I'm out of my depth with this.

Any compression system involves the concept of entropy, since entropy is a measure of information, and maximising information density or minimising redundancy is what compression is all about.

Can you enlarge on your actual assignment?

Paul
 
I haven't got the assignment yet, that is next week, this week are supposed to be doing background reading on Entropy, I think I need to read a bit of Huffman.

I've not been taught any of this stuff, we ust get a little bit of background reading to each week and this week it is entropy.

One thing is describe the properties of the entropy function, I am guessing logerithims have somthign to with it.
 
Say we had 32 equally likely symbols. The Shannon Entropy function suggests that this requires 'minus one times the sum, where n=0-31, of the probability of the nth symbol times the log2 of the probability of the nth symbol' bits per symbol. Since each symbol is equally likely this resolves to -32*(1/32)*log2(1/32). I think this calculates out at '5' which is convenient.

Paul
 
Aaaaaahhhghhghgghghhhhhh - the flashbacks are starting - the HELL of cybernetics has finally come back to haunt me! Information Theory - I *knew* I'd heard that "entropy" word somewhere before...

Good luck AT - it's not as scary as all that (but I've forgotten all of what I was taught on it!)
 
Huffman? Sounds familiar. Isn't that the one used for fax compression. I seem to remember writing a codec for that once. My boss at the time implemented an LZW codec in assembler in about 2 weeks so it can't be all that hard. Don't panic AT!
 
From Flanders and Swann's song about thermodynamics:
"Heat is work and work's a curse,
And all the heat in the universe,
Is going to cooooool down,
Because it can't increase,
Then there'll be no more work,
And there'll be perfect peace."
"Really?"
"Yeah, that's entropy man."
Click to expand...
 

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