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
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2016 MediaTek Inc.
* Author: Ming Hsiu Tsai <minghsiu.tsai@mediatek.com>
* Rick Chang <rick.chang@mediatek.com>
*/
#include <linux/kernel.h>
#include <linux/videodev2.h>
#include <media/jpeg.h>
#include "mtk_jpeg_dec_parse.h"
struct mtk_jpeg_stream {
u8 *addr;
u32 size;
u32 curr;
};
static int read_byte(struct mtk_jpeg_stream *stream)
{
if (stream->curr >= stream->size)
return -1;
return stream->addr[stream->curr++];
}
static int read_word_be(struct mtk_jpeg_stream *stream, u32 *word)
{
u32 temp;
int byte;
byte = read_byte(stream);
if (byte == -1)
return -1;
temp = byte << 8;
byte = read_byte(stream);
if (byte == -1)
return -1;
*word = (u32)byte | temp;
return 0;
}
static void read_skip(struct mtk_jpeg_stream *stream, long len)
{
if (len <= 0)
return;
while (len--)
read_byte(stream);
}
static bool mtk_jpeg_do_parse(struct mtk_jpeg_dec_param *param, u8 *src_addr_va,
u32 src_size)
{
bool notfound = true;
struct mtk_jpeg_stream stream;
stream.addr = src_addr_va;
stream.size = src_size;
stream.curr = 0;
while (notfound) {
int i, length, byte;
u32 word;
byte = read_byte(&stream);
if (byte == -1)
return false;
if (byte != 0xff)
continue;
do
byte = read_byte(&stream);
while (byte == 0xff);
if (byte == -1)
return false;
if (byte == 0)
continue;
length = 0;
switch (byte) {
case JPEG_MARKER_SOF0:
/* length */
if (read_word_be(&stream, &word))
break;
/* precision */
if (read_byte(&stream) == -1)
break;
if (read_word_be(&stream, &word))
break;
param->pic_h = word;
if (read_word_be(&stream, &word))
break;
param->pic_w = word;
param->comp_num = read_byte(&stream);
if (param->comp_num != 1 && param->comp_num != 3)
break;
for (i = 0; i < param->comp_num; i++) {
param->comp_id[i] = read_byte(&stream);
if (param->comp_id[i] == -1)
break;
/* sampling */
byte = read_byte(&stream);
if (byte == -1)
break;
param->sampling_w[i] = (byte >> 4) & 0x0F;
param->sampling_h[i] = byte & 0x0F;
param->qtbl_num[i] = read_byte(&stream);
if (param->qtbl_num[i] == -1)
break;
}
notfound = !(i == param->comp_num);
break;
case JPEG_MARKER_RST ... JPEG_MARKER_RST + 7:
case JPEG_MARKER_SOI:
case JPEG_MARKER_EOI:
case JPEG_MARKER_TEM:
break;
default:
if (read_word_be(&stream, &word))
break;
length = (long)word - 2;
read_skip(&stream, length);
break;
}
}
return !notfound;
}
bool mtk_jpeg_parse(struct mtk_jpeg_dec_param *param, u8 *src_addr_va,
u32 src_size)
{
if (!mtk_jpeg_do_parse(param, src_addr_va, src_size))
return false;
if (mtk_jpeg_dec_fill_param(param))
return false;
return true;
}
|
