[[cHackAll]]

Vaya amigo seoane veo que te has adelantado, sin embargo pongo una funcion mas rápida:

Código Delphi [-]
procedure TForm1.Button1Click(Sender: TObject);
var
 Count: Cardinal;
 Pixel: PCardinal;
begin
 Count := Image1.Picture.Width * Image1.Picture.Height;
 Image1.Picture.Bitmap.PixelFormat := pf32bit;
 with Image1.Picture.Bitmap do
  Pixel := ScanLine[Height - 1];
 while LongBool(Count) do
  begin
//   Pixel^ := Pixel^ and $FF0000; // Red
//   Pixel^ := Pixel^ and $00FF00; // Green
   Pixel^ := Pixel^ and $0000FF; // Blue
   Inc(Pixel);
   Dec(Count);
  end;
end;

Solo por que me daria pena desperdiciar el code.

Saludos