一个VC轮廓提取的问题

[zyf19871205]

那位大侠指点我一下下面这一句代码是什么意思：if((cur==0)||(cur==9))，为什么cur还会有等于9的时候
BOOL CDib::OutlineDIB(HDIB hDib)
{
LONG x,y;
int num;
int nw,n,ne,w,e,sw,s,se;
WaitCursorBegin();
HDIB hNewDib = NULL;
WORD wBitCount = DIBBitCount(hDib);
//将图像转化成24位图像，然后再处理
HANDLE h;
PLOGPALETTE plogPal;
h = GlobalAlloc(GHND, sizeof(DWORD) + sizeof(PALETTEENTRY)*256);
if (! h) return FALSE;
plogPal = (PLOGPALETTE)GlobalLock(h);
if (! plogPal) return FALSE;
plogPal->palVersion=PALVERSION;
plogPal->palNumEntries=256;
plogPal->palPalEntry[0].peGreen= 0;
plogPal->palPalEntry[0].peBlue= 0;
plogPal->palPalEntry[0].peRed= 0;
plogPal->palPalEntry[0].peFlags=NULL;
plogPal->palPalEntry[1].peGreen=255;
plogPal->palPalEntry[1].peBlue=255;
plogPal->palPalEntry[1].peRed=255;
plogPal->palPalEntry[1].peFlags=NULL;
HPALETTE hpl=CreatePalette(plogPal);
HPALETTE palold=NULL;
if (wBitCount != 8)
{
if(wBitCount!=24)
{
CPalette* Cpal=GetPalette();
palold=(HPALETTE)Cpal->GetSafeHandle();
}
hNewDib = ConvertDIBFormat(hDib,8, hpl);
}
else
hNewDib = ConvertDIBFormat(hDib,8, hpl);

if (! hNewDib)
{
WaitCursorEnd();
return FALSE;
}
//新的位图属性
WORD wDIBWidth = (WORD)DIBWidth(hNewDib);
WORD wDIBHeight = (WORD)DIBHeight(hNewDib);
WORD wBytesPerLine = (WORD)BytesPerLine(hNewDib);
DWORD dwImageSize = wBytesPerLine * wDIBHeight;
//锁定要处理的位图数据
HGLOBAL hFilteredBits = GlobalAlloc(GHND, dwImageSize);
if (!hFilteredBits)
{
WaitCursorEnd();
return FALSE;
}
LPBYTE lpPtr = (LPBYTE)GlobalLock(hFilteredBits);
LPBYTE lpDIB = (LPBYTE)GlobalLock(hNewDib);
LPBYTE lpDIBits = FindDIBBits(lpDIB);
unsigned char cur;
memcpy(lpPtr,lpDIBits, dwImageSize);
//开始处理
for (y=1;y<wDIBHeight-1;y++)
{
lpPtr=(unsigned char *)lpDIBits+(dwImageSize-wBytesPerLine-y*wBytesPerLine);
for (x=1;x<wDIBWidth-1;x++)
{
cur=(unsigned char)*(lpPtr+x);
if((cur==0)||(cur==9))//************************不懂不懂*****************
{
w=(unsigned char)*(lpPtr+x-1);
e=(unsigned char)*(lpPtr+x+1);
nw=(unsigned char)*(lpPtr+x+wBytesPerLine-1);
n=(unsigned char)*(lpPtr+x+wBytesPerLine);
ne=(unsigned char)*(lpPtr+x+wBytesPerLine+1);
sw=(unsigned char)*(lpPtr+x-wBytesPerLine-1);
s=(unsigned char)*(lpPtr+x-wBytesPerLine);
se=(unsigned char)*(lpPtr+x-wBytesPerLine+1);
num=nw+n+ne+w+e+sw+s+se;
//如果不是边界，将值设为9
if(num%9==0)
*(lpPtr+x)=(unsigned char)9;
}
}
}
for (y=1;y<wDIBHeight-1;y++)
{
lpPtr=(unsigned char *)lpDIBits+(dwImageSize-wBytesPerLine-y*wBytesPerLine);
for (x=1;x<wDIBWidth-1;x++)
{
cur=(unsigned char)*(lpPtr+x);
//如果不是边界，将值设为1,为白色
if(cur==9)
*(lpPtr+x)=(unsigned char)1;
}
}
//重建位图，变换回原来的位数
GlobalUnlock(hFilteredBits);
GlobalFree(hFilteredBits);
GlobalUnlock(hNewDib);
HDIB hTmp = NULL;
if (wBitCount != 8)
{
if(wBitCount ==24)
hTmp = ConvertDIBFormat(hNewDib, wBitCount, NULL);
else
hTmp = ConvertDIBFormat(hNewDib, wBitCount, palold);
}
else
hTmp = CopyHandle(hNewDib);
GlobalUnlock(h);
GlobalFree(h);
GlobalFree(hNewDib);
DWORD dwSize = GlobalSize(hTmp);
//将原先的位图数据替换成处理后的位图数据
memcpy((LPBYTE)GlobalLock(hDib), (LPBYTE)GlobalLock(hTmp), dwSize);
GlobalUnlock(hTmp);
GlobalUnlock(hDib);
WaitCursorEnd();
return TRUE;
}

[lgstudyvc]

加断点去看吧,看何时为9