Hi There! Checked out the other 2 patents on RLE; As a result of this nomarch can be included in main, and the other packages (SDL, OpenGL and Mesa) where RLE are used can stay where they are. After sitting down and carefully looking at them for most of the day, the summary is as follows: US pat 4,586,027 does not apply to nomarch or RLE as below. US pat.4,872,009 has preanalysis and dictionary techniques in it, as well as being bidirectional. Basic RLE and algorithm in nomarch is not like this. US pat. 4,988,998 is about RLE being used and mixed in with LZW... not applicable to nomarch or ordinary RLE... The compression FAQ referenced below is wrong about ordinary RLE being patented. in the above patents as they are either quite specific in their application where RLE is combined with the patented methods as a minor part of the method and not isolated as a stand alone item or claim (4,586,027 4,988,998), or they are about compression methods that are significantly different to ordinary RLE by the use of pre-analysis and data dictionaries (4,872,009). Where ordinary RLE is in a patent it appears that it is used as a common well known technique and by itself would not be held as patentable. I am not a lawyer, but I am trained as a Mechanical Engineer so I do have some skill in reading these sort of documents. If there is any one here with a knowledge of patents could they please check my findings, and get back to me if they can find fault with my reasoning. I hope that this has cleared this up. Best regards, Matthew Grant On Fri, 2002-05-17 at 16:06, Matthew Grant wrote: HOLD! Don't do ANYTHING, Don't worry! Currently investigating nomarch and patent 4,586,027 applies to hardware RLE compression system for tape drives, even though the claims section does not mention this, most of the claims are specific to a logic assembly to implement algorithm where uncompressed sections have preceding and trailing length counts, and compressed sections are datum followed by count (basic RLE). There is also a threshold repeat value built in to. From looking at it, the patent stands because of the other features combined with basic RLE, and does not cover basic RLE by itself. Conlusion: US Patent 4,586,027 does not apply to nomarch, which RLE's by identifying a repeat count of preceding byte with an escape code of 0x90, and the escape code in the input is represented by specially encoding a repeat count of zero. Going to look at US patents 4,872,009, and 4,988,998 (RLE followed by LZ77). On Fri, 2002-05-17 at 13:19, Daniel Burrows wrote: On Fri, May 17, 2002 at 11:58:28AM +1200, Matthew Grant <grantma@debian.org> was heard to say: > Could you please withdraw the nomarch package from the main upload queue. > This thing belongs in non-free. If it violates a patent, shouldn't it be removed entirely? > Sorry about this. I have tried to be careful. Who would have thought that > such an obvious compression technique (Run Length Encoding - count number > of bytes in a row of same value, store count and byte value) is covered by > a software patent? Hm, don't SDL and OpenGL...errr, I mean, Mesa...both use RLE compression to accelerate some blits? Should we remove them too? I have to say that this patent is pretty despicable, even for a software patent. For people who didn't bother following the URL: "The first one covers run length encoding in its most primitive form: a length byte followed by the repeated byte." Daniel, who thinks he "invented" that one sometime in junior high -- /-------------------- Daniel Burrows <dburrows@debian.org> -------------------\ | The Turtle Moves! | \------- Listener-supported public radio -- NPR -- http://www.npr.org --------/ -- =============================================================================== Matthew Grant /\ ^/\^ grantma@anathoth.gen.nz /~~~~\ A Linux Network Guy /~~\^/~~\_/~~~~~\_______/~~~~~~~~~~\____/******\ =============================================================================== -- =============================================================================== Matthew Grant /\ ^/\^ grantma@anathoth.gen.nz /~~~~\ A Linux Network Guy /~~\^/~~\_/~~~~~\_______/~~~~~~~~~~\____/******\ ===============================================================================
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