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Finite State Entropy - A new breed of entropy coder

fastcompression.blogspot.fr

1–10 of 14 posts

Re: Finite State Entropy - A new breed of entropy coder

#2
Well, this is interesting.

I toyed around with entropy encoding at one point based on a republished copy of an old Dr. Dobbs' Journal article I found, and I managed to cleanly reimplement the described algorithm in Python and reproduce the example mentioned in the article... but eventually I hit a problem I wasn't smart enough to debug. I'm eager to see whether this new algorithm is more approachable.

Re: Finite State Entropy - A new breed of entropy coder

#4
"In a nutshell, this coder provides the same level of performance as Arithmetic coder, but only requires additions, masks, and shifts."

Didn't IBM's Q-Coder also make the same claims?

Here's another one: http://www.gvu.gatech.edu/people/official/jarek/courses/7491...

Re: Finite State Entropy - A new breed of entropy coder

#5
This was a nice article.

In the comments Jarek Duda discusses some of the more technical details of the implementation and of his ANS paper that enabled this writeup. One cool thing I noticed is this:

    Another advantage of ANS is that we can slightly perturb     
    the initialization procedure using a pseudo-random number 
    generator initialized with cryptographic key (e.g. and 
    also the number of block): for example choosing between 
    the lowest weight symbol and the second best one.
    This way we get simultaneously a decent encryption for free.
Does anyone know what modern compression tools use for entropy coding? Do they all use huffman and would this help them increase speed? What about gzip for HTTP transactions?

Re: Finite State Entropy - A new breed of entropy coder

#6

"In a nutshell, this coder provides the same level of performance as Arithmetic coder, but only requires additions, masks, and shifts." Didn't IBM's Q-Coder also make the same claims? Here's another one: http://www.gvu.gatech.edu/people/official/jarek/courses/7491...

The Howard-Vitter coder only works for binary alphabet (0/1).

Re: Finite State Entropy - A new breed of entropy coder

#7

"In a nutshell, this coder provides the same level of performance as Arithmetic coder, but only requires additions, masks, and shifts." Didn't IBM's Q-Coder also make the same claims? Here's another one: http://www.gvu.gatech.edu/people/official/jarek/courses/7491...

Same of Q-Coder :

"The Q-Coder is a new form of adaptive binary arithmetic coding"

Re: Finite State Entropy - A new breed of entropy coder

#10

How does it compare to the algorithm used in FLAC or mpeg4 lossless? Is there a reasonable way to benchmark the differences? https://en.wikipedia.org/wiki/Golomb_coding#Simple_algorithm

Golomb is way too static, it doesn't compress as well as Huffman, let alone FSE.
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