BMP格式圖像讀取與存儲，bmp格式圖像

BMP格式圖像讀取與存儲，bmp格式圖像

全局變量:
 1 #include "stdafx.h"
 2 #include <windows.h>
 3 
 4 /*BMP位圖數據是4字節對齊*/
 5 #define WIDTHBYTES(bits) ((DWORD)(((bits)+31) & (~31)) / 8)
 6 #define WIDTHBYTES(bits) ((DWORD)((((bits)+31) / 32) * 4)
 7 
 8 unsigned char *gPBmpBuf ;     //指向圖像數據的指針
 9 int            gBmpWidth ;    //圖像的寬  
10 int            gBmpHeight;     //圖像的高
11 RGBQUAD       *gPColorTable ; //顏色表指針
12 int            gBiBitCount;   //圖像類型，每個像素的位數
13 char           bmp[100] = "E:/test_pic.bmp";
14 char           saveBmp[100] = "E:/save_pic.bmp";

讀取bmp文件：

 1 bool loadBmp(char *bmpName)
 2 {
 3     /*以二進制方式打開bmp文件*/
 4     FILE *fp = fopen(bmpName , "rb");
 5     if(NULL == fp)
 6     {
 7         printf("open file \"%s\" failed \n" , bmpName);
 8         return false ;
 9     }
10 
11     /*跳過bmp文件結構體*/
12     fseek(fp , sizeof(BITMAPFILEHEADER),0);
13 
14     /*讀取bmp文件信息頭*/
15     BITMAPINFOHEADER infoHead ; 
16     fread(&infoHead , sizeof(BITMAPINFOHEADER),1 , fp);
17 
18     /*獲取圖像寬，高，像素位數*/
19     gBmpWidth  = infoHead.biWidth ; 
20     gBmpHeight = infoHead.biHeight;
21     gBiBitCount= infoHead.biBitCount;
22 
23     /*獲取每行像素所占內存大小(必須為4的倍數)*/
24     int lineByte = (gBmpWidth*gBiBitCount/8 + 3)/4*4 ;
25 
26     /*灰度圖像有顏色表，且顏色表表項為256,24-位真彩色圖像就不使用彩色板*/
27     if(8 == gBiBitCount)
28     {
29         gPColorTable = (RGBQUAD *)malloc(sizeof(RGBQUAD)*256);
30         fread(gPColorTable , sizeof(RGBQUAD) , 1  , fp);
31     }
32 
33     /*申請位圖數據空間，並將位圖數據存放到內存*/
34     gPBmpBuf = (unsigned char *)malloc(sizeof(unsigned char)*gBmpHeight*lineByte);
35     fread(gPBmpBuf,1 ,gBmpHeight*lineByte,fp);
36 
37     fclose(fp);
38 
39     return true ;
40 }

保存bmp文件格式：

 1 bool storeBmp(char *bmpName , unsigned char *imgBuf , int width , int height,
 2               int gBiBitCount , RGBQUAD *gPColorTable )
 3 {
 4     /*對位圖數據進行判空操作*/
 5     if(NULL == imgBuf)
 6     {
 7         return false ;
 8     }
 9 
10     /*根據像素位數，判斷當前顏色表大小*/
11     int colorTableSize = 0 ;
12     if(gBiBitCount == 8)
13     {
14         /*
15            1字節用於藍色分量
16            1字節用於綠色分量
17            1字節用於紅色分量
18            1字節用於填充符(設置為0)
19          */
20         colorTableSize = 1024 ; /*4*256*/
21     }
22 
23     /*待存儲圖像數據每行像素的大小(4的倍數)*/
24     int lineByte = (gBmpWidth*gBiBitCount/8 + 3)/4*4 ;
25 
26     FILE *fp = fopen(bmpName , "wb");
27     if(NULL == fp)
28     {
29         printf("creat file failed !\n");
30         return false ;
31     }
32 
33     /*填寫位圖文件頭結構體*/
34     BITMAPFILEHEADER fileHead ; 
35     fileHead.bfType = 0x4D42 ; //bmp類型
36     fileHead.bfSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) +
37                       colorTableSize + lineByte*height ; 
38     fileHead.bfReserved1 = 0 ;
39     fileHead.bfReserved2 = 0 ;
40     fileHead.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) +
41                          colorTableSize ;
42     fwrite(&fileHead , sizeof(BITMAPFILEHEADER),1 , fp);
43 
44     /*填寫位圖信息結構體*/
45     BITMAPINFOHEADER infoHead ;
46     infoHead.biBitCount = gBiBitCount ; 
47     infoHead.biClrImportant = 0 ;
48     infoHead.biClrUsed = 0 ;
49     infoHead.biCompression = 0 ;
50     infoHead.biHeight = height ;
51     infoHead.biPlanes = 1 ;
52     infoHead.biSize = 40 ;
53     infoHead.biSizeImage = lineByte*height ;
54     infoHead.biWidth = width ;
55     infoHead.biXPelsPerMeter = 0 ;
56     infoHead.biYPelsPerMeter = 0 ;
57     fwrite(&infoHead , sizeof(BITMAPINFOHEADER),1 , fp);
58 
59     /*填寫顏色表*/
60     if(gBiBitCount == 8)
61     {
62         fwrite(&gPColorTable , sizeof(RGBQUAD),256 , fp);
63     }
64 
65      /*寫位圖數據進文件*/
66     fwrite( imgBuf, height * lineByte, 1, fp );
67 
68     fclose(fp);
69 
70     return true ; 
71 }

main入口測試:

 1 int _tmain(int argc, _TCHAR* argv[])
 2 {
 3     
 4     bool ret = false ;
 5 
 6     ret |= loadBmp(bmp);
 7     ret |= storeBmp(saveBmp,gPBmpBuf,gBmpWidth,gBmpHeight,gBiBitCount,gPColorTable);
 8 
 9     if(false == ret)
10     {
11         printf("excut fail! \n");
12     }
13     else if(true == ret)
14     {
15         printf("excut success!\n");
16     }
17     
18     if(gBiBitCount == 8)
19     {
20         free(gPColorTable);
21     }
22 
23     free(gPBmpBuf);
24     
25     return 0;
26 }