Talk:Softdisk Library Format

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Compression and exceptions

I had a quick look at the LZW compression used by SOFTLIB.EXE and I was wondering in which case the exception that is mentioned in the text occured. I was able to write a very quick implementation of an LZW decompressor (with a sliding window of 4 KB) that worked perfectly, so I'd like to test that code for those exceptions. Another thing I noticed is that the LZH compressed data doesn't appear to be based on the compressed data that the LZW compression produces. This seems to be a different compression scheme, using codeword lengths of 8 and 9 bits. --K1n9 Duk3 22:32, 2 January 2012 (GMT)

Seems I was a bit of a twit, I have rewritten the page entirely given my recent pokings at this format. There are no exceptions, just a faulty windows calculator that gave me the wrong binary for a hex value. The 'LZH' I think is just regular LZW, but using a dictionary instead of a sliding window, much like Keen 1's graphics use. --Endian? What are you on about? 05:13, 18 April 2012 (GMT)