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
|
/*
costs per 4 pixels: (# = black)
1 bit:
----
4 bits:
#---
##--
--##
####
5 bits:
---#
#-##
-###
-#--
--#-
6 bits:
#-#-
-##-
###-
#--#
-#-#
##-#
*/
#include <stdio.h>
void LogoPackBits(unsigned char *srcp, unsigned char *destp)
{
unsigned int destbit = 0;
unsigned int destvalue = 0;
unsigned int d = 0;
for (unsigned int s=0; s<1664; s++)
{
if (srcp[s]) destvalue |= 1<<destbit;
if (++destbit == 8)
{
destp[d++] = destvalue;
destbit = 0;
destvalue = 0;
}
}
}
struct LogoPattern
{
unsigned int value;
unsigned int bits;
} logoPatterns[16] =
{
{0x01, 1}, {0x06, 4}, {0x0A, 5}, {0x04, 4},
{0x02, 5}, {0x1E, 6}, {0x16, 6}, {0x06, 6},
{0x06, 5}, {0x1F, 6}, {0x17, 6}, {0x07, 6},
{0x02, 4}, {0x0E, 5}, {0x07, 5}, {0x00, 4},
};
int LogoCompress(unsigned char *src, unsigned char *dst)
{
unsigned int data_out = 0;
unsigned int outbit = 31;
unsigned int outbitcnt = 0;
for (int i=0; i<212; i++)
{
unsigned int data = *src++;
for (int j=0; j<8; j+=4)
{
LogoPattern &lh = logoPatterns[data >> j & 0xF];
outbitcnt += lh.bits;
for (int b=lh.bits-1; b>=0; b--)
{
data_out |= (lh.value >> b & 1) << outbit;
if (outbit == 0)
{
if (outbitcnt <= 156*8)
{
*dst++ = data_out >> 0;
*dst++ = data_out >> 8;
*dst++ = data_out >> 16;
*dst++ = data_out >> 24;
}
outbit = 31;
data_out = 0;
}
else
{
outbit--;
}
}
}
}
if (outbit != 31)
{
if (outbitcnt <= 156*8)
{
*dst++ = data_out >> 0;
*dst++ = data_out >> 8;
*dst++ = data_out >> 16;
*dst++ = data_out >> 24;
}
}
return 156*8 - outbitcnt;
};
void LogoDiff(unsigned char *srcp, unsigned char *dstp)
{
unsigned int *intp_dst = (unsigned int *)dstp;
*intp_dst++ = 0xD0 << 8 | 0x80 | 2; // header
unsigned short *shortp_dst = (unsigned short *)intp_dst;
unsigned short *shortp_src = (unsigned short *)srcp;
unsigned short prev = 0;
for (unsigned int i=0; i<0xD0; i+=2)
{
*shortp_dst++ = *shortp_src - prev;
prev = *shortp_src++;
}
}
int LogoConvert(unsigned char *srcp, unsigned char *dstp, unsigned char white)
{
// convert to tiles
unsigned char tiles[1664];
for (int ty=0; ty<2; ty++)
{
for (int y=0; y<8; y++)
{
for (int tx=0; tx<13; tx++)
{
for (int x=0; x<8; x++)
{
tiles[(ty*13 + tx)*64 + y*8 + x] = (*srcp++ == white) ? 0 : 1;
}
}
}
}
// bitpack
unsigned char bitpacked[1664/8];
LogoPackBits(tiles, bitpacked);
// diff
unsigned char diffed[4 + 1664/8];
LogoDiff(bitpacked, diffed);
// compress
int r = LogoCompress(diffed, dstp);
if (r < 0)
{
fprintf(stderr, "Compressed logo is %u bit(s) too big. Please simplify.\n", -r);
return -1;
}
return 0;
}
|
