I really like my Doorbird D101. It does have cloud video for a subscription (otherwise free gives you still images on door press or motion only), but it allows the video to be streamed via http so if you have a server or NAS capable, you can pull the feed into something like ispyconnect.com. In theory it should work with a custom Smartthings device handler for video, so you might be able to trigger your own video capture events via the Smartthings hub?
Most importantly the connection can be via PoE so the response time and connection stability is rock solid.
The API is also quite simple to link to an IFTTT maker applet to handle door press events, etc.