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
| #include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <setjmp.h>
#include <math.h>
#include <sys/time.h>
#include <time.h>
// jpeg库头文件必须放到stdio.h后面
#include "libjpeg/include/jpeglib.h"
#include "libjpeg/include/jerror.h"
typedef struct my_error_mgr * my_error_ptr;
void my_error_exit (j_common_ptr cinfo)
{
my_error_ptr myerr = (my_error_ptr) cinfo->err;
(*cinfo->err->output_message) (cinfo);
longjmp(myerr->setjmp_buffer, 1);
}
int jpeg2rgb(unsigned char* jpeg_buffer, int jpeg_size, unsigned char* rgb_buffer, int* size, int* width, int* height)
{
struct jpeg_decompress_struct cinfo;
struct my_error_mgr jerr;
JSAMPARRAY buffer;
int row_stride = 0;
unsigned char* tmp_buffer = NULL;
int rgb_size;
if (jpeg_buffer == NULL)
{
printf("no jpeg buffer here.\n");
return -1;
}
if (rgb_buffer == NULL)
{
printf("you need to alloc rgb buffer.\n");
return -1;
}
cinfo.err = jpeg_std_error(&jerr.pub);
jerr.pub.error_exit = my_error_exit;
if (setjmp(jerr.setjmp_buffer))
{
jpeg_destroy_decompress(&cinfo);
return -1;
}
jpeg_create_decompress(&cinfo);
jpeg_mem_src(&cinfo, jpeg_buffer, jpeg_size);
jpeg_read_header(&cinfo, TRUE);
//cinfo.out_color_space = JCS_RGB; //JCS_YCbCr; // 设置输出格式
jpeg_start_decompress(&cinfo);
row_stride = cinfo.output_width * cinfo.output_components;
*width = cinfo.output_width;
*height = cinfo.output_height;
rgb_size = row_stride * cinfo.output_height; // 总大小
if (*size < rgb_size)
{
printf("rgb buffer to small, we need %d but has only: %d\n", rgb_size, *size);
}
*size = rgb_size;
buffer = (*cinfo.mem->alloc_sarray)((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);
printf("debug--:\nrgb_size: %d, size: %d w: %d h: %d row_stride: %d \n", rgb_size,
cinfo.image_width*cinfo.image_height*3,
cinfo.image_width,
cinfo.image_height,
row_stride);
tmp_buffer = rgb_buffer;
while (cinfo.output_scanline < cinfo.output_height) // 解压每一行
{
jpeg_read_scanlines(&cinfo, buffer, 1);
// 复制到内存
memcpy(tmp_buffer, buffer[0], row_stride);
tmp_buffer += row_stride;
}
jpeg_finish_decompress(&cinfo);
jpeg_destroy_decompress(&cinfo);
return 0;
}
int rgb2jpeg(unsigned char* rgb_buffer, int width, int height, int quality, unsigned char** jpeg_buffer, unsigned long* jpeg_size)
{
struct jpeg_compress_struct cinfo;
struct jpeg_error_mgr jerr;
int row_stride = 0;
JSAMPROW row_pointer[1];
if (jpeg_buffer == NULL)
{
printf("you need a pointer for jpeg buffer.\n");
return -1;
}
cinfo.err = jpeg_std_error(&jerr);
jpeg_create_compress(&cinfo);
jpeg_mem_dest(&cinfo, jpeg_buffer, jpeg_size);
cinfo.image_width = width;
cinfo.image_height = height;
cinfo.input_components = 3;
cinfo.in_color_space = JCS_RGB;
jpeg_set_defaults(&cinfo);
jpeg_set_quality(&cinfo, quality, 1); // todo 1 == true
jpeg_start_compress(&cinfo, TRUE);
row_stride = width * cinfo.input_components;
while (cinfo.next_scanline < cinfo.image_height)
{
row_pointer[0] = &rgb_buffer[cinfo.next_scanline * row_stride];
jpeg_write_scanlines(&cinfo, row_pointer, 1);
}
jpeg_finish_compress(&cinfo);
jpeg_destroy_compress(&cinfo);
return 0;
}
|
