InterpolateAllImages, InterpolateAllMasks (user param)

This page applies to Harlequin v13.1r0 and later; both Harlequin Core and Harlequin MultiRIP

[PDF2] section 8.9.5.3 (and [RB3] 4.10.5) mentions the image dictionary entry /Interpolate, which is a boolean giving a hint to PDF/PS consumers that the image should be interpolated. Our /InterpolateAllImages setting controls whether this hint is used to turn on image filtering, and whether image filtering is forced on or off. This resamples an image to match output resolution unless the image is already at that resolution. This can be upsampling by interpolation (when image resolution is too low) or downsampling by averaging (when image resolution is too high).

The /InterpolateAllImages and /InterpolateAllMasks user parameters are four-state values, which are set with a simple name, one of /DefaultTrue , /DefaultFalse , /ForceTrue , /ForceFalse.

To turn interpolation on for all images, you would use:

<</InterpolateAllImages /ForceTrue>> setuserparams

To turn image interpolation on for only those images which specify /Interpolate true in an image dictionary, you would use:

<</InterpolateAllImages /DefaultFalse>> setuserparams

Default: ForceFalse (image and mask interpolation is disabled)