纯C下的读写BMP文件代码

纯C代码下读写BMP文件代码，简单易懂。

/**//*************************************************************
**Copyright(c)2007,Shanghai
**
**文件名称：read_write_bmp_with_C.c
**编译:VisualC++/ANSIC/ISOC++
**日期：2007.10.24
**************************************************************/

#include"stdio.h"
#include"stdlib.h"

#definePIXPLINE320

typedefstructtagRGBQUAD...{//定义每个像素的数据类型
unsignedcharrgbBlue;
unsignedcharrgbGreen;
unsignedcharrgbRed;
}RGBQUAD;

intbmp_read(unsignedchar*image,intxsize,intysize,char*filename)...{
charfname_bmp[128];
sprintf(fname_bmp,"%s.bmp",filename);

FILE*fp;
if(!(fp=fopen(fname_bmp,"rb")))
return-1;

unsignedcharheader[54];
fread(header,sizeof(unsignedchar),54,fp);
fread(image,sizeof(unsignedchar),(size_t)(long)xsize*ysize*3,fp);

fclose(fp);
return0;
}

intbmp_write(unsignedchar*image,intxsize,intysize,char*filename)...{
unsignedcharheader[54]=...{
0x42,0x4d,0,0,0,0,0,0,0,0,
54,0,0,0,40,0,0,0,0,0,0,0,0,0,0,0,1,0,24,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0
};

longfile_size=(long)xsize*(long)ysize*3+54;
header[2]=(unsignedchar)(file_size&0x000000ff);
header[3]=(file_size>>8)&0x000000ff;
header[4]=(file_size>>16)&0x000000ff;
header[5]=(file_size>>24)&0x000000ff;

longwidth=xsize;
header[18]=width&0x000000ff;
header[19]=(width>>8)&0x000000ff;
header[20]=(width>>16)&0x000000ff;
header[21]=(width>>24)&0x000000ff;

longheight=ysize;
header[22]=height&0x000000ff;
header[23]=(height>>8)&0x000000ff;
header[24]=(height>>16)&0x000000ff;
header[25]=(height>>24)&0x000000ff;

charfname_bmp[128];
sprintf(fname_bmp,"%s.bmp",filename);

FILE*fp;
if(!(fp=fopen(fname_bmp,"wb")))
return-1;

fwrite(header,sizeof(unsignedchar),54,fp);
fwrite(image,sizeof(unsignedchar),(size_t)(long)xsize*ysize*3,fp);

fclose(fp);
return0;
}

voidclonebmp(unsignedchar*image,intxsize,intysize)
...{
bmp_read(image,xsize,ysize,"orgbmp");//orgbmp为当前目录下的bmp文件名
bmp_write(image,xsize,ysize,"clone_bmp");//clone_bmp为克隆的bmp文件名
}


/**//****************************************************************************
*名称：youwritetobmp()
*功能：写入bmp文件
*入口参数：RGBQUAD*pixarr----要写入的像素数组指针,intxsize----图像宽度,intysize----图像高度,char*filename--图像名称
*出口参数：无
*返回值：-1:错误；0：正确
****************************************************************************/
intyouwritetobmp(RGBQUAD*pixarr,intxsize,intysize,char*filename)...{
unsignedcharheader[54]=...{
0x42,0x4d,0,0,0,0,0,0,0,0,
54,0,0,0,40,0,0,0,0,0,
0,0,0,0,0,0,1,0,24,0,
0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,
0,0,0,0
};
inti;
intj;
longfile_size=(long)xsize*(long)ysize*3+54;
header[2]=(unsignedchar)(file_size&0x000000ff);
header[3]=(file_size>>8)&0x000000ff;
header[4]=(file_size>>16)&0x000000ff;
header[5]=(file_size>>24)&0x000000ff;

longwidth;
if(!(xsize%4))width=xsize;
elsewidth=xsize+(4-xsize%4);//如不是4的倍数，则转换成4的倍数
header[18]=width&0x000000ff;
header[19]=(width>>8)&0x000000ff;
header[20]=(width>>16)&0x000000ff;
header[21]=(width>>24)&0x000000ff;

longheight=ysize;
header[22]=height&0x000000ff;
header[23]=(height>>8)&0x000000ff;
header[24]=(height>>16)&0x000000ff;
header[25]=(height>>24)&0x000000ff;

charfname_bmp[128];
sprintf(fname_bmp,"%s.bmp",filename);

FILE*fp;
if(!(fp=fopen(fname_bmp,"wb")))
return-1;

fwrite(header,sizeof(unsignedchar),54,fp);

RGBQUADzero=...{0,0,0};//不足字节，用zero填充

for(j=0;j<ysize;j++)...{
if(!(xsize%4))...{
for(i=0;i<xsize;i++)...{
fwrite(pixarr+i,sizeof(RGBQUAD),1,fp);
}
}
else
...{
for(i=0;i<xsize;i++)...{
fwrite(pixarr+i,sizeof(RGBQUAD),1,fp);
}
for(i=xsize;i<xsize+(4-xsize%4);i++)...{
fwrite(&zero,sizeof(RGBQUAD),1,fp);
}
}
}

fclose(fp);
return0;

}

intmain()...{
unsignedchar*image;
intxsize=320;
intysize=163;

RGBQUADpixarray[PIXPLINE];//一行像素值数组

image=(unsignedchar*)malloc((size_t)xsize*ysize*3);
if(image==NULL)
return-1;
clonebmp(image,xsize,ysize);//功能一：实现一副图像的拷贝


youwritetobmp(pixarray,xsize,ysize,"yourimage");