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April 1999

View From the End (User)

PMView 2.0 - Addendums

By: Don K. Eitner (secretary@os2voice.org) http://www.tstonramp.com/~freiheit/

Last month in my View From the End (User) article, I reported that PMView 2.0 (beta 7) loaded some images much slower than PMView 1.04 did. In particular, I noted a Windows Bitmap of size 2961x3933 pixels which loaded in 96 seconds in PMView 2.0 but only 19 seconds in PMView 1.04. It turns out I was right in my conclusion that some of this difference was due to new features in version 2. The Bitmap code in particular has been upgraded to handle additional formats from Win32 systems and 15- and 16-bit formats from OS/2. Therefore the loading speed is somewhat reduced due to this additional code. Other graphics file formats should not experience this loading speed difference.

I have performed the tests again, having converted the same image to PNG format (to retain both quality and color depth). I started with a freshly booted system and opened the image into PMView 1.04 from the Drives object. I then rebooted the system and did the same for PMView 2.0 beta 8. I then did both tests in reverse order, again on freshly booted systems each time.

PMView 1.04 slowed down quite a bit compared to my original tests, signifying that PNG decoding is not as efficient as raw bitmap decoding. Both new tests on version 1.04 showed a 50 second load time.

Conversely, PMView 2.0 actually decoded the PNG image faster than it had decoded the BMP! Load time went down from 96 seconds to only 90 seconds. Still slower than PMView 1.04, but this is primarily due to my system's memory. I have only 32 megabytes of RAM and PMView 2.0 uses 2 megabytes more RAM than version 1.04, therefore my system is swapping to the hard drive more in version 2.0. Swapping equals a major slowdown. If your system has 64 or more megabytes of RAM, you will probably never notice a difference between the two.

Also, I was incorrect in stating that the inability to quickly and easily display [+] next to drives upon first opening the File Open Container was due to a developer tool limitation. It is in fact a limitation of the container which is a part of OS/2 itself. Nevertheless, the problem is unlikely to be remedied by anyone other than IBM. The Win32 container does allow the [+] to be applied next to the drive letters without having to scan each drive for subdirectories. However, even when the [+] is displayed automatically, you may not like it -- PMView might then tell you a drive has subdirectories when it does not, and you'll never be sure until you click it.

More New Features

VOICE's first SpeakUp attempt with PMView's author, Peter Nielsen, met with technical problems as internet routers in his part of the world blocked him from connecting to our IRC servers on WEBBnet. During our re-scheduled SpeakUp on March 29, we were given an extra long feast of feature information for the new PMView. Some points of interest include line-by-line display of images while they're being scanned in by CFM TWAIN, that the official release of PMView 2.0 for sale is currently set for May/June, and that PMView 2.0 was written as a completely object-oriented design to allow easier updates "for many years to come". According to Nielsen, "More than 50% of the code was rewritten".

Another nice new feature for people who need to view a large number of images one after another is a read-ahead cache which will speed up loading the previous and next images in the current directory.

Planned Enhancements

PMView 2.0 is by no means the culmination of Nielsen's ideas. He's already looking forward to version 2.1 and/or 3.0. Quoting again from our PMView 2.0 SpeakUp, "Much higher on the priority list is support for vector formats like CDR, MET and WMF." He is also planning to add support for animations (such as GIF89) in a future release.

For those of us running (or planning to run) multiple operating systems, not only will there be the OS/2 and Win32 versions of PMView, but Nielsen is looking to build Linux and BeOS versions after 2.0 goes on the open market.

With the birth of the Linux version of PMView, we are likely to see support not only for CFM and STI TWAIN scanning but also for the free open-source SANE scanning software.

Another feature planned for a future release is support for merging bitmaps while maintaining transparency -- for instance, to take a GIF image of a dog which has a completely transparent background all around the dog and place it into another GIF file. "Transparent" sections are actually of a color, but the GIF file tells any program which supports transparency to not display that color and to let whatever is beneath the GIF show through. Currently, trying to merge a "transparent" image onto another image in PMView will display a rather ugly output file with the "transparency color" showing. In the future this will be changed, according to Nielsen.

PMView (http://www.pmview.com/)
CFM TWAIN (http://www.cfm.de/f_products_start.htm)
STI TWAIN (http://www.stiscan.com)

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