feComponentTransfer Filter Element

This filter primitive performs component-wise remapping of data:

R' = feFuncR( R )
G' = feFuncG( G )
B' = feFuncB( B )
A' = feFuncA( A )

for every pixel. It allows operations like brightness adjustment, contrast adjustment, color balance or thresholding.

The calculations are performed on non-premultiplied color values. If the input graphics consists of premultiplied color values, those values are automatically converted into non-premultiplied color values for this operation. (Note that the undoing and redoing of the premultiplication can be avoided if feFuncA is the identity transform and all alpha values on the source graphic are set to 1.)

For common properties see: Filter Primitives Overview

SVG Attributes

  • in – (see in attribute)

Methods

feFuncR(type_, **extra)

create and add a transfer function for the red component of the input graphic

feFuncG(type_, **extra)

create and add a transfer function for the green component of the input graphic

feFuncB(type_, **extra)

create and add a transfer function for the blue component of the input graphic

feFuncA(type_, **extra)

create and add a transfer function for the alpha component of the input graphic

Parameters for feFuncX() Methods

  • type'identity | table | discrete | linear | gamma'

    see: http://www.w3.org/TR/SVG11/filters.html#feComponentTransferTypeAttribute

  • tableValues(list of <number>s)

    When type = 'table', the list of <number>s v0,v1,...vn, separated by white space and/or a comma, which define the lookup table. An empty list results in an identity transfer function.

  • slope<number>

    When type = 'linear', the slope of the linear function.

  • intercept<number>

    When type = 'linear', the intercept of the linear function.

  • amplitude<number>

    When type = 'gamma', the amplitude of the gamma function.

  • exponent<number>

    When type = 'gamma', the exponent of the gamma function.

  • offset<number>

    When type = 'gamma', the offset of the gamma function.