Edit: For anyone reading this in the future ECMA-119 is freely distributable and seems to conform to ISO 9660. ECMA also have versions of some of the specs referenced by ISO 9660. (ECMA-6, ECMA-35, ECMA-43)
Will do. I was gonna start by reading ISO 9660 and I found out it costs 200 dollars from standards.iso.org. Which is a shame because there’s a bunch of other ISO standards referenced in 9660 which would cost even more money to read. I always heard people reference these standards but I had no idea they were so inaccessible to regular users. But I think I found some kind of annotated copy of the spec to read,