Compressing a 1Gb file into 4Mb file

[gazz9496]

there are also different grades of compression apps out there and algorithms in use. I've come across one not readily available to the general public that really is good on complex files but costs alot to get.

frankly you really do get what you pay for on this right now as the development has to be paid for somewhere.

i dare say the compression used on things like the game discs is probably a little bit beyond anything capable by winzip/winrar/7zip.

 

[Britton30]

The Windows 7 install DVD is about 4GB in size and has all versions included. After you install one OS it's size is over 8GB. Somehow MS has compression figured out. May have something to do with all the .bin files?

 

[Barman58]

Due to the nested nature of Windows 7 and the in-place "Anytime" upgrade options available, the install is actually always the same - the image for Ultimate is used for installation but only those options relevant to the licence are activated.

this gives the impression of all versions being on the same disk when in fact a single image is present, giving a compression ratio of about 2:1

 

[Bill2]

Win7 employs the WIM image format which enables compression and "single instancing", thereby reducing the size of image files significantly. Single instancing means that if e.g. images 1, 2, and 3 all contain file A, only a single copy of the file A is stored and images 1, 2, and 3 are pointed to that copy.