Abstract: An improved method of tracking a camera in dynamic chroma-keying of the type in which a foreground object is photographed against a multicolored chroma-key screen. The multicolor patterns are created by projection on a monochrome screen, for example by projecting light through a mask on a screen colored with the chroma-key color. The projection of multiple patterns can emulate the use of a single pattern having multiple levels of detail, and can enable lateral tracking of the camera. Sequentially projecting known transformations (for example, rotations) of a pattern adds an extra degree of freedom which further enhances the accuracy of the method.

Abstract: A standard scale used in a photogrammetric measurement system has a polygonal plate having three apexes which are arranged to define a reference plane, where each of the apexes defines a reference point. Another standard scale has a light-guide plate member which has three light-emitting spots for defining reference points. Yet another standard scale has a frame member, and reference-point-forming elements, for defining reference points, arranged on the frame to define a reference plane. A marker used in a photogrammetric measurement system for defining a standard scale has a light-guide plate having a light emitting spot for defining a reference point. Another marker has a polygonal-pyramidal-shaped optical assembly formed from light-guide plates, including a core layer containing fluorescent substances, such that an apex of the optical assembly is defined by an emission of fluorescent radiation therefrom.

Abstract: In a distance detection method, a pair of image data representing a pattern of images is obtained by using a pair of image sensors for receiving optical images. Then, a detection target extracted from each of the image data is captured while sequentially shifting positions of divisions in respective groups of divisions from window part data corresponding to a visual field to provide combinations, each having a pair of divisions, and a correlation value is calculated between each pair of the divisions. Also, a precision at a best correlation point as an indicator of reliability of the best correlation is obtained based on a changing condition of the correlation value near a shift value where the best correlation value has been calculated. Finally, a distance to the detection target is obtained by determining that the detection target is present in the visual field seen through the window corresponding to the window part data only when the precision exceeds a predetermined level.

Abstract: A number of systems and methods for analyzing electronic image signals are provided which include processing the image signal as one or more cells, each comprising a plurality of pixels. For consecutive frames of the monitored image, a set of pointers are generated, each containing a value related to the detail contents of the image. The pointers are used to address a memory array, each pointer corresponding to a row in the memory array and the content of each pointer pointing to a memory element in the corresponding row. For successive frames, the value of each memory element addressed by a pointer is updated.

Abstract: A method for determining degrees of freedom of an object, and in particular, to a device for determining up to six degrees of freedom of a head mount display and a handle. A first camera is attached to a head mount display and senses an optically modulated target. The first camera's video output signal is processed with a digital computer to determine the position and orientation of the head mount display. A second camera is attached to a head mount display and senses an optically modulated target attached to a handle. The second camera's video output signal is processed with a digital computer to determine the position and orientation of the handle.

Abstract: A method for determining up to six degrees of freedom of a camera relative to a reference frame comprises sensing an optically modulated target with the camera and processing the camera's video output signal with a digital computer. The target may have a single pattern, multiple patterns, or patterns of varying size. Multiple targets may also be used. A very wide field of view camera may be used in conjunction with a method for removing geometric distortion from the camera's view. Target patterns may be transmissive, reflective, or retroreflective, or may actively emit light. Asymmetric patterns are used to eliminate ambiguity in the recovery of the degrees of freedom.

Abstract: The presented invention provides the velocity of a moving target from a remote location. A CCD camera receives the image of the target vehicle and records this information on CCD array. The camera then outputs this information in a standard video format such as RS-170, NTSC, or equivalent to the frame grabber circuit card assembly located in the main computer. Custom software along with commercial frame grabber imaging software operates the computer in a Windows or DOS environment. The system will correlate the image of multiple frames stored in the frame grabber circuit card, along with the overlain reference lines and determine the velocity of the target vehicle in miles or kilometers per hour. The image data will be stored in the computer on removable media, along with all pertinent data of the incident including the time/date/location stamp, along with calibration factors and an image of the vehicle operator.

Abstract: A distance measuring apparatus sets a plurality of sub-windows in a picture plane so that the size of each sub-window having a contrast higher than a predetermined value is as small as possible but is greater than a minimum size. Therefore, it is possible to recognize the shape of an object and to measure a distance thereto with high resolution and high precision. For high speed processing, the sub-windows are successively updated in a predetermined cycle in such a manner that only those sub-windows which exist in a region in which a deviation of an image of the object last sensed relative to a previous image thereof is greater than a prescribed value are updated.

Abstract: A distance measuring apparatus of the target tracking type which reduces the amount of data to be processed to allow high rate processing on the real time basis so that a distance to a moving object such as an automobile can be measured while tracking the object. The distance measuring apparatus comprises a plurality of frame memories for storing quantized density data of an image for one frame obtained at a fixed interval of time by imaging a travelling road in a matrix of columns and rows. The quantized data is compared at the same coordinate points to produce density difference data. The density difference data is accumulated for the individual columns and rows in the direction of each column and row, respectively. A preceding vehicle is tracked in accordance with the accumulated column data, the distance to the vehicle in front is measured in accordance with the accumulated row data.

Abstract: Studio camera position and motion may be derived from the camera image by separating out the background and deriving from a background having a number of areas of hue and/or brightness different from adjacent areas estimates of movement from one image to the next. The initial image is used as a reference and amended with predicted motion value. The amended image is compared with incoming images and the result used to derive translation and scale change information. Once the proportion of the reference image contained in an incoming image falls below a threshold a fresh reference image is adopted.

Abstract: A method and apparatus provides instantaneous passive range measurement oard an aircraft for determining the range between the aircraft and a target. The target may either be stationary or a slower moving vehicle. Calculation of the desired range is achieved using the formula: Range=(S/S')V(Cos a)(Cos b) where "S"=apparent target size; "S'"=rate of change of apparent size; "V"=ground velocity; "a"=azimuth angle from aircraft heading to target; and "b"=elevation angle from the aircraft heading to the target. The apparatus consists of an automatic video tracker, a video camera, and a servo controlled aiming platform. The video tracker provides target size data. Resolvers on the aiming platform are utilized to determine the azimuth and elevation angles from the aircraft axis to the target. The azimuth angle is added to the aircraft drift angle to determine the total azimuth angle from the aircraft heading to the target. The drift angle and ground velocity are obtained from the aircraft inertial system.

Abstract: A method and apparatus provides instantaneous passive range measurement oard an aircraft for determining the range between the aircraft and a target. The target may either be stationary and on the earth's surface, or a slower moving vehicle. Calculation of the desired range is achieved using the formula: Range=[Sin a/Sin b] V; where "a"=angle from aircraft heading to target, "b"=turning rate; and "V"=ground velocity. The apparatus consists of an automatic video tracker, a video camera, and a servo controlled aiming platform. A resolver on the aiming platform is utilized to determine the angle from the aircraft axis to the target. This angle is added to the aircraft drift angle to determine the total angle from the aircraft heading to the target. The video tracker is utilized to determine the turning rate of the aiming platform.

Abstract: An automobile distance detection system includes an image camera system which photographs an object which exists in a required range external to an automobile, from a plurality of different directions and obtains a plurality of pictures, and a picture processing unit which processes the plural number of pictures photographed by the camera system and outputs a distance distribution for an entire picture. The image processing unit includes a coincidence calculation element which performs high-speed calculation of a degree of coincidence for each required region, and corresponding to the plural number of pictures photographed by the camera system, and a discrepancy amount determination element determines discrepancy amounts corresponding to the plural number of pictures on the basis of a minimum value for the coincidence, as information relating to the distance distribution.