The 4-bit Graphics files

Graphics in Aethra are 16 colour (4-bit) palleted. The pallet is:

#FF00FF #0000A8 #00A800 #00A8FC
#A85454 #FCA800 #A85400 #A8A8A8
#545454 #5454FC #54FC54 #000000
#FC5454 #FCA8A8 #FCFC00 #FCFCFC

The graphics data is stored as a simple bitmap: no compression or header information is added. Since the game only used 4 bits per pixel, each byte describes two consecutive pixels. This results in an easy to follow format; just imagine bytes as hex-values: each nibble is a pixel.

The pixels are stored rows × colums, from bottom to top and left to right respectively.

Most files contain only images with a single fixed width × height. However, some files (ICONS.PIC and MONPIC.PIC) contain images of varying dimensions. There is nothing to indicate this inside the file. You need to know the offset and interpret the bytes from that point on as the new dimensions. Fortunately, this is easy enough to do.