/
image.go
224 lines (198 loc) · 6.81 KB
/
image.go
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
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
// Copyright Terence J. Boldt (c)2021-2023
// Use of this source code is governed by an MIT
// license that can be found in the LICENSE file.
// This file provides access to read, write and delete
// files on a ProDOS drive image
package prodos
import (
"bytes"
"fmt"
"image"
"image/color"
// force import jpeg support by init only
_ "image/jpeg"
// force import png support by init only
_ "image/png"
"golang.org/x/image/draw"
)
// 10 PRINT CHR$ (4)"open offsets"
// 20 PRINT CHR$ (4)"write offsets"
// 30 PRINT "offsets := [192]int{";
// 40 FOR Y = 0 TO 191
// 50 HPLOT 0,Y
// 60 PRINT ( PEEK (39) * 256 + PEEK (38)) - 8192;
// 70 IF Y < 191 THEN PRINT ", ";
// 80 NEXT
// 90 PRINT "}"
// 100 PRINT CHR$ (4)"close offsets"
var offsets = []int{0, 1024, 2048, 3072, 4096, 5120, 6144, 7168, 128, 1152, 2176, 3200, 4224, 5248, 6272, 7296, 256, 1280, 2304, 3328, 4352, 5376, 6400, 7424, 384, 1408, 2432, 3456, 4480, 5504, 6528, 7552, 512, 1536, 2560, 3584, 4608, 5632, 6656, 7680, 640, 1664, 2688, 3712, 4736, 5760, 6784, 7808, 768, 1792, 2816, 3840, 4864, 5888, 6912, 7936, 896, 1920, 2944, 3968, 4992, 6016, 7040, 8064, 40, 1064, 2088, 3112, 4136, 5160, 6184, 7208, 168, 1192, 2216, 3240, 4264, 5288, 6312, 7336, 296, 1320, 2344, 3368, 4392, 5416, 6440, 7464, 424, 1448, 2472, 3496, 4520, 5544, 6568, 7592, 552, 1576, 2600, 3624, 4648, 5672, 6696, 7720, 680, 1704, 2728, 3752, 4776, 5800, 6824, 7848, 808, 1832, 2856, 3880, 4904, 5928, 6952, 7976, 936, 1960, 2984, 4008, 5032, 6056, 7080, 8104, 80, 1104, 2128, 3152, 4176, 5200, 6224, 7248, 208, 1232, 2256, 3280, 4304, 5328, 6352, 7376, 336, 1360, 2384, 3408, 4432, 5456, 6480, 7504, 464, 1488, 2512, 3536, 4560, 5584, 6608, 7632, 592, 1616, 2640, 3664, 4688, 5712, 6736, 7760, 720, 1744, 2768, 3792, 4816, 5840, 6864, 7888, 848, 1872, 2896, 3920, 4944, 5968, 6992, 8016, 976, 2000, 3024, 4048, 5072, 6096, 7120, 8144}
var pixel = []byte{1, 2, 4, 8, 16, 32, 64}
// ConvertImageToHiResMonochrome converts jpeg and png images to Apple II hi-res monochrome
func ConvertImageToHiResMonochrome(imageBytes []byte) []byte {
img, _, err := image.Decode(bytes.NewReader(imageBytes))
if err != nil {
fmt.Printf("%s\n", err)
return nil
}
a2imgSize := image.Rect(0, 0, 280, 192)
a2img := image.NewPaletted(a2imgSize, []color.Color{
color.Black,
color.White,
})
a2monoImgSize := image.Rect(0, 0, 280, 192)
scaledImg := image.NewRGBA(a2monoImgSize)
draw.BiLinear.Scale(scaledImg, a2monoImgSize, img, img.Bounds(), draw.Over, nil)
draw.FloydSteinberg.Draw(a2img, a2monoImgSize, scaledImg, image.Point{})
hires := make([]byte, 8192)
for y := a2img.Bounds().Min.Y; y < a2img.Bounds().Max.Y; y++ {
for x := a2img.Bounds().Min.X; x < a2img.Bounds().Max.X; x++ {
if a2img.At(x, y) == color.White {
hires[offsets[y]+x/7] |= pixel[x%7] | 128
}
}
}
return hires
}
// ConvertImageToHiResColour converts jpeg and png images to Apple II hi-res colour
func ConvertImageToHiResColour(imageBytes []byte) []byte {
img, _, err := image.Decode(bytes.NewReader(imageBytes))
if err != nil {
fmt.Printf("%s\n", err)
return nil
}
a2colourImgSize := image.Rect(0, 0, 140, 192)
black := color.NRGBA{0, 0, 0, 255}
green := color.NRGBA{20, 245, 60, 255}
purple := color.NRGBA{255, 68, 253, 255}
white := color.NRGBA{255, 255, 255, 255}
orange := color.NRGBA{255, 106, 60, 255}
blue := color.NRGBA{20, 207, 253, 255}
a2img := image.NewPaletted(a2colourImgSize, []color.Color{
black,
green,
purple,
white,
orange,
blue,
})
scaledImg := image.NewRGBA(a2colourImgSize)
draw.BiLinear.Scale(scaledImg, a2colourImgSize, img, img.Bounds(), draw.Over, nil)
draw.FloydSteinberg.Draw(a2img, a2colourImgSize, scaledImg, image.Point{})
hires := make([]byte, 8192)
for y := a2img.Bounds().Min.Y; y < a2img.Bounds().Max.Y; y++ {
for x7 := a2img.Bounds().Min.X; x7 < a2img.Bounds().Max.X; x7 += 7 {
switch a2img.At(x7, y) {
case green:
hires[offsets[y]+x7*2/7] = 2
case purple:
hires[offsets[y]+x7*2/7] = 1
case orange:
hires[offsets[y]+x7*2/7] = 2
hires[offsets[y]+x7*2/7] |= 0x80
case blue:
hires[offsets[y]+x7*2/7] = 1
hires[offsets[y]+x7*2/7] |= 0x80
case white:
hires[offsets[y]+x7*2/7] = 3
}
switch a2img.At(x7+1, y) {
case green:
hires[offsets[y]+x7*2/7] |= 8
hires[offsets[y]+x7*2/7] &= 0x7F
case purple:
hires[offsets[y]+x7*2/7] |= 4
hires[offsets[y]+x7*2/7] &= 0x7F
case orange:
hires[offsets[y]+x7*2/7] |= 8
hires[offsets[y]+x7*2/7] |= 0x80
case blue:
hires[offsets[y]+x7*2/7] |= 4
hires[offsets[y]+x7*2/7] |= 0x80
case white:
hires[offsets[y]+x7*2/7] |= 12
}
switch a2img.At(x7+2, y) {
case green:
hires[offsets[y]+x7*2/7] |= 32
hires[offsets[y]+x7*2/7] &= 0x7F
case purple:
hires[offsets[y]+x7*2/7] |= 16
hires[offsets[y]+x7*2/7] &= 0x7F
case orange:
hires[offsets[y]+x7*2/7] |= 32
hires[offsets[y]+x7*2/7] |= 0x80
case blue:
hires[offsets[y]+x7*2/7] |= 16
hires[offsets[y]+x7*2/7] |= 0x80
case white:
hires[offsets[y]+x7*2/7] |= 48
}
switch a2img.At(x7+3, y) {
case green:
hires[offsets[y]+x7*2/7+1] |= 1
hires[offsets[y]+x7*2/7+1] &= 0x7F
case purple:
hires[offsets[y]+x7*2/7] |= 64
hires[offsets[y]+x7*2/7] &= 0x7F
case orange:
hires[offsets[y]+x7*2/7+1] |= 1
hires[offsets[y]+x7*2/7+1] |= 0x80
case blue:
hires[offsets[y]+x7*2/7] |= 64
hires[offsets[y]+x7*2/7] |= 0x80
case white:
hires[offsets[y]+x7*2/7] |= 64
hires[offsets[y]+x7*2/7+1] |= 1
}
switch a2img.At(x7+4, y) {
case green:
hires[offsets[y]+x7*2/7+1] |= 4
hires[offsets[y]+x7*2/7+1] &= 0x7F
case purple:
hires[offsets[y]+x7*2/7+1] |= 2
hires[offsets[y]+x7*2/7+1] &= 0x7F
case orange:
hires[offsets[y]+x7*2/7+1] |= 4
hires[offsets[y]+x7*2/7+1] |= 0x80
case blue:
hires[offsets[y]+x7*2/7+1] |= 2
hires[offsets[y]+x7*2/7+1] |= 0x80
case white:
hires[offsets[y]+x7*2/7+1] |= 6
}
switch a2img.At(x7+5, y) {
case green:
hires[offsets[y]+x7*2/7+1] |= 16
hires[offsets[y]+x7*2/7+1] &= 0x7F
case purple:
hires[offsets[y]+x7*2/7+1] |= 8
hires[offsets[y]+x7*2/7+1] &= 0x7F
case orange:
hires[offsets[y]+x7*2/7+1] |= 16
hires[offsets[y]+x7*2/7+1] |= 0x80
case blue:
hires[offsets[y]+x7*2/7+1] |= 8
hires[offsets[y]+x7*2/7+1] |= 0x80
case white:
hires[offsets[y]+x7*2/7+1] |= 24
}
switch a2img.At(x7+6, y) {
case green:
hires[offsets[y]+x7*2/7+1] |= 64
hires[offsets[y]+x7*2/7+1] &= 0x7F
case purple:
hires[offsets[y]+x7*2/7+1] |= 32
hires[offsets[y]+x7*2/7+1] &= 0x7F
case orange:
hires[offsets[y]+x7*2/7+1] |= 64
hires[offsets[y]+x7*2/7+1] |= 0x80
case blue:
hires[offsets[y]+x7*2/7+1] |= 32
hires[offsets[y]+x7*2/7+1] |= 0x80
case white:
hires[offsets[y]+x7*2/7+1] |= 96
}
}
}
return hires
}