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Romain TISSERANDandClaude Opus 5
0abac3465d
CHDs converted from Redump MIL-CD dumps were rejected with "Unsupported subtype or pre/postgap": the audio tracks of the first session carry their pregap inside their own .bin file, which chdman records as PREGAP:n PGTYPE:V<type> in the CDROM_TRACK_METADATA2 entry. Handle these tracks the way MAME does: - when PGTYPE is prefixed with 'V', the pregap sectors are part of the track data and counted in FRAMES, so INDEX 01 sits `pregap` frames after the previous track and the track data starts `pregap` frames into the CHD - otherwise the pregap only takes up space on the disc - subcode data doesn't change the sector layout, and postgap sectors are never stored: warn about both instead of bailing out Also: - audio tracks of CD-ROM CHDs are stored big-endian, just like the ones of GD-ROM CHDs using the CHGD metadata tag. Not byte-swapping them was the cause of the audio distortion reported with CHD MIL-CDs - the 11400 frame session gap includes the pregap of the second session's first track. Don't count those sectors twice when they're in the image - only treat a multi-track disc as a MIL-CD when its last track is a data track. A mixed mode CD is a single session disc and its data track is the first one - report the lead-out as the first FAD after the last sector, like the CUE and GDI loaders do, instead of one frame earlier Tested on a dozen homebrew MIL-CDs, from 2 to 17 tracks: the CUE and CHD loaders now return the same tracks, sessions and sector data for each of them, and they all boot. Co-Authored-By: Claude Opus 5 (1M context) <[email protected]> Claude-Session: https://claude.ai/code/session_01NfFd8rJc9aTQB7au8yLrqG * cue: don't count the session pregap twice in MIL-CDs The 11400 frame gap added at REM SESSION 02 is the lead-out of the first session (01:30:00), the lead-in of the second one (01:00:00) and the pregap of its first track (00:02:00). When that track has an INDEX 00 of its own, its pregap sectors are stored in the image and were counted a second time, placing the data track 150 frames after the session start reported in the TOC, i.e. after the FAD the boot file is looked up at. Redump lays MIL-CDs out with no INDEX 00 on the second session's track, so none of the images I have hits this. It only shows up with images written by other tools, and is included here because the CHD loader needs the same adjustment to agree with this one. Co-Authored-By: Claude Opus 5 (1M context) <[email protected]> Claude-Session: https://claude.ai/code/session_01NfFd8rJc9aTQB7au8yLrqG