Record a paint board

I am building an easy paint board, but I need to record what I paint, so the app could give back a video file to store it or share it. Is this possible with appinventor? What blocks do I need to do it.



I don't want to have a picture file of the result, but the whole process (video file), from the beginning to the end (of course with a rec button to start and to stop at the end).



You  can not do that with App Inventor.    The best you can do is store a series of images of the Canvas, then play the images of the Canvas back as a slide show.