Two Filter primitives allow the manipulation of colors.
The Color Matrix primitive maps each RGB and Alpha value to a new value. The transformation is described by a 5 × 5 matrix with the bottom row fixed, thus a general transformation is described by a 5 × 4 matrix. The fifth column adds a value that is independent of RGB or Alpha, allowing for nonlinear color correction.
Four types of transformations are defined, of which three are special classes of the first.
A “negative” can be made by setting the RGB diagonal matrix elements (a00, a11, a22) to −1.00 and the top three elements of the fifth column (a04, a14, a24) to 1.00.
Partially implemented, No user interface.
The Component Transfer primitive changes the RGB and Alpha of an object by applying independent functions to each of the RGB and Alpha input values. The following modes for defining the functions are available: Identity, Table, Discrete, Linear, and Gamma.
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