3 ms·
Can we compress random data
- gus_massa 12y agoThis can be easily rebutted by the counting argument: http://www.faqs.org/faqs/compression-faq/part1/section-8.html http://www.faqs.org/faqs/compression-faq/part1/section-8.htm...
- TheAuditor 12y agoThere is a minimum size required size for the file (cant be compressed beyond a few bytes - even if repeatedly applied) and the argument is only valid when we assume the files can be compressed to zero bytes. no claim is made to the effect saying "Can be compressed indefinitely" As I have told, the efficiency of it being able to compress over and over and over again may have chance for data corruption unless better checks and methods are added. (which will again increase the minimum required file size. but you can still compress it)
- gus_massa 12y agoJust for simplicity: Let's assume that I have a file of 1073741825 bytes = 1GiB+1B. And I want to put it inside my exactly 1073741824 bytes = 1GiB pendrive. (Just assume that the OS filesystem doesn't waste any space.) Are you sure that this algorithm will compress my 1073741825 bytes file to a 1073741824 bytes or less file?
- TheAuditor 12y agoYes. That is the only claim I have made. You can replace the first three bytes with two bytes using this method.
- DaveK23 12y agoI've come up with a better compression scheme than yours. My scheme is exactly the same as yours, but you replace the first three bytes with one byte instead of two. Doesn't matter what byte you replace them with, because - just like your scheme - you can't get the original data back by decompressing it anyway.
- TheAuditor 12y agoyou can get the data back. do read the article and paper published.
- TheAuditor 12y agoFor simplicity lets assume the first three bytes are. 102 075 & 179 Now I am making few assumptions for a practical implementation of the technique. PAT() = Units place of sum of all digits. (no claims made,just for an example) Now I can replace the three bytes with the following values 033 and 036 I have also specially stated the challenges of retrieving this information as as of not there are no built in integrity checks.
- DaveK23 12y agoProbably, but it also corrupts your data and won't be able to uncompress it.
- TheAuditor 12y agoPlease note that data integrity checks will need additional data in the file. Hence it can never take the file to infinitely small proportions.
- DaveK23 12y agoThe answer turns out to be 'no'. There, saved you a click.