Extended HDI (HDX)
A derivative of the Japanese FDI disk image format, with a more compact header as well as support for images larger than 4 GB.
All offsets are in hexadecimal. The
[Translation] values are for future use.
00000000: Signature (59 54 44 44 20 A8 78 D7 / "YTDD " A8 78 D7) 00000008: Full size of the data in bytes (64-bit) 00000010: Sector size in bytes (32-bit) 00000014: Sectors per cylinder (32-bit) 00000018: Heads per cylinder (32-bit) 0000001C: Cylinders (32-bit) 00000020: [Translation] Sectors per cylinder (32-bit) 00000024: [Translation] Heads per cylinder (32-bit) 00000028: Raw data (size set in offset 00000008)