On Tue, 23 Jul 2002, Jinx wrote:

>> Maybe a little late...
>>
>> Remember the good old check of PRNG output entrophy. If you
>> gather a fair value of randomness, try to compress it with common
>> utilities, e.g.gzip. The higher the entrophy, i.e. "randomness", the
>> less compressable the data is. Of course, the quality of the
>> compression algorithm is a factor but today's best compression
>> utilities should be fairly good at detecting any kind of pattern or
>> non-randomness
>
>I've got just a basic knowledge of compressors, but not modern
>ones. So you're saying a file made of supposedly random numbers
>probably shouldn't decrease in size ? At all, or maybe just a little ?
>The algorithms I used to write for compression would actually
>make a file bigger the more disparate the data, and really were
>suitable for repetitive or regular data like black & white line drawings

If you try to compress a file with too much entropy the file *grows* (by
the size of the compression headers at least).

Peter

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