Modular screening

This page applies to Harlequin v14.0r0 and later; both Harlequin Core and Harlequin MultiRIP.

The Core RIP publishes an API for screening rasters that allows you to supply code (screening modules) to apply your own halftoning algorithms. The interface is known as the modular screening API.

Screening modules are principally used to perform raster halftoning, but they can also choose to receive object type information for the raster to enable them to vary their screening techniques accordingly. In fact, a module can implement any kind of screening, including kinds not supported by standard screening or other Harlequin extensions, including error diffusion, stochastic, and object type and color dependent algorithms.

Areas of the raster halftoned using the screening interfaces are referred to as modular-screened to differentiate them from the RIP’s built-in screening.

In Harlequin Core, you will need to set the Halftone page device parameter to /Modular. To direct the RIP to screen objects with a modular screen, use GGS extension, HalftoneType 100.

For technical information about the API, see Halftone module interface.