PDF Functions
PDF Functions
PDF functions (ISO 32000-1:2008, §7.10) are mathematical mappings from input values to output values, used in shading patterns, color space transforms, and transfer functions.
PdfFunction
PdfFunction represents a PDF function object. The standard function types are:
- Type 0 — Sampled function (lookup table)
- Type 2 — Exponential interpolation function
- Type 3 — Stitching function (piecewise combination)
- Type 4 — PostScript calculator function
Usage Context
PDF functions are primarily used internally when working with:
- Shading pattern definitions
- Color space transformations
- Soft mask generation
- Halftone spot functions