Converting to CHDs for certain cores

I’m in DIRE need of space, and the OCD in me needs to get a standardized file-type on some of these systems.

UPDATE - I have compressed these files, update post at post #26 in this thread contains results!

TL;DR – I need to compress the bejesus out of my disc games, CHD seems like the way to go, how do I do this for each system to get into the new chd format, and also how to convert the old chd format on DC to the new.

NEC Turbo-Grafx-CD - Complete US set, with a bit of JP games. Some of these are in bin/cue and others in iso/cue. (Yes, with a cue file)27.5GB

Panasonic 3DO - Near complete US set, all in iso format – 76.8GB

Sega CD - Complete US set. (I think) All in bin/cue – 70.9GB

Sega Dreamcast - Near Complete US set, with a good amount of JP games. All official games are * old * CHD versions of GDI files. As well as cdi for homebrew/prototypes. – 178GB

!!!Regarding Dreamcast CHDs!!! - based on a previous conversation with @Awakened and some testing, It’s come to my attention that the ReDream core only accepts the * new * CHD format; while Reicast only accepts the * old * CHD format. This leads to 2 questions.

1.) reicast_libretro is currently my primary DC emulator. Is ReDream in a place where it’s worth switching over? I mostly play Sonic and the Fighting Games.

2.) Regardless of #1, based on the progression of ReDream, it will someday overtake the Reicast core. So, how do you convert the OLD chd files, to the NEW standard? Is there a straight conversion, or would I have to unconvert CHD to GDI and the re-convert to the new CHD?

Sega Saturn - All bin/cue files, full US set and some JP (Need a lot more JP) – 120GB

Sony Playstation – Just under 1,000 discs, all bin/cue. – 461GB

Sony Playstation 2 – Ok… so this I’m trying to convert to gz, but JUST to give you an idea of how much room I need, this is sitting at just under 1,000 discs, all CDs are in bin/cue while all DVDs are in iso. – 2.74TB

My Hard Drive that everything is kept on is only a 4TB external (so like 3.63TB or so) I need to convert these disc systems to make room for the PS2 games primarily, but also some extra space for lingering JP games and some Wii titles I’ve yet to grab. (All WiiCube titles are in gcz format)

Also, MAME is sitting at like 515GB Roms (split) + CHDs (merged) So, any advice on compressing that nonsense is much appreciated as well.

You can easily and with a batch, compress PS2 Isos to CSO which will compress better than GZ, and Bin+Cue CD games can be converted to Iso with a tool, and then compress them to CSO as well.

If you pay attention to CHD MAME games, as I recall, most games will have some emulation problems, and if you filter for those that will play without issues, you can make a lot of room eliminating non-working titles.

I believe all other systems you mentioned above MAME and PS2 are OK to be compressed to CHD, I have all those systems in CHD, including NEO GEO CD, a lot of space is spared doing this.

You did not mention PSP, like PS2, PSP games can also be compressed to CSO.

Regarding Dreamcast, I actually use NullDC and Demul until I can totally replace it using RA cores, Shenmue don`t work correctly under the current DC cores.

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Does PCSX 2 natively run CSO though? I think I might have heard some PS2 games have issues with CSO too. Can’t recall exactly…

How do I convert to CHD for these systems? I had a batch file for GDI to CHD but it’s the old version that isn’t being used anymore.

Is there a program that does these now?

As for PSP, I did forget to mention that one. I have all those converted to CSO: 102 files at 64.9GB Which I “think” is round-about the entirety of what I wanted for that system. Still need to do a full-list comparison though.

It does suck Shenmue doesn’t run in RA, but I’ve honestly held off playing those 2 again because I KEEP hearing rumors about the HD remasters prior to Shenmue 3 hitting… and even in 2001 those controls were ROUGH lol

Lastly, How would I go about sorting out those games? There’s like 38,000 or so files in my MAME directory :open_mouth:

Honestly I think just hitting PSX with CHD would make a big difference, if nothing else.

I tried to PBP them once, but I had several games that ran into problems with that format :frowning:

@SkyHighGam3r, a really good guy helped with this batch, I can’t recall his name now but I’ll surely mention him as soon as I can.

All you need to do is edit the set rompath= line to the bin+cue files you want to convert to CHD, they can be multi track bins and will work without problems in a single CHD. Don’t forget to point the destination folder out in set destpath=, this will be the folder where your CHDs will be stored.

Try compressing/converting your bin+cue games from a different drive to another, I tend to do this to have a faster compression and to span my HDD life.

I don’t know if 3DO games can be used as CHD for now, I believe it’s the only system left for me.

Let me know if you need help with this batch.

PCSX2 can run CSO natively, provided you stick to the latest builds, the 1.4 stable is really old and the latest nighties are OK with new features.

As for the MAME CHDs, it’s up to you really, I have something like 500 best arcade roms in my setup, and these include few CHD games, I think they are SFIII, Killer Instinct 1 & 2, etc. I believe my custom arcade setup has less than 5GB, it’s my personal essentials pack.

I have all my PS2 collection in CSO, all games works flawlessly, it’s around 1TB with 650 games.

I still use PBP for the PS1, but only for multi disc games, since a single PBP can have 2,3,4 or 5 discs inside one file, it makes my life much easier when I need to switch discs using RA’s open/close tray options. Yeah, some games didn’t work in PBP, like Road Rash - Jailbreak, Castlevania SOTN, etc., fortunately all those that didn’t work in PBP works perfectly in CSO, and they are single disc games.


It took me a minute to wrap my head around how to edit that batch file, but now I got it!

I’m converting each letter one at a time (all #, then all A, then all B) and this also gives me an opportunity to remove some garbage games I ended up with (Like 100% Star… wtf is that lol)

This should all way WAY help in getting my file sizes down, which is a total life-saver lol.

As always, you’re a massive help Aorin. Much much appreciated.

You’re welcome Sky, let me know when you reach PS2 so I can also help with CSO compression, MAXCSO was updated some time ago, it compresses better and a little faster than older versions, it’s really easy to use, just drag your PS2 isos on maxcso.exe and it will compress them. PS2 CD-Rom games comes in Bin+Cue, there’s a simple tool that converts them to Iso, and then you can compress them to CSO, most will end up in less than 500 Mb (the CD rom games).

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I’m so glad you told me this lol I started to convert a couple last night and it about killed my CPU haha. I am pretty sure I’ve got the old maxcso. Where do you get the new one from?

Right now my PSX and PS2 are on different hard drives so I’m sort of working on both on different machines.

Also that’s great news about converting to ISO. I actually wanted to do that anyway in case I ever needed to put a copy in my physical PS2. I remember I did that like 10 years ago to get Way of the Samurai to work on the ESR patch thing.

Maxcso releases are on github, I just uploaded it to Google Drive and the tool that will convert Bin+Cue to Isos as well, the latter is pretty straightforward and an explanation on how this tool works is unneeded, it will only convert a game at a time though, not a big deal.

Note that Maxcso is CPU intensive just like 7z, I converted the PS2 games before going to bed for a few days. I don’t recommend you try using your PC while compressing your isos.

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Thanks man! I’ll have to give these a try tonight.

Do you think the compression has improved enough that I should bother uncompressing, and then recompressing the PSP stuff with this version? Or would the gains be negligable do ya think?

Either way man, I seriously appreciate it.

This is something I asked myself when compressing PS2 stuff, since my PSP collection was in CSO already. I don’t think it would make a huge difference, really, it’s too time consuming, maybe to gain less than 500 Mb in my current set that contains 600 titles or less. Probably far less than 500Mb.

Hey thanks for all the info on this stuff. You’ve made doing all this very easy.

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Is there any core/emulator that supports both CISO and CHD?

Ciso for what system, Wii? If so, I don’t use GameCube or Wii systems in Retroarch so I can’t tell.

Like ppsspp or other emulators like pcsx2, would there be any point in either supporting chd? I’m not sure how ciso would compare to chd.

Ciso is an old alternative for PSP games, I believe Wii also uses this compression for isos. CSO is the way to go for both systems (PSP and PS2), they are two systems I use the standalone emulators, being that only PSP has a core for Retroarch now.

Isn’t CISO just a program that creates CSO files? I don’t think CISO is a different format. It looks like MaxCSO is the better one to use now though.

“Compared to other tools like ciso and CisoPlus, maxcso can run much faster and achieve the same compression. Use --fast to get the fastest compression, which matches level 9 in other tools.”

I’ve mainly looked through here

Oh OK, I thought ciso was another compression. Anyways, stick to maxcso, it’s a newer tool and will compress better than the others.

Consider deleting ‘mechanical’ games. Slot machines, etc.

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I have some questions here: Can I compress multi disc games to single CHD? Will that work with emulator? How can I convert back to bin+cue if I need to burn the image to disc? Can I play FLAC tracks inside .chd file directly with audio player (preferably foobar2000) and what FLAC compression level is used BTW (I hope 8)?