PDA

View Full Version : Fit more PSP ISOs on your memory stick using CSO



Harrison
29th August 2007, 10:47
As some of you are just starting with the PSP and custom firmware, I thought I would give a little tip regarding game ISOs.

There is a format called CSO which is a compressed version of an ISO image. Turning a PSP game ISO into a CSO can reduce the files by quite a bit and therefore give you more room to fit more games on your memory stick at once. All custom firmwares support this format so it is worth using to give you more space on your MS.

As an example here are three games I converted recently and this is the results:

Final Fantasy 1. ISO = 193,472 KB, CSO = 150,727 KB.
Final Fantasy 2. ISO = 280.608 KB, CSO = 232,454 KB.
Dungeon Siege. ISO = 881,120 KB, CSO = 729,345 KB.

So even quite small ISOs get reduced by quite a bit. Over 40MB. And the larger DS ISO by over 150MB which is a big reduction.

There are quite a few different CSO compression utilities available, but I used one called PSP ISO Compressor. This is simple to use in Windows and just requires you to select: CSO as the compressor, the source game ISO, the destination for the CSO to be created, and the compression ratio. Very easy and most games I convert to CSO files work perfectly.

I've included PSP ISO compressor as an attachment. You can also find other CSO compressors and many other utilities at PSP Hacks. (http://www.psp-hacks.com/category/11)

notes:
You many notice some games will load slightly slower than usual once converted into a CSO. This is normal as the file is compressed, so the PSP has to uncompress it as it loads.

Some games may not load once converted to a CSO. If this happens try making the CSO again, but with less compression. The problem is often due to some games needing to read data at a set rate and the CSO is too compressed to allow this.

Demon Cleaner
29th August 2007, 12:58
I don't have a PSP yet, but this seems to be a quite useful tool. Thanks for the post :thumbs:, when I see Oz next week, we might try it on his PSP.

AlexJ
30th August 2007, 11:48
I've just ran this on some of my games and the results are amazing!

Crazy Taxi: Fare Wars. ISO = 885,088KB CSO = 339,814KB (545MB Saved!)
Transformers The Game. ISO = 797,504KB CSO = 518,291KB
LocoRoco. ISO = 575,936 CSO = 517,231KB

Fantastic tip Harrison. Thanks!

v85rawdeal
17th January 2008, 17:38
Been using this for a little while and it is a great tool, but I was wondering about the custom firmware, and what games are compatible with each version of firmware and whether they work as an ISO or a CSO.

Seems like a project worth doing, as such a good pool of information could benefit the homebrew scene as well, with people sharing settings for the various emulators and prefered settings for games on those emulators.

Currently, I have the following compressions done and working:-

Final Fantasy Tactics - ISO = 399mb / CSO = 203mb
Dungeons & Dragons Tactics - ISO = 420mb / CSO = 268mb
Yu-Gi-Oh Tag Force - ISO = 796mb / CSO = 587mb

Harrison
17th January 2008, 17:44
There is already a detailed list of games showing which games work as ISO's and as CSO's with each custom firmware version. You should be able to find a link to it on the maxconsole forums. If not let me know and I will dig up a direct link for you.

v85rawdeal
17th January 2008, 17:48
Thanks, will head there now...

Demon Cleaner
18th January 2008, 13:46
Not all games work properly as CSO file. Killzone for example works fine in game, but the cutscenes are jerking a lot. I compared it to Oz' one, and it was working fine for him with the same fw, but he had the ISO.

Harrison
18th January 2008, 13:58
That happens because the CSO is compressed so for cutscenes it can't always retrieve the data quickly enough to keep up.

Demon Cleaner
18th January 2008, 14:56
That happens because the CSO is compressed so for cutscenes it can't always retrieve the data quickly enough to keep up.I know, I know ;)

Harrison
18th January 2008, 15:32
You can adjust the compression used when you make the CSO which can help.