This is a model transformation tool that converts Petri nets from the CPN-AMI's CAMI format into Petri Net Markup Language (ISO/IEC 15909-2) and vice versa.
Only Place/Transitions nets are surely supported. Symmetric Nets are partially supported (annotations are exported as text and not as AST), with no guarantee.
Download Cami to PNML Converter from its companion web site.