2 * Beam Software VB decoder
3 * Copyright (c) 2007 Konstantin Shishkov
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
31 #include "bytestream.h"
38 VB_HAS_PALETTE
= 0x10,
42 typedef struct VBDecContext
{
43 AVCodecContext
*avctx
;
45 uint8_t *frame
, *prev_frame
;
46 uint32_t pal
[AVPALETTE_COUNT
];
47 GetByteContext stream
;
50 static const uint16_t vb_patterns
[64] = {
51 0x0660, 0xFF00, 0xCCCC, 0xF000, 0x8888, 0x000F, 0x1111, 0xFEC8,
52 0x8CEF, 0x137F, 0xF731, 0xC800, 0x008C, 0x0013, 0x3100, 0xCC00,
53 0x00CC, 0x0033, 0x3300, 0x0FF0, 0x6666, 0x00F0, 0x0F00, 0x2222,
54 0x4444, 0xF600, 0x8CC8, 0x006F, 0x1331, 0x318C, 0xC813, 0x33CC,
55 0x6600, 0x0CC0, 0x0066, 0x0330, 0xF900, 0xC88C, 0x009F, 0x3113,
56 0x6000, 0x0880, 0x0006, 0x0110, 0xCC88, 0xFC00, 0x00CF, 0x88CC,
57 0x003F, 0x1133, 0x3311, 0xF300, 0x6FF6, 0x0603, 0x08C6, 0x8C63,
58 0xC631, 0x6310, 0xC060, 0x0136, 0x136C, 0x36C8, 0x6C80, 0x324C
61 static void vb_decode_palette(VBDecContext
*c
, int data_size
)
65 start
= bytestream2_get_byte(&c
->stream
);
66 size
= (bytestream2_get_byte(&c
->stream
) - 1) & 0xFF;
67 if (start
+ size
> 255) {
68 av_log(c
->avctx
, AV_LOG_ERROR
, "Palette change runs beyond entry 256\n");
71 if (size
*3+2 > data_size
) {
72 av_log(c
->avctx
, AV_LOG_ERROR
, "Palette data runs beyond chunk size\n");
75 for (i
= start
; i
<= start
+ size
; i
++)
76 c
->pal
[i
] = 0xFFU
<< 24 | bytestream2_get_be24(&c
->stream
);
79 static inline int check_pixel(uint8_t *buf
, uint8_t *start
, uint8_t *end
)
81 return buf
>= start
&& buf
< end
;
84 static inline int check_line(uint8_t *buf
, uint8_t *start
, uint8_t *end
)
86 return buf
>= start
&& (buf
+ 4) <= end
;
89 static int vb_decode_framedata(VBDecContext
*c
, int offset
)
93 int blk
, blocks
, t
, blk2
;
97 const int width
= c
->avctx
->width
;
98 uint8_t *pstart
= c
->prev_frame
;
99 uint8_t *pend
= c
->prev_frame
+ width
*c
->avctx
->height
;
103 prev
= c
->prev_frame
+ offset
;
106 blocks
= (c
->avctx
->width
>> 2) * (c
->avctx
->height
>> 2);
108 for (blk
= 0; blk
< blocks
; blk
++) {
110 blocktypes
= bytestream2_get_byte(&g
);
112 switch (blocktypes
& 0xC0) {
114 for (y
= 0; y
< 4; y
++)
115 if (check_line(prev
+ y
*width
, pstart
, pend
))
116 memcpy(cur
+ y
*width
, prev
+ y
*width
, 4);
118 memset(cur
+ y
*width
, 0, 4);
121 t
= bytestream2_get_byte(&g
);
122 if (!t
) { //raw block
123 if (bytestream2_get_bytes_left(&g
) < 16) {
124 av_log(c
->avctx
, AV_LOG_ERROR
, "Insufficient data\n");
125 return AVERROR_INVALIDDATA
;
127 for (y
= 0; y
< 4; y
++)
128 bytestream2_get_buffer(&g
, cur
+ y
* width
, 4);
129 } else { // motion compensation
130 x
= ((t
& 0xF)^8) - 8;
131 y
= ((t
>> 4) ^8) - 8;
133 for (y
= 0; y
< 4; y
++)
134 if (check_line(prev
+ t
+ y
*width
, pstart
, pend
))
135 memcpy(cur
+ y
*width
, prev
+ t
+ y
*width
, 4);
137 memset(cur
+ y
*width
, 0, 4);
141 t
= bytestream2_get_byte(&g
);
142 for (y
= 0; y
< 4; y
++)
143 memset(cur
+ y
*width
, t
, 4);
145 case 0xC0: // pattern fill
146 t
= bytestream2_get_byte(&g
);
148 pattern
= vb_patterns
[t
& 0x3F];
151 a
= bytestream2_get_byte(&g
);
152 b
= bytestream2_get_byte(&g
);
153 for (y
= 0; y
< 4; y
++)
154 for (x
= 0; x
< 4; x
++, pattern
>>= 1)
155 cur
[x
+ y
*width
] = (pattern
& 1) ? b
: a
;
160 a
= bytestream2_get_byte(&g
);
161 for (y
= 0; y
< 4; y
++)
162 for (x
= 0; x
< 4; x
++, pattern
>>= 1)
163 if (pattern
& 1 && check_pixel(prev
+ x
+ y
*width
, pstart
, pend
))
164 cur
[x
+ y
*width
] = prev
[x
+ y
*width
];
166 cur
[x
+ y
*width
] = a
;
169 av_log(c
->avctx
, AV_LOG_ERROR
, "Invalid opcode seen @%d\n", blk
);
170 return AVERROR_INVALIDDATA
;
178 if (blk2
== (width
>> 2)) {
187 static int decode_frame(AVCodecContext
*avctx
, void *data
, int *got_frame
,
190 VBDecContext
* const c
= avctx
->priv_data
;
191 AVFrame
*frame
= data
;
192 uint8_t *outptr
, *srcptr
;
198 bytestream2_init(&c
->stream
, avpkt
->data
, avpkt
->size
);
200 if ((ret
= ff_get_buffer(avctx
, frame
, 0)) < 0)
203 flags
= bytestream2_get_le16(&c
->stream
);
205 if (flags
& VB_HAS_GMC
) {
206 i
= (int16_t)bytestream2_get_le16(&c
->stream
);
207 j
= (int16_t)bytestream2_get_le16(&c
->stream
);
208 offset
= i
+ j
* avctx
->width
;
210 if (flags
& VB_HAS_VIDEO
) {
211 size
= bytestream2_get_le32(&c
->stream
);
212 if(size
> bytestream2_get_bytes_left(&c
->stream
)+4 || size
<4){
213 av_log(avctx
, AV_LOG_ERROR
, "Frame size invalid\n");
216 vb_decode_framedata(c
, offset
);
217 bytestream2_skip(&c
->stream
, size
- 4);
219 if (flags
& VB_HAS_PALETTE
) {
220 size
= bytestream2_get_le32(&c
->stream
);
221 vb_decode_palette(c
, size
);
224 memcpy(frame
->data
[1], c
->pal
, AVPALETTE_SIZE
);
225 frame
->palette_has_changed
= flags
& VB_HAS_PALETTE
;
227 outptr
= frame
->data
[0];
230 for (i
= 0; i
< avctx
->height
; i
++) {
231 memcpy(outptr
, srcptr
, avctx
->width
);
232 srcptr
+= avctx
->width
;
233 outptr
+= frame
->linesize
[0];
236 FFSWAP(uint8_t*, c
->frame
, c
->prev_frame
);
240 /* always report that the buffer was completely consumed */
244 static av_cold
int decode_init(AVCodecContext
*avctx
)
246 VBDecContext
* const c
= avctx
->priv_data
;
249 avctx
->pix_fmt
= AV_PIX_FMT_PAL8
;
251 c
->frame
= av_mallocz(avctx
->width
* avctx
->height
);
252 c
->prev_frame
= av_mallocz(avctx
->width
* avctx
->height
);
257 static av_cold
int decode_end(AVCodecContext
*avctx
)
259 VBDecContext
*c
= avctx
->priv_data
;
262 av_freep(&c
->prev_frame
);
267 AVCodec ff_vb_decoder
= {
269 .long_name
= NULL_IF_CONFIG_SMALL("Beam Software VB"),
270 .type
= AVMEDIA_TYPE_VIDEO
,
271 .id
= AV_CODEC_ID_VB
,
272 .priv_data_size
= sizeof(VBDecContext
),
275 .decode
= decode_frame
,
276 .capabilities
= CODEC_CAP_DR1
,