A computer-implemented method of channel change detection and overlay detection for a broadcast output, the computer-implemented method comprises providing a broadcast stream for a display; dividing the display into one or more regions, and selecting at least one of the one or more regions; based on the selected one or more regions, determining a first content associated with the broadcast stream; at a time associated with an insertion point for a second content, determining whether the determined first content associated with the broadcast stream matches a target content associated with insertion of the second content in the broadcast stream at the insertion point; for the first content not matching the target content, blocking the insertion of the second content; and for the first content not matching the target content, performing the insertion of the second content.