Friday, September 30, 2005

Geiger random bits

Given a stream of random integers with unknown distribution (representing time spacing between clicks of a Geiger counter), how would one generate a stream of random bits from it?

A simple method is to compress the stream, then hash chunks of sufficiently large compressed output. It requires some prayer that the compression picked up the distribution peculiarities, and that the hash function is good enough.

An even simpler method is just to substitute, or pre-augment, compression with the least significant bit of each integer.

No comments :