
*s
)
321 const uint8_t *eod
= (s
->data
+ s
->size
);
322 int i
, result
, strip_size
, frame_flags
, num_strips
;
324 int encoded_buf_size
;
327 return AVERROR_INVALIDDATA
;
329 frame_flags
= s
->data
[0];
330 num_strips
= AV_RB16 (&s
->data
[8]);
331 encoded_buf_size
= AV_RB24(&s
->data
[1]);
333 /* if this is the first frame, check for deviant Sega FILM data */
334 if (s
->sega_film_skip_bytes
== -1) {
335 if (!encoded_buf_size
) {
336 av_log_ask_for_sample(s
->avctx
, "encoded_buf_size is 0");
337 return AVERROR_PATCHWELCOME
;
339 if (encoded_buf_size
!= s
->size
&& (s
->size
% encoded_buf_size
) != 0) {
340 /* If the encoded frame size differs from the frame size as indicated
341 * by the container file, this data likely comes from a Sega FILM/CPK file.
342 * If the frame header is followed by the bytes FE 00 00 06 00 00 then
343 * this is probably one of the two known files that have 6 extra bytes
344 * after the frame header. Else, assume 2 extra bytes. The container
345 * size also cannot be a multiple of the encoded size. */
347 (s
->data
[10] == 0xFE) &&
348 (s
->data
[11] == 0x00) &&
349 (s
->data
[12] == 0x00) &&
350 (s
->data
[13] == 0x06) &&
351 (s
->data
[14] == 0x00) &&
352 (s
->data
[15] == 0x00))
353 s
->sega_film_skip_bytes
= 6;
355 s
->sega_film_skip_bytes
= 2;
357 s
->sega_film_skip_bytes
= 0;
360 s
->data
+= 10 + s
->sega_film_skip_bytes
;
362 num_strips
= FFMIN(num_strips
, MAX_STRIPS
);
364 for (i
=0; i
< num_strips
; i
++) {
365 if ((s
->data
+ 12) > eod
)
366 return AVERROR_INVALIDDATA
;
368 s
->strips
[i
].id
= s
->data
[0];
369 s
->strips
[i
].y1
= y0
;
371 s
->strips
[i
].y2
= y0
+ AV_RB16 (&s
->data
[8]);
372 s
->strips
[i
].x2
= s
->avctx
->width
;
374 strip_size
= AV_RB24 (&s
->data
[1]) - 12;
376 return AVERROR_INVALIDDATA
;
378 strip_size
= ((s
->data
+ strip_size
) > eod
) ? (eod
- s
->data
) : strip_size
;
380 if ((i
> 0) && !(frame_flags
& 0x01)) {
381 memcpy (s
->strips
[i
].v4_codebook
, s
->strips
[i
-1].v4_codebook
,
382 sizeof(s
->strips
[i
].v4_codebook
));
383 memcpy (s
->strips
[i
].v1_codebook
, s
->strips
[i
-1].v1_codebook
,
384 sizeof(s
->strips
[i
].v1_codebook
));
387 result
= cinepak_decode_strip (s
, &s
->strips
[i
], s
->data
, strip_size
);
392 s
->data
+= strip_size
;
393 y0
= s
->strips
[i
].y2
;
398 static av_cold
int cinepak_decode_init(AVCodecContext
*avctx
)
400 CinepakContext
*s
= avctx
->priv_data
;
403 s
->width
= (avctx
->width
+ 3) & ~3;
404 s
->height
= (avctx
->height
+ 3) & ~3;
405 s
->sega_film_skip_bytes
= -1; /* uninitialized state */
407 // check for paletted data
408 if (avctx
->bits_per_coded_sample
!= 8) {
409 s
->palette_video
= 0;
410 avctx
->pix_fmt
= AV_PIX_FMT_YUV420P
;
412 s
->palette_video
= 1;
413 avctx
->pix_fmt
= AV_PIX_FMT_PAL8
;
416 s
->frame
.data
[0] = NULL
;
421 static int cinepak_decode_frame(AVCodecContext
*avctx
,
422 void *data
, int *got_frame
,
425 const uint8_t *buf
= avpkt
->data
;
426 int ret
= 0, buf_size
= avpkt
->size
;
427 CinepakContext
*s
= avctx
->priv_data
;
432 s
->frame
.reference
= 1;
433 s
->frame
.buffer_hints
= FF_BUFFER_HINTS_VALID
| FF_BUFFER_HINTS_PRESERVE
|
434 FF_BUFFER_HINTS_REUSABLE
;
435 if ((ret
= avctx
->reget_buffer(avctx
, &s
->frame
))) {
436 av_log(avctx
, AV_LOG_ERROR
, "reget_buffer() failed\n");
440 if (s
->palette_video
) {
441 const uint8_t *pal
= av_packet_get_side_data(avpkt
, AV_PKT_DATA_PALETTE
, NULL
);
443 s
->frame
.palette_has_changed
= 1;
444 memcpy(s
->pal
, pal
, AVPALETTE_SIZE
);
450 if (s
->palette_video
)
451 memcpy (s
->frame
.data
[1], s
->pal
, AVPALETTE_SIZE
);
454 *(AVFrame
*)data
= s
->frame
;
456 /* report that the buffer was completely consumed */
460 static av_cold
int cinepak_decode_end(AVCodecContext
*avctx
)
462 CinepakContext
*s
= avctx
->priv_data
;
464 if (s
->frame
.data
[0])
465 avctx
->release_buffer(avctx
, &s
->frame
);
470 AVCodec ff_cinepak_decoder
= {
472 .type
= AVMEDIA_TYPE_VIDEO
,
473 .id
= AV_CODEC_ID_CINEPAK
,
474 .priv_data_size
= sizeof(CinepakContext
),
475 .init
= cinepak_decode_init
,
476 .close
= cinepak_decode_end
,
477 .decode
= cinepak_decode_frame
,
478 .capabilities
= CODEC_CAP_DR1
,
479 .long_name
= NULL_IF_CONFIG_SMALL("Cinepak"),