There is only one file type that uses the .OC3 extension:
openCanvas 3 Event File
File created by openCanvas 3, a drawing program that allows stroke events to be recorded and replayed; saves a recording of the stroke events that took place to create the image; does not save the image itself, which is stored in an .OCI file.
NOTE: Other event files include .OC4 and .OC5 files for versions 4 and 5 of the software, respectively. OC3 files can still be opened in openCanvas 5.
|Portalgraphics openCanvas||Free Trial|
Updated: July 19, 2012