Transcript Slide 1

Synergetic Data Systems, Inc.
Session 6
PostScript® vs. PCL Printing
PostScript is a registered trademark of Adobe Systems Incorporated
Presented by
Allen Miglore
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Why PostScript?
• Through version 6, UnForm supported
PCL5 and PDF output formats. PCL5 was
the language standard for laser printers.
• Starting in 2005, HP reduced support for
PCL5 by eliminating scalable PCL fonts
from some new printer models. All PCL
text was rendered in Courier.
• SDSI chose to develop a PostScript driver.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
PostScript History
• PostScript was developed in the 1980’s by
Adobe, for use in the printing and
typesetting industry.
– The Apple Laserwriter was an early consumer
printer with PostScript.
• PostScript 2 and 3 were released in the
1990’s.
• PostScript is widely supported on laser
printers today – often PostScript 2.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
PostScript vs. PCL5
• PostScript is a programming language
– PCL5 is a page description language
• PostScript is verbose, large print streams
– PCL5 is concise, smaller print streams
• PostScript is extendable to support any
device capability
– PCL5 has a defined specification of device
capabilities
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Key UnForm Differences
• Print stream size increase means longer
transmission times to printer
• Device capabilities are controlled by
commands that differ by printer (duplex,
tray, and bin control)
• Image support differs (eps and jpeg)
• Base fonts are similar, but UnForm also
supports Type1 soft fonts
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Device Capability Example
• In PCL5, a tray selection command was
always ESC +”&l#H”. The UnForm tray
1 command always sent ESC+”&l1H”.
• In PostScript, trays are given names,
which vary by printer, and a tray name is
given PostScript code, which varies by
printer.
• *InputSlot Upper/ Tray 1: "<</ManualFeed
false /MediaPosition 3>> setpagedevice"
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
PPD Files
• Since printer control varies by model, a
configuration file is necessary. Vendors
publish Postscript Printer Definition (PPD)
files for their printers.
• A PPD file is simply a map of capability
names to the code sequences that are
sent to the print stream.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
PPD Files Contain Code
• Vendor PPD files give capabilities names
rather than codes.
– Upper or HighCapacity rather than 1 or 5
• For UnForm, PPD files describe:
– Trays as *InputSlot name: code
– Bins as *OutputBin name: code
– Duplex as *Duplex name: code
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
UnForm Reads PPD Files
• Example: a tray command will cause
UnForm to lookup the code associated
with the *InputSlot definition of that tray.
• Any two PPD files will likely have different
names for the same capability
– None will have codes like PCL (1,4,5,etc.)
• PPD files can be customized to match rule
file names for tray, bin, and duplex.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Locating a PPD - Internet
• Look in the drivers or
software sections of
the manufacturer’s
web site
• Look in the
linixprinting.org web
site:
http://linuxprinting.org/
download/PPD
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Locating a PPD - Windows
• Install drivers for the
printer
– If there’s a choice, be
sure to include
Postscript drivers
• Search for *.ppd
• Copy/paste the ppd
file for your model
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
PPD Files are Always Used
• UnForm comes with two default PPD files
– pcl.ppd – traditional PCL escape sequences
– ps.ppd – based on hp4000.ppd, customized
to show traditional tray and bin codes
• The pcl.ppd file supports the traditional
PCL coded sequence, plus named
sequences modeled on ps.ppd.
• The ps.ppd file supports both as well,
showing how customization can be used.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
PPD File Selection
• UnForm supports PPD files with the –m model
command line option.
– -m hp4000 uses ppd/hp4000.ppd
• Without a –m option, UnForm uses pcl.ppd or
ps.ppd, depending on the driver in use.
• Rule sets can have model-specific sections:
if uf.model$="hp4000"
…
end if
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
During Printing…
• UnForm loads the specified (-m model)
or default ppd file at the start of the job.
• When UnForm encounters a tray, bin, or
duplex command, it looks up the code:
– tray upper looks for the pattern “*InputSlot
*upper*:” and inserts the related code.
– tray 5 looks for the pattern “*InputSlot *5*:”
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Correcting the Mismatch
• UnForm rule files traditionally use PCL
code numbers for printer control.
• PPD files use names rather than PCL
codes to identify printer control features.
• To solve, edit PPD file to provide PCL
codes as synonyms, or change commands
to use PPD names. See ps.ppd.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Image Differences
• Color PostScript printers support EPS and
JPEG files.
• Monochrome PostScript printers support
only EPS, and error on JPEG files.
• Scaling is supported by the printer.
• The attach command is implemented as
an image command scaled to the full
page.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Image Name Substitutions
• If an image has a .pcl or .prn extension,
and the image mode is not color, UnForm
will automatically look for a .eps file.
• If an image command has a .rtl extension,
or the image mode is color, UnForm will
automatically look for a .jpg file.
• Color image mode is indicated by -ci or
-color command line options, or a “color”
image command option.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Image Conversion
• Image Magick can produce EPS or JPEG
if eps= and jpeg= [images] lines are
configured.
• The Windows Support Server can produce
EPS or JPEG images as well.
• The web site image conversion utility can
produce EPS and JPEG images, if you
want pre-created files.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
PostScript Fonts
• There are three standard built-in fonts,
plus two symbol fonts, in every PostScript
device. The three standard fonts come in
normal, bold, italic, and bold-italic.
– Courier, Helvetica, Times-Roman
• Other fonts can be provided using Type1
soft font files.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Internal Font Mapping
• UnForm is designed to select fonts by a
PCL font number. In ufparam.txt, names
are mapped to numbers in the [fonts]
section.
• For PostScript, font numbers are mapped
in the [psmap] section to a font name
found in the psfont directory:
– 4101=Times-Roman,Times-Bold,Times-Italic,TimesBoldItalic
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
The psfont Directory
• Each PostScript font has a .afm file, and
non-internal fonts have a .pfa or .pfb file.
• The .afm file stores character size metrics
• The .pfa/.pfb files are soft fonts that can be
downloaded with jobs that use them.
• A Type1 font will provide the above files.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Type1 Font Example: MICR
• In ufparam.txt, in the [psmap], is this line:
MICR=15002
• In the psfont directory are these files:
MICR.afm
MICR.pfa
MICR.pfb
• A text command using font 15002 will
produce MICR output.
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20
Questions
• Answers
Intelligent Tools
SDSI Technical Conference 2007 ■ Sacramento, CA USA ■ October 18-20