Description

This property contains (or, when compressing, can be set to contain) custom data. The custom data is (or must be) the following particular format, which can be prepared as many times as you want:

 A 2-byte signature, which can be anything you want *

 A 2-byte length representing the length N of the custom data

 N bytes containing the custom data

*To find out what the already used signatures are contact Jean-Loup Gailly at gzip@prep.ai.mit.edu, who is reportedly the maintainer of a signature list.

Data type

Byte array variant

Default value

Empty