The magazine of the Melbourne PC User Group For the bookshelf

Guide to Computer Viruses
reviewed by Don Gingrich

This is the first book about computer viruses that I can recommend without reservation. Robert Slade is not a computer virus researcher, but is active in the online antivirus community. As a result the ideas and concepts presented have been subjected to the most severe peer scrutiny in the Usenet comp.virus newsgroup. Most other virus information books I have read suffer from moderate to severe lapses in accuracy, or are biased in favour of some antivirus product on the market. The author has the advantage of being independent of the commercial antivirus scene.

There are currently several discussions about the best approach to protection, so any book written on the subject by an antivirus software developer will tend to support and justify his design decisions. An independent view of the debate is essential to understand the issues. Robert Slade does a good job of presenting the relative advantages and disadvantages.

The book has an excellent bibliography with reviews of the cited publications. Robert Slade has built up a well-deserved reputation for his capsule reviews of security and risk-related books and which are available from ftp.cert.sei.cmu.edu.

A companion disk contains antivirus programs and utilities. It suffers from the problem that affects any software of its type: most of the programs are dated. The only reasonable source for time-sensitive material, such as virus scanners and other detectors, is the Internet or a BBS linked to major international networks. Nevertheless, the disk has a good selection of the available alternatives for PC virus protection. They are useful for testing the interface and features, if not for active use as an antivirus protection system.

The E-Mail Companion
reviewed by Major Keary

Inexpensive by computer book standards, the E-Mail Companion is a "guide to the dos, don'ts, and etiquette of using" e-mail. The Internet gets a mention - well, more than a mention - but the main purpose is to explain and promote e-mail as a viable and efficient form of communication.

Network administrators and managers responsible for corporate communications will, if they are not already familiar with e-mail, find this a good introduction. It is not a how-to-connect book, but describes the things you can do, such as sending image files in ASCII, transmitting data and files, and getting files from the Internet.

The E-Mail Companion is for those with a reasonable degree of computer literacy and who want to use e-mail to communicate via the Internet, other global networks (FidoNet, for example), and even LANs. It is by no means superficial, containing useful examples of the form of e-mail messages for various purposes. For example, the use of ftpmail to obtain files. On that topic, be very careful to get the message right. Quite recently someone accidentally set in train the download of a complete (and very large) directory, an unstoppable process that tied up bandwidth while frantic attempts were being made to contact the system administrator.

The reader will find useful information not included in other e-mail titles, such as the relative bandwidth use required by a message sent as a fax and as e-mail. It is also much less expensive than books of similar quality. A copy is available in Melb PC's book library.

Unveiling Windows 95
reviewed by Major Keary

Windows ninety-when? The new stand-alone operating system version of Windows is on the verge of release - so we are told - and there has been a flow of books describing its new features. These are useful for anyone interested in assessing Windows 95 before committing to upgrade, or transferring from another system.

The principal author of Unveiling Windows 95 has good credentials for the task; he has written several books and is part of a consulting firm, Oakleaf Systems, which specialises in Windows database and multimedia applications.

Of special interest to potential users is how Windows 95 will accommodate applications written for Windows 3.1+ - for those wary of vendor assurances there is a detailed description of how 16-bit applications will run in a 32-bit environment. Some users will require access to DOS for some applications and virtual DOS machines are also described.

Specifications for Microsoft (MS) Plug and Play approved applications and hardware are spelled out. MS has a Designed for Microsoft Windows 95 logo that OEMs will be able to display if their products qualify. The file system will change and part of that is provision for long file names.

Part of the book concentrates on multimedia features. The 32-bit system will enable a much higher quality of application, particularly video. Those tiny video images possible under Windows 3.1 will grow to credit card size; to get anything bigger will require an MPEG card. The book does not tell us, but one can guess that some significant memory upgrade will be necessary for high-end video. There is a discussion of how future CDs will be affected by 32-bit systems.

Improved networking and communications facilities, with emphasis on Internet connection, are much publicised features of 95 and are covered in some detail.

The book does not stop at simple descriptions of Windows 95 features, but provides a detailed discussion of how they work. There will be further versions of 32-bit operating systems and Unveiling Windows 95 gives an insight to issues and future directions.

Prentice Hall's Illustrated Dictionary of Computing
reviewed by Major Keary

The second edition of Prentice Hall's Illustrated Dictionary of Computing is notable for its recognition of variations in usage between North America and just about the rest of the world. To my knowledge this is the only reference of its kind to address that situation.

There are many differences in the way writers use terms and abbreviations, whether they (both the writers and the terms) originate in the US or elsewhere. Who can tell what a local journalist means by billion? Some appear to use it in the sense of "a lot of dollars", oblivious of the particular currency and different definitions: in North America a billion is 1,000,000,000, but here (and most other non-American places) it means 1,000,000,000,000. One thousand million may be a billion in the US, but here it is a milliard. The metric prefix giga means one thousand million, and tera means a billion (one million million). Prentice Hall's Dictionary notes such differences, which is important for accurate writing.

It also includes ISO definitions, which are identified as such and should be observed by all writers. The Dictionary provides a convenient way to check whether an ISO definition exists for any given term.

A wealth of current information is written in concise and clear language with numerous illustrations to help the explanations. There is some surprisingly technical information, such as the ISO table of dyadic (N-adic) Boolean operation, but some things one would expect to find are given minimal treatment, such as data compression (the item talks about compression standards in modem transmissions, but barely mentions compression techniques for data storage). However, one cannot reasonably expect absolute coverage; the publishers have done an excellent job in managing to do so much in such a compact space.

An appendix contains a brief guide on correct usage of computer terminology that, in many respects, clashes with received forms. My first reaction was negative, but on reading Jonar Nader's reasoning for Mb, kb, etc. I find them logical and worth promoting.

A valuable reference for writers, students, and teachers. Any serious computer user should have a copy. It is also fun to browse.

Graphics Programming with Visual Basic
reviewed by Tony Stevenson

If you want to learn about graphics programming using Visual Basic (VB) this book is both a comprehensive guide and reference to an often misunderstood area of VB programming. It is not designed to teach the ins and outs of general VB programming; the author assumes readers are at least past the beginner stage. However, as a text on graphics programming it contains enough information to be suitable for all levels of graphics programmers.

I like the book because it presents entire VB programs, with accompanying explanations of the code, as well as comprehensive descriptions of the objects used and their associated property settings. All the source code is supplied on a companion 3.5-inch disk.

The author's attention to detail makes it easier to see how the various programs work as well as the reasons behind why certain program constructs are used.

A programming book is always more valuable (and enjoyable) if the examples are more than just Mickey Mouse ones. The programs here are complete projects that perform useful and interesting tasks. You can incorporate them (or parts of them) into your own VB applications or use them as a basis for projects you are just beginning to develop. Programs introduced early in the book are later reintroduced with improvements that help your knowledge of graphics to grow in an ordered, step-by-step manner.

Some of the topics covered are Bezier curves, text alignment, flood fills, techniques for blending shades of colour, drawing, and animation.

For best results you should be using Visual Basic 3.0 for Windows 3.1 or 3.11 with a SVGA monitor. The sample programs were designed for SVGA configured at 800x600 resolution and 256 colours. It is worth noting that one sample program requires the professional version of VB 3.0 in order to run successfully.

The book is ideal if you enjoy programming (and who doesn't with VB), want to have some fun, and are also looking to improve your knowledge of and experience with both VB programming and graphics.

Hidden Images: Making Random Dot Stereograms
reviewed by Ken Holmes

If you have a yen to produce your own autostereograms, this may be the book for you. It spends much time on the basis of this optical illusion, which depends on the use of a horizontally repeating pattern, using patterns of text, dots or small images. An individual pixel (and thence, surfaces) can be moved away from the background by colouring another pixel, spaced at an appropriate distance, the same colour.

The common technique (excepting my direct approach; see PC Update, Sept 94) is to first produce a "depth" file where each pixel has a colour number or a greyscale value indicative of its distance from the observer. This is transformed into an autostereogram by software; that supplied is POPOUT-LITE, which only works with 16 colours and can thus give 16 contour levels in any picture - sloping surfaces can be rather jagged. The registered version, POPOUT-PRO, and the commercial GP_POPOUT (US$35), can handle 256 colours or greyscale levels. The book doesn't mention it but there is a practical limit to the number of levels actually used, imposed by the screen's horizontal resolution, since matching pixels can only be separated by an integral number of whole pixel spaces; (640 for VGA). A typical image would only use 30 to 40 levels, rising proportionally for SVGA screens.

POPOUT-LITE can handle depth files produced by Windows Paintbrush and some other paint programs and the book describes the tools and procedures for using Paintbrush; incidentally, the software only runs under Windows. How interesting the images are would depend on your ability to put a 3D concept into coloured contour areas. A shareware raytracing program, Polyray (not POV-Ray), can produce depth files of geometric objects easily and with accuracy; this might be more satisfying, particularly with curved surfaces. Depth files are used in several programs and are apparently freely distributed on the BBS net. As a finale, the book suggests that animations could be produced - this would definitely be via the raytracing route, using an animation tool such as DTA to combine the frames.

The book is liberally illustrated with - guess what - autostereograms.

Reprinted from the July 1995 issue of PC Update, the magazine of Melbourne PC User Group, Australia

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