I.R.I.S. Readiris 14 for Windows User Guide - Manual (Page 127)

Section 9: Saving Documents
134
XPS - intelligent High-Quality Compression
In Readiris you also have the possibility to compress your XPS
documents. Refer to the separate section Compressing XPS
documents for more information.
C
OMPRESSING
XPS D
OCUMENTS
The XPS documents you generate with Readiris can be hyper-
compressed by means of iHQC. iHQC stands for intelligent High-
Quality Compression, I.R.I.S.' proprietary, efficient compression
technology. iHQC is to images what MP3 is to music and what
DivX is to movies.
To generate compressed XPS documents:

Click the Format button in the Output group.