Image sharpening is a powerful tool for emphasizing texture and drawing viewer focus. It's also required of any
digital photo at some point — whether you're aware it's been applied or not. Digital camera sensors and lenses
always blur an image to some degree, for example, and this requires correction. However, not all sharpening
techniques are created equal. When performed too aggressively, unsightly sharpening artifacts may appear. On the
other hand, when done correctly, sharpening can often improve apparent image quality even more so than upgrading
to a high-end camera lens. Human perception is highly sensitive to edges and fine details of an image, and since they
are composed primarily by high frequency components, the visual quality of an image can be enormously degraded
if the high frequencies are attenuated or completed removed. In contrast, enhancing the high-frequency components
of an image leads to an improvement in the visual quality. Image sharpening refers to any enhancement technique
that highlights edges and fine details in an image. Image sharpening is widely used in printing and photographic
industries for increasing the local contrast and sharpening the images.