vc读写BMP文件代码

void LoadDIBFile(LPSTR lpFilePath,unsigned char *pDIB)
{    
    BITMAPFILEHEADER bmfHeader;
    BITMAPINFOHEADER bmfInfo;
    
    //open the dib file
    HANDLE    hFile = CreateFile(lpFilePath,GENERIC_READ,NULL,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,NULL);
    if(hFile == INVALID_HANDLE_VALUE)
    {
        return;
    }
    
    DWORD dwSizeRead;
    if(!ReadFile(hFile,(LPBITMAPFILEHEADER)&bmfHeader,sizeof(bmfHeader),&dwSizeRead,NULL))
    {
        ::CloseHandle(hFile);
        return;
    }

    if(!ReadFile(hFile,(LPBITMAPFILEHEADER)&bmfInfo,sizeof(bmfInfo),&dwSizeRead,NULL))
    {
        ::CloseHandle(hFile);
        return;
    }    

    int nSize = GetFileSize(hFile,NULL) - sizeof(BITMAPFILEHEADER) - sizeof(BITMAPINFOHEADER);
    
    //check the file is DIB
    DWORD    dwFileType = ((DWORD)('M'<<8)|'B');
    if(bmfHeader.bfType != dwFileType)
    {
        ::CloseHandle(hFile);
        return;
    }
    
    // Read all lines (from bottom up)
    int    LineSize=bmfInfo.biWidth*bmfInfo.biBitCount/8;
    int Offs=LineSize*(bmfInfo.biHeight-1);
    for(int i=0;i<(UINT32)bmfInfo.biHeight;i++)
    {
        ReadFile(hFile,pDIB+Offs,LineSize,&dwSizeRead,NULL);
        Offs-=LineSize;
    }
    
    ::CloseHandle(hFile);
}

BOOL WriteBitmap(char *pFilename, UINT8 *pImage, BITMAPINFO *pInfo)
{
    OFSTRUCT    Ofs;
    HFILE       hFile;
    DWORD       i,LineSize,Offs;
    BITMAPFILEHEADER fh;
    BITMAPINFOHEADER bmi;
    
    if(!pInfo||!pImage)
        return FALSE;
    
    hFile=OpenFile(pFilename,&Ofs,OF_Create);
    if(hFile==HFILE_ERROR)
        return FALSE;
    
    // Copy Bitmapinfoheader (set Width and Height absolute)
    bmi=pInfo->bmiHeader;
    bmi.biWidth=abs(pInfo->bmiHeader.biWidth);
    bmi.biHeight=abs(pInfo->bmiHeader.biHeight);
    
#define BMTYPE          0x4d42
    // Build fileheader and write
    fh.bfType=BMTYPE;
    if(pInfo->bmiHeader.biBitCount==8)
    {
        fh.bfOffBits=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER)+
            256*sizeof(RGBQUAD);
        fh.bfSize=fh.bfOffBits+pInfo->bmiHeader.biSizeImage;
        bmi.biClrUsed=256;
        bmi.biClrImportant=0;
    }
    else
    {
        fh.bfOffBits=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER);
        fh.bfSize   =fh.bfOffBits+pInfo->bmiHeader.biSizeImage;
        bmi.biClrUsed=0;
        bmi.biClrImportant=0;
    }
    
    fh.bfReserved1=0;
    fh.bfReserved2=0;
    
    // Write fileheader
    _hwrite(hFile,(char*)&fh,sizeof(BITMAPFILEHEADER));
    
    // Write bitmapinfoheader
    _hwrite(hFile,(char*)&bmi,sizeof(BITMAPINFOHEADER));
    
    // Write Palette (only if grayscale)
    if(bmi.biClrUsed!=0)
        _hwrite(hFile,(char*)pInfo->bmiColors,pInfo->bmiHeader.biClrUsed*sizeof(RGBQUAD));
    
    // Write all lines (from bottom up)
    LineSize=bmi.biWidth*bmi.biBitCount/8;
    Offs=LineSize*(bmi.biHeight-1);
    for(i=0;i<(UINT32)bmi.biHeight;i++)
    {
        _hwrite(hFile,(char*)&pImage[Offs],LineSize);
        Offs-=LineSize;
    }
    
    _lclose(hFile);
    
    return TRUE;
}