What are the different ways to migrate from OpenCMS to SharePoint 2013
You can export the content to a drive/file system or some shared media, than you will have options to migrate into SharePoint 2013.
Open CMS has a static Export Tool, the static export on demand creates a copy of a resource in the Real File System and the after-publish static export writes out pages after a content was published, so that the RFS contains a full copy of a site. When using the static export, OpenCms automatically adjusts all links to exported resources or to dynamically generated pages. Get complete details here:Â http://www.opencms.org/en/demo/features/version5/staticexport.html
Once, the content is on disk drive (file system), then you may get help from third party migration tools, like, Lepide SharePoint migration.Â
Hope this helps!