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
|
use crate::{
block::Block,
frame::Frame,
helpers::{pixel::Pixel, vector::Vec2},
view::View,
};
use rustdct::DctPlanner;
pub fn compress_block(block: &mut Block, size: Vec2<usize>) {
match block {
Block::Literal(p) => {
let comp = lit_compress(size.x, size.y, &p);
*block = Block::CompressedLiteral(comp)
}
Block::Split(box [a, b]) => {
let vert = size.x > size.y;
compress_block(
a,
if vert {
Vec2 {
x: size.x / 2,
y: size.y,
}
} else {
Vec2 {
x: size.x,
y: size.y / 2,
}
},
);
compress_block(
b,
if vert {
Vec2 {
x: size.x - size.x / 2,
y: size.y,
}
} else {
Vec2 {
x: size.x,
y: size.y - size.y / 2,
}
},
);
}
_ => (),
}
}
pub fn lit_compress(w: usize, h: usize, pixels: &[Pixel]) -> Vec<u8> {
let mut out = vec![];
for ci in 0..3 {
let mut ch = vec![0.; w * h];
for y in 0..h {
for x in 0..w {
let p = pixels[x + y * w];
ch[x + y * w] = match ci {
0 => p.r,
1 => p.g,
2 => p.b,
_ => unreachable!(),
} as f32
}
}
norm_dct_channel(w, h, &mut ch);
for i in 0..w * h {
out.extend(unsafe { std::mem::transmute::<_, [u8; 4]>(ch[i]) });
}
}
out
}
pub fn lit_decompress(compressed: &[u8], mut target: View<&mut Frame>) {
let (w, h) = (target.size.x as usize, target.size.y as usize);
for ci in 0..3 {
let mut ch = compressed[ci * w * h..(ci + 1) * w * h]
.chunks_exact(4)
.map(|v| unsafe {
std::mem::transmute::<_, f32>(TryInto::<[u8; 4]>::try_into(v).unwrap())
})
.collect::<Vec<_>>();
norm_idct_channel(w, h, &mut ch);
for y in 0..h {
for x in 0..w {
let p = &mut target[Vec2 {
x: x as isize,
y: y as isize,
}];
*(match ci {
0 => &mut p.r,
1 => &mut p.g,
2 => &mut p.b,
_ => unreachable!(),
}) = ch[x + y * w] as u8
}
}
}
}
fn norm_dct_channel(w: usize, h: usize, values: &mut [f32]) {
let d = DctPlanner::new().plan_dct2(w);
let mut temp = vec![0.; d.get_scratch_len()];
for c in values.chunks_exact_mut(w) {
d.process_dct2_with_scratch(c, &mut temp)
}
let mut values_trans = transpose(w, h, values);
let d = DctPlanner::new().plan_dct2(h);
let mut temp = vec![0.; d.get_scratch_len()];
for c in values_trans.chunks_exact_mut(h) {
d.process_dct2_with_scratch(c, &mut temp)
}
let scale = 2. / (w as f32 * h as f32).sqrt();
for (i, v) in values_trans.iter().enumerate() {
values[i] = *v * scale * 127.0
}
}
fn norm_idct_channel(h: usize, w: usize, values: &mut [f32]) {
let scale = 2. / (w as f32 * h as f32).sqrt();
for v in values.iter_mut() {
*v /= scale * 127.0
}
let d = DctPlanner::new().plan_dct2(w);
let mut temp = vec![0.; d.get_scratch_len()];
for c in values.chunks_exact_mut(w) {
d.process_dct3_with_scratch(c, &mut temp)
}
let mut values_trans = transpose(w, h, values);
let d = DctPlanner::new().plan_dct2(h);
let mut temp = vec![0.; d.get_scratch_len()];
for c in values_trans.chunks_exact_mut(h) {
d.process_dct3_with_scratch(c, &mut temp)
}
values.copy_from_slice(&values_trans)
}
fn transpose(w: usize, h: usize, values: &[f32]) -> Vec<f32> {
let mut io = 0;
let mut it;
let mut transposed = vec![0.; values.len()];
for row in 0..h {
it = row;
for _ in 0..w {
transposed[it] = values[io];
io += 1;
it += h;
}
}
transposed
}
|
