Opening.bnr

Opening.bnr, also known as 00000000.app, is a file related to Wii homebrew development. The file is one of the first read by the Wii when a new DVD is inserted (as is 00000000.app or title.met for channels), and it is used to display the banner (the channel animation). Even though Opening.bnr shares the name with the file on the GameCube, the content of the file has no resemblance to the GC Opening.bnr file.

Description

Opening.bnr consists of two parts, an IMET header which is (almost) identical to the latter of part A (starting from Zeroes_1) in Content.bin (see Content.bin file structure). However, the last 16 bytes contain some random-looking bytes which are, in fact, an MD5 sum of 0x40 to 0x640 in the header.

Opening.bnr is also stored in the console specific encrypted area of content.bin (a copy of icon.bin is in the SD encrypted area). For some of the channels a generic opening.bnr (which doesn't resemble the actual banner) is stored in the NAND under the \META tree as TITLE.MET. Their purpose is unknown. The proper ones can be found in the unencrypted NAND as one of the .app files, content index 0 (you can get this from the TMD). Also some of those the offset to the IMET header is at 0x80 instead of 0x40.

After the header follows an U8 archive. This is an archive consisting of the following contents:

Full Path	Description
/meta/	Directory
/meta/banner.bin	Contains the images and animation displayed when the channel is selected.
/meta/icon.bin	Contains the images and animation displayed when the channel is in the menu.
/meta/sound.bin	Contains the audio that is played when the channel is selected.

banner.bin and icon.bin

The banner.bin and icon.bin files are (usually, though not required to be) LZ77 compressed U8 archives themselves, each with an IMD5 header, containing the MD5 of the file (described below).

More information on LZ77 compression can be found on Wikipedia. Example C# source is available in the Tools and Example Source section.

The banner.bin and icon.bin U8 archives have a file format like this:

Full Path	Description
/arc/	Directory
/arc/anim/	Contains the images and animation displayed when the channel is selected.
/arc/anim/*.brlan	Contains the animation.
/arc/blyt/	Contains the images and animation displayed when the channel is selected.
/arc/blyt/*.brlyt	Contains the layout used in the animation.
/arc/timg/	Contains the images used.
/arc/timg/*.tpl	The images, in standard GC TPL format.

TPL Files

The TPL files are textures. They can be read by the tplx program from the gcube library, and created using gentpl from benzin.

The format is also described in YAGCD at http://pabut.homeip.net:8000/yagcd/chap14.html#sec14.4. It can contain many different independent texture formats, with varying sizes and supports, and can contain multiple textures in one file.

brlan Files

brlan files are described in the Wii Animations section, and can be created and parsed with benzin.

brlyt Files (Layout)

brlyt files are described in the Wii Animations section, and can be created and parsed with benzin.

sound.bin

sound.bin also has an IMD5 header. Currently, three sound.bin formats have been discovered.

Format	Hex Identifier	Description
BNS	0x42 0x4E 0x53 0x20 (BNS )	Similar to the brstm format, always in the NGC-DSP ADPCM format, supports having an intro sound and a loop point.
WAV	0x52 0x49 0x46 0x46 (RIFF)	Standard wav/(16 bit) PCM format, supports having an intro sound and a loop point using the tool Wavosaur (PC). Can be LZ77 compressed.
AIFF	0x46 0x4F 0x52 0x4D (FORM)	Standard AIFF/PCM format, only plays once. Can be LZ77 compressed.

Header Formats

IMD5

typedef struct {
	u32 imd5; // 'IMD5'
	u32 filesize; //size of rest of file
	u8 zeroes[8]; //padding
	u8 crypto[16]; //MD5 of rest of file
} IMD5;

IMET

typedef struct {
    u8 zeroes[64]; // padding
    u32 imet; // "IMET"
    u32 hashsize; // Hash length
    u32 unk;  // The version of the IMET. Always '3'.
    u32 sizes[3]; // icon.bin, banner.bin, sound.bin
    u32 flag1; // unknown
    u8 names[10][84]; // Japanese, English, German, French, Spanish, Italian, Dutch, Simplified Chinese, Traditional Chinese, Korean
    u8 zeroes_2[588]; // padding
    u8 crypto[16]; // MD5 of 0 to 'hashsize' in header. crypto should be all 0's when calculating final MD5
} IMET;

BNS

// Header
typedef struct {
	u32 bns; // 'BNS '
	u32 version; // 0xFEFF0100 endianness and format version check
	u32 filesize; // size of entire BNS
	u16 headersize; // size of BNS header (including chunkinfo)
	u16 chunkcount; // number of chunks
	struct {
		u32 offset; // offset from start of BNS of chunk header
		u32 size; // size of chunk including header
	} chunkinfo[chunkcount]; // info for each chunk
} BNS;

// Chunk header
typedef struct {
	u32 type; // 'INFO' or 'DATA'
	u32 size; // size including header
} BNS_chunk;

// INFO chunk
typedef struct {
	u8 unk; // 0, possibly format control
	u8 loop; // loop flag, 0 = no loop, 1 = loop
	u8 channels; // channel count
	u8 unk2; // 0, padding?
	u16 samplerate; // sample rate (Hz)
	u16 pad; // 0
	u32 loopstart; // loop start sample
	u32 samples; // total sample count
	u32 offset; // offset (in INFO) to channel info offset list
	u32 unk4; // 0, padding?
} INFO_chunk;

// channel info offset list
typdef struct {
	u32 offset[channels]; // offset (in INFO) to channel info for each channel
} channel_info_offset_list

// channel info (for DSP ADPCM)
typedef struct {
	u32 data_offset; // offset (in DATA) of audio data for channel
	u32 info_offset; // offset (in INFO) of DSP info (0x30 byte block)
	u32 unk; // 0
} channel_info;

Tools and Example Source

Name	Language	Author	Description
parse-opening.c	C	magicus	Extracts the contents of the opening.bnr file to a file structure.
LZ77	Python	Marcan	Decompresses LZ77 files.
LZ77Stream.cs	C#	Atacama	C# Stream object for decompressing LZ77 Files.
BNRSound.cs	C#	Atacama	C# Class which processes sound.bin so it can be read as PCM data.
tplx	C	monk	Command line tool included with gcube that extracts the textures in tpl files to seperate tga files.
bnrstruct.c	C	dasda	dasda's structures for the brlan and brlyt files
bannersigner.c	C	icefire	Adds IMET/IMD5 headers to U8 files. IMET is partially broken.