1 /*************************************************
2 Author:
3 Date:2013-01-23
4 **************************************************/
5 #include
"stdafx.h"
6 //Visual studio 2010版中应该放到stdafx.h文件中的头文件们
7 #include<math.h>
8 #include <iomanip>
9 #include <stdlib.h>
10 #include <windows.h>
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <iostream>
14 #include <fstream>
15 //
16 using namespace System;
17 using namespace std;
18 /*************************************************
19
20 Function: bitmapToGray
21
22 Description: 将BMP格式的灰度图像或24位真彩图像二值化，并生成新图像
23
24 Input: srcBMP - 待处理的图像路径
25
26 Output: grayBMP - 处理后生成的新图像
27
28 Return: 0 - 处理失败
29 1 - 处理成功
30
31 *************************************************/
32
33 int bitmapToGray(
char *srcBMP,
char *
grayBMP)
34 {
35 unsigned
char *Bmp24Buf,*
Bmp8Buf;
36 int height,width,bitCount;
37 BITMAPFILEHEADER bmpFileHeader;
38 BITMAPINFOHEADER bmpInfoHeader;
39 FILE *rfp,*
wfp;
40 RGBQUAD *
pColorTable;
41 //读取原文件
42 rfp=fopen(srcBMP,
"rb");
43 if(rfp==
NULL)
44 {
45 printf(
"文件不存在！\n");
46 return 0;
47 }
48 //读取文件头
49 fread(&bmpFileHeader,
sizeof(BITMAPFILEHEADER),
1,rfp);
50 //读取文件信息
51 fread(&bmpInfoHeader,
sizeof(BITMAPINFOHEADER),
1,rfp);
52 width =
bmpInfoHeader.biWidth;
53 height =
bmpInfoHeader.biHeight;
54 bitCount =
bmpInfoHeader.biBitCount;
55
56 //定义变量，计算图像每行像素所占的字节数（必须是4的倍数）
57 int lineByte=(width * bitCount/
8+
3)/
4*
4;
58 //灰度图像有颜色表，且颜色表表项为256
59 pColorTable=
new RGBQUAD[
256];
60 if(bitCount==
8)
61 {
62 //申请颜色表所需要的空间，读颜色表进内存
63 fread(pColorTable,
sizeof(RGBQUAD),
256,rfp);
64 Bmp8Buf=
new unsigned
char[lineByte *
height];
65 fread(Bmp8Buf,
1,lineByte *
height,rfp);
66 //二值化
67 for(
int i=
0;i<height;i++
)
68 {
69 for(
int j=
0;j<lineByte;j++
)
70 {
71 if(Bmp8Buf[i*lineByte+j]>
128)
72 Bmp8Buf[i*lineByte+j]=
255;
73 else Bmp8Buf[i*lineByte+j]=
0;
74 }
75 }
76 //关闭文件
77 fclose(rfp);
78 //写文件
79 wfp=fopen(grayBMP,
"wb");
80 if(wfp==
NULL)
81 {
82 printf(
"open savefile error\n");
83 return 0;
84 }
85 fwrite(&bmpFileHeader,
sizeof(BITMAPFILEHEADER),
1,wfp);
86 fwrite(&bmpInfoHeader,
sizeof(BITMAPINFOHEADER),
1,wfp);
87 fwrite(pColorTable,
sizeof(RGBQUAD),
256,wfp);
88 fwrite(Bmp8Buf,
sizeof(unsigned
char),lineByte *
height,wfp);
89 fclose(wfp);
90 }
91 else if(bitCount==
24)
92 {
93 int lineByte24to8=(width+
3)/
4*
4;
//灰度图实际每行像素数
94 //文件信息头
95 bmpInfoHeader.biBitCount =
8;
96 bmpInfoHeader.biSizeImage = lineByte24to8 *
height;
97 //文件头
98 bmpFileHeader.bfOffBits =
sizeof(BITMAPFILEHEADER)+
sizeof(BITMAPINFOHEADER)+
256*
sizeof(RGBQUAD);
99 bmpFileHeader.bfSize = bmpFileHeader.bfOffBits +
bmpInfoHeader.biSizeImage;
100 //颜色表
101 for(
int i=
0;i<
256;i++
)
102 {
103 pColorTable[i].rgbBlue=
i;
104 pColorTable[i].rgbGreen=
i;
105 pColorTable[i].rgbRed=
i;
106 pColorTable[i].rgbReserved=
0;
107 }
108 //二值化
109 Bmp24Buf=
new unsigned
char[lineByte *
height];
110 Bmp8Buf=
new unsigned
char[lineByte24to8 *
height];
111 fread(Bmp24Buf,
1,lineByte *
height,rfp);
112 for(
int i=
0;i<height;i++
)
113 {
114 for(
int j=
0;j<lineByte24to8;j++
)
115 {
116 Bmp8Buf[i*lineByte24to8+j]=Bmp24Buf[i*lineByte+j*
3]*
0.299+Bmp24Buf[i*lineByte+j*
3+
1]*
0.587+Bmp24Buf[i*lineByte+j*
3+
2]*
0.114;
117 if(Bmp8Buf[i*lineByte24to8+j]>
128)
118 Bmp8Buf[i*lineByte24to8+j]=
255;
119 else Bmp8Buf[i*lineByte24to8+j]=
0;
120 }
121 }
122
123 //关闭文件
124 fclose(rfp);
125 //写文件
126 wfp=fopen(grayBMP,
"wb");
127 if(wfp==
NULL)
128 {
129 printf(
"open savefile error\n");
130 return 0;
131 }
132 fwrite(&bmpFileHeader,
sizeof(BITMAPFILEHEADER),
1,wfp);
133 fwrite(&bmpInfoHeader,
sizeof(BITMAPINFOHEADER),
1,wfp);
134 fwrite(pColorTable,
sizeof(RGBQUAD),
256,wfp);
135 fwrite(Bmp8Buf,
1,lineByte24to8 *
height,wfp);
136 fclose(wfp);
137 }
138 if(Bmp8Buf!=
NULL)
139 {
140 delete Bmp8Buf;
141 }
142 if(Bmp24Buf!=
NULL)
143 {
144 delete Bmp24Buf;
145 }
146 return 1;
147 }
148
149 void main( )
150 {
151 bitmapToGray(
"songbie.bmp",
"gg.bmp");
152 }
转载于:https://www.cnblogs.com/QuentinYo/archive/2013/01/23/2873762.html
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