[HELP]诚心请热心人帮忙,先谢了,看看哪里不行!
此程序是BMP文件头文件的读取,编译无错,但读取信息不对口!
图片地址在此:http://p.blog.csdn.net/images/p_blog_csdn_net/jianxiong8814/291722/o_TEST24.BMP
#include "stdio.h "
typedef char CHAR;
typedef short SHORT;
typedef long LONG;
typedef unsigned long DWORD;//4个字节
typedef int BOOL; //4个字节
typedef unsigned char BYTE; //1个字节
typedef unsigned short WORD; //2个字节
WORD Width,Height,BitCount,Planes,ImageType;
WORD Compression,Orientation;
DWORD OffBits,ColorMap,Size;
WORD BytesPerLine,ColorNum;
//文件头结构体的定义，14字节
typedef struct tagBITMAPFILEHEADER {
WORD bfType;//2字节
DWORD bfSize;//4
WORD bfReserved1;//2
WORD bfReserved2;//2
DWORD bfOffBits;//4
} BITMAPFILEHEADER;
//位图信息头的定义，40字节
typedef struct tagBITMAPINFOHEADER{
DWORD biSize;//4
LONG biWidth;//4
LONG biHeight;//4
WORD biPlanes;//2
WORD biBitCount;//2
DWORD biCompression; //4
DWORD biSizeImage;//4
LONG biXPelsPerMeter; //4
LONG biYPelsPerMeter;//4
DWORD biClrUsed;//4
DWORD biClrImportant;//4
} BITMAPINFOHEADER;
//读BMP文件头函数
int loadBMPhead(char *file) /* 读BMP文件头 */
{
BITMAPFILEHEADER bmphead;
BITMAPINFOHEADER bmi;
FILE *fp;
int flag=0;
fp=fopen(file, "rb ");/* 打开图像文件 */
if (fp != NULL) {
flag=1;
fseek(fp,0L,SEEK_SET);
fread(&bmphead,sizeof(BITMAPFILEHEADER),1,fp);/* 读位图文件头 */
fread(&bmi,sizeof(BITMAPINFOHEADER),1,fp); /* 读位图信息头 */
/* 以下取出图像参数 */
OffBits = bmphead.bfOffBits;
Width = (WORD) bmi.biWidth;
Height = (WORD) bmi.biHeight;
BitCount = bmi.biBitCount;
Planes = bmi.biPlanes;
Compression = (WORD) bmi.biCompression;
BytesPerLine = (Width*BitCount+31)/32*4; /* 计算每行字节数 */
ColorMap = sizeof(BITMAPFILEHEADER) + bmi.biSize;
ColorNum = 0;
fclose(fp); /* 关闭图像文件 */
}
return(flag);
}
main()
{
loadBMPhead( "C://TEST24.bmp ");
exit(1);
}
//图片地址在此:http://p.blog.csdn.net/images/p_blog_csdn_net/jianxiong8814/291722/o_TEST24.BMP
大家注意:下面是结构体里个各量的正确值，不知道为什么我老是得不到文件头和信息头的正确值
typedef struct tagBITMAPFILEHEADER {
WORD bfType;// 'BM '或0X424D或16973
DWORD bfSize;//137144
WORD bfReserved1;//0
WORD bfReserved2;//0
DWORD bfOffBits;//54
} BITMAPFILEHEADER;
typedef struct tagBITMAPINFOHEADER{
DWORD biSize;//40
LONG biWidth;//181
LONG biHeight;//252
WORD biPlanes;//1
WORD biBitCount;//24
DWORD biCompression;//0
DWORD biSizeImage;//0
LONG biXPelsPerMeter;//2834
LONG biYPelsPerMeter;//2834
DWORD biClrUsed;//0
DWORD biClrImportant;//0
} BITMAPINFOHEADER;
//大家也可以用自己的图片调试，其实也不难知道对不对
请大家帮帮忙指出错误，谢谢了！
我确实不知道哪里错了，哎。。。。
[解决办法]
lz在编译时，结构体的对齐有没有设置成按1字节对齐？
[解决办法]
同意WizardLucien~~
在结构体前后分别加上
#pragma pack(push,1)
#pragma pack(pop)
或者只加
#pragma pack(1)
即可
[解决办法]
估计就这个问题吧
[解决办法]
http://www.5inet.net/Develop/Visual%20C/029645,ZaiVCZhongZiJianCaoZuoBMPLiTuWenJianDeLei.aspx
[解决办法]
恩， 应该是结构体对齐的问题 ～～
对齐单位不正确，
导致 sizeof 不正确，
读取的信息就出错了～
[解决办法]
结构体对齐
[解决办法]
一定要加吗？？我也在写BMP图像的读取，没有加楼上说的那个对齐也可以正确显示哦！
#include <stdlib.h>
#include <stdio.h>
#include <malloc.h>
#include <math.h>
typedef unsigned short int WORD;
typedef unsigned long int DWORD;
typedef unsigned char BYTE ;
typedef struct tagBITMAPFILEHEADER {
WORD bfType;
DWORD bfSize;
WORD bfReserved1;
WORD bfReserved2;
DWORD bfOffBits;
} BITMAPFILEHEADER;
typedef struct tagBITMAPINFOHEADER {
DWORD biSize;
DWORD biWidth;
DWORD biHeight;
WORD biPlanes;
WORD biBitCount;
DWORD biCompression;
DWORD biSizeImage;
DWORD biXPelsPerMeter;
DWORD biYPelsPerMeter;
DWORD biClrUsed;
DWORD biClrImportant;
} BITMAPINFOHEADER;
typedef struct tagRGBQUAD {
BYTE rgbBlue;
BYTE rgbGreen;
BYTE rgbRed;
BYTE rgbReserved;
} RGBQUAD;
BITMAPFILEHEADER bmfHeader; /*BMP file header*/
BITMAPINFOHEADER bmiHeader; /*BMP info header*/
void main(void)
{
FILE *fp;
int Palette_Num;
int Width,Height, Width_4;
int i, j;
if ((fp=fopen( "d:\\1.bmp ", "rb "))==NULL){
printf( "can not open source file\n ");
exit(0);
}
fread(&bmfHeader,sizeof(bmfHeader),1,fp);
fread(&bmiHeader,sizeof(bmiHeader),1,fp);
printf( "Print File Header:\n ");
printf( "bfType=%x \n ",bmfHeader.bfType);
printf( "bfSize=%d \n ",bmfHeader.bfSize);
printf( "bfOffBits=%d \n ",bmfHeader.bfOffBits);
printf( "\n Printf Information Header:\n ");
printf( "biSize=%d \n ",bmiHeader.biSize);
printf( "biWidth=%d \n ",bmiHeader.biWidth);
printf( "biHeight=%d \n ",bmiHeader.biHeight);
printf( "biBitCount=%d \n ",bmiHeader.biBitCount);
printf( "biClrUsed=%d \n ",bmiHeader.biClrUsed);
getchar();
}
