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
|
/*
* ATI VCR1 codec
* Copyright (c) 2003 Michael Niedermayer
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* ATI VCR1 codec
*/
#include "avcodec.h"
#include "internal.h"
#include "libavutil/internal.h"
typedef struct VCR1Context {
int delta[16];
int offset[4];
} VCR1Context;
static av_cold int vcr1_decode_init(AVCodecContext *avctx)
{
avctx->pix_fmt = AV_PIX_FMT_YUV410P;
if (avctx->width & 7) {
av_log(avctx, AV_LOG_ERROR, "Width %d is not divisble by 8.\n", avctx->width);
return AVERROR_INVALIDDATA;
}
return 0;
}
static int vcr1_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
VCR1Context *const a = avctx->priv_data;
AVFrame *const p = data;
const uint8_t *bytestream = buf;
int i, x, y, ret;
if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
p->pict_type = AV_PICTURE_TYPE_I;
p->key_frame = 1;
if (buf_size < 32)
goto packet_small;
for (i = 0; i < 16; i++) {
a->delta[i] = *bytestream++;
bytestream++;
buf_size--;
}
for (y = 0; y < avctx->height; y++) {
int offset;
uint8_t *luma = &p->data[0][y * p->linesize[0]];
if ((y & 3) == 0) {
uint8_t *cb = &p->data[1][(y >> 2) * p->linesize[1]];
uint8_t *cr = &p->data[2][(y >> 2) * p->linesize[2]];
if (buf_size < 4 + avctx->width)
goto packet_small;
for (i = 0; i < 4; i++)
a->offset[i] = *bytestream++;
buf_size -= 4;
offset = a->offset[0] - a->delta[bytestream[2] & 0xF];
for (x = 0; x < avctx->width; x += 4) {
luma[0] = offset += a->delta[bytestream[2] & 0xF];
luma[1] = offset += a->delta[bytestream[2] >> 4];
luma[2] = offset += a->delta[bytestream[0] & 0xF];
luma[3] = offset += a->delta[bytestream[0] >> 4];
luma += 4;
*cb++ = bytestream[3];
*cr++ = bytestream[1];
bytestream += 4;
buf_size -= 4;
}
} else {
if (buf_size < avctx->width / 2)
goto packet_small;
offset = a->offset[y & 3] - a->delta[bytestream[2] & 0xF];
for (x = 0; x < avctx->width; x += 8) {
luma[0] = offset += a->delta[bytestream[2] & 0xF];
luma[1] = offset += a->delta[bytestream[2] >> 4];
luma[2] = offset += a->delta[bytestream[3] & 0xF];
luma[3] = offset += a->delta[bytestream[3] >> 4];
luma[4] = offset += a->delta[bytestream[0] & 0xF];
luma[5] = offset += a->delta[bytestream[0] >> 4];
luma[6] = offset += a->delta[bytestream[1] & 0xF];
luma[7] = offset += a->delta[bytestream[1] >> 4];
luma += 8;
bytestream += 4;
buf_size -= 4;
}
}
}
*got_frame = 1;
return buf_size;
packet_small:
av_log(avctx, AV_LOG_ERROR, "Input packet too small.\n");
return AVERROR_INVALIDDATA;
}
AVCodec ff_vcr1_decoder = {
.name = "vcr1",
.long_name = NULL_IF_CONFIG_SMALL("ATI VCR1"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_VCR1,
.priv_data_size = sizeof(VCR1Context),
.init = vcr1_decode_init,
.decode = vcr1_decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
};
|
