Questions about ISOs and CSOs

Discussion in 'PSP - Hacking & Homebrew' started by CSD, Aug 16, 2007.

  1. CSD
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    CSD GBAtemp Regular

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    I just got a PSP and I'm a bit lost when it comes to the different ISOs and CSOs out there.

    A CSO is, of course, smaller than an ISO. Beyond that, I see nothing but chaos. I've seen different sized ISOs and different sized CSOs for the same game. The difference can be as much as 200MB, which just confuses me. What's going on and why are there different sized ISOs for the same game? (And I'm not saying that the ISO is different from the CSO; I'm talking about different ISOs for the same game.)

    Also, is there a release list like we have for DS roms? Something cohesive to make sense out of all these different files. At this point, I'd be happy for any kind of guide for PSP ISO/CSO releases.
     
  2. delta123

    delta123 GBAtemp Advanced Fan

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    a cso is a compressed iso. thats all it is.

    the advantages that a cso has over a iso is that it is smaller, and that is it.
    a disadvantage is that it might lag the game down a bit because of the compresses data. but if you download a cso and you find that it is laggy, then you can always decompress it to get the iso. so no dilemma.

    but if there are differnt sized iso files that means that the bigger ones are the original untampered iso. the smaller ones usually have something ripped out of them to make them smaller, like music, or voice or video. but usually they tell you in the title if you are downloading a ripped iso.

    but as fas as cso and iso are concerned there is no difference in the games.
     
  3. [M]artin

    [M]artin .

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    There is no lag when it comes to playing CSOs. The only difference is slightly longer load times (but even those CSO load times are faster then an actual UMD).

    I remove certain files from my ISOs and compress them into CSOs all the time and I never experience lag, only slightly longer loading screens. The reason for the 200mb difference is certain files that are removed from the ISO and then compresssed into the final CSO.

    For example, in every PSP ISO there is an "Update" folder that I always delete. It's simply a folder that contains the updates needed to keep your PSP compatible with Sony's latest firmware. Since I run Custom Firmware, however, there's no need for this folder to be contained inside my ISO. Therefore I delete it from the ISO, compress the newly edited ISO into a CSO and voila, a 1300mb ISO becomes a 812mb CSO!
     
  4. VVoltz

    VVoltz The Pirate Lord

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    Hell, even I can use that info.
    [T]hanks [A] [L]ot [M]artin!


    For that you heve won one of the most old of the ancient rewards, the "dancing Kirby":
    (^'-')^ (^'-')> (>'-')> (>'-')>
     
  5. CSD
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    CSD GBAtemp Regular

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    Thanks a lot for the answers [​IMG]

    delta123, I'm glad to know I can decompress CSOs. I've seen files with "ripped" in the title and wondered why such an obvious thing (that the game has been ripped) is being stated. Now I know, heh. Thank you.

    [M]artin, it's very helpful to know that I can remove unnecessary files such as the ones you mentioned and demos and trailers. Also, thanks a lot for the sites.
     
  6. Superstarsaga

    Superstarsaga Member

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    quick question, how do you decompress a cso?
     
  7. Haruspex

    Haruspex GBAtemp Regular

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    I second that and also i want know if there is a program like NDSCRC for PSP releases so you can check their authenticity.
     
  8. gunner6666

    gunner6666 O_O

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    psp iso compressor is reliable for me since it also decompresses cso(and dax if need be)