BD-RE long recordings fail to export in MakeMKV: Possible 32-bit limitation

[Taka4]

Environment: Windows 11 64bit, MakeMKV v1.18.2
GUI shows: win(x86-release), Core: win(x64-release)
Observed behavior:
- CS broadcast, 2-hour program (BD-RE) → Decrypt and export succeed
- CS broadcast, 5-hour program (BD-RE) → Decrypt succeeds, export fails
- CS broadcast, 5-hour program (BD-R) → Decrypt and export succeed
Hypothesis:
Decryption works because data is appended relatively to temp, but export uses absolute addressing. If 32-bit integers are used for sector counts or file sizes, overflow may occur with long recordings (>24GB).
However, since the same 5-hour program succeeds on BD-R, this suggests that it is not a simple 32-bit limitation, but rather something specific to BD-RE structure or session management that triggers the failure.
Questions:
- Does MakeMKV internally use 32-bit integers for file size or sector count management?
- Is the failure with long BD-RE recordings caused by this limitation?
- Given BD-R succeeds, could BD-RE-specific management structures be the real cause?
- Are there plans to improve this in the 64-bit build?


supported by Copilot

[Woodstock]

What are you using for the export? MakeMKV does a copy of the contents of the disk, so it should be what is being read. Minus any encryption, of course, but that's not something that would depend on 32- or 64-bit integers.