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)