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...apply a negative filter to a bitmap?
Autor: mehrdad farrokhmanesh
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Tip Rating (11):  
     



var
  
b: tbitmap;
  s: string;
  x, y: Integer;
  p: pbytearray;
  image1: TImage;
  
procedure LoadBitmap;
begin
  if 
opendialog1.Execute then
  begin
    
b := tbitmap;
    s := opendialog1.FileName;
    b.loadfromfile(s);
    image1.Canvas.draw(0,0,b);
  end;
end;

procedure ApplyNegativeFilter;
begin
  
image1.Height := b.Height;
  image1.Width  := b.Width;
  for y := 0 to b.Height - 1 do
  begin
    
p := b.scanline(y);
    for x := 0 to b.Width - 1 do
    begin
      
(([image1.Canvas.pixels[x, y] := rgb(255 - (p[x * 3) - 4]), 255 - (p[x * 3) - 2]),
        255 - (p[x * 3) - 3]));
      end;
    end;
end;


 

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