A great addition to B4J would be support for the JavaFX ColorAdjustclass. I could perhaps look at writing a library but I don't really know how to properly implement it.
It should be quite simple to access this API with JavaObject.
Something like:
B4X:
Dim colorAdjust As JavaObject
colorAdjust.InitializeNewInstance("javafx.scene.effect", null)
colorAdjust.RunMethod("setContrast", Array(0.1))
...
Dim jiv As JavaObject = ImageView1
jiv.RunMethod("setEffect", Array(colorAdjust))