lbee-utils

A small collection of utilities for exporting and importing assets from Little Busters! English Edition

Acknowledgments

The implementations for compression and decompression of CZ1 and CZ3 were derived from GARbro. The implementation of compression and decompression for CZ2 was derived from the implementation in LuckSystem. This project would not have been possible without their amazing work.

Specifications and Info

Each CZ# file starts with a header. The first 14 (0x0E) bytes of the header are common to all CZ# files. The data which come after that are specific to each format, although several CZ# formats do share the same layout.

All byte layouts are in Little Endian.

Common header:

Offset	Ex. Values	ASCII	Purpose
0x00 - 0x03	43 5A 30 00	CZ0	Magic bytes
0x04 - 0x07	24 00 00 00	36	Header length in bytes
0x08 - 0x09	58 01	344	Width of the image in pixels
0x0A - 0x0B	DC 02	732	Height of the image in pixels
0x0C - 0x0D	20 00	32	Bit depth of the image
0x0E	03	3	Color block

The CZ0 and CZ3 header extra data:

Offset	Ex. Values	ASCII	Purpose
0x0F - 0x13	---	---	---[Unknown]---
0x14 - 0x15	58 01	344	Width of image crop
0x16 - 0x17	DC 02	732	Height of image crop
0x18 - 0x19	00 05	1280	Width of image bounding box
0x1A - 0x1B	34 03	820	Height of image bounding box
0x1C - 0x1D	80 02	640	X offset of image, optional
0x1E - 0x1F	02 03	770	Y offset of image, optional
0x20 - 0x23	---	---	---[Unknown]---, optional

The CZ2 header extra data:

Offset	Ex. Values	ASCII	Purpose
0x0F - 0x12	---	---	---[Unknown]---