Sharpen

procedure Sharpen(img: TImage32; radius: Integer = 2; amount: Integer = 10);


Radius range is 1 - 10; amount range is 1 - 50.

Sharpen increases color contrast between adjacent pixels. With larger images, the results of Sharpen are subtle but still noticeable. Where Sharpen can be particularly useful is in improving clarity of images resized to much smaller dimensions (eg smaller sized icons).

See also Unsharp Masking at Wikipedia.

uses Image32, Image32_Extra, Image32_PNG;
...
img := TImage32.Create;
img.LoadFromFile('fruit.png');
Sharpen(img, 3, 30);
img.SaveToFile('fruit_sharp.png');
img.Free;
      
Before:
After: