TKMK00 Compression Format

TKMK00 is a format for some compressed textures used in the Mario Kart 64 title screen and menus.

TKMK00 Decoder

The TKMK00 decoder function is located at 800405D0/0411D0 in the Mario Kart 64 (U) ROM. It takes 4 parameters:

Param	Type	Description
A0	u8*	pointer to input TKMK00 compressed data
A1	u8*	pointer to output buffer (1 byte per pixel)
A2	u16*	pointer to RGBA16 texture output buffer (2 bytes per pixel)
A3	u16	RGBA mask to clear alpha bit for in output (usually 0x0001 or 0x00BE)

Offset	Length	Description
0x00	0x6	File signature “TKMK00”
0x06	0x1	Bit mask used for offsets at 0xC
0x07	0x1	Unused? (always 0x0F)
0x08	0x2	Output texture width in pixels
0x0A	0x2	Output texture height in pixels
0x0C	0x20	Array of 8 offsets, used with bitmask at 0x06