= 27d567bc2d48d9f40e9ccc20ea370b15)
Houshalter comments on Significance of Compression Rate Method - Less Wrong
You are viewing a comment permalink. View the original post to see all comments and the full post content.
= 783df68a0f980790206b9ea87794c5b6)
Loading…= b715d02e85f7b3b4ae65ca3d3e450868)
Subscribe to RSS Feed
Powered by Reddit
= f037147d6e6c911a85753b9abdedda8d)
You are viewing a comment permalink. View the original post to see all comments and the full post content.
Comments (60)
First of all, compression doesn't have to be limited to just commonly occuring sets. For example, if I create a fractal, you don't have to find out commonly used colors or pixels that occur near each other, but just create a program which generates the exact same fractal. When you do this you add another element to the system - time. How much time do you spend trying to compress something, or vice versa, decompressing it? And no compression system can garuntee that every observed instance can be compressed to less then its original size. Infact, there are always going to be cases where compressing it actually increases the size of the file, possibly significantly, but at least just a few bits.
That kind of regularity can still be explained in the language of commonly occurring sets: For a fractal, you reserve a symbol for the overall structure, which is common (in that something like it occurs frequently), and you have a symbol to instantiate it, given a particular position, to what scale. Time is handled similarly.
Compression amounts to saying: "This is the structure of the data. Now, here's the remaining data to full in any uncertainty not resolved by its structure." The structure tells you what long symbols you can substitute with short symbols.
True, compression only attempts to guarantee that, for the function generating the data, you save, on average, by using a certain compression scheme. If the generating function has no regularity, then you won't be able to compress, even on average.
Yes but if you have a symbol for every possible fractal, it defeats the purpose. The point was to use time as a memory resource. This also works in reverse with caching and other methods, you can use memory as if it were time. Both, however, only work up to a point.