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Making the incompatible compatible.

What is the biggest problem I have when preparing a review for Chemputing? I get my hands on lots of interesting software and, of course, it doesn't take too long before it becomes obvious that compatibility is an imaginary goal that can never be achieved. Each set of programmers seems to choose a different format for their graphics output. I'm not the only one who does these columns. When someone else does a review, they seem to encounter a whole new set of graphics formats. I send the files to Ottawa and these go to the typesetter who uses a Macintosh that wants a totally different set of graphics formats. Not only are there a multitude of graphics formats, but each comes in a variety of what we might call "flavours".

As a start, you must recognize that there are two basic types of graphics. Bitmaps are made from a series of dots or "pixels". As an analogy, you can think of a television picture being a bitmap that is scanned to give the image. Vector graphics are a series of lines or circles drawn on the page. The analogy here would be the old drafting board that was used to draw the picture, line by line or circle by circle. Bitmap graphics display or print the entire image as a block; whereas, vector graphics draw the image on an object-lay-object basis. The ultimate resolution of a bitmap image is usually set by the screen or the printer; whereas, the resolution of a vector image is set by the software. It is much easier to make high-quality technical presentations with vector graphics as each individual component can be drawn or edited independently of the next and the image can be very sharp. The entire logic between these two groupings is different and it can be quite difficult to interconvert.

If you want to do conversions and modifications on graphic images, the ideal package is IMSI's HiJaak. Version 4.5 for Windows 95 has just been released. It can read most PC and Macintosh graphics formats and many of the different flavours. If you did nothing else with Hijaak, you can simply load the graphics file in the format you have and don't want and then save it in the format that you do want. It can handle some of the less common formats such HPG/HPGL for Hewlett-Packard plotters and EPS for Encapsulated Postscript, which require special printers and convert them into something any screen or printer can handle.

It will try, but it can't always cope with the idiosyncrasies of the various pieces of software that we may use to produce our final product. Before the figure in Andrei Cornel's, MCIC, ACT! review (ACCN, September 1998, pp. 12-13) left Toronto, I made a high-resolution draft, but somehow the typesetting software lost much of this resolution. On another occasion, the same WMF format went into another publication's typesetting software with no trouble.

If you haven't already set up a way of doing so, Hijaak can also be used to capture a DOS or Windows screen. Be prepared that the file for a simple capture of a 16-bit colour 1024x768 screen takes over 2 MB when saved in the common BMP (Windows Bitmap) format. By converting it into a GIF or JPG/PEG format, the resulting file for that same image can be dropped to less than ten percent of the BMP value, typically 100-200 kB. Chemputing goes to Ottawa as an attachment to an e-mail and then makes its way to the typesetter's Mac. Every step it takes and every platform it crosses provides an opportunity for an error. I decided that the simplest route was to use Hijaak to convert the BMP graphics into the more compact formats and send them as JPGs. Sure, you can compress the BMP file into something much smaller with PKZIP or WinZip, but it turns out that not everyone at the other end knows how to UNZIP files.

Hijaak does a lot more than change file formats. It also provides a fairly complete set of tools to manipulate the graphics. Is the image too light or too dark? Is the contrast too high or low? Do you want to change a red to a blue or a purple to a green? These are some fairly obvious needs that are accomplished with simplicity. How about the difficult ones? The role of a scanner is to convert a hard copy into a bitmap image. The software with mine can then send it directly to HiJaak where I can modify that image as required. As well as the changes I just mentioned, I can crop it to get rid of excess white space or to select a particular region, rotate it to correct for the master not being perfectly aligned in the scanner or change its size to meet file size limitations, e.g., reduce its size for e-mailing. It is that last change that presents the greatest problems. A scanned page eau be a large file that needs several MB and won't fit on a floppy. You can reduce the size by reducing the number of pixels, but as you start to do so, you are of course losing some of the image, e.g., if a line is 2 pixels wide and you reduce the image from 1000x400 pixels to 250x100, your line is now half a pixel wide. You can't have half pixels. You either have one or you don't. Hijaak has a few tricks up its sleeve to keep that line alive.

I recently purchased Perly's CD-ROM map of the Greater Toronto Area, If I save a single map page in colour, those 256 colours produce a BMP file that is more than 6 MB in size. That's a bit too much to e-mail. As the colours aren't too important, I tried saving it in black and white and found the file was exactly the same size. It appears that all the Perly's programmers did was switch from 256 colours to 256 shades of grey. One command and HiJaak converted that image into a true black and white BMP that needed only 200-300 kB. (Please note that I do not recommend this map package. I expected something better, but this is nothing more than a series of scanned images from the individual pages from the paper version, complete with all its many mistakes. Some of the streets near here are in the wrong place and some of the streets it shows as through are "lollipops". Worst of all, I have yet to find a hospital that is supposed to be less than two blocks away.)

Most figures on the Web are in GIF or JPG format. Someone had recently launched their Web page and asked me for my comments. I thought the figures were too dark and the collection of figures just took too long to download. Rather than complain, I sent them one of their figures after giving Hijaak a chance to fix it up. First, I lightened it up a bit and adjusted the contrast. I then reduced the number of pixels. Instead of a dark 200 kB file, they got back a 40-50 kB file with a brighter image.

Many graphics utilities can convert a vector image into a bitmap. This is essentially what happens when you scan an object with a scanner, fax or television camera. It's a much more complex process to go the other way and few utilities tackle this conversion. Hijaak is able to "trace", i.e., to convert a bitmap image into a vector graphics image. The term "trace" essentially describes how it does the job. My first thought was the capability of taking a graph that was faxed to me and creating a beautiful sharp image. It will do so with simpler graphs, but don't try a log-log plot with grid lines. We will be reviewing a package that is designed to do that specific job in an upcoming issue. As graphics needs vary so much from person to person, some people will find this tracing feature to be very useful; others will find it a waste of time.

Several years ago, I made a big copy of my signature and sent it from my fax machine to my fax modem. I was able to use this bitmap signature on documents I sent out with WordPerfect and my fax modem. Trace was able to take my scanned signature and convert it to a line drawing. Isn't that exactly what a signature is? I've had varying degrees of success rising this trace feature with a variety of bitmaps taken from the Web or from my scanner. These have included a variety of drawings of laboratory apparatus. On one occasion, I was even able to trace a CIC logo. Tracing works best with simple line diagrams, but can do some very unusual things when the drawing includes cross hatching, shading or other solid features, e.g., with pictures of people.

Why would you want to convert a bitmap image into a vector image? Most graphics programs used for technical illustration or drafting are vector graphics. If you bring in a scanned image, you are bringing in a graphics block that can be moved, resized or rotated, but not edited or modified with respect to details. If that image was a picture of a beaker or a buret, you could not change the number of graduations nor the numbers printed on them. If you had diagrams of two separate pieces of equipment, you could not take features from both and combine them into a single diagram of a new piece of equipment. If the diagrams are converted into vector format, you can then edit individual features and do this task quite easily.

This is one of those programs that does its job well, while wasting little time. It's simple to load and the learning curve is quite short. Once you get using it, you will find that it is loaded with features that few other graphics conversion utilities possess. In order to use them, you will need a small vocabulary of new graphics terms. I like the fact that almost everything you try can he done in a variety of ways, at least one of which is most suited that particular graphics application. Over the time I've come to the conclusion that if it can be done, Hijaak will find a way. I have only one negative. There are a lot of options that you can try. There is an undo command that takes you back if the that last change didn't do what you wanted. The command is on the edit menu. I would rather have a separate button. This would speed things up a bit when you are trying to see the effects of several options, but that's just nit picking. One word of caution: never discuss this program anywhere near an airplane or an airport.
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Title Annotation:HiJaak Pro 4.5
Author:Silbert, Marvin D.
Publication:Canadian Chemical News
Geographic Code:1CANA
Date:Feb 1, 1999
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