This page describes the formats/structure of the data stored in RomFS for Home Menu DLC, for themes.

Control Content

The control content has content-index 0. It's unknown what if any of this is Home Menu specific.

RomFS structure:

  • "MetaDataContentHeader.bin": Unknown, size is 0x44-bytes.
  • "ContentInfoArchive_<region>_<lang>.bin" Contains the list of all DLC content available under this DLC title(which can include DLC that's not yet accessible via the shop). <region> can be "USA", etc. <lang>, for the US title: "en", "es", "fr", and "pt".
  • "icons/<decimal_id>.icn" Contains the raw DLC icon image data, without any header. 48x48 tiled RGB565.

ContentInfoArchive entry format, size 0xC8(this file contains the following entry for each of the DLC content):

Relative offset Size Description
0x0 0x4 Content index - 1
0x4 0x4 0x0 = disabled, 0x1 = enabled.
0x8 0x40 char string for the title text.
0x48 0x88 char string for the description text.

The first entry is a "header": contentindex val=1, second word = <total DLC content excluding DLC control content>. The two strings are set to dummy text.

Theme Content

RomFS structure:

  • "bgm.bcstm": Background music, see here.
  • "body_LZ.bin": LZ11 compressed blob containing the rest of the theme data(graphics + optional CWAVs).

Decompressed body_LZ.bin structure

Offset Size Description
0x0 0x4 Version (Must be 1)
0x4 0x1 Unknown
0x5 0x1 0 = disable usage of bgm.bcstm, non-zero = enable usage of bgm.bcstm.
0x8 0x4 Normally zero(not used?).
0xC 0x4 Must be <4. Top screen draw type: 0 = none, 1 = solid color, 2 = solid color with textured squares, 3 = texture.
0x10 0x4 Top screen frame type, when draw-type is 3: 0 = texture1 (regular scrolling speed), 1 = texture0 (no scroll), 3 = texture1 (slow scrolling speed).
0x14 0x4 Offset for the top screen solid color data. Length of data is either 5 or 7, depending on whether the top screen's draw type is 1 or 2. If draw-type = 1, the first three bytes are the background colour, the next adjusts the background gradient (0=none, 255=fade all the way to white at the top), and the last controls the opacity of the squares that float in front of the background.
0x18 0x4 Top screen texture offset, see below.
0x1C 0x4 Additional top-screen texture offset, used with draw-type has value 2. This is optional when using draw-type val2.
0x20 0x4 Must be <4. Bottom screen draw type: 0 = none, 1 = solid color(see below), 2 = invalid, 3 = texture.
0x24 0x4 Bottom screen frame type, when draw-type is 3: 0 = texture4 (regular scroll), 1 = texture2 (no scroll), 2 = texture3 (flipbook scroll, 0 > 1 > 2 > 0), 3 = texture4 (slow scroll), 4 = texture3 (flipbook scroll, 0 > 1 > 2 > 1 > 0).
0x28 0x4 Bottom Screen texture offset.
0x2C 0x4 Must be <2. 1 = enables usage of the following field.
0x30 0x4 Offset to a 0xC-byte block. The block contains four RGB888 colours that affect the cursor, as it expands and contracts. These are the border colour, main colour, unknown, and expanded glow colour.
0x34 0x4 Must be <2. 1 = enables usage of the following field.
0x38 0x4 Offset to a 0xC-byte block. The first six bytes of the block contain RGB888 colours for the 3d folder model. Specifically, its shadowed and main colours, in that order. The other six bytes are unknown.
0x3C 0x4 Must be <2. 1 = enables usage of the following two fields.
0x40 0x4 Offset to the data for texture6.
0x44 0x4 Offset to the data for texture7.
0x48 0x4 Must be <2. 1 = enables usage of the following field.
0x4C 0x4 Offset to a 0xD-byte block. Block contains three RGB888 colours that affect both the cart icon that appears for DSiWare, and the file graphic that appears in folders. In order: bottom shadow, main colour, highlight at the top (folder icon only). The remaining four bytes are of unknown purpose. (Possibly also colours regular icons if they don't have a texture set?)
0x50 0x4 Must be <2. 1 = enables usage of the following two fields.
0x54 0x4 Offset to the data for texture8.
0x58 0x4 Offset to the data for texture9.
0x5C 0x4 Must be <2. 1 = enables usage of the following field.
0x60 0x4 Offset to a 0xD-byte block. Block contains three RGB888 colours controlling the buttons on the bottom screen with arrows on them - downwards sheen, main colour, leftwards sheen. The last four bytes are of unknown use. Note that the arrows themselves are coloured by the next field.
0x64 0x4 Must be <2. 1 = enables usage of the following field.
0x68 0x4 Offset to a 0x9-byte block. Block contains three RGB888 colors for the bottom screen arrows: edge colour, unpressed colour, and pressed colour. Note that this only controls the arrows themselves, not the rest of the button.
0x6C 0x4 Must be <2. 1 = enables usage of the following two fields.
0x70 0x4 Offset to a 0x20-byte block. Related to the colour of the open button on the bottom screen.
0x74 0x4 Offset to a 0x20-byte block. Block normally contains the same data as the previous field's block, and changing it does not appear to have any effect. (???)
0x78 0x4 Must be <3. 1 = enables usage of the following field.
0x7C 0x4 Offset to a 0xD-byte block.
0x80 0x4 Must be <2. 1 = enables usage of the following field.
0x84 0x4 Offset to a 0xD-byte block, related to the bottom screen icon area. Used when the draw-type is set to solid colour. Block contains three RGB888 colours (shadow colour at the top of empty slot, background colour, border colour/shadow colour for the rest of empty slot) and one RGBA8888 (shadow/glow around folder area).
0x88 0x4 Must be <2. 1 = enables usage of the following field.
0x8C 0x4 Offset to a 0x9-byte block, related to the bottom screen outer area. Used when the draw-type is set to solid colour. Block contains three RGB888 colours (bottom stripes, main background colour, subtle edge glow).
0x90 0x4 Must be <2. 1 = enables usage of the following field.
0x94 0x4 Offset to a 0xD-byte block related to the background of folders. Block contains three RGB888 colours (shadow colour at the top of empty slot, background colour, border colour/shadow colour for the rest of empty slot) and one RGBA8888 (shadow/glow around folder area).
0x98 0x4 Must be <2. 1 = enables usage of the following field.
0x9C 0x4 Offset to a 0x20-byte block. Related to the colour of the back arrow in folders.
0xA0 0x4 Must be <2. 1 = enables usage of the following field.
0xA4 0x4 Offset to a 0x15-byte block. The block contains seven RGB888 colours that affect the bottom bottom screen icon-resize and settings buttons. In order: left box shadow (subtle), background colour, border colour, icon gradient colour 1, icon gradient colour 2, pressed colour, right box shadow (subtle).
0xA8 0x4 Must be <2. 1 = enables usage of the following field.
0xAC 0x4 Offset to a 0xC-byte block. The block contains four RGB888 values, of which the first is the background colour for the "press to activate camera" overlay, and the fourth is the text colour of the same overlay. The middle two are unknown.
0xB0 0x4 Must be <2. 1 = enables usage of the following field.
0xB4 0x4 Offset to a 0x6-byte block. The block contains two RGB888 values: the background colour and text colour for the message that tells you how many demo uses you have remaining.
0xB8 0x4 Must be <2. 1 = below audio data section is used, otherwise it's not used.
0xBC 0x4 Audio data section size, this must be <=0x2DC00.
0xC0 0x4 Offset for the audio data section.

The filesize is aligned to 0x10-bytes. The filesize must be at least 0xC4-bytes, due to padding/alignment the first block of data after the header is normally located at 0xD0.

With the solid-color data, there's 5-bytes located at the solid-color data offset. With draw-type has value 2, there's 7-bytes located here. The first 4-bytes located here is RGBA8888 pixel data, the rest is unknown.

With draw-type val2, texture5 is also used(this likely isn't used for the entire top-screen). With draw-type val2, an extra texture with the same format/dimensions as texture5 can be used, when the additional texture offset field is set.

Frame Types

FrameType Description
2 Animated when pointer moved, split into 3 sections of 320*240 and displayed in the order 0 > 1 > 2
4 Animated when pointer moved, split into 3 sections of 320*240 and displayed in the order 0 > 1 > 2 > 1

Textures

ID Color format Texture display dimensions Texture data dimensions Description
0 Tiled RGB565 412x240 512x256 This is the texture used for the top-screen background, when the frame-type is set for this one. Used for backgrounds that don't scroll.
1 Tiled RGB565 1008x240 1024x256 This is the texture used for the top-screen background, when the frame-type is set for this one. Used for backgrounds that scroll.
2 Tiled RGB565 320x240 512x256 This is the texture used for the bottom-screen background, when the frame-type is set for this one. Used for backgrounds that don't scroll.
3 Tiled RGB565 960x240 1024x256 This is the texture used for the bottom-screen background, when the frame-type is set for this one. Split into three separate 320x240 textures that it jumps through like a flipbook.
4 Tiled RGB565 1008x240 1024x256 This is the texture used for the bottom-screen background, when the frame-type is set for this one. Used for backgrounds that scroll.
5 Tiled A8 64x64 64x64 This is used with the top-screen when top-screen draw-type is val2, see above. Used to tile the top screen in much the same way as the white squares that appear when no theme is selected.
6 Tiled BGR888 74x64 128x64 This is used for folder's on the main menu.
7 Tiled BGR888 82x64 128x64 This is used for open folder's on the main menu.
8 Tiled BGR888 36x72 64x128 This is used for 48x48 icon borders on the main menu.
9 Tiled BGR888 25x50 32x64 This is used for 24x24 icon borders on the main menu.

Audio data section

Offset Size Description
0x0 0x4 Unknown
0x4 0x4 Unknown
0x8 Beginning of the audio data entries.

The audio data section contains the sound effects for this theme.

Audio data entry structure:

Offset Size Description
0x0 Y (see below) Additional data for CWAV 6, see below.
Y + 0x0 0x4 CWAV size.
Y + 0x4 0x4 Unknown
Y + 0x8 X (see below) Additional data for CWAV 4, see below.
Y + 0x8 + X CWAV


Structure of the data starting at offset 0x0, from the above entry, for the additional data with CWAV 7:

Relative offset Size Description
0x0 0x10 ?

Y / the size of this block, is 0x10-bytes.

Structure of the data starting at offset 0x8, from the above entry, for the additional data with CWAV 4:

Relative offset Size Description
0x0 0x2C ?

X / the size of this block, is 0x2C-bytes.

It's unknown how exactly the number of CWAVs is controlled. The CWAVs are used for the following:

  • 0: Cursor movement
  • 1: Application launch
  • 2: Certain buttons
  • 3: Cancel buttons
  • 4: When cursor would be moved off the screen, left/right
  • 5: When cursor is moved a screen-worth of icons across
  • 6: Folder buttons

Built-in themes

The built-in themes are stored at Home Menu RomFS:/theme/<Color>_LZ.bin, the format appears to be the same as body_LZ.bin in the theme DLC content.