초록 ▼

A passive range measurement device and method are described which utilizes a digitized image stream derived from images taken by a camera which is also part of the device. The device also includes a digital processor which operates on the image stream to extract the coefficients of an address modifi

A passive range measurement device and method are described which utilizes a digitized image stream derived from images taken by a camera which is also part of the device. The device also includes a digital processor which operates on the image stream to extract the coefficients of an address modification function from which range to each point in the scene, relative camera-scene, and camera-platform orientations may be derived. The extraction process is based upon calculation of a vector field which describes the pixel-to-pixel misregistration between two images. Improvements in the modification function are found from global, then localized averages of the vector field. Thus, a topographic map of the scene which is referenced to the position of the camera and platform is created, and may be used to create a terrain following capability.

대표청구항 ▼

A method for mapping a desired scene of interest from a first and a second image obtained from a first sensor viewing said scene from a first position and a second position, respectively, said first sensor having a predetermined axis system, said method comprising the steps of: A. digitizing said fi

A method for mapping a desired scene of interest from a first and a second image obtained from a first sensor viewing said scene from a first position and a second position, respectively, said first sensor having a predetermined axis system, said method comprising the steps of: A. digitizing said first and second images of said desired scene, thereby creating a first and second digitized image respectively of said desired scene, each of said digitized images having intensity values which are located at different addresses; B. estimating the relative position of said first sensor between said first and second positions, respectively, said relative position described by information relating to the rotation of said first sensor about said axis system, the displacement of said first sensor relative to said axis system, and the direction of the normal to a first plane which is substantially coplanar with said scene, said direction measured relative to said axis system; C. selecting a range along said normal in order to determine the portions of said first image which are positioned on a second plane which is parallel to said first plane substantially at said range from said first sensor; D. modifying said addresses of said intensity values of said second image by use of an address modification function having initial address modification coefficients, thereby producing a first warped image having said intensity values at a plurality of said addresses which said intensity values is substantially equal to said intensity values at each of said corresponding addresses of said first image; E. correlating said first digitized image and said first warped image; F. deriving corrections to said address modification function by correcting said initial address modification coefficients in order to increase the number of addresses having substantially equal intensity values; G. solving in order to correct said relative position information based upon said corrections to said address modification function; H. repeating said steps of modifying, correlating, deriving and solving until the maximum number of said addresses have substantially equal intensity values; I. computing the derivatives of said address modification function having corrected address modification coefficients, with respect to said selected range, for each address of said first warped image; and J. Calculating, for each said addresses of said first image, the altitude relative to said selected range, from said derivatives of said address modification function and the difference in intensity between said first image and said first warped image at each of said addresses.