An image signal processor (ISP) processes received image frame data. In order to reduce power consumption caused by the processing of substantially similar image tiles of received image frames, differential processing may be used to determine which image tiles of a received image frame should be processed by the ISP, based upon a comparison between the received image tiles and previously received image tile data. In addition, differential processing may be automatically disabled in response to a determination that the image frames are too different from each other to realize any savings in processing resources or memory usage, and reenabled in response to a determination the received image frames are similar enough such that power savings can be realized through differential processing.