Xerox Paris, a document system Support & Software User Guide
Chapter 1
40
The Paris Spooler Technical Manual
XPD Graphics Compression commands
Paris offers you the option to compress graphics using XPD Graphics
Compression commands. Using graphics compression will make the output files
created by Paris considerably smaller, an important benefit when color
applications are involved.
Compression commands. Using graphics compression will make the output files
created by Paris considerably smaller, an important benefit when color
applications are involved.
Using XPD Graphics Compression commands
Graphics compression is activated in Paris via an XPD entry in the XPD file as
follows: *XPDGrafCompression type, where type can be either None; RLE or
Flate. Using either RLE or Flate invokes the graphics handling system.
follows: *XPDGrafCompression type, where type can be either None; RLE or
Flate. Using either RLE or Flate invokes the graphics handling system.
None
Using ‘None’ restores the original Paris graphics handling system. The benefit of
size reduction to output files is not available using this type.
size reduction to output files is not available using this type.
RLE
Using RLE achieves a 20% reduction in size of simple images (e.g. black and
white), less on color graphics.
white), less on color graphics.
RLE can be used with PostScript Level 2 printers and up. It has little effect on
increasing Paris Engine throughput.
increasing Paris Engine throughput.
Flate
Flate uses Zlib flate/deflate compression and can be used with PostScript Level 3
printers only. It is effective with all types of graphics, with compression typically
around 65% on color images and 85% on simpler images, such as black and white.
printers only. It is effective with all types of graphics, with compression typically
around 65% on color images and 85% on simpler images, such as black and white.
Flate has significant effect on increasing Paris Engine throughput. (NOTE: It is
recommended that *XPDManageGrafs: Download is used with Flate so that
graphics are compressed at the beginning of the job, thus avoiding the need for
graphics to be compressed every time they are used.)
recommended that *XPDManageGrafs: Download is used with Flate so that
graphics are compressed at the beginning of the job, thus avoiding the need for
graphics to be compressed every time they are used.)
For example, to enable zlib deflate/flate compression, the following line would be
added to the XPD: *XPDGrafCompression: Flate
added to the XPD: *XPDGrafCompression: Flate
If the XPDGrafCompression keyword is not present within the file, then the
default is None.
default is None.