void TfrmMain::ImageRect(Graphics::TBitmap *pBitmap) //宣告函數
{
int xt=pBitmap->Width; //Left
int xb=0;              //Right
int yt;                //Top
int yb;                //Bottom
int threshold=218;     //2值化基準值,依背景不同更變
bool check_yt=true;
int b,g,r,gray;
Byte *ptr;    for (int y = 0; y < pBitmap->Height; y  )
   {
     ptr = (Byte *)pBitmap->ScanLine[y];
  for (int x = 0; x < pBitmap->Width; x  )
     {
       b=ptr[x*3];
       g=ptr[x*3 1];
       r=ptr[x*3 2];
       gray=(0.299*r 0.587*g 0.114*b);
       if(gray>threshold)
       gray=255;
       else
       gray=0;
    if (gray!=0)
       {
     if(check_yt)
        {
        yt=y;
        check_yt=false;
        }
        yb=y;
        if(xxb) xb=x;
       }
     }
   }
TRect TheRect,ImgRect;
TheRect = Rect(xt,yt,xb,yb);
ImgRect = Rect(0, 0, xb-xt 1, yb-yt 1);
pBitmap->Canvas->CopyRect(ImgRect,pBitmap->Canvas,TheRect);
pBitmap->Width=xb-xt 1;
pBitmap->Height=yb-yt 1;    }