in reply to Re^2: URL string compression?
in thread URL string compression?

As you've seen, with 64 characters in the input, that 90*6-bits = 67.5 (mostly unacceptable) 8-bit chars as your best "simple transform' compression. A bare 2/3rds compression, even if all the 8-bit chars were acceptable in a filename which the aren't.

Your best hope is if your filenames can be split into various fields that can be represented by a number that is shorter than the fields text representation. For example: if one component of the name was one of 'North', 'NorthEast', 'East', 'SouthEast', 'South', 'SouthWest', 'West', 'NorthWest', that same field could be replaced by a digit 0-7, or maybe just 4-bits in conjunction with some other field with upto 3-bits.

Without seeing examples of the filenames, and the range of values the fields within represent, it's hard to be more helpful.

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Edit: g0n - reparented at authors request

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