Image file

Team17's image files (typically with an .img file extension) are usually compressed palleted images.

File format

Type	Size	Name	Description
uint8[4]	4	Signature	Always "IMG\x1A".
uint32	4	File Size	Complete length of the file, in bytes.
string0	-	Description	An optional, null-terminated string, only present in some Worms 2 and Online Worms images.
uint8	1	Bits Per Pixel	Usually 8 (256 colors).
uint8	1	Image Flags	A bit field of the following values: 1 << 6 (0x40) = Image data is compressed; otherwise, it is an array of Width × Height pixels. 1 << 7 (0x80) = Image has a palette, defined as follows:
uint16	2	Palette Color Count	Only if palletized, excludes black^[1].
rgb[colorCount]	3 × color count	Palette Colors	Only if palletized, excludes black^[1]. 3 bytes each color (RGB).
uint16	2	Image Width	In pixels.
uint16	2	Image Height	In pixels.
align4	-	Alignment	Only when embedded in land.dat files, aligns to the next 4-byte boundary.
uint8[]	-	Image Data	Raw image data, according to the above.

↑ ^1.0 ^1.1 The black colour isn't listed in the image palette, nor counted in the "number of colours" word. It is counted as the colour 0, so the palette stored in the file should be loaded starting from colour 1.