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
|
/* See LICENSE file for copyright and license details. */
#include <arpa/inet.h>
#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <jpeglib.h>
static char *argv0;
METHODDEF(void)
jpeg_error(j_common_ptr cinfo)
{
fprintf(stderr, "%s: libjpeg: ", argv0);
(*cinfo->err->output_message)(cinfo);
exit(1);
}
int
main(int argc, char *argv[])
{
struct jpeg_decompress_struct cinfo;
struct jpeg_error_mgr jerr;
uint32_t width, height, val_be;
uint16_t *ff_row;
size_t jpeg_row_len, ff_row_len, i, dx, sx;
JSAMPARRAY buffer; /* output row buffer */
argv0 = argv[0], argc--, argv++;
if (argc > 1) {
fprintf(stderr, "usage: %s\n", argv0);
return 1;
}
/* load jpg */
cinfo.err = jpeg_std_error(&jerr);
jerr.error_exit = jpeg_error;
jpeg_create_decompress(&cinfo);
jpeg_stdio_src(&cinfo, stdin);
jpeg_read_header(&cinfo, TRUE);
width = cinfo.image_width;
height = cinfo.image_height;
/* set output format */
cinfo.output_components = 3; /* color components per pixel */
cinfo.out_color_space = JCS_RGB; /* input color space */
jpeg_start_decompress(&cinfo);
jpeg_row_len = width * cinfo.output_components;
/* create output buffers */
buffer = (*cinfo.mem->alloc_sarray)((j_common_ptr)&cinfo,
JPOOL_IMAGE, jpeg_row_len, 1);
ff_row_len = strlen("RGBA") * width;
if(!(ff_row = malloc(ff_row_len * sizeof(uint16_t)))) {
fprintf(stderr, "%s: malloc: out of memory\n", argv0);
return 1;
}
/* write header */
fprintf(stdout, "farbfeld");
val_be = htonl(width);
if (fwrite(&val_be, sizeof(uint32_t), 1, stdout) != 1)
goto writerr;
val_be = htonl(height);
if (fwrite(&val_be, sizeof(uint32_t), 1, stdout) != 1)
goto writerr;
while (cinfo.output_scanline < cinfo.output_height) {
/* jpeg_read_scanlines expects an array of pointers to scanlines.
* Here the array is only one element long, but you could ask for
* more than one scanline at a time if that's more convenient. */
jpeg_read_scanlines(&cinfo, buffer, 1);
for (i = 0, dx = 0, sx = 0; i < width; i++, sx += 3, dx += 4) {
ff_row[dx] = htons(buffer[0][sx] * 257);
ff_row[dx+1] = htons(buffer[0][sx+1] * 257);
ff_row[dx+2] = htons(buffer[0][sx+2] * 257);
ff_row[dx+3] = htons(65535);
}
/* write data */
if (fwrite(ff_row, 2, ff_row_len, stdout) != ff_row_len)
goto writerr;
}
jpeg_finish_decompress(&cinfo);
jpeg_destroy_decompress(&cinfo);
return 0;
writerr:
fprintf(stderr, "%s: fwrite: ", argv0);
perror(NULL);
return 1;
}
|
