Delphi二值图片去杂点问题

由于二值图点的RGB是0或者255，可以根据一个点A的RGB值 与周围的8个点的RBG 比较  设定一个值N（0 <N <8）  当A的RGB值与周围8个点的RGB相等数小于N时 此点为噪点改变其RGB值即可 .

附上一段代码 没具体测试。

 
   procedure 
    ClearNoise(Bitmap:TBitmap;N:Integer); 
 
   var 
    
  piexl : tcolor; 
  nearDots,x,y,RGBz : integer; 
 
   begin 
    
  bitmap.Canvas.Pixels[ 
   0 
   , 
   0 
   ]: 
   = 
   rgb( 
   255 
   ,  
   255 
   ,  
   255 
   ); 
  bitmap.Canvas.Pixels[bitmap.Width  
   - 
     
   1 
   ,bitmap.Height  
   - 
     
   1 
   ]: 
   = 
   rgb( 
   255 
   ,  
   255 
   ,  
   255 
   ); 
   
   for 
    x : 
   = 
     
   1 
     
   to 
    bitmap.Width  
   - 
   2 
     
   do 
    
   
   for 
    y : 
   = 
     
   1 
     
   to 
    bitmap.Height 
   - 
   2 
     
   do 
    
   
   begin 
    
    piexl : 
   = 
    bitmap.Canvas.Pixels[x,y]; 
    RGBz : 
   = 
    getrvalue(piexl); 
     
   if 
    (RGBz  
   = 
     
   0 
   )  
   then 
    
     
   begin 
    
      nearDots : 
   = 
     
   0 
   ;   
   // 
   判断周围8个点RGB是否相等 
       
   if 
    (getrvalue(bitmap.Canvas.Pixels[x  
   - 
     
   1 
   , y  
   - 
     
   1 
   ])  
   = 
    RGBz)  
   then 
    nearDots: 
   = 
   nearDots 
   + 
   1 
    ; 
       
   if 
    (getrvalue(bitmap.Canvas.Pixels[x, y  
   - 
     
   1 
   ])  
   = 
    RGBz)  
   then 
    nearDots: 
   = 
   nearDots 
   + 
   1 
    ; 
       
   if 
    (getrvalue(bitmap.Canvas.Pixels[x  
   + 
     
   1 
   , y  
   - 
     
   1 
   ])  
   = 
    RGBz)  
   then 
    nearDots: 
   = 
   nearDots 
   + 
   1 
    ; 
       
   if 
    (getrvalue(bitmap.Canvas.Pixels[x  
   - 
     
   1 
   , y])  
   = 
    RGBz)  
   then 
    nearDots: 
   = 
   nearDots 
   + 
   1 
    ; 
       
   if 
    (getrvalue(bitmap.Canvas.Pixels[x  
   + 
     
   1 
   , y])  
   = 
    RGBz)  
   then 
    nearDots: 
   = 
   nearDots 
   + 
   1 
    ; 
       
   if 
    (getrvalue(bitmap.Canvas.Pixels[x  
   - 
     
   1 
   , y  
   + 
     
   1 
   ])  
   = 
    RGBz)  
   then 
    nearDots: 
   = 
   nearDots 
   + 
   1 
    ; 
       
   if 
    (getrvalue(bitmap.Canvas.Pixels[x, y  
   + 
     
   1 
   ])  
   = 
    RGBz)  
   then 
    nearDots: 
   = 
   nearDots 
   + 
   1 
    ; 
       
   if 
    (getrvalue(bitmap.Canvas.Pixels[x  
   + 
     
   1 
   , y  
   + 
     
   1 
   ] ) 
   = 
    RGBz)  
   then 
    nearDots: 
   = 
   nearDots 
   + 
   1 
    ; 
       
   if 
    (nearDots  
   < 
    N)  
   then 
     bitmap.Canvas.Pixels[x,y]: 
   = 
   rgb( 
   255 
   ,  
   255 
   ,  
   255 
   ) 
     
   end 
    
     
   else 
    
      bitmap.Canvas.Pixels[x,y]: 
   = 
   rgb( 
   255 
   ,  
   255 
   ,  
   255 
   ); 
   
   end 
   ; 
 
   end 
   ;