5.16. Vír a zaškrcení

5.16. Vír a zaškrcení
	5. Filtry zkreslení

5.16.1. Overview

Obrázek 17.94. Example for the Whirl and Pinch filter

Original image

Aktivace filtru

Vír a zaškrcení provádí koncentrické zkreslení obrázku.

„Whirl“ (applying a non-zero Whirl angle) distorts the image much like the little whirlpool that appears when you empty your bath.

„Pinch“, with a nil rotation, can be compared to applying your image to a soft rubber surface and squeezing the edges or corners. If the Pinch amount slider is set to a negative value, it will look as if someone tried to push a round object up toward you from behind the rubber skin. If the Pinch amount is set to a positive value, it looks like someone is dragging or sucking on the surface from behind, and away from you.

	Tip
	Efekt zaškrcení lze někdy použít pro kompenzaci soudkovitého zkreslení objektivu fotoaparátu.

Obrázek 17.95. Illustration

Původní obrázek

Vír

Zaškrcení

5.16.2. Activating the Filter

This filter is found in the main menu under Filters → Distorts → Whirl and Pinch….

5.16.3. Nastavení parametrů

Obrázek 17.96. „Whirl and Pinch“ filter options

Presets, „Input Type“, Clipping, Blending Options, Preview, Merge filter, Split view

	Poznámka
	These options are described in 2 – „Common Features“.

Whirl

The clockwise or counter clockwise angle (-360 to +360). Controls how many degrees the affected part of the image is rotated.

Pinch

The pinch amount (-1 to +1) determines how strongly the affected part of the image is pinched.

Poloměr

Whirlpool width (0.0-2.0). Determines how much of the image is affected by the distortion. If you set Radius to 2, the entire image will be affected. If you set Radius to 1, half the image will be affected. If Radius is set to 0, nothing will be affected (think of it as the radius in a circle with 0 in the center and 1 halfway out).