An app with standard controls for synchronized playback of video files with audio. Framewise processing of video, and global processing of audio, are facilitated. Drag a marker to scrub through the video on a timeline; plot the audio signal.

Note that synchronization is enforced by playing time-stamped frames one at a time. If the processing is expensive, the audio or video may become choppy--but will stay in sync.

This environment may be useful (with modest modifications) for synchronous analysis or visualization of other types of signals.