
PostScript file plugin V1.04 for the GIMP Peter Kirchgessner, 23-Dec-97
========================================= e-mail: pkirchg@aol.com
                                          WWW   : http://members.aol.com/pkirchg

Here is a PostScript file plugin for the GIMP.
The plugin will not work with GIMP V 0.54 !
In the directory

    ftp://members.aol.com/pkirchg/pub/gimp

you will find the following files:

    ps.txt                    : this document
    ps.tgz                    : gzipped tarfile with source
    ps.linux.386.elf.tgz      : gzipped tarfile with Linux executable

News:
  V 1.04, 23-Dec-97:
    add Encapsulated PostScript output and device independant preview
    add achanges that came with gimp V 0.99.16
  V 1.02:
    support for anti-aliasing (George White).
    no progress bars for non-interactive mode.
    new procedure file_ps_load_setargs to set
    load arguments non-interactively.
    Check for GS_OPTIONS. If not set, use at least "-dSAFER".
  V 1.01:
    parse rc file (changes font in dialogue).
  V 1.00:
    clip everything outside BoundingBox.
    support for multi page documents.
    PDF input.

The PostScript file plugin handles reading and writing of PostScript files.
For interpreting PostScript, ghostscript must be installed. The gs-
executable must include the pbmraw, pgmraw, ppmraw and pnmraw devices.
At least the ppmraw device is necessary.
If ghostscript supports PDF reading, the plugin can also read PDF.
For writing PostScript, the following image-operators are used:

   colorimage (indexed and RGB images)
   image (gray images)

The colorimage operator is available with PostScript Level II,
but it should also be available on Color PostScript Printers
with PostScript Level I.
For usage of antialiasing, ghostscript must support the
-dTextAlphaBits and -dGraphicsAlphaBits commandline arguments for
the ppm-devices. These are available with V 4.01, but maybe also
with V 3.65. For PDF-input, anti-aliasing seems not to work
(at least not with gs V 4.01). The -d...AlphaBits options are not
used by the plug-in, when the anti-aliasing options are set to "none".
The path to locate ghostscript can be changed by setting
the environment variable GS_PROG to point to the executable. 
If additional arguments must be passed to ghostscript, please
use the environment variable GS_OPTIONS. This is evaluated by
ghostscript itself. If GS_OPTIONS is not set, the plug-in adds
-dSAFER automatically.
The procedure file_ps_load_setargs can be used within script-fu to
specify the interpretation options for the plug-in. The arguments to
file_ps_load_setargs are:

    PARAM_INT32: Resolution to interprete image (dpi)
    PARAM_INT32: Desired width
    PARAM_INT32: Desired height
    PARAM_INT32: 0: Use width/height, 1: Use BoundingBox
    PARAM_STRING: Pages to load (e.g.: 1,3,5-7)
    PARAM_INT32: coloring. 4: b/w, 5: grey, 6: colour image, 7: automatic
    PARAM_INT32: text antialiasing: 1: none, 2: weak, 4: strong
    PARAM_INT32: graphics antialiasing: 1: none, 2: weak, 4: strong
 
When saving PostScript, Encapsulated PostScript can be choosen.
Also a device independant preview can be added to the output file.
The size of the prview can be choosen, but it can not exceed
the size of the original image. The preview consists of a b/w-bitmap
that shows a representation of the image. 

Installation:
To tell the GIMP about the PostScript-file-plugin, copy the ps-executable
to /usr/local/lib/gimp/0.99.x/plug-ins .

Bug reports or suggestions should be e-mailed to pkirchg@aol.com
