IDistort node

This documentation is for version 2.0 of IDistort (net.sf.openfx.IDistort).

Description

Distort an image, based on a displacement map.

The U and V channels give the offset in pixels in the destination image to the pixel where the color is taken. For example, if at pixel (45,12) the UV value is (-1.5,3.2), then the color at this pixel is taken from (43.5,15.2) in the source image. This plugin concatenates transforms upstream, so that if the nodes upstream output a 3x3 transform (e.g. Transform, CornerPin, Dot, NoOp, Switch), the original image is sampled only once.

This plugin concatenates transforms upstream.

Inputs

Input	Description	Optional
Source		No
UV		No
Mask		Yes

Controls

Parameter / script name	Type	Default	Function
U Channel / channelU	Choice	Color.R	Input U channel from UV. Color.R (uk.co.thefoundry.OfxImagePlaneColour.R): R channel from input UV Color.G (uk.co.thefoundry.OfxImagePlaneColour.G): G channel from input UV Color.B (uk.co.thefoundry.OfxImagePlaneColour.B): B channel from input UV Color.A (uk.co.thefoundry.OfxImagePlaneColour.A): A channel from input UV 0: 0 constant channel 1: 1 constant channel
V Channel / channelV	Choice	Color.G	Input V channel from UV. Color.R (uk.co.thefoundry.OfxImagePlaneColour.R): R channel from input UV Color.G (uk.co.thefoundry.OfxImagePlaneColour.G): G channel from input UV Color.B (uk.co.thefoundry.OfxImagePlaneColour.B): B channel from input UV Color.A (uk.co.thefoundry.OfxImagePlaneColour.A): A channel from input UV 0: 0 constant channel 1: 1 constant channel
Alpha Channel / channelA	Choice	Color.A	Input Alpha channel from UV. The Output alpha is multiplied by this value. If “Unpremult UV” is checked, the UV values are divided by alpha. Color.R (uk.co.thefoundry.OfxImagePlaneColour.R): R channel from input UV Color.G (uk.co.thefoundry.OfxImagePlaneColour.G): G channel from input UV Color.B (uk.co.thefoundry.OfxImagePlaneColour.B): B channel from input UV Color.A (uk.co.thefoundry.OfxImagePlaneColour.A): A channel from input UV 0: 0 constant channel 1: 1 constant channel
Unpremult UV / unpremultUV	Boolean	Off	Unpremult UV by Alpha from UV. Check if UV values look small for small values of Alpha (3D software sometimes write premultiplied UV values).
UV Offset / uvOffset	Double	U: 0 V: 0	Offset to subtract from the U and V channel (useful if these were stored in a file that cannot handle negative numbers)
UV Scale / uvScale	Double	U: 1 V: 1	Scale factor to apply to the U and V channel after subtracting the offset (useful if these were stored in a file that can only store integer values)
Filter / filter	Choice	Cubic	Filtering algorithm - some filters may produce values outside of the initial range (*) or modify the values even if there is no movement (+). Impulse (impulse): (nearest neighbor / box) Use original values. Box (box): Integrate the source image over the bounding box of the back-transformed pixel. Bilinear (bilinear): (tent / triangle) Bilinear interpolation between original values. Cubic (cubic): (cubic spline) Some smoothing. Keys (keys): (Catmull-Rom / Hermite spline) Some smoothing, plus minor sharpening (*). Simon (simon): Some smoothing, plus medium sharpening (*). Rifman (rifman): Some smoothing, plus significant sharpening (*). Mitchell (mitchell): Some smoothing, plus blurring to hide pixelation (*)(+). Parzen (parzen): (cubic B-spline) Greatest smoothing of all filters (+). Notch (notch): Flat smoothing (which tends to hide moire’ patterns) (+).
Clamp / clamp	Boolean	Off	Clamp filter output within the original range - useful to avoid negative values in mattes
Black outside / black_outside	Boolean	Off	Fill the area outside the source image with black
Use Source RoD / useRoD	Boolean	Off	Use the region of definition of the source as the source format.
(Un)premult / premult	Boolean	Off	Divide the image by the alpha channel before processing, and re-multiply it afterwards. Use if the input images are premultiplied.
Invert Mask / maskInvert	Boolean	Off	When checked, the effect is fully applied where the mask is 0.
Mix / mix	Double	1	Mix factor between the original and the transformed image.