Abstract:
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.
Abstract:
A site control unit (12) located at a premises (F) processing video images obtained from a plurality of cameras (22) located about the premises and relaying the presence of a real intrusion to a central station (CS). The site control unit has an image acquisition module (24) receiving video images from the cameras. An image processor (30) processes the images to eliminate possible causes of false alarms of an intrusion and reliably detecting actual intrusions. The processor includes video masking (32) to filter known motion present within a scene, detection (34) detecting movement in unmasked portions of the scene, and recognition (36) classifying the cause of the movement. An indication of an intrusion is given only if the cause is one of a class of predetermined causes representing an intruder on the premises, or an unknown cause. A video recorder (38) records images of the actual intrusion and supplies recorded images to a security system operator (O) who informs authorities of in intrusion. The video recorder produces snapshots (X1-Xn) of a scene viewed by the camera detecting the intrusion detected, authenticates (42) the snapshots, and transmits (46) the snapshots for viewing by the operator.
Abstract:
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.
Abstract:
A friend-or-foe (IFF) identification system (10) comprises a laser generator (12) for generating and transmitting a laser beam (B). A beam splitter (16) divides the laser beam into two beams. One of the beams (B1) is directed along a reference path (P). This beam is reflected back along the path by a mirror (24) positioned at the end of the path. The other laser beam (B2) is directed at an object (T) to be identified as a friend or foe. This second beam reflects off the object and the return, reflected beam is detected. The reflected beam includes a vibration signature of the object under investigation. The return beam and reference beam are processed together to correct the vibration signature of the object for arty distortions. This allows an accurate target signature to be obtained. Next, the target signature is compared against other signatures. The results of the comparison provide the IFF identification.
Abstract:
Apparatus (10) is provided for designating a plurality of objects (E1-E3) within a field of view (FOV) and for thereafter simultaneously tracking each of the objects. A field of view is first defined in which one or more objects may be located. A laser beam generator (12) generates a laser beam (B) and directs it into the field of view. A beam steering mechanism (14) steers the laser beam throughout the field of view for it to strike each of the objects appearing therein. A coder unit (22) generates a code uniquely designating each object. A multiple target tracker (20) thereafter simultaneously tracks each separate object. The tracker controls the steering mechanism to sequentially steer the laser beam to each designated object. The laser, via the steering mechanism, illuminates all, or one or more, of the desginated, tracked targets within the field of view.
Abstract:
A "hardware-in-the-loop" simulator (10) for training people in the use of a missile system to teach target acquisition, missile launch, and missile guidance under simulated battlefield conditions. A battlefield environment (E) including at least one target (T) movable therewithin is created by a simulation module (12). Missile system hardware (H) including the missile acquisition, tracking, and guidance portions is provided. An interface module (20) converts signals produced by the simulating module to an infrared image acceptable by the hardware. The resultant image represents a field-of-view (FOV), including the target, within the battlefield environment. An image module (32) produces a dynamic image representative of the missile's position in the field-of-view. This image is observable by the hardware which utilizes it to determine the position of the missile relative to the target. The hardware also determines if a missile guidance signal is to be sent to the missile to guide it to the target. If so, the interface module is responsive to the guidance signal to simulate, in real-time, the response of the missile to the guidance signal.
Abstract:
Apparatus (10) for acquiring and tracking a missile (M), and guiding it to a target (T). Beacons (18, 19) are carried on the missile to provide an indication of its location in a field of view. One beacon (18) is a xenon beacon which emits energy in a short wave-length portion of the light spectrum. The other beacon (19) is a thermal source which emits infrared radiation in a longer wave-length portion of the spectrum. A sight unit (20) includes both a xenon beacon detector and a forward looking infrared receiver (FLIR). The FLIR provides two independent channels (A, B) of video. An electrical signal developed within the sight unit is separately processed on both of the channels. One channel is used to develop a video display for an operator for target acquisition and tracking. The other channel is used for missile tracking and clutter and countermeasure (CM) rejection. A tracking unit (40) processes the signal to determine missile location relative to the target; and, if corrections to the missile freight path are necessary, a missile control unit (56) transmits them to the missile over wires (W). If two or more objects (M, D1, D2) are located in the field of view, a module (88) of the tracking unit undertakes a "segmentation" process to differentiate and characterize the objects to determine which object is the missile and which is not.
Abstract:
Apparatus (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. If caused by an intruder, an appropriate indication is provided. An algorithm is employed by which differences from one image to another caused by lighting changes, the effects of motion of objects established within the scene, noise, and aliasing effects are identified so as not to produce false alarms. Those remaining segments are further evaluated to determine if there is an intruder present within the scene.
Abstract:
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. An image processor (14) is configured to compare the video image (F) with a previously established reference image (Fr) of the scene to determine if changes have occurred. The image processor includes a memory (20) in which portions of video images (F) 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 portions of the video images for image reconstruction. The playback system enables the memory to be accessed at any desired date and time location so an image of interest can be reconstructed without having to scan stored video images in a date/time sequence. Accessing the memory is done without interrupting the image processor's processing of currently acquired video images.
Abstract:
A method of authenticating a video image created by a camera (V) or similar video device. The image is formed into a first 2-dimensional pixel array (A1) with each pixel (pm,n) represented by a data word of a predetermined length. Additional data words including event information are added to this 2-dimensional array (A1). The formatted array is converted into a second 2-dimensional array (A2) which may be made smaller than the first array by eliminating rows and columns from the formatted array. A first linear vector (A3) is created using the data words in the second array, and a second linear vector (A4) is created by repositioning the data words from the first linear vector in a random pattern. A checksum is created by summing the contents of all of the data words in the second linear vector beginning at a location established by a pre-established formula. A header (H) is formed using the resulting checksum, information identifying the device used to create the image, and the time the image is formed. A cyclical redundancy check (CRC) is performed using all the data words in the formatted array (A1). Results of this operation are also included in the header. The header is attached to the formatted image and is transmitted and stored with the formatted image to subsequently authenticate the contents of the original image.