Backgrounds, background masks, interface images and overlays are all in the same Image resource format.
An Image resource begins with the following header:
ITE_IMAGEHEADER
| Type | Order | Name | Description |
| INT16 | LE | width | Image width |
| INT16 | LE | height | Image height |
| INT16 | LE | ? | Unknown/unused? |
| INT16 | LE | ? | Unknown/unused? |
ITE_PALENTRY
Followed by an array of 256 structures as follows:
| Type | Order | Name | Description |
| BYTE | LE | red | Red color component ( 0 - 255 ) |
| BYTE | LE | green | Green color component ( 0 - 255 ) |
| BYTE | LE | blue | Blue color component ( 0 - 255 ) |
Following the palette array is the actual RLE compressed image data. The RLE format for Image resources is SAGA_RLE1.