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
|
/*
* Copyright 2022-2023 Frederico de Oliveira Linhares
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "qoi.hpp"
#include <array>
#include <fstream>
#include "../binary_reader.hpp"
namespace
{
const char MAGIC[]{"qoif"};
const int HEADER_SIZE{14};
const uint8_t PADDING[8]{0,0,0,0,0,0,0,1};
const unsigned int PIXELS_MAX{400000000};
const int OP_INDEX{0b00000000};
const int OP_DIFF {0b01000000};
const int OP_LUMA {0b10000000};
const int OP_RUN {0b11000000};
const int OP_RGB {0b11111110};
const int OP_RGBA {0b11111111};
const int MASK_2_BITS{0b11000000};
struct RGBA
{
uint8_t red, green, blue, alpha;
RGBA();
RGBA(uint8_t red, uint8_t green, uint8_t blue, uint8_t alpha);
};
RGBA::RGBA():
red{0},
green{0},
blue{0},
alpha{0}
{
}
RGBA::RGBA(uint8_t red, uint8_t green, uint8_t blue, uint8_t alpha):
red{red},
green{green},
blue{blue},
alpha{alpha}
{
}
struct Pixel
{
union
{
RGBA colors;
uint32_t value;
};
Pixel();
Pixel(uint8_t red, uint8_t green, uint8_t blue, uint8_t alpha);
};
Pixel::Pixel():
colors{}
{
}
Pixel::Pixel(uint8_t red, uint8_t green, uint8_t blue, uint8_t alpha):
colors(red, green, blue, alpha)
{
}
inline int
color_hash(const RGBA &colors)
{
return colors.red*3 + colors.green*5 + colors.blue*7 + colors.alpha*11;
}
}
namespace VK::QOI
{
Image::Image(const char *file_path, uint8_t channels):
channels{channels}
{
if(this->channels != 0 && this->channels != 3 && this->channels != 4)
{
throw std::invalid_argument{"invalid number of channels"};
}
BinaryReader input{file_path};
if(input.size() < HEADER_SIZE + (int)sizeof(PADDING))
{
throw std::runtime_error{"invalid QOI file"};
}
input.read_chars(this->header.magic, 4);
this->header.width = input.read_ui32();
this->header.height = input.read_ui32();
this->header.channels = input.read_ui8();
this->header.colorspace = input.read_ui8();
if(this->header.width == 0 || this->header.height == 0 ||
this->header.channels < 3 || this->header.channels > 4 ||
this->header.colorspace > 1 ||
this->header.height >= PIXELS_MAX / this->header.width)
{
throw std::runtime_error{"QOI file have an invalid header"};
}
if(this->channels == 0) this->channels = this->header.channels;
uint32_t num_pixels{this->header.width * this->header.height};
this->pixels_len = num_pixels * this->channels;
this->pixels = new uint8_t[this->pixels_len];
std::array<Pixel, 64> index;
Pixel pixel(0, 0, 0, 255);
int chunks_len = input.size() - (int)sizeof(PADDING);
/*
This algorithm is based on the original implementation that is in GitHub:
https://github.com/phoboslab/qoi
For information about the QOI image format, see: https://qoiformat.org/
*/
int pixel_p{0};
int run{0};
for(uint32_t decoded_pixel{0}; decoded_pixel < num_pixels; decoded_pixel++)
{
if(run > 0)
{
run--;
}
else if(input.pointer() < chunks_len)
{
int b1 = input.read_ui8();
if (b1 == OP_RGB)
{
pixel.colors.red = input.read_ui8();
pixel.colors.green = input.read_ui8();
pixel.colors.blue = input.read_ui8();
}
else if (b1 == OP_RGBA)
{
pixel.colors.red = input.read_ui8();
pixel.colors.green = input.read_ui8();
pixel.colors.blue = input.read_ui8();
pixel.colors.alpha = input.read_ui8();
}
else if ((b1 & MASK_2_BITS) == OP_INDEX)
{
pixel = index[b1];
}
else if ((b1 & MASK_2_BITS) == OP_DIFF)
{
pixel.colors.red += ((b1 >> 4) & 0x03) - 2;
pixel.colors.green += ((b1 >> 2) & 0x03) - 2;
pixel.colors.blue += (b1 & 0x03) - 2;
}
else if ((b1 & MASK_2_BITS) == OP_LUMA)
{
int b2 = input.read_ui8();
int vg = (b1 & 0x3f) - 32;
pixel.colors.red += vg - 8 + ((b2 >> 4) & 0x0f);
pixel.colors.green += vg;
pixel.colors.blue += vg - 8 + (b2 & 0x0f);
}
else if ((b1 & MASK_2_BITS) == OP_RUN)
{
run = (b1 & 0x3f);
}
index[color_hash(pixel.colors) % 64] = pixel;
}
this->pixels[pixel_p++] = pixel.colors.red;
this->pixels[pixel_p++] = pixel.colors.green;
this->pixels[pixel_p++] = pixel.colors.blue;
if(this->channels == 4) this->pixels[pixel_p++] = pixel.colors.alpha;
}
}
Image::~Image()
{
delete[] this->pixels;
}
}
|
