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
|
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <getopt.h>
#include "args.h"
#include "ppm.h"
static Image image_convolution(Image input, float kernel[9]);
static void split_rgb(Image input, uint8_t *r, uint8_t *g, uint8_t *b);
static void merge_rgb(Image *out, uint8_t *r, uint8_t *g, uint8_t *b);
static uint8_t kernel_op(uint8_t *data, float kernel[9], int i, int j, int w, int h);
static void usage(void);
void
usage(void)
{
fprintf(stderr, "Usage: dsco [INPUT] -f [edge|blur] [-o OUTPUT]\n");
exit(1);
}
Image
image_convolution(Image input, float kernel[9])
{
Image out;
out.width = input.width;
out.height = input.height;
out.pixel_bits = input.pixel_bits;
size_t n_pixels = out.width * out.height * 3;
out.data = calloc(n_pixels, sizeof(uint8_t));
if (out.data == NULL) {
perror("image_convolution() Error");
exit(1);
}
uint8_t *r, *g, *b;
uint8_t red, green, blue;
r = calloc(input.width * input.height, sizeof(uint8_t));
g = calloc(input.width * input.height, sizeof(uint8_t));
b = calloc(input.width * input.height, sizeof(uint8_t));
split_rgb(input, r, g, b);
int i, j, index;
for (i = 0; i < input.height; i++) {
for (j = 0; j < input.width; j++) {
index = i * input.width + j;
red = kernel_op(r, kernel, i, j, input.width, input.height);
green = kernel_op(g, kernel, i, j, input.width, input.height);
blue = kernel_op(b, kernel, i, j, input.width, input.height);
out.data[index * 3] = red;
out.data[index * 3 + 1] = green;
out.data[index * 3 + 2] = blue;
}
}
//merge_rgb(&out, r, g, b);
free(r);
free(g);
free(b);
return out;
}
void
merge_rgb(Image *out, uint8_t *r, uint8_t *g, uint8_t *b)
{
int i;
for (i = 0; i < out->width * out->height; i++) {
out->data[3 * i] = r[i];
out->data[3 * i + 1] = g[i];
out->data[3 * i + 2] = b[i];
}
}
uint8_t
kernel_op(uint8_t *data, float kernel[9], int i, int j, int w, int h)
{
float kernel_value = 0;
int ki, kj, img_index, index_i, index_j, index_k;
for (ki = 0; ki < 3; ki++) {
for (kj = 0; kj < 3; kj++) {
index_i = i + ki - 1; //height
index_j = j + kj - 1; //width
index_k = 3 * ki + kj;
if (index_i < 0
|| index_i >= h
|| index_j < 0
|| index_j >= w)
kernel_value += data[i * w + j] * kernel[index_k];
else {
img_index = index_i * w + index_j;
kernel_value += data[img_index] * kernel[index_k];
}
}
}
kernel_value = (kernel_value > 255) ? 255: kernel_value;
kernel_value = (kernel_value < 0) ? 0: kernel_value;
return (uint8_t)kernel_value;
}
void
split_rgb(Image input, uint8_t *r, uint8_t *g, uint8_t *b)
{
if (!r || !g || !b) {
perror("rgb_split() Error");
exit(1);
}
int i;
for (i = 0; i < input.width * input.height; i++) {
r[i] = input.data[3 * i];
g[i] = input.data[3 * i + 1];
b[i] = input.data[3 * i + 2];
}
}
int main(int argc, char *argv[])
{
int opt;
char *cli_arg;
char *filter, *out_file, *in_file;
cli_arg = in_file = filter = out_file = NULL;
while ((opt = args_getopt(argc, argv, "hf:o:", &cli_arg)) != -1) {
switch (opt) {
case 'f':
filter = cli_arg;
break;
case 'o':
out_file = cli_arg;
break;
case 0:
in_file = cli_arg;
break;
default:
usage();
}
}
char default_input[] = "/dev/stdin";
char default_output[] = "/dev/stdout";
if (!in_file) in_file = default_input;
if (!in_file) in_file = default_output;
float edge[9] = {
-1, -1, -1,
-1, 8, -1,
-1, -1, -1,
};
float blur[9] = {
1, 2, 1,
2, 4, 2,
1, 2, 1,
};
int i;
for (i = 0; i < 9; i++) blur[i] /= 16;
float sharpen[9] = {
0, -1, 0,
-1, 5, -1,
0, -1, 0,
};
float *kernel = NULL;
if (!strcmp(filter, "edge")) kernel = edge;
else if (!strcmp(filter, "blur")) kernel = blur;
else if (!strcmp(filter, "sharpen")) kernel = sharpen;
else usage();
Image img, out;
ppm_read(in_file, &img);
out = image_convolution(img, kernel);
ppm_write(out_file, &out);
return 0;
}
|
