CTPK

CTPK - CTR Texture PacKage

CTPK is a container file for one or multiple textures that are in various formats readable by the 3ds system. Offsets are relative to the beginning of the header section unless specified.

CTPK Header

Offset	Length	Description
0x0	0x4	Magic "CTPK"
0x4	0x2	Version?
0x6	0x2	Number of Texture Entries
0x8	0x4	Texture Data section offset
0xC	0x4	Texture Data section size
0x10	0x4	Hash section offset
0x14	0x4	Conversion Info section offset
0x18	0x8	Padding

Texture Info Entry

The Header block is followed by a texture info entry for each texture in the container. This block is usually followed by the bitmap size arrays and then the file paths. 0x20 byte aligned.

Offset	Length	Description
0x0	0x4	File path Offset
0x4	0x4	Texture Data Size
0x8	0x4	Texture Data Offset (Relative to texture data block offset)
0xC	0x4	Texture Format
0x10	0x2	Width
0x12	0x2	Height
0x14	0x1	Mip Level
0x15	0x1	Type (0: Cube Map, 1: 1D, 2: 2D)
0x16	0x2	Cube Map Related
0x18	0x4	Bitmap Size Array Offset (Relative to to this block)
0x1C	0x4	Unix Timestamp

Hash Block Entry

The texture info block is followed by a hash entry for each texture entry. 0x8 byte aligned.

Offset	Length	Description
0x0	0x4	Crc32 of the file path
0x4	0x4	Index

Conversion Info Block Entry

The hash block is followed by a conversion info entry for each texture entry. 0x4 byte aligned.

Offset	Length	Description
0x0	0x1	Texture Format
0x1	0x1	Unknown
0x2	0x1	Compressed
0x3	0x1	ETC1 Related (Quality?)

Texture Data Block

This block and all it's texture entries are 0x80 byte aligned.

Texture Formats

Value	Description
0x0	RGBA8888
0x1	RGB888
0x2	RGBA5551
0x3	RGB565
0x4	RGBA4444
0xC	ETC1
0xD	ETC1 + Alpha