Kingdom Hearts II - Image

The game engine uses a custom texture format for all the 2D images to render.

IMGD

Contains a single image. The file structure is defined below. Files of this type have .imd as extension.

FAC

Contains multiple IMGDs aligned by 0x800 and appended one after another. Files of this type have .fac as extension.

The only known FAC files are used by Jiminy’s journal menu.

IMGZ

Contains multiple IMGDs prepended by a specific header. They are appended one after another without any padding. Files of this type have .imz as extension.

File structure

IMGD Header

Offset	Type	Description	Comment
00	uint32_t	Magic code, always 0x44474D49
04	uint32_t	Always 256
08	uint32_t	Bitmap offset
0c	uint32_t	Bitmap size in bytes
10	uint32_t	Palette offset
14	uint32_t	Palette size in bytes
18	uint32_t	Always -1
1c	uint16_t	Image width
1e	uint16_t	Image height
20	uint16_t	2 to the power of image width (2ⁿ)	2⁷ = 128, for example.
22	uint16_t	2 to the power of image height (2ⁿ)	Inversely, to calculate the desired value, run the following calculation (where X is the desired image width/height and n = value): log(X) / log(2) = n
24	uint16_t	Image width divided by 64
26	uint16_t	Image format
28	uint32_t	Always -1
2c	uint16_t	8 when format is 4bpp, else 16
2e	uint16_t	2 when format is 4bpp, else 16
30	uint32_t	Always 1
32	uint16_t	19 when format is 32bpp, else 0
34	uint16_t	3 if 32bpp, 5 if 8bpp or 4 if 4bpp
36	uint16_t	0 when format is 32bpp, else 3
38	uint32_t	Always 0
3c	uint32_t	7 if the image is swizzled, else 3

IMZ header

Offset	Type	Description
00	uint32_t	Magic code, always 0x5A474D49
04	uint32_t	Always 256
08	uint32_t	Header length. Always 16
0c	uint32_t	IMGD count

Image formats

ID	Format
0x00	32 bits per pixel
0x13	8 bits per pixel
0x14	4 bits per pixel