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"
44 uint8_t y0
, y1
, y2
, y3
;
54 cvid_codebook v4_codebook
[256];
55 cvid_codebook v1_codebook
[256];
58 typedef struct CinepakContext
{
60 AVCodecContext
*avctx
;
63 const unsigned char *data
;
69 cvid_strip strips
[MAX_STRIPS
];
71 int sega_film_skip_bytes
;
76 static void cinepak_decode_codebook (cvid_codebook
*codebook
,
77 int chunk_id
, int size
, const uint8_t *data
)
79 const uint8_t *eod
= (data
+ size
);
83 /* check if this chunk contains 4- or 6-element vectors */
84 n
= (chunk_id
& 0x04) ? 4 : 6;
88 for (i
=0; i
< 256; i
++) {
89 if ((chunk_id
& 0x01) && !(mask
>>= 1)) {
93 flag
= AV_RB32 (data
);
98 if (!(chunk_id
& 0x01) || (flag
& mask
)) {
103 codebook
[i
].y0
= *data
++;
104 codebook
[i
].y1
= *data
++;
105 codebook
[i
].y2
= *data
++;
106 codebook
[i
].y3
= *data
++;
107 codebook
[i
].u
= 128 + *data
++;
108 codebook
[i
].v
= 128 + *data
++;
110 /* this codebook type indicates either greyscale or
111 * palettized video; if palettized, U & V components will
112 * not be used so it is safe to set them to 128 for the
113 * benefit of greyscale rendering in YUV420P */
114 codebook
[i
].y0
= *data
++;
115 codebook
[i
].y1
= *data
++;
116 codebook
[i
].y2
= *data
++;
117 codebook
[i
].y3
= *data
++;
125 static int cinepak_decode_vectors (CinepakContext
*s
, cvid_strip
*strip
,
126 int chunk_id
, int size
, const uint8_t *data
)
128 const uint8_t *eod
= (data
+ size
);
130 cvid_codebook
*codebook
;
139 for (y
=strip
->y1
; y
< strip
->y2
; y
+=4) {
141 iy
[0] = strip
->x1
+ (y
* s
->frame
.linesize
[0]);
142 iy
[1] = iy
[0] + s
->frame
.linesize
[0];
143 iy
[2] = iy
[1] + s
->frame
.linesize
[0];
144 iy
[3] = iy
[2] + s
->frame
.linesize
[0];
145 iu
[0] = (strip
->x1
/2) + ((y
/2) * s
->frame
.linesize
[1]);
146 iu
[1] = iu
[0] + s
->frame
.linesize
[1];
147 iv
[0] = (strip
->x1
/2) + ((y
/2) * s
->frame
.linesize
[2]);
148 iv
[1] = iv
[0] + s
->frame
.linesize
[2];
150 for (x
=strip
->x1
; x
< strip
->x2
; x
+=4) {
151 if ((chunk_id
& 0x01) && !(mask
>>= 1)) {
152 if ((data
+ 4) > eod
)
153 return AVERROR_INVALIDDATA
;
155 flag
= AV_RB32 (data
);
160 if (!(chunk_id
& 0x01) || (flag
& mask
)) {
161 if (!(chunk_id
& 0x02) && !(mask
>>= 1)) {
162 if ((data
+ 4) > eod
)
163 return AVERROR_INVALIDDATA
;
165 flag
= AV_RB32 (data
);
170 if ((chunk_id
& 0x02) || (~flag
& mask
)) {
172 return AVERROR_INVALIDDATA
;
174 codebook
= &strip
->v1_codebook
[*data
++];
175 s
->frame
.data
[0][iy
[0] + 0] = codebook
->y0
;
176 s
->frame
.data
[0][iy
[0] + 1] = codebook
->y0
;
177 s
->frame
.data
[0][iy
[1] + 0] = codebook
->y0
;
178 s
->frame
.data
[0][iy
[1] + 1] = codebook
->y0
;
179 if (!s
->palette_video
) {
180 s
->frame
.data
[1][iu
[0]] = codebook
->u
;
181 s
->frame
.data
[2][iv
[0]] = codebook
->v
;
184 s
->frame
.data
[0][iy
[0] + 2] = codebook
->y1
;
185 s
->frame
.data
[0][iy
[0] + 3] = codebook
->y1
;
186 s
->frame
.data
[0][iy
[1] + 2] = codebook
->y1
;
187 s
->frame
.data
[0][iy
[1] + 3] = codebook
->y1
;
188 if (!s
->palette_video
) {
189 s
->frame
.data
[1][iu
[0] + 1] = codebook
->u
;
190 s
->frame
.data
[2][iv
[0] + 1] = codebook
->v
;
193 s
->frame
.data
[0][iy
[2] + 0] = codebook
->y2
;
194 s
->frame
.data
[0][iy
[2] + 1] = codebook
->y2
;
195 s
->frame
.data
[0][iy
[3] + 0] = codebook
->y2
;
196 s
->frame
.data
[0][iy
[3] + 1] = codebook
->y2
;
197 if (!s
->palette_video
) {
198 s
->frame
.data
[1][iu
[1]] = codebook
->u
;
199 s
->frame
.data
[2][iv
[1]] = codebook
->v
;
202 s
->frame
.data
[0][iy
[2] + 2] = codebook
->y3
;
203 s
->frame
.data
[0][iy
[2] + 3] = codebook
->y3
;
204 s
->frame
.data
[0][iy
[3] + 2] = codebook
->y3
;
205 s
->frame
.data
[0][iy
[3] + 3] = codebook
->y3
;
206 if (!s
->palette_video
) {
207 s
->frame
.data
[1][iu
[1] + 1] = codebook
->u
;
208 s
->frame
.data
[2][iv
[1] + 1] = codebook
->v
;
211 } else if (flag
& mask
) {
212 if ((data
+ 4) > eod
)
213 return AVERROR_INVALIDDATA
;
215 codebook
= &strip
->v4_codebook
[*data
++];
216 s
->frame
.data
[0][iy
[0] + 0] = codebook
->y0
;
217 s
->frame
.data
[0][iy
[0] + 1] = codebook
->y1
;
218 s
->frame
.data
[0][iy
[1] + 0] = codebook
->y2
;
219 s
->frame
.data
[0][iy
[1] + 1] = codebook
->y3
;
220 if (!s
->palette_video
) {
221 s
->frame
.data
[1][iu
[0]] = codebook
->u
;
222 s
->frame
.data
[2][iv
[0]] = codebook
->v
;
225 codebook
= &strip
->v4_codebook
[*data
++];
226 s
->frame
.data
[0][iy
[0] + 2] = codebook
->y0
;
227 s
->frame
.data
[0][iy
[0] + 3] = codebook
->y1
;
228 s
->frame
.data
[0][iy
[1] + 2] = codebook
->y2
;
229 s
->frame
.data
[0][iy
[1] + 3] = codebook
->y3
;
230 if (!s
->palette_video
) {
231 s
->frame
.data
[1][iu
[0] + 1] = codebook
->u
;
232 s
->frame
.data
[2][iv
[0] + 1] = codebook
->v
;
235 codebook
= &strip
->v4_codebook
[*data
++];
236 s
->frame
.data
[0][iy
[2] + 0] = codebook
->y0
;
237 s
->frame
.data
[0][iy
[2] + 1] = codebook
->y1
;
238 s
->frame
.data
[0][iy
[3] + 0] = codebook
->y2
;
239 s
->frame
.data
[0][iy
[3] + 1] = codebook
->y3
;
240 if (!s
->palette_video
) {
241 s
->frame
.data
[1][iu
[1]] = codebook
->u
;
242 s
->frame
.data
[2][iv
[1]] = codebook
->v
;
245 codebook
= &strip
->v4_codebook
[*data
++];
246 s
->frame
.data
[0][iy
[2] + 2] = codebook
->y0
;
247 s
->frame
.data
[0][iy
[2] + 3] = codebook
->y1
;
248 s
->frame
.data
[0][iy
[3] + 2] = codebook
->y2
;
249 s
->frame
.data
[0][iy
[3] + 3] = codebook
->y3
;
250 if (!s
->palette_video
) {
251 s
->frame
.data
[1][iu
[1] + 1] = codebook
->u
;
252 s
->frame
.data
[2][iv
[1] + 1] = codebook
->v
;
258 iy
[0] += 4; iy
[1] += 4;
259 iy
[2] += 4; iy
[3] += 4;
260 iu
[0] += 2; iu
[1] += 2;
261 iv
[0] += 2; iv
[1] += 2;
268 static int cinepak_decode_strip (CinepakContext
*s
,
269 cvid_strip
*strip
, const uint8_t *data
, int size
)
271 const uint8_t *eod
= (data
+ size
);
272 int chunk_id
, chunk_size
;
274 /* coordinate sanity checks */
275 if (strip
->x2
> s
->width
||
276 strip
->y2
> s
->height
||
277 strip
->x1
>= strip
->x2
|| strip
->y1
>= strip
->y2
)
278 return AVERROR_INVALIDDATA
;
280 while ((data
+ 4) <= eod
) {
282 chunk_size
= AV_RB24 (&data
[1]) - 4;
284 return AVERROR_INVALIDDATA
;
287 chunk_size
= ((data
+ chunk_size
) > eod
) ? (eod
- data
) : chunk_size
;
295 cinepak_decode_codebook (strip
->v4_codebook
, chunk_id
,
303 cinepak_decode_codebook (strip
->v1_codebook
, chunk_id
,
310 return cinepak_decode_vectors (s
, strip
, chunk_id
,
317 return AVERROR_INVALIDDATA
;
320 static int cinepak_decode (CinepakContext
*s
)
322 const uint8_t *eod
= (s
->data
+ s
->size
);
323 int i
, result
, strip_size
, frame_flags
, num_strips
;
325 int encoded_buf_size
;
328 return AVERROR_INVALIDDATA
;
330 frame_flags
= s
->data
[0];
331 num_strips
= AV_RB16 (&s
->data
[8]);
332 encoded_buf_size
= AV_RB24(&s
->data
[1]);
334 /* if this is the first frame, check for deviant Sega FILM data */
335 if (s
->sega_film_skip_bytes
== -1) {
336 if (!encoded_buf_size
) {
337 av_log_ask_for_sample(s
->avctx
, "encoded_buf_size is 0");
338 return AVERROR_PATCHWELCOME
;
340 if (encoded_buf_size
!= s
->size
&& (s
->size
% encoded_buf_size
) != 0) {
341 /* If the encoded frame size differs from the frame size as indicated
342 * by the container file, this data likely comes from a Sega FILM/CPK file.
343 * If the frame header is followed by the bytes FE 00 00 06 00 00 then
344 * this is probably one of the two known files that have 6 extra bytes
345 * after the frame header. Else, assume 2 extra bytes. The container
346 * size also cannot be a multiple of the encoded size. */
348 (s
->data
[10] == 0xFE) &&
349 (s
->data
[11] == 0x00) &&
350 (s
->data
[12] == 0x00) &&
351 (s
->data
[13] == 0x06) &&
352 (s
->data
[14] == 0x00) &&
353 (s
->data
[15] == 0x00))
354 s
->sega_film_skip_bytes
= 6;
356 s
->sega_film_skip_bytes
= 2;
358 s
->sega_film_skip_bytes
= 0;
361 s
->data
+= 10 + s
->sega_film_skip_bytes
;
363 num_strips
= FFMIN(num_strips
, MAX_STRIPS
);
365 for (i
=0; i
< num_strips
; i
++) {
366 if ((s
->data
+ 12) > eod
)
367 return AVERROR_INVALIDDATA
;
369 s
->strips
[i
].id
= s
->data
[0];
370 s
->strips
[i
].y1
= y0
;
372 s
->strips
[i
].y2
= y0
+ AV_RB16 (&s
->data
[8]);
373 s
->strips
[i
].x2
= s
->avctx
->width
;
375 strip_size
= AV_RB24 (&s
->data
[1]) - 12;
377 return AVERROR_INVALIDDATA
;
379 strip_size
= ((s
->data
+ strip_size
) > eod
) ? (eod
- s
->data
) : strip_size
;
381 if ((i
> 0) && !(frame_flags
& 0x01)) {
382 memcpy (s
->strips
[i
].v4_codebook
, s
->strips
[i
-1].v4_codebook
,
383 sizeof(s
->strips
[i
].v4_codebook
));
384 memcpy (s
->strips
[i
].v1_codebook
, s
->strips
[i
-1].v1_codebook
,
385 sizeof(s
->strips
[i
].v1_codebook
));
388 result
= cinepak_decode_strip (s
, &s
->strips
[i
], s
->data
, strip_size
);
393 s
->data
+= strip_size
;
394 y0
= s
->strips
[i
].y2
;
399 static av_cold
int cinepak_decode_init(AVCodecContext
*avctx
)
401 CinepakContext
*s
= avctx
->priv_data
;
404 s
->width
= (avctx
->width
+ 3) & ~3;
405 s
->height
= (avctx
->height
+ 3) & ~3;
406 s
->sega_film_skip_bytes
= -1; /* uninitialized state */
408 // check for paletted data
409 if (avctx
->bits_per_coded_sample
!= 8) {
410 s
->palette_video
= 0;
411 avctx
->pix_fmt
= AV_PIX_FMT_YUV420P
;
413 s
->palette_video
= 1;
414 avctx
->pix_fmt
= AV_PIX_FMT_PAL8
;
417 avcodec_get_frame_defaults(&s
->frame
);
422 static int cinepak_decode_frame(AVCodecContext
*avctx
,
423 void *data
, int *got_frame
,
426 const uint8_t *buf
= avpkt
->data
;
427 int ret
= 0, buf_size
= avpkt
->size
;
428 CinepakContext
*s
= avctx
->priv_data
;
433 if ((ret
= ff_reget_buffer(avctx
, &s
->frame
))) {
434 av_log(avctx
, AV_LOG_ERROR
, "reget_buffer() failed\n");
438 if (s
->palette_video
) {
439 const uint8_t *pal
= av_packet_get_side_data(avpkt
, AV_PKT_DATA_PALETTE
, NULL
);
441 s
->frame
.palette_has_changed
= 1;
442 memcpy(s
->pal
, pal
, AVPALETTE_SIZE
);
448 if (s
->palette_video
)
449 memcpy (s
->frame
.data
[1], s
->pal
, AVPALETTE_SIZE
);
451 if ((ret
= av_frame_ref(data
, &s
->frame
)) < 0)
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 av_frame_unref(&s
->frame
);
469 AVCodec ff_cinepak_decoder
= {
471 .type
= AVMEDIA_TYPE_VIDEO
,
472 .id
= AV_CODEC_ID_CINEPAK
,
473 .priv_data_size
= sizeof(CinepakContext
),
474 .init
= cinepak_decode_init
,
475 .close
= cinepak_decode_end
,
476 .decode
= cinepak_decode_frame
,
477 .capabilities
= CODEC_CAP_DR1
,
478 .long_name
= NULL_IF_CONFIG_SMALL("Cinepak"),