else
        begin
          _GetMediaContrastRGB(Bitmap, mR, mG, mB);
          t := (mR * gRedToGrayCoef + mG * gGreenToGrayCoef + mB * gBlueToGrayCoef) div 100;
          for i := 0 to Bitmap.Height-1 do
          begin
            pxrgb := Bitmap.Scanline[i];
            pxb := mask.Scanline[i+1]; inc(pxb);
            for j := 0 to Bitmap.Width-1 do
            begin
              with pxrgb^ do
                c := (r * gRedToGrayCoef + g * gGreenToGrayCoef + b * gBlueToGrayCoef) div 100;
              if c>=t then
                pxb^ := 255
              else
                pxb^ := 0;
              inc(pxrgb);
              inc(pxb);
            end;
          end;
        end;
      end;
    else
      for i := 0 to Bitmap.Height-1 do
      begin
        pxb := mask.Scanline[i+1]; inc(pxb);
        for j := 0 to Bitmap.Width-1 do
        begin
          with Bitmap.Pixels[j,i] do
            c := (r * gRedToGrayCoef + g * gGreenToGrayCoef + b * gBlueToGrayCoef) div 100;
          if c>=200 then
            pxb^ := 255
          else
            pxb^ := 0;
          inc(pxb);
        end;
      end;
  end;