Digital video recording system

摘要

A digital video recording system (10) includes a video camera (12) directed at a scene of interest to continuously view the scene and generate video images (F) of the scene at a predetermined frame rate. A frame grabber (16) converts the images to digital signal (vd). A processor (14) processes the signals, comparing the video image represented by a digital signal with a previously established reference (Fr) of the scene to determine if changes have occurred. The processor has a memory (20) in which contents of each digital signal are stored, together with the time and date information as to when the image was acquired. A video playback capability (30) allows the memory to be accessed to retrieve the contents of digital signals so video images produced by the camera can be recreated. The playback system enables the memory to be accessed at any desired date and time location so an image of interest can be reviewed without having to scan video images in a date/time sequence. Accessing the memory is done without interrupting the processor's processing of digital signals for currently acquired video images.