BlimixWare presents:
The (until now) impossibly perfect lossless compression utility!

Download now:

What is JoeZip?
I take it the tagline didn't clue you in, then. JoeZip is a file compression utility. It is unique in that it is designed to be used repeatedly on its own compressed files, which will keep getting smaller as JoeZip is invoked. The files are fully recoverable, with no loss of data! Just decompress any file as many times as you compressed it, and it will all be there, intact!
Isn't that theoretically impossible?
This has always been thought to be the case. "Surely," reasoned the cynics1, "a perfect compression utility would, if run enough times upon the same file, compress it to zero bytes, at which point all of its data would be lost. There would be no way to restore multiple unique files from a file of length zero." JoeZip proves them all wrong. It can and does restore files perfectly, even from zero bytes!
How does it work?
The algorithm is shockingly simple. Imagine that all possible files are put in order, starting counting at 0, because that's what computer science people do. I'll depict byte values as paired hexadecimal digits, as seen in hex editors.
The zero-byte file is file number 0. File number 1 consists of one byte, of value 00. File 2 is just the byte 01. File 3 is one byte: 02. Keep going through the 256th file, containing the value FF. The 257th file is two bytes: 00 00. Then 01 00. Then 02 00. Incrementing the file FF FF brings us to the 65793rd file: 00 00 00. And so on.
What JoeZip does is to change a file into the next one in order: Down if it's "compressing" the file, and up if it's "decompressing" the file. So if you start with the 75000th file (F7 23 00) and "compress" it once, you get the 74999th file (F6 23 00). "Compress" it 74999 more times, and you get the 0th file; it's fully compressed. To recover your file, you have to remember that you compressed it 75000 times, and decompress it the same number of times, in order to cycle through all the possible files until it gets to the the 75000th file, your original.
If I run JoeZip until my file is zero bytes, where is the data?
That's the beauty of it. It's not taking up any space on your hard drive or other media. Rather, it is fully encoded into the number of times that you have compressed your file. This number exists only in your memory. You can write it down, if you don't trust yourself to remember it, or just make a little tick mark for every time you compress your file.
How long will it take?
Since JoeZip adheres to a strict ordering system, the number of necessary iterations of the program is easily calculable. Assuming that you want to compress your file as much as possible (who wouldn't?), the number of steps equals the base-256 number represented by your file (backward - the first byte is the units byte), since it counts from that down to zero first, plus the number of possible files smaller than your file, since it passes through all of those on the way down. The latter number equals the summation of 256n, where n goes from zero (representing the zero-byte file) to one less than the length (in bytes) of your file (representing all possible files one byte shorter than yours). Conveniently, this summation, when written in base 256, is just a series of ones as long as your file. What this means is that you can add one to every byte in your file, carrying to the right when you have to, and presto! You'll know in advance both the number of times you'll have to compress your file to get it down to zero bytes, and the number of times you'll have to decompress the zero-byte file to get your original file back.
For example, let's say that you're an accountant, and wish to compress a file containing the text "$32.54" followed by a carriage-return and line-feed. The ASCII values of your file look like this:
36 51 50 46 53 52 13 10 in decimal, or:
24 33 32 2E 35 34 0D 0A in hexadecimal.
To see how many times you'll need to compress your file, we first add one to each byte:
37 52 51 57 52 53 14 11 in decimal, or:
25 34 33 2F 36 35 0E 0B in hexadecimal.
Then we treat each byte as a digit in a backward base-256 number, convert to base ten, and get our final result:
"Out of range." Um, give me a moment here...
Somewhat over seven hundred ninety-six quadrillion runs of JoeZip are necessary in this case. (That's "seven hundred ninety-six thousand billion" for non-Americans.) In particular, the number is 796,632,682,505,384,997. You must remember it exactly, or you won't be able to get your file back. If your fingers get tired, or you get hungry, you may want to write a batch file or Perl script to automate the process.
Is JoeZip difficult to use?
One might argue that counting to and remembering the number 796,632,682,505,384,997 is harder than just memorizing "$32.54" and deleting the file. But hey, that's the user's problem. Not mine.
How much does it cost?
JoeZip is absolutely free!
What platforms does JoeZip support?
Currently, JoeZip is only known to run under MS-DOS 5.0 or higher, and Micro$oft Windows 9x. Those of you who instead run a cool, non-M$ OS can thank me now.
Where can I get JoeZip?
You can download JoeZip.exe at the top of this page, or from its link within this very sentence! (But you really shouldn't be downloading and running any strange executables unless you have reason to trust the site in question. You can trust my site, of course. Everybody can trust my site.)
What other great software can I expect from BlimixWare?
Look for JoeCrypt, the cryptography program that stores your encrypted file inside its own password, coming soon!


1. My friend Marty, actually.

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