Img Software Set Version 1.3 June 15, 1990 Paul Raveling (Raveling@isi.edu) USC Information Sciences Institute 4676 Admiralty Way Marina del Rey, Cal. 90292 (213) 822-1511 This is a set of software for use of images in an X11R4 environment. Images can range from digitized color photographs to simple monochrome copies of X windows. A matching collection of several hundred image files in Img format is available by anonymous FTP from venera.isi.edu, [~ftp/] images. See img_files.spec For information on the Img file format. This is a plain text file in this directory. The Img Software Set includes the following components: ./imglib Library of "Img" routines: A "toolbox" of routines to support image-using applications. See ./imglib/README for additional information. ./imgprogs Simple programs built over imglib routines: descimg Describe image file dispimg Display image file excolors Examine named colors exhibit Exhibit an image collection giftoimg Convert GIF file to Img file mapimg Map or remap an image primg Print window, screen, or image file savewin Save window image in file setback Set background to image The following directories were supplied on the X11R4 release tapes but are omitted in new releases of code: ./color_mapped \ Directories corresponding to image file ./color_rgb \ subdirectories on venera.isi.edu; ./grayscale / Each contains a README file and a single ./monochrome / sample image. CAUTION: Some operations on require LOTS of memory for large images. It's possible for Various functions to abort with an "insufficient memory" message, especially when using high-resolution RGB (24-bit-per-pixel) images. ------------- Changes in Version 1.3: 1. A few bug fixes. Two of the bugs could produce crashes in color quantization; one involved a race condition when displaying an image in an X11 window. One other bug was capable of crashing giftoimg. 2. Color quantization now includes dithering. This complements the new quantization algorithm and produces MUCH better images quality in the cases we've checked so far. ------------- Changes in Version 1.2: 1. New color quantization algorithm is supplied in imglib; module quantize replaces both quantrgb and quantcmi. The new algorithm runs much faster than the old algorithm and visibly improves image fidelity in most test cases which have been checked to date. Fidelity should improve further when V1.3 adds dithering, especially when quantizing to a very small number of colors. 2. A few minor bugs have been fixed. Lots of other minor bugs remain to be fixed. ------------- Changes in Version 1.1: 1. New client programs: excolors, giftoimg, exhibit 2. Improved generality: Virtually all imglib routines and Img clients now handle either color-mapped or RGB images with equal aplomb, if not equal speed. 3. Support for additional X11 visual types, with emphasis on 24-bit DirectColor. Also in this category is automatic dithering for monochrome visuals. 4. Imglib accepts several display-related options as either command line arguments or X (resource) defaults. In general these apply to all Img client programs. What didn't make it in time was an improved color quantization algorithm and matching color dithering. ------------- To build the Img Software Set: Build procedures are consistent with X11 standards, using Imakefiles to direct construction of Makefiles. If the X Consortium supplies a "make World" for contributed software in X11R4, this will build the Img Software Set. To build it manually, connect to the Img top-level directory and use imake to make the first Makefile. This is usually done with a shell script invocation something like ximake $TOP After that, while connected to the same directory, run: make Makefiles make depend make all After testing, make install make install.man ** Caution: Installation is heavily system-dependent, and often is site-dependent, especially for manual entries. We recommend first checking a sample client program by... cd imgprogs/dispimg make -n install make -n install.man If all is well you can repeat without the -n flag; at worst you can redirect make's output to a file and edit it into a more appropriate shell script. ------------- Finally, the following copyright notice applies to the Img Software Set: Copyright (c) 1989, 1990 University of Southern California Paul Raveling USC Information Sciences Institute 4676 Admiralty Way Marina del Rey, California 90292 The authors grant without fee permission to use, copy, modify, distribute, and sell this software for any purpose, provided: -- The above copyright notice appears in all copies. -- This disclaimer appears in all source code copies. -- The names of ISI and USC are not used in advertising or publicity pertaining to distribution of the software without prior specific written permission from ISI. ISI provides this software freely as a public service. It is NOT a commercial product, and therefore is not subject to an an implied warranty of merchantability or fitness for a particular purpose. ISI provides it as is, without warranty. This software is furnished only on the basis that any party who receives it indemnifies and holds harmless the original authors and their sponsors against any claims, demands, or liabilities connected with using it, furnishing it to others, or providing it to a third party. The author of this software is Paul Raveling. Development used the author's after-work hours and ISI's facilities. Thanks are due to ISI for allowing such extracurricular work and to Hewlett Packard, whose University Grants program provided the 9000/370 workstation and supporting software which was the platform for this work.