==Chunk types==
===Simple 4 colour graphicpart===
<pre>
byte 0: [bit0-6] width in bytes (1-63) [bit7] flag, if graphic data is compressed
byte 1: width in pixel (1-252)
byte 2: height in pixel (1-255)
if uncompressed:
byte 3-n: linear graphic data (size = byte0 * byte2)
if compressed:
byte 3,4: size of compressed graphic data
byte 5-n: compressed linear graphic data (ZX0 with special SymbOS header)
</pre>
This chunk type can be recognized, if the first byte has a value between 1 and 63(uncompressed) or between 129 and 191 (compressed). The 4 colour graphic data is encoded in CPC Mode 1 format. Every byte contains 4 pixels:
<pre>
bit7 = bit0 of pixel0 (left pixel)
pixel3 = bit4 + 2 * bit0 (right pixel)
</pre>
===Extended 4 and 16 colour graphic===