Wexos: Imported from avsys wiki

2024-05-01T17:33:00Z

Imported from avsys wiki

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'''GFA''' ('''G'''ood-'''F'''eel '''A'''rchive) is an archive format developed by ''Good-Feel'' and used in some [[Nintendo 3DS]] games and software such as ''StreetPass Mii Plaza''.

= File Format =
The file byte order is always little endian.

== Header ==
Every GFA file begins with a 0x2C byte header structure.

{| class="wikitable"
! Offset !! Type !! Description
|-
| 0x00 || Char[4] || '''File magic'''. Always ''GFAC'' in ASCII.
|-
| 0x04 || UInt32 || '''[[#Version List|Version number]]'''.
|-
| 0x08 || UInt32 || {{Unknown-left|'''Unknown'''. Always 1.}}
|-
| 0x0C || UInt32 || '''[[#File Allocation Table|File Allocation Table]] offset'''.
|-
| 0x10 || UInt32 || '''Size of [[#File Allocation Table|File Allocation Table]]''' in bytes.
|-
| 0x14 || UInt32 || '''[[#GFCP|GFCP]] offset'''.
|-
| 0x18 || UInt32 || '''Size of [[#GFCP|GFCP]]''' in bytes.
|-
| 0x1C || Byte[16] || '''Padding'''.
|}

== File Allocation Table ==
The Header is immediately followed by a File Allocation Table. It has the following structure:

{| class="wikitable"
! Offset !! Type !! Description
|-
| 0x00 || Int32 || '''Number of [[#Node|nodes]]'''.
|}

=== Node ===
Followed by the number of nodes comes all node entries. Each entry has the following structure:

{| class="wikitable"
! Offset !! Type !! Description
|-
| 0x00 || UInt32 || '''File Hash'''.
|-
| 0x04 || UInt24 || '''File name offset'''.
|-
| 0x07 || Byte || {{Unknown-left|'''Unknown'''. Sometimes seen as 0x80.}}
|-
| 0x08 || UInt32 || '''Size of the uncompressed file''' in bytes.
|-
| 0x0C || UInt32 || '''Uncompressed file offset''', starting at the [[#GFCP|GFCP]] offset.
|}

== GFCP ==
The GFCP section contains file data. Its header has the following structure:

{| class="wikitable"
! Offset !! Type !! Description
|-
| 0x00 || Char[4] || '''File magic'''. Always ''GFCP'' in ASCII.
|-
| 0x04 || UInt32 || {{Unknown-left|'''Unknown'''. Always 1.}}
|-
| 0x08 || Int32 || '''Compression type''':
* 0 = Uncompressed
* 1 = BPE
* 2 = LZ77 Wii Raw 10
* 3 = LZ77 Wii Raw 10 (as well?)
|-
| 0x0C || UInt32 || '''Uncompressed size'''.
|-
| 0x10 || UInt32 || '''Compressed size'''.
|}

After follows 4-byte aligned null-terminated strings that represent the filenames of the packed files.

== File Data ==
The compressed data begins just after the the [[#GFCP|GFCP]] header.

= Version List =
{|class="wikitable"
! Version !! Found in
|-
| 0.0.3.1
|
* [[StreetPass Mii Plaza]]
|}

= Tools =
The following tools can handle GFA files:
* (none)

[[Category: 3DS File Formats]]

GFA (File Format) - Revision history

Wexos: Imported from avsys wiki