Effect Nodes

class libavg.avg.BlurFXNode(radius=1.0)

Bases: libavg.avg.FXNode

Blurs the node it is applied to. Corresponds to the Gaussian Blur effect in Photoshop.

Not supported under minimal shaders. Programs can call Player.areFullShadersSupported() to ensure support.

radius

The width of the blur. This corresponds to the radius parameter of photoshop.

class libavg.avg.ChromaKeyFXNode

Bases: libavg.avg.FXNode

Chroma keying is the process of removing a uniformly colored background from an image. The background is then replaced with a different image or video. Actors are filmed in front of a blue- or green-colored background and chroma keying is used to insert a different background.

The ChromaKeyFXNode implements a high-quality realtime chroma key (greenscreen or bluescreen) effect. It replaces all pixels that are similar to a configured key color with transparency and can account for noise in the background area as well as remove color spill from the background to the foreground. All of the parameters can be manipulated for test purposes using the avg_chromakey.py script. The effect is carried out in the HSL colorspace (http://en.wikipedia.org/wiki/HSL_and_HSV).

Not supported under minimal shaders. Programs can call Player.areFullShadersSupported() to ensure support.

color

The color to key out. Pixels of this and similar colors are made transparent.

erosion

Removes single non-keyed-out pixels in larger transparent areas. Values > 1 remove larger areas. Useful for removing camera noise.

htolerance

Hue tolerance for the key color.

ltolerance

Lightness tolerance for the key color.

softness

softness > 0 causes pixels with a color close to the keyed-out colors to become partially transparent. Greater values increase this effect.

spillthreshold

Often, people in greenscreen studios aquire a greenish tint. Spill removal works against this by desaturating pixels that are close to the key color. Larger values cause more desaturation.

stolerance

Saturation tolerance for the key color.

class libavg.avg.FXNode

Bases: Boost.Python.instance

Base class for GPU-based effects. These effects can be added to any RasterNode by calling RasterNode.setEffect().

class libavg.avg.HueSatFXNode(hue=0.0, saturation=0.0, lightness=0.0, colorize=False)

Bases: libavg.avg.FXNode

Color correction filter that works by converting pixels to the hsl color space (http://en.wikipedia.org/wiki/HSL_and_HSV), changing the values there and converting back to rgb. Can be used to change hue, saturation and lightness of a node. Corresponds to the Photoshop Hue/Saturation dialog.

colorize

If colorize is True, all colors will be tinted according to the current hue value. Otherwise, hue is treated as a difference value.

hue

Used to get/set the color angle in degrees. Effective values are 0..360 or -180..180, depending on the colorize value.

lightness

Set lightness offset. Adds a per pixel offset in brightness. Values range from -100 to 100, with -100 being very dark and 100 very bright.

saturation

Set saturation of Node. In colorize mode, this is the overall image saturation in the range 0..100, with 0 being greyscale and 100 very oversaturated. If colorize is false, the attribute is an offset from -100 to 100.

class libavg.avg.InvertFXNode

Bases: libavg.avg.FXNode

Color Invert Effect. Inverts the brightness of nodes that it is attached to.

class libavg.avg.NullFXNode

Bases: libavg.avg.FXNode

Do-nothing effect. Exists primarily as aid in debugging libavg.

class libavg.avg.ShadowFXNode(offset=(0, 0), radius=1.0, opacity=1.0, color="FFFFFF")

Bases: libavg.avg.FXNode

Adds a shadow behind the node.

Not supported under minimal shaders. Programs can call Player.areFullShadersSupported() to ensure support.

offset

An adjustment to the shadow’s position behind the node in pixels.

radius

The blur radius of the shadow.

opacity

The opacity of the shadow.

color

The shadow color.