Custom FNV-1 Parameters window is used to configure the Custom FNV-1 checksum algorithm.
To open a Custom FNV-1 configuration dialog, use the Tools » Checksum » Parameters… command.
Select the type of hash to compute: either 32-bit or 64-bit. Enter the algorithm prime, offset basis and select if you want to compute FNV-1 or FNV-1a version of the hash.
Specify the custom algorithm's name and press the OK button to save the changes.