求用VC平台读入BMP图像并保存的程序

Question

用VC平台读入BMP图像并保存的程序

Answer 1

使用CImage类，它可以读取并保存很多种图像格式

Answer 2

BOOL CFSBitmap::LoadBmpFile(LPCTSTR strFileName)
{
Free();

HFILE              hf;
    LPBITMAPINFOHEADER lpImgData;
    LOGPALETTE         *pPal;
    LPRGBQUAD          lpRGB;
    HPALETTE           hPrevPalette; 
    HDC                hDc;
HLOCAL             hPal;
DWORD         ImgSize;
DWORD              i;

    if((hf=_lopen(strFileName, OF_READ)) == HFILE_ERROR){
        MessageBox("BMP File  not found!","Error Message",MB_OK|MB_ICONEXCLAMATION);
        return FALSE;
}
m_strFileName = strFileName;
_lread(hf,(LPSTR)&bf,sizeof(BITMAPFILEHEADER)); 
_lread(hf,(LPSTR)&bi,sizeof(BITMAPINFOHEADER));
LineBytes=(DWORD)WIDTHBYTES(bi.biWidth*bi.biBitCount);
ImgSize=(DWORD)LineBytes*bi.biHeight;
    if(bi.biClrUsed!=0)
NumColors=(DWORD)bi.biClrUsed;
else
        switch(bi.biBitCount){
        case 1:
NumColors=2;
break;
case 4:
NumColors=16;
break;
case 8:
NumColors=256;
break;
case 24:
NumColors=0;
break;
default:
MessageBox("Invalid color numbers!","Error Message",MB_OK|MB_ICONEXCLAMATION);
_lclose(hf);
return FALSE; 
}
if(bf.bfOffBits!=(DWORD)(NumColors*sizeof(RGBQUAD)+sizeof(BITMAPFILEHEADER)
+sizeof(BITMAPINFOHEADER)))
{
MessageBox("Invalid color numbers!","Error Message" ,MB_OK|
MB_ICONEXCLAMATION);
_lclose(hf);
return FALSE; 
}
bf.bfSize=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER)+NumColors*sizeof(RGBQUAD)+ImgSize;
if((hImgData=GlobalAlloc(GHND,(DWORD)(sizeof(BITMAPINFOHEADER)+
NumColors*sizeof(RGBQUAD)+ImgSize)))==NULL)
{
MessageBox("Error alloc memory!","ErrorMessage",MB_OK|
MB_ICONEXCLAMATION);
_lclose(hf);
return FALSE;
}

lpImgData=(LPBITMAPINFOHEADER)GlobalLock(hImgData); 
    _llseek(hf,sizeof(BITMAPFILEHEADER),SEEK_SET);
_hread(hf,(char *)lpImgData,(long)sizeof(BITMAPINFOHEADER)
+(long)NumColors*sizeof(RGBQUAD)+ImgSize);
_lclose(hf);
    if(NumColors!=0)
{                    
hPal=LocalAlloc(LHND,sizeof(LOGPALETTE) + NumColors* sizeof(PALETTEENTRY));
pPal =(LOGPALETTE *)LocalLock(hPal);
pPal->palNumEntries =(WORD) NumColors;
pPal->palVersion    = 0x300;
lpRGB = (LPRGBQUAD)((LPSTR)lpImgData + (DWORD)sizeof(BITMAPINFOHEADER));
for (i = 0; i < NumColors; i++) {
pPal->palPalEntry[i].peRed=lpRGB->rgbRed;
pPal->palPalEntry[i].peGreen=lpRGB->rgbGreen;
pPal->palPalEntry[i].peBlue=lpRGB->rgbBlue;
pPal->palPalEntry[i].peFlags=(BYTE)0;
lpRGB++;
}
hPalette=CreatePalette(pPal);
LocalUnlock(hPal);
LocalFree(hPal);
}
hDc=GetDC()->m_hDC;
if(hPalette){
        hPrevPalette=SelectPalette(hDc,hPalette,FALSE);
RealizePalette(hDc);
}
hBitmap=CreateDIBitmap(hDc, (LPBITMAPINFOHEADER)lpImgData, (LONG)CBM_INIT,
(LPSTR)lpImgData+sizeof(BITMAPINFOHEADER) +NumColors*sizeof(RGBQUAD),
(LPBITMAPINFO)lpImgData, DIB_RGB_COLORS);
if(hPalette && hPrevPalette){
SelectPalette(hDc,hPrevPalette,FALSE);
RealizePalette(hDc);
}

::ReleaseDC(this->m_hWnd, hDc);
GlobalUnlock(hImgData); CRect rect;
GetWindowRect(&rect);
GetParent()->ScreenToClient(rect);
rect.right = rect.left + bi.biWidth;
rect.bottom = rect.top + bi.biHeight;
MoveWindow(&rect);
Invalidate();

return true;
}void CFSBitmap::Free()
{
if(hBitmap!=NULL){     
DeleteObject(hBitmap);
hBitmap=NULL;
}
if(hPalette!=NULL){                     
DeleteObject(hPalette);
hPalette=NULL;
}
if(hImgData!=NULL){
GlobalUnlock(hImgData);
GlobalFree(hImgData);  
hImgData=NULL;
}
}

Answer 3

CxImage 非常好用的类http://baike.baidu.com/view/2126624.htm

Answer 4

VS 下用自带的CImage类就很方便。