I have done some research since Kaltura is an interesting video platform.
The API caters for a wide range of programming languages and environments.
http://corp.kaltura.com/Products/Kaltura-APII have found JavaScript clases at Kaltura API SDK - Native Client Libraries since that would be the viable option to integrate with Marketo.
http://www.kaltura.com/api_v3/testme/client-libs.php The file is js_09-04-2013.tar.tar.gz
Their current implementation ships twp PHP files to be placed on the web server: kaltura.min.js.php and jsmin.php.
That works fine on-premise web servers.
Most native cloud applications do not allow any external files on their web servers.
The solution to integrate with Marketo is setting up the PHP and JS files on your web server and embed them within iFrames on your Marketo landing pages.