Title: Object selection using hit test tracks
Patent application publication number: 20070019889
Publication date: January 25, 2007
Filing date: July 31, 2006 (priority to November 12, 1991)
Link to PDF: 
AIPW Summary: A method for selecting objects from a video track. The user selects a visual area of a single frame and the pixels in the selected visual area are labeled. The labeled pixels are mapped to an item buffer, which is stored in memory with the image frame. By labeling the pixels in the selected area, when the user selects a pixel in a subsequent image frame, the entire selected area can be readily located and an action can be performed relating to the selected area.
Side note: This application is an oldie – there’s a reference to HyperCard (last released in 1998) in paragraph 0003. There are still some references to HyperCard over at the Apple Developer Connection.