Issues with compressing ISO to CSO for PCSX2

[_oBSOLEte_]

Hey there,

I've tested to compress some PS2 ISO files. Read about the CSO format being somewhat suggested and well supported by PCSX2 on their forum. I've used the ciso tool on POP!_OS (Compressed ISO9660 converter Ver.1.01 by BOOSTER) with a level 9 compression.

I have tested 4 ISOs and they all boot fine with no noticeable lag whatsoever. They also loaded my previous savegames and I could play a bit. BUT... I recently finished Sly Cooper. By stage 4 before some FMV the game was hanging and I troubleshooted that by going back to using the uncompressed ISO file. Some voiceover dialogs were also not playing with the CSO file I think.

Have you completed games successfully with any compressed PS2 files, with CSO files or some other format? Is the CSO file support not mature enough for PCSX2 compatibility? Or is it a problem on my end with the CISO tool and I should try my luck again with MAXCSO or something else?

 

[JustLooking123]

Unfortunately i haven't tested the CSO format extensively...
I personally use CHD format for compression.
It can compress better, and is well supported by emulators.
You can test it too, and see if it will work better or not.

 

[valosagutas]

The obvious answer is, video games that had concern of space or it's developer's preference to compress their own video games for whatever reason outside of space concerns, they are compressed in certain ways. There are standard and non-standard ways developers compress their video games.

When game is compressed, CPU has to unpack the data and then read it. In this context, when the game is already compressed and then you compressing it again, CPU may cannot unpack the game fast enough so codes of the game work in simultaneously in time sensitive matter.

You can think it as how a factory works. Naturally factories works in a principle of everything has to happen in specific time frames, so when it doesn't they work for nothing and naturally they can ruin the whole factory.

PS2 can use a streaming method that multiple things loaded and processed at the same time. I personally love PS2 because it can manipulate the data in the process of processing in a way during processing it it can change the data (for example it benefitted MGS 3 a lot). When game data cannot be processed in harmony, it happens, they may don't wait for each other to be completed. When this happen the task that was hanged or never happened can crash the game.

Videos in PS2 video games are very sensitive in my experience to rip and mod video games. Some video games require a certain length of videos, otherwise they freeze, crash or never load the next part of the game. It makes ripping and modding PS2 games sometimes a hassle, limits your freedom.

Next topic is if CSO compression method somehow corrupts the original file and if it would ruin the original method of how the game was already compressed: Nope. We can add CSO into "lossless compression method" for a good reason that all the fundamental part of the game is translated back to the original state of the file as it's. So CSO won't cause issue, but if the compression process itself was somehow failed I wouldn't know about that. But it's highly likely not why the game you mentioned had the problem. Nothing wrong with CSO itself, it was because how PS2 behave in certain video games.

But now when you said about CSO was recommended it, I won't mean to say it's worse, technically IDK why someone would recommend it when CHD is a better compression method for PS2 because of the way it's.

Then you may ask me what's key difference between CSO and CHD:

CSO only care about lossless compression.

CHD doesn't only care about file size reduction, it actually cares about integrity of different file formats.

This is hard to explain because I don't mean CSO would corrupt a file, there is more than that. It's just CHD cares more about the individual file formats it detects and leave it as it was in original state of the game.

Because of it I would highly recommend CHD. Then I can say the game may not have an issue if it was compressed via CHD method. But if it still does I would understand because when PS2 was already loading the game, it may not fast enough to decompressed the game within the right time to prevent the game from crashing.

 

[stoicvampirepig]

I only use chd, it's all you need.

 

[Kremiso]

i'm using gzip from quite a while now, just for the isos that really benefit (at least 1GB gain);
the first boot is a couple of secs slower than standard iso, then everything is the same

completed a couple of games, nothing to report

 

[Spike's iconSpike]

I didn't know PCSX2 could Open CSO.
I always seen it in the context of PSP.
And it was known for causing issues with some games even there.
I suggest as other said forget about CSO, use CHD.

 

[secreto7]

Here is all the info and details about compression for different formats for different consoles:

Save disk space for ISOs - Emulation General Wiki

emulation.gametechwiki.com

Apparently CHD works good for DVD based games but is not for CD based ones because of problems it's not preserving TOCs and CUEs.

And it says that CSO gives archival quality depending on the method and settings used. They reccomend the maxcso software.

Also it could be what valosagutas said, if you max compressed the game, perhaps it's interfering with game timings.

 

[aquova]

One thing to note about CHD and PS2 games is that some PS2 games were released on CDs while others on DVDs. It's something I didn't pay enough attention to initially when I started converting things over.

 

[secreto7]

One thing to note about CHD and PS2 games is that some PS2 games were released on CDs while others on DVDs. It's something I didn't pay enough attention to initially when I started converting things over.

Yeah, for example ICO is in CD format.

Here is Redump list for PS2 CD games:

redump.org • Discs

Redump - disc images information

redump.org

 

[_oBSOLEte_]

Thanks guys I'm gonna test CHD next for PCSX2. I wish the emulator would open .7z file like LRPS2 on RetroArch...

i'm using gzip from quite a while now, just for the isos that really benefit (at least 1GB gain);
the first boot is a couple of secs slower than standard iso, then everything is the same

completed a couple of games, nothing to report

Yes it seems logical. The CSO file I had issues with had poor compression ratio, I only gained a bit less than 10% on 2.5 GB, may indicate that the game was already compressed well and converting it was overkill.

 

[secreto7]

Another thing is if someone wants to use CHD, make sure the right parameters and commands are used to create it, like createcd for CDs and createdvd for DVDs, right hunk size, etc.

I was searching for a good guide I saw sometime but I couldn't find it.

Here I found a GUI frontend for chdman:

GitHub - umageddon/namDHC: Windows frontend for CHDMAN - written in Autohotkey

Windows frontend for CHDMAN - written in Autohotkey - umageddon/namDHC

github.com

The thing is that wasn't updated in 3 years.

 

[valosagutas]

Thanks guys I'm gonna test CHD next for PCSX2. I wish the emulator would open .7z file like LRPS2 on RetroArch...

Please let us know here about how it went. I'm really technically interested in the outcome.

I didn't know PCSX2 could Open CSO.
I always seen it in the context of PSP.
And it was known for causing issues with some games even there.
I suggest as other said forget about CSO, use CHD.

I think CSO was popular among PSP because of the low space but CSO was the most popular one. I don't exactly remember if CHD existed then.

If CHD is a newer method than CSO, or the person had no idea about CHD, only in this context why it would make sense to see people recommend CSO instead and why it's bothering when bumping into ancient recommendations because relatively newer advancements regarding the video game consoles in their respective scenes seem to have too much lacking new guides about. I especially had a hard time correcting all the mistakes I was making when I was trying to make my PS2 able to run games without a disc by following guides because my laser had gone blind and I didn't wanna bother fixing it again. It gave me the perspective of gotta always question if there are better ways to do what you wanna do and if there are alternatives. In PS2 scenes experts constantly tell you "you don't have to do it anymore because it was updated" and "you can do this now because of an update" and "it doesn't happen anymore because whole thing changed" and whatnot.

 

[Stookymalarkey]

CSO was popular for PSP since you could use it on the actual hardware. I've heard however that for more memory intensive games like God of War they ran terribly when in CSO format. For PCSX2 there's no benefit to using CSO, and I would recommend using either gzip or chd instead.

 

[aquova]

Does anyone have a list of what formats PCSX2 supports out of the box? i.e. without the user having to go in and unzip some file themselves?

 

[Spike's iconSpike]

Does anyone have a list of what formats PCSX2 supports out of the box? i.e. without the user having to go in and unzip some file themselves?

System > Start file

 

[thecrow2313]

I use chd

Post automatically merged: Today at 4:45 PM

Compressing an .iso image to .gzip is a bore. At the moment I'm compressing God of War to .gzip at ultra level compression using PeaZip. At the moment I've got 31m 28s to go. Going to compare gzip over chd.

 

[Rei de Nada]

Funny i was always thinking CSO was PSP exclusive thing. Anyways.
Just use CHD. Good luck and have fun.

 

[_oBSOLEte_]

Well I got chdman from the mame-tools debian package here. So far, so good. Reached better compression with 30% size reduction and completed the first stage with no cutscene voiceover issue. When I'll reach stage 4 and the crashing FMV I'll let you know.

There was no createdvd argument for the command line tho, and I didnt mention any other parameter than

chdman createcd -i input.iso -o output.chd

But the CHD file booted just fine.

 

[thecrow2313]

Well I got chdman from the mame-tools debian package here. So far, so good. Reached better compression with 30% size reduction and completed the first stage with no cutscene voiceover issue. When I'll reach stage 4 and the crashing FMV I'll let you know.

There was no createdvd argument for the command line tho, and I didnt mention any other parameter than

chdman createcd -i input.iso -o output.chd

But the CHD file booted just fine.

For .iso use createdvd

Post automatically merged: Today at 5:27 PM

Okay, God of War.gz is 6.92 gb & God of War.chd is 6.36 gb
chd wins flawless victory, fatality

Post automatically merged: Today at 5:29 PM

Well I got chdman from the mame-tools debian package here. So far, so good. Reached better compression with 30% size reduction and completed the first stage with no cutscene voiceover issue. When I'll reach stage 4 and the crashing FMV I'll let you know.

There was no createdvd argument for the command line tho, and I didnt mention any other parameter than

chdman createcd -i input.iso -o output.chd

But the CHD file booted just fine.

I'm using chdman 0.277 (chdv5)
Use this command

for /r %%i in (*.iso) do chdman createdvd -i "%%i" -o "%%~ni.chd"

 

[_oBSOLEte_]

For .iso use createdvd

Post automatically merged: Today at 5:27 PM

Okay, God of War.gz is 6.92 gb & God of War.chd is 6.36 gb
chd wins flawless victory, fatality

Post automatically merged: Today at 5:29 PM

I'm using chdman 0.277 (chdv5)
Use this command

for /r %%i in (*.iso) do chdman createdvd -i "%%i" -o "%%~ni.chd"

Seems the version in the deb packages is outdated with no createdvd argument... XD

 

[thecrow2313]

Seems the version in the deb packages is outdated with no createdvd argument... XD

View attachment 71567

Yup seems outdated

Post automatically merged: Today at 5:45 PM

Seems the version in the deb packages is outdated with no createdvd argument... XD

View attachment 71567

I'm using Windows, I don't understand why Linux doesn't have that command for chdman.

Post automatically merged: Today at 5:51 PM

Seems the version in the deb packages is outdated with no createdvd argument... XD

View attachment 71567

disk_image_compression [Batocera.linux - Wiki]

Disc image compression Systems from the 5th and 6th console generation often use optical discs like CD or DVD to store game data. Disc image sizes range from 700 MB (CD), 1.4 GB (GC Mini-DVD), 4.7 GB (single-layered DVD) and even 25 GB (Blu-Ray) for newer systems. Often times only a fraction of...

wiki.batocera.org

That wiki uses createcd command for DVD .isos which idk why though

Post automatically merged: Today at 6:02 PM

Yup seems outdated

Post automatically merged: Today at 5:45 PM

I'm using Windows, I don't understand why Linux doesn't have that command for chdman.

Post automatically merged: Today at 5:51 PM

disk_image_compression [Batocera.linux - Wiki]

Disc image compression Systems from the 5th and 6th console generation often use optical discs like CD or DVD to store game data. Disc image sizes range from 700 MB (CD), 1.4 GB (GC Mini-DVD), 4.7 GB (single-layered DVD) and even 25 GB (Blu-Ray) for newer systems. Often times only a fraction of...

wiki.batocera.org

That wiki uses createcd command for DVD .isos which idk why though

It's a pain in the ass compared to using command lines in shell within Linux while Windows uses batch files to execute commands via chdman. The struggle is real.

GitHub - thingsiplay/tochd: Convert game ISO and archives to CD/DVD CHD for emulation on Linux.

Convert game ISO and archives to CD/DVD CHD for emulation on Linux. - thingsiplay/tochd

github.com

Post automatically merged: Today at 6:06 PM

Seems the version in the deb packages is outdated with no createdvd argument... XD

View attachment 71567

sudo apt install -y --no-install-recommends mame-tools

Post automatically merged: Today at 6:10 PM

Arch Linux - mame-tools 0.277-1 (x86_64)

archlinux.org

Post automatically merged: Today at 6:25 PM

Seems the version in the deb packages is outdated with no createdvd argument... XD

View attachment 71567

Which Linux distro are you using?

 

[_oBSOLEte_]

Yup seems outdated

Post automatically merged: Today at 5:45 PM

I'm using Windows, I don't understand why Linux doesn't have that command for chdman.

Post automatically merged: Today at 5:51 PM

disk_image_compression [Batocera.linux - Wiki]

Disc image compression Systems from the 5th and 6th console generation often use optical discs like CD or DVD to store game data. Disc image sizes range from 700 MB (CD), 1.4 GB (GC Mini-DVD), 4.7 GB (single-layered DVD) and even 25 GB (Blu-Ray) for newer systems. Often times only a fraction of...

wiki.batocera.org

That wiki uses createcd command for DVD .isos which idk why though

Post automatically merged: Today at 6:02 PM

It's a pain in the ass compared to using command lines in shell within Linux while Windows uses batch files to execute commands via chdman. The struggle is real.

GitHub - thingsiplay/tochd: Convert game ISO and archives to CD/DVD CHD for emulation on Linux.

Convert game ISO and archives to CD/DVD CHD for emulation on Linux. - thingsiplay/tochd

github.com

Post automatically merged: Today at 6:06 PM

sudo apt install -y --no-install-recommends mame-tools

Post automatically merged: Today at 6:10 PM

Arch Linux - mame-tools 0.277-1 (x86_64)

archlinux.org

Post automatically merged: Today at 6:25 PM

Which Linux distro are you using?

Thanks! I'm on latest debian based pop!_OS here but I will test things out on Arch on the laptop later. Seems dependent on the MAME version. It's common that things aren't the latest versions in the deb packages, no big deal I'll try to find a newer version on github.

So far stage 2 completed and no problem with the CHD. I should have kept a savestate to further test things out but I was playing with the retroachievements... XD