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ranger_danger 15 hours ago

Is CD-ROM subchannel data accurately emulated for both audio and data modes?

polpo 15 hours ago | parent [-]

Currently, it implements the ATAPI READ SUB-CHANNEL command and fully supports the current position data format code. Other format codes like ISRC and UPC currently return dummy data, but wiring that up would be pretty straightforward. Supporting image formats like CloneCD's .ccd/.img/.sub that store arbitrary subchannel data also seems doable, but would definitely be more work.

easyThrowaway 9 hours ago | parent [-]

The annoying part of .ccd files is the lack of support in the specifications for DPM data. It was officially used just for some old Karaoke machines and VDJing mixers, but more importantly for retrogaming aficionados, it was used by SecuROM and Starforce copy protections.

Can't think of an open format with support for that, IIRC not even CHD files store them.

selfhoster11 8 hours ago | parent [-]

MDF/MDS isn't open, but could possibly be reverse-engineered enough to read the DPMS data.

mos87 7 hours ago | parent [-]

CDEMU/libmirage support both CCD et al and MDF/MDS images. Mixed modes, etc - the whole shebang. How good the copyright protection emulation is I cannot say tho.

easyThrowaway 7 hours ago | parent [-]

I could be utterly wrong on this, but AFAIK the "emulation" in tools like Daemon Tools or Alcohol was only required when the disc image was created with partial or missing DPMS/subchannel data; If the virtual drive provides transparently the required stream the copy protection should be none the wiser on the actual drive emulation.