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Re: EPS for Windows?

>The EPSI format is
>similar but found only on UNIX platforms.

Well, sort of... This gives me an opportunity to expand on this subject,
sometimes quoting from the Adobe PostScript Reference Manual:

PS = PostScript:
PostScript is not really a page description language, it's a programming
language. A PS file is a program which, when executed (interpreted),
usually draws an image on an output device. This is normally a printer,
but may also be a computer display. Some systems, like Sun Solaris and
NeXT, comes with DPS (Display PostScript) for the purpose of displaying
PS files on-screen without the need for any extra software (like
GhostView) or "preview" images.

EPS = Encapsulated PostScript:
An encapsulated PostScript file is a PostScript language program describing
the appearance of a single page. Typically, the purpose of the EPS file
is to be included, or 'encapsulated,' in another PostScript language page
description. The EPS file can contain any combination of text, graphics,
and images.

The EPS preview image:
It normally requires a PostScript language interpreter to preview an
EPS file on screen. Display PostScript systems allow EPS files to be
dynamically interpreted, insuring the highest-quality, on-screen preview
regardless of scale, rotation, or monitor type. For other environments
where the Display PostScript system is not available, the EPS file format
allows for an optional screen preview image.
The exact format of this screen representation is machine-specific.
That is, each computing environment may have its own preferred preview
image format:
* On Macintosh, a QuickDraw representation of the EPS file can be stored
  as a PICT image in the resource fork of the EPS file.
* In Windows, either a Microsoft Windows Metafile or a TIFF image can be
  included as the screen representation of an EPS file.

The EPSI format:
In addition, a device-independent screen representation called EPSI
exists. This screen preview format is designed to allow EPS files to be
used as an interchange format among widely varied systems. The preview
section of the file is a bitmap represented as ASCII hexadecimal to be
simple and easily transportable. This format is called Encapsulated
PostScript Interchange format, or EPSI.
An EPSI file is truly portable and requires no special code for
decompressing or otherwise understanding the bitmap portion.

Adobe recommends using, or at least supporting, EPSI. Some Macintosh
and Windows applications only allow for platform-specific binary
previews, but other more "well-behaved" software also knows how to
create EPSI previews, for maximum cross-platform compatibility.

In FrameMaker, the EPSI preview format is supported on all platforms.
WMF previews can only be viewed on Windows, TIFF previews can only be
viewed on Windows and Macintosh, and PICT previews can only be viewed
on Macintosh and UNIX. (According to the FM documentation.)
UNIX systems with DPS (Sun, NeXT) can display all EPS files,
regardless of existence or format of the preview.

End of lesson :-)

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Thomas Michanek, [Michagon], Linkoping, Sweden
Documentation Consultant, FrameMaker/UNIX expert
EMAIL:  mailto:Thomas.Michanek@telia.com
WWW:    http://go.to/framers , or go directly to:
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