This document is the manual associated with my tutorial on imaging programming presented at the Australian Unix User's Group 2002 Winter Conference in Melbourne Australia. It is intended to serve as the basis for discussions during this day long tutorial, as well as being a reference for the attendees once they return to their every day lives. Please note that all the information in this tutorial is copyright, as described elsewhere in this document. Michael has been working in the image processing field for several years, including a couple of years managing and developing large image databases for an Australian government department. He currently works for TOWER Software, who manufacture a world leading EDMS and Records Management package named TRIM. Michael is also the developer of Panda, an open source PDF generation API, as well as being the maintainer of the comp.text.pdf USENET frequently asked questions document. You can contact Michael at mikal@stillhq.com. Michael also has a whole bunch of code (most of which relates to imaging) at his website: http://www.stillhq.com This tutorial started life as a series of articles about the TIFF image format, which were published by IBM DeveloperWorks (http://www.ibm.com/developerworks) in April and June 2002. This logically grew into the tutorial you see before you today. This tutorial is based on my several years experience as an imaging developer, and the common mistakes that people seem to make over and over. Perhaps this tutorial will go some way to correcting some common misconceptions. There are some things which I assume you know, and which are outside the scope of this tutorial. This tutorial discusses code. Almost all of the code discussed is written in C. It is therefore safe to assume that if you don't have a good working knowledge of C, then you're likely to get a lot less out of this tutorial as those who do know some C. On the other hand, don't worry about the more esoteric syntax, I'll explain this as we need it. It should also be noted that the code samples in this tutorial are not optimal. They have been written to be as readable as possible, and not necessarily the most efficient possible. Please bear this in mind before blindly copying them. It is outside the scope of this document to teach you how to compile and link source code into an executable form on your chosen architecture and operating system. You will need to understand this before you will be able to use any of the code in this document. For those of you using gcc on a unix (or unix-like) operating system, then the following points might be all you need to know. If you need more information, then a http://www.google.com search will serve you well. Libraries are added to the link command using the -l command line option. For instance, to compile and link the source file foo, with the tiff library, you would use a command line along the lines of gcc foo.c -o foo -ltiff -lm. You need to include -lm almost always. When you compile a c program using gcc without specifying any libraries, you get a -lm for free. As soon as you start specifying any libraries (for instance in this case -ltiff), then you also need to explicitly specify the math library as well. You will almost certainly also need to add the library and include paths for the installed version of the relevant library to the compile command line as well. Directories are added to the library search path using the -L command line option. Include directories are added with the -I option. The make files included with the samples in this tutorial a probably a bad place to look for introductory compile examples, as they use automake and autoconf to try to detect where the various required libraries are installed... There are many people who need to be thanked when one attempts a project of this size. I would specifically like to thank my wife and son, who put up with me being geeky so very often.

I should also thank the following people: Doug Jackson (doug_jackson@citadel.com.au), for proof reading and getting me interested in this whole topic to start with Tony Green (greeno@bandcamp.tv), for occasional DocBook wrangling Michael Smith (smith@xml-doc.org), for DocBook hints This tutorial was written in DocBook SGML using xemacs. This was then converted into PDF using the jade SGML tools. Diagrams were developed in a combination of the gimp, Adobe Illustrator, and custom developed code. Diagrams were converted to EPS as required by jade using ImageMagick. A series of DocBook generation scripts was also used to automate some of the generation of this document. These scripts can be found in my online CVS repository at: http://www.stillhq.com/cgi-bin/cvsweb/docbooktools/ The source for this tutorial is available at: http://www.stillhq.com/cgi-bin/cvsweb/tutorial-imaging/ This document is covered by two licenses -- the license for the text of this document, and the license for the included source code. The license terms are set out below. This tutorial is Copyright (c) Michael Still 2002, and is released under the terms of the GNU OPL. Distribution of substantively modified versions of this document is prohibited without the explicit permission of the copyright holder. Distribution of the work or derivative of the work in any standard (paper) book form is prohibited unless prior permission is obtained from the copyright holder. 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You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Also add information on how to contact you by electronic and paper mail. If the program is interactive, make it output a short notice like this when it starts in an interactive mode: Gnomovision version 69, Copyright (C) 19yy name of author Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details. The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than `show w' and `show c'; they could even be mouse-clicks or menu items--whatever suits your program. You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if necessary. Here is a sample; alter the names: Yoyodyne, Inc., hereby disclaims all copyright interest in the program `Gnomovision' (which makes passes at compilers) written by James Hacker. <signature of Ty Coon>, 1 April 1989 Ty Coon, President of Vice This General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Library General Public License instead of this License. Copyright (c) 1988-1997 Sam Leffler Copyright (c) 1991-1997 Silicon Graphics, Inc. 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