NCLR (NITRO-System Binary Color Palette) files store color palettes for the 2D graphics engine. It follows the [NNS G2D Binary File Format|G2D Binary File Format]. NCLR files use file signature {{'NCLR'}}, or {{'NCPR'}} for the old version of the format.

!! PLTT Block

The {{PLTT}} block stores a color palette in the file. It has the following structure:

||Offset||Type||Meaning
| 0x00   | u32 | Color format. This is the same color format as in {{TEXIMAGE_PARAM}}, where only formats 3 and 4 are used (palette16 and palette256).
| 0x04   | u32 | Extended palette. For standard palettes, set to 0. For extended palettes, set to 1.
| 0x08   | u32 | Palette data size.
| 0x0C   | void * | Pointer to color palette data. This is relative to the start of this structure and fixed up at load time by the library.

!! PCMP Block

The {{PCMP}} block stores information about a compressed palette. Compressed palettes allow unused parts of the palette to not be stored in the file. The structure of this block is as follows:

||Offset||Type||Meaning
| 0x00  | u16  | Number of palettes.
| 0x02  | u16  | Padding space. Official converters typically write {{0xBEEF}} here.
| 0x04  | u16 *| Pointer to index list. This pointer is fixed up at load time. There will be one {{u16}} here for each palette as specified before. These control the index into palette RAM each stored palette is written to. The size of each palette is determined by the color format in the {{PLTT}} block.