1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
/*
* AVS video decoder.
* Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avcodec.h"
#include "codec_internal.h"
#include "get_bits.h"
#include "internal.h"
typedef struct AvsContext {
AVFrame *frame;
} AvsContext;
typedef enum {
AVS_VIDEO = 0x01,
AVS_AUDIO = 0x02,
AVS_PALETTE = 0x03,
AVS_GAME_DATA = 0x04,
} AvsBlockType;
typedef enum {
AVS_I_FRAME = 0x00,
AVS_P_FRAME_3X3 = 0x01,
AVS_P_FRAME_2X2 = 0x02,
AVS_P_FRAME_2X3 = 0x03,
} AvsVideoSubType;
static int
avs_decode_frame(AVCodecContext * avctx,
void *data, int *got_frame, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
const uint8_t *buf_end = avpkt->data + avpkt->size;
int buf_size = avpkt->size;
AvsContext *const avs = avctx->priv_data;
AVFrame *picture = data;
AVFrame *const p = avs->frame;
const uint8_t *table, *vect;
uint8_t *out;
int i, j, x, y, stride, ret, vect_w = 3, vect_h = 3;
AvsVideoSubType sub_type;
AvsBlockType type;
GetBitContext change_map = {0}; //init to silence warning
if ((ret = ff_reget_buffer(avctx, p, 0)) < 0)
return ret;
p->pict_type = AV_PICTURE_TYPE_P;
p->key_frame = 0;
out = p->data[0];
stride = p->linesize[0];
if (buf_end - buf < 4)
return AVERROR_INVALIDDATA;
sub_type = buf[0];
type = buf[1];
buf += 4;
if (type == AVS_PALETTE) {
int first, last;
uint32_t *pal = (uint32_t *) p->data[1];
first = AV_RL16(buf);
last = first + AV_RL16(buf + 2);
if (first >= 256 || last > 256 || buf_end - buf < 4 + 4 + 3 * (last - first))
return AVERROR_INVALIDDATA;
buf += 4;
for (i=first; i<last; i++, buf+=3) {
pal[i] = (buf[0] << 18) | (buf[1] << 10) | (buf[2] << 2);
pal[i] |= 0xFFU << 24 | (pal[i] >> 6) & 0x30303;
}
sub_type = buf[0];
type = buf[1];
buf += 4;
}
if (type != AVS_VIDEO)
return AVERROR_INVALIDDATA;
switch (sub_type) {
case AVS_I_FRAME:
p->pict_type = AV_PICTURE_TYPE_I;
p->key_frame = 1;
case AVS_P_FRAME_3X3:
vect_w = 3;
vect_h = 3;
break;
case AVS_P_FRAME_2X2:
vect_w = 2;
vect_h = 2;
break;
case AVS_P_FRAME_2X3:
vect_w = 2;
vect_h = 3;
break;
default:
return AVERROR_INVALIDDATA;
}
if (buf_end - buf < 256 * vect_w * vect_h)
return AVERROR_INVALIDDATA;
table = buf + (256 * vect_w * vect_h);
if (sub_type != AVS_I_FRAME) {
int map_size = ((318 / vect_w + 7) / 8) * (198 / vect_h);
if (buf_end - table < map_size)
return AVERROR_INVALIDDATA;
init_get_bits(&change_map, table, map_size * 8);
table += map_size;
}
for (y=0; y<198; y+=vect_h) {
for (x=0; x<318; x+=vect_w) {
if (sub_type == AVS_I_FRAME || get_bits1(&change_map)) {
if (buf_end - table < 1)
return AVERROR_INVALIDDATA;
vect = &buf[*table++ * (vect_w * vect_h)];
for (j=0; j<vect_w; j++) {
out[(y + 0) * stride + x + j] = vect[(0 * vect_w) + j];
out[(y + 1) * stride + x + j] = vect[(1 * vect_w) + j];
if (vect_h == 3)
out[(y + 2) * stride + x + j] =
vect[(2 * vect_w) + j];
}
}
}
if (sub_type != AVS_I_FRAME)
align_get_bits(&change_map);
}
if ((ret = av_frame_ref(picture, p)) < 0)
return ret;
*got_frame = 1;
return buf_size;
}
static av_cold int avs_decode_init(AVCodecContext * avctx)
{
AvsContext *s = avctx->priv_data;
s->frame = av_frame_alloc();
if (!s->frame)
return AVERROR(ENOMEM);
avctx->pix_fmt = AV_PIX_FMT_PAL8;
return ff_set_dimensions(avctx, 318, 198);
}
static av_cold int avs_decode_end(AVCodecContext *avctx)
{
AvsContext *s = avctx->priv_data;
av_frame_free(&s->frame);
return 0;
}
const FFCodec ff_avs_decoder = {
.p.name = "avs",
.p.long_name = NULL_IF_CONFIG_SMALL("AVS (Audio Video Standard) video"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_AVS,
.priv_data_size = sizeof(AvsContext),
.init = avs_decode_init,
.decode = avs_decode_frame,
.close = avs_decode_end,
.p.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};
|