Video files are first-class citizens in SymmetryMill 3. Play and pause them at will while selecting the motif for your pattern, changing the pattern symmetry, blending repeat units, taking snapshots—and generally doing anything you normally do in SymmetryMill. When you re-apply a snapshot, SymmetryMill automatically jumps to the exact point in the video timeline when the snapshot was taken.
Pattern Explorer fully supports video source files as well. Start the Explorer while a video is playing and then just sit and watch how your pattern story unfolds. Here’s a typical Explorer run: