Students can submit a video assignment via Kaltura via a Blackboard assignment. 

When a student goes to submit their assignment, rather than uploading a document as they might normally, they can choose to Write Submission > Mashups > Kaltura video as pictured below:

By clicking Add New, they can upload a video from their machine, or record one via their webcam. 

Once the student has added the video and selected it, it will appear in the assignment submission area. They can now choose to Submit.  

The instructor can watch the video and mark it as they would any other Blackboard assignment.