Converting a DOS intro to JavaScript/HTML5

One day I had the idea of converting my fr29b DOS intro to JavaScript. Using the canvas element of HTML5, this should be an easy task and offer a good performance as well. To make the port as similar as possible, the standard VGA DOS palette should be supported. Drawing the ARGB values into the canvas can be speed up […]

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Analysis of the 624 (Six-2-Four) packer

The 624 packer is a executable packer that got released in 1997 by Kim Holviala. It only supports DOS .com files and was targeted to compress 4kb demoscene intros but offers a decent compression of files from 1 kb to 20 kb size. Uses LZSS (Lempel–Ziv–Storer–Szymanski) compression algorithm The assembly unpacking stub is 127 byte small Fixed length huffmann codes […]

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Unpack packed DOS binaries with DOSBox debugger

Set up the DOSBox debugger First off, you will need a DOSBox version that is compiled with the built-in debugger. If you are using Windows and don’t want to compile it yourself, you can grab the latest version of the DOSBox debugger from http://www.vogons.org/viewtopic.php?t=7323. The unpacking target of my choice is Omniscent, one of the most impressive 4kb DOS intros […]

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29 byte DOS intro called fr29b

When going back down memory lane about my programming projects the first memory that comes up is developing software under DOS. The simple way of writing programs as .com files allowed for a lot of fun stuff like coding size competitions. Those executable files did not include any header and got executed as code starting from first byte of the […]

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