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ZeoSync Makes Claim of Compression Breakthrough
dsb42 writes: "Reuters is reporting that ZeoSync has announced a breakthrough in data compression that allows for 100:1 lossless compression of random data. If this is true, our bandwidth problems just got a lot smaller (or our streaming video just became a lot clearer)..." This story has been submitted many times due to the astounding claims - Zeosync explicitly claims that they've superseded Claude Shannon's work. The "technical description" from their website is less than impressive. I think the odds of this being true are slim to none, but here you go, math majors and EE's - something to liven up your drab dull existence today. Update: 01/08 13:18 GMT by M : I should include a link to their press release.
OK,
- B
http://www.bradheintz.com/
- updated
Pure random data is imposible to compress - If You compress 1Mb of random data (propper Random Data, not pseudo random).. and you get, say 100K's worth of compressed output; what's stopping you feading this 100K's worth back through the algorhythm, again and reduceing it down even more.... again, and again, untill the whole 1MB is squashed into a byte! (Which, obviously is a load of rubbish).....
That's not right. A 1:1 average for a large sample of random data is the best you can ever do. On a case by case basis, you can get lucky and do better, but no algorithm can compress arbitrary random data at better than 1:1 in the long run.
ZeoSync is not claiming to reduce random data 100-to-1. They are claiming to reduce "practically random" data 100-to-1, and Reuters appears to have misreported it. What "practically random" data should mean is data randomly selected from that used in practice. What ZeoSync may mean by "practically random" is data randomly selected from that used in their intended applications. So their press release is not mathematically impossible; it just means they've found a good way to remove more information redundancy in some data.
The proof that 100-to-1 compression of random data is impossible is so simple as to be trivial: There are 2^N files of length N bits. There are 2^(N/100) files of length N/100 bits. Clearly not all 2^N files can be compressed to length N/100.
You can dl the source and look at the algorithms yourself.
lzip. Or just read this snippet from their faq:
1. What is lzip?
Lzip is the most advanced file compression utility ever conceived. It is literally years ahead of gzip (though admittedly gzip was around first), and makes use of mathematical transforms the bzip developers have never even heard of. The practical upshot of this is that when you use lzip, you get the best compression on the planet. Smaller file sizes; faster compression/uncompression times.
Used properly, lzip is capable of reducing a file down to 0% of its original size. Yes, you read that correctly: 0% of its original size. And regardless of file size, this can be done in constant time. Now do you see why some people are calling lzip the "holy grail" of file utilities?
2. What makes lzip different from gzip/bzip2?
Well, other than the performance benefits mentioned above, the real difference is that lzip uses a "lossy" compression scheme. Most other file compression utilities use a "lossless" compression scheme, mostly because the lossless algorithms are better understood and simpler mathematically (most programmers take shortcuts, particularly in areas that involve a lot of math).
This has two side effects. The first is that files compressed with lzip cannot be restored to their original state -- this is the "lossy" in lossy compression. The second is that the performance is vastly improved. Why don't go go back up to question number one and read that second paragraph again. We're talking about a constant-time algorithm that can reduce a file down to 0% of its original size. What's not to like?
Software Wars
Ok, so with current knowledge this all seems total B.S..but remember things always seem impossible until you understand how, imagine trying to explain todays society and its advances to someone from 200 years ago?? Not saying this is all true, just saying dont also discount it straight away because =You= dont know how its done/can be done. Obviously lack of proof makes a person less inclined to think its possible along with current understanding, but Maybe?!
Laptop Reviews
Dead on.... said it before i could