XWPICK - X Windows Image Pick up Utility.


GENERAL INFO 
============

Xwpick lets you pick an image from an arbitrary window or rectangular
area of an X Window (DEC Window) server and write it to a file in a
variety of formats. 

Why xwpick?

 o  Xwpick is convenient in use. The onmipresent blinking rectangle
    surrounding the area to be picked and involment of the keyboard
    input in addition to the mouse help to get rid of numerous parameters,
    nevertheless satisfying in quite a natural way the most common needs
    of users, namely, picking an image from a selected window or from
    an arbitrary rectangular area and a possibility to  change the
    selected image just before outputing to a file.

    Xwpick also allows to pick images from pop-up menus, which are on the
    screen only when the mouse button is pressed and disappear immediately
    after the button is released.

 o  Xwpick can output images in various formats: different PostScripts,
    GIF, PCX (IBM PC), PICT (Macintosh), PPM (PBM Plus).

 o  Xwpick runs not only on UNIX platforms, but on OpenVMS (VAX/Alpha)
    as well.

 o  Xwpick uses the Lempel-Ziv Welch (LZW) compression algorithm for 
    image encoding in PostScript, thus producing very compact files:
    3-5 time less than files produced with Run Length Encoding (RLE) and
    10-30 times less than files produced without compression.

    PostScipt files produced by XWPICK automatically understand on what
    kind of printer they are being output. On level 2 PostScript printers
    the native LZW/ASCII85 decoding filters will be invoked,  while on 
    level 1 printers the inline decompression code is executed. Rendering
    time on level 2 printers is pretty fast (usually less than 1 minute),
    on level 1 printers the image rendering, of course, is much slower, but
    nevertheless essentially faster than for Run Length Encoded PostScript
    images.


CHANGE OF NAME
==============

Originally xwpick had more short name xpick. First public version of the
utility xpick-1.21 (Rev: 23/11/93) has been uploaded on the asis01.cern.ch
file server at European Organization for Nuclear Research (CERN).

Starting from version 2.10 (Rev: 15.08.94) the name has been changed
to xwpick, to avoid a conflict with xpick by Gerry Tomlinson, which is
"...an X11 Athena Widget implementation of pick, from "The Unix Programming
Environment" by Kernighan and Pike..."


WHERE IT RUNS
=============

Xwpick runs on all UNIX platforms and under OpenVMS (VAX/Alpha).

FILE LIST
=========

Distribution for xwpick-2.20 (Rev: 20/09/94) consists from 18 files:

 1.  0README           This file
 2.  0INSTALL          Installation instruction
 3.  CHANGELOG         Revision history
 4.  CNL_ARTICLE.PS    CERN Computer News Letters article on xpick-1.21.
                       (There is a comparison table with rendering times
                       on different PostScript printers) 

 5.  Imakefile         Input for 'imake' program. 
 6.  Makefile.std      Ordinary Makefile file for 'make' utility

 7.  vmsmake.com       Make file for OpenVMS (VAX/Alpha).
 8.  setup.com         Set up file for OpenVMS.
                     
 9.  xwpick.man        Man page for UNIX.
10.  xwpick.hlp        Help page for VMS.

11.  xwpick.c          Main routine for xwpick.
12.  ImgToolKit.c      Set of routines for work with X Window system.
13.  PS_LZWencode.c    PostScript (LZW) encoding routine.
14.  PSencode.c        PostScript (RLE) encoding routine.
15.  GIFencode.c       GIF encoding routine.
16.  PICTencode.c      PICT (Mac) encoding routine.  
17.  PCXencode.c       PCX (IBM PC) encoding routine.
18.  PPMencode.c       PPM (PBM+) encoding routine.


WARNINGS
========

1) Xwpick uses PostScript level 2 compression algorithm, which
sometimes generates data lines containing symbol % in first position.
That can get confused some PostScript spoolers and post-processing
programs which eliminate PostScrip comment lines (i.e. lines starting
with % in column 1) from the generated output. 

So, be careful by applying such programs for PostScrip files produced
by xwpick.

An example: the dvips program which converts a TeX DVI file to PostScript
must be used with option -K0 in case when the TeX (LaTeX) file contains
references to PostScript files produced by xwpick.

2) Xwpick does not work on 24-bit DirectColor/TrueColor devices.


COPYRIGHT NOTICE
================
Xwpick is Copyright 1993, 1994 by Evgeni Chernyaev

Permission to use, copy, modify, and distribute this software and
its documentation for non-commercial purpose is hereby granted
without fee, provided that the above copyright notice appear in all
copies and that both the copyright notice and this permission
notice appear in supporting documentation.

This software is provided "as is" without express or implied
warranty.


The author may be contacted via:

   Mail: Evgeni Chernyaev
         Institute for High Energy Physics
         142284 Protvino, Moscow region
         Russia
 E-mail: chernaev@mx.ihep.su