Grunnleggande innstillingar

Steglengde

Her bestemmer du kor mykje pikslane skal forskyvast for kvar filtergjennomgang. Verdien 10 er nødvendig for å få ei forskyving på 1 piksel. Ein negativ verdi vil føre til at forskyvinga vert i motsett retning i høve til normalen.

Gjentaking

Kor mange gonger filterfunksjonen skal repeterast.

På kantane

Because of displacement, a part of pixels are driven over the borders of layer or selection, and, on the opposite side, pixels places are emptying. The four following options allow you to fix this issue:

Bryt

Det som forsvinn over biletkanten vil dukke opp på motsett side. (Dette er normalinnstillinga).

Smør ut

Emptying places are filled with a spreading of the neighboring image line.

Svart

Dei tomme plassane vert fylt med svart.

Forgrunnsfarge

Dei ledige plassane vert fylt med den forgrunnsfargen som er sett i verktøykassa.

Forskyvingskart

To be listed in this file picker, the displacement map, which should be a grayscale image, must be present on your screen when you call this filter and must have the same size as the original image.

Avanserte innstillingar

Utjamningsstorleik

Once all pixels are displaced, this option scatters them randomly, giving grain to the image. The higher this value (0.00-100.00), the thinner the grain.

Figur 17.317. Med spreiingsstorleik 3,00:

Rotasjonsvinkel

This option sets the displacement angle of pixels according to the slope direction of the gradient. Previous examples have been created with a vertical gradient and a 90° angle: so, pixels were displaced horizontally and nothing went out of the image borders. Here is an example with a 10° angle and 6 iterations:

Figur 17.318. Med vinkel 10° og 6 gjentakingar:

Displacement is made according to a 10° angle against vertical. Pixels going out the lower border on every iteration are going in through the upper border (Wrap option checked), giving a dotted line.

Mellomsteg

Dersom du spesifiserer ein verdi høgare enn > 1 vil forskyvingsvektoren vert rekna ut i fleire steg slik at du har ein betre kontroll med prosessen.

Vektleggingskart

In addition to displacement map, you can add a Magnitude map. This map should also be a grayscale image, with the same size as the source image and which must be present on your screen when you call the filter. This map gives more or less strength to the filter on some parts of the image, according to the gray levels of this magnitude map. Image areas corresponding to white parts of this map will undergo all the strength of the filter. Image areas corresponding to black parts of the map will be spared by the filter. Intermediate gray levels will lessen the filter action on corresponding areas of the image. Use magnitude map must be checked for that.

Figur 17.319. Eksempel med vektlegginskart:

From left to right: original image, displacement map, magnitude map, after applying «Warp» filter. You can see that the black areas of the magnitude map prevent the filter from taking action.

Meir avanserte innstillingar

I dette avsnittet kan du legge til to nye kart, eit overgangskart og eit vektorkart.

	Notat
	For å prøve ut desse innstillingane åleine, må dei andre karta vere einsfarga.

Overgangsskala

Using a gradient map, (this map should also be a grayscale image), the displacement of pixels depends on the direction of grayscale transitions. The Gradient scale option lets you set how much the grayscale variations will influence the displacement of pixels. On every iteration, the filter works on the whole image, not only on the red object: this explains blurredness.

Figur 17.320. Eksempel på bruk av overgangskart

Frå venstre: originalbiletet, overgangskartet, filtrert bilete

In the example above, «Warp» filter is applied with a gradient map (Gradient scale = 10.0). The gradient is oblique, from top left to right bottom. The part of the image corresponding to the gradient is moved obliquely, 90° rotated (Rotation angle 90° in Advanced Options).

Vector magnitude

Med dette kartet er forflyttinga avhengig av vinkelen du set i boksen Vinkel. 0° tilsvarar rett opp. Vektorforstørring bestemmer kor mange pikslar biletet vert flytt i kvar gjennomkøyring.

Figur 17.321. Vector magnitude example

Frå venstre: originalbiletet, forflyttingskartet, filtrert bilete

In the above example, «Warp» filter is applied with a Vector magnitude. Gradient is vertical, from top to bottom. Vector angle is 45°. The image is moved obliquely, 45° to the top left corner. The image is blurred because every iteration works on the whole image, and not only on the red bar.

Vinkel

Vinkel for fast vektor (sjå ovanfor).