Best Compression I have ever seen - How did they do this?

[qualia787]

I discovered something strange when downloading the free MOPY screensaver
from HP. (you can Google it yourself and test it out)

The download file is only 1.30MB (it was originally made to be easily distributed
on FLOPPY (yes Floppy) disks) and uncompressing takes a long time (for such
a small screensaver..) but it unpacks to over 8MB!

Now when I try to COMPRESS the MOPYFISH folder back again with the
compression utilities below I get nothing remotely NEAR the compression
level of the original distribution.

MOPYFISH folder 8.85MB
MOPYFISH.zip - 4381KB
MOPYFISH.rar - 4009KB
MOPYFISH.7z - 3671KB


How is it possible they packed the whole thing in only 1.30MB? Is this a
special tool they wrote specifically for the program and if so why can't
we use such an algorithm to pack all programs might tighter??

Seriously test it out yourself.

Download the screensaver at *www.mopyfish.net/
Get winzip at *www.winzip.com/prod_down.htmWinrar at *www.rarlab.com/7-zip at *www.7-zip.org/
Whatever you no you will NOT be able to get that 8.5mb program back into the 1.30mb that it came out from!!!!


I'd like to know WHY is this? So is it possible for me to write a program that is 80MB and pack it into only 10MB?

 

[Ecko]

There are many good compressors like Uharc
Just forgot the best one (Uharc isnt)

 

[CadCrazy]

Best one is 7zip i think.

 

[uzair]

KGB Archiver rulez!

I remember my friend compressing GTA san andreas setup(about 3 GB)
to a mere 64 KB...

Yes 64 kilobytes not 64 mb

The only thing bad about kgb is it's very slow and demands 2 GB+ of RAM for such high compression...

 

[victor_rambo]

I remember that some time back there was a fake vista package compressed upto 1.4 MB. When this 1.4 MB archive was extracted, its size was 700 MB!

I think this is possible with KGB archiver, but you will need A LOT of resources such as for that! You can do that on a ordinary 25K assembled PC.

 

[ray|raven]

^Actually , No.
There was a thread on this before ,
See this:*www.thinkdigit.com/forum/showthread.php?p=306976

Quoting FatBeing from it,

Well if no one's going to try the WinRAR trick, I guess I shall have to reveal All.

The file is not Vista, not even a pre-release build. It's a meticulously crafted collection of files that really have no content apart from the same character repeated several times - open any of them in notepad and you'll see.

Compression works on a simple funda - find patterns, and then store the number of times it's repeated. So compressing a text file with, say, "Digit" written a hundred thousand times will create a text file that is most likely 50 odd MB, but when I compress it, it will be a KB at best - the compression algorithm will just read the content as "Digit * 100000", which obviously takes up little or no space.

And guess what? Every single file in this iso is like this.

WinRAR, incidentally, compressed the iso to 1.2 MB.

Finally, tech_mastermind: I hope you got your answer now. Someone could rename the goatse image to "Vista.iso", but that doesn't make it Vista now, does it? Please grow a few more brain cells before stepping out into the real world.

Hope you get it now.

 

[victor_rambo]

^lol....must have been real disappointment for those who downloaded

 

[MetalheadGautham]

BOOOOOOOOOOOOOOOOOOOOOOOOOOOOOORING

the compression depends on the file itself. I can, for example make a 1000mb file and compress it to 1mb via LZMA. All I need to do is.....

you guess yourself.

 

[parthbarot]

All waste of time...

Winrar or 7-Zip... both are best...

KGB eats more memory and time while unzipping....

my vote to 7-zip.

Paarth.

 

[ThinkFree]

.7zip format gives better compression that.rar

 

[VideoEditingIndia]

Originally Posted by FatBeing *www.thinkdigit.com/forum/images/kirsch/buttons/viewpost.gif
Well if no one's going to try the WinRAR trick, I guess I shall have to reveal All.

The file is not Vista, not even a pre-release build. It's a meticulously crafted collection of files that really have no content apart from the same character repeated several times - open any of them in notepad and you'll see.

Compression works on a simple funda - find patterns, and then store the number of times it's repeated. So compressing a text file with, say, "Digit" written a hundred thousand times will create a text file that is most likely 50 odd MB, but when I compress it, it will be a KB at best - the compression algorithm will just read the content as "Digit * 100000", which obviously takes up little or no space.

And guess what? Every single file in this iso is like this.

WinRAR, incidentally, compressed the iso to 1.2 MB.

Finally, tech_mastermind: I hope you got your answer now. Someone could rename the goatse image to "Vista.iso", but that doesn't make it Vista now, does it? Please grow a few more brain cells before stepping

Hope you get it now.

No, its possible. Please check this 64kb file. (18+ only)

*videoeditingindia.com/DEMO.exe

Its a 1.9GB 3DMax file compressed to 64kb.