초록 ▼

This invention is a video security system (10) and a method for visually monitoring a scene and detecting motion of an intruder within the scene. A camera (C) continually views the scene and produces a representative signal. A processor (12) processes the signal and produces an image (f2) represente

This invention is a video security system (10) and a method for visually monitoring a scene and detecting motion of an intruder within the scene. A camera (C) continually views the scene and produces a representative signal. A processor (12) processes the signal and produces an image (f2) represented by the signal. This image is compared with a similar image (f1) of the scene from a previous point in time. Segments of the later image which differ from segments of the earlier image are identified. A discriminator (14) evaluates these segments to determine if the differences result simply from lighting changes, or the movement of an intruder within the scene as indicated by surface differences between segments of the respective differences. If caused by an intruder, an appropriate indication is provided. An algorithm is employed by which differences from one image to another caused by global or local lighting changes effects are identified so as not to produce false alarms.

대표청구항 ▼

[ Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:] [1.] A video security system visually monitoring a scene and detecting motion of an object within the scene comprising:imaging means continually viewing the scene and producing a signal representa

[ Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:] [1.] A video security system visually monitoring a scene and detecting motion of an object within the scene comprising:imaging means continually viewing the scene and producing a signal representative of the scene;processor means processing said signal, comparing the signal representing the scene at one point in time with a similar signal representing the scene at a previous point in time, and identifying those segments of the scene at said point in time which differs from segments of the scene at the earlier point in time;discriminator means evaluating those segments of the scene identified as being different to determine if the differences are caused by surface differences which are indicative of the presence of an intruder within the scene, or lighting changes which occur within the scene and do not indicate the presence of an intruder, if the difference is caused by the presence of an intruder providing an indication thereof;said discriminator means including means comparing pixel elements contained in each segment of the scene at one point in time and corresponding pixel elements contained in a corresponding segment from the scene at an earlier point in time; andsaid discriminator means determining a ratio of light intensity between each pixel in a segment with each pixel adjacent thereto, and means comparing the ratio values for the pixels in the segment of the scene at one point in time with the ratio values for the pixels in the corresponding segment of the scene at the earlier point in time.