PS2 - Any ill effects to using maximum ZSO compression level on ziso.exe? Can it do batches?

[Cyber Akuma]

I was using the frontend/GUI PSXiSO but it's a bit... broken (guess that's why it is listed as beta) but it's just a frontend for several CLI-based compression tools, and they look simple enough to use manually (especially with that GUI being a bit messy to deal with).

However, I noticed that the PSXiSO GUI was always using a compression level of 1, and ziso.exe supports a compression level up to 9. Is there any downside to using a higher compression level? Does it increase chances of breaking something, or could cause the game to not load, or increase load times on either emulators or real hardware? Or is there no downside to using maximum compression besides it taking longer to compress?

Also, can it do batches? I didn't see any obvious mention of that while I was reading through it's CLI commands.

 

[master801]

With higher compression levels, you'll gain slightly to moderately smaller file sizes (depends on the file), but on the downside it'll take longer to decompress when ran, depending on the hardware.

Also, sometimes higher compression can cause compatibility issues.

Compressed ROM files on emulators with moderate to overkill hardware (PC) usually doesn't affect load times (although this is not to say it doesn't happen), but on real hardware, it can definitely cause poor load times due to lesser processing power.

For example, using compressed ISO files (.cso) on an actual PSP will cause slightly to moderately longer load times due to it having to decompress with a weak CPU, and some games will be incompatible.