US 9,794,483 B1 · Video geolocation

Abstract

Systems and methods for identifying root causes for and/or correcting pointing error in moving platform imaging. Scene frames captured by a sensor (e.g., a focal plane array, etc.) are digitally transformed to compensate for relative motion between the scene and platform, then motion residuals are computed based on inter-frame scene gradients, and image eigenfunctions are fit to the motion residuals to compute coefficients that may be used to efficiently correct future image acquisition, determine root cause(s) of pointing (e.g., sensor pointing error, scene mean altitude, platform altitude, etc.) errors, and further digitally correct the captured images. Comparisons may be made to a database of residual transformation coefficients based on known or expected relative motion of the platform to the scene and a known or expected pointing angle. Truly moving targets may be identified, removed and re-added after image digital transformation processing.

Claims20

Dependent claims

A system for pointing error corrected imaging by a movable imaging platform including an imaging sensor, comprising:

one or more processors configured to:
receive frames of a scene captured by the imaging sensor, each frame comprising a plurality of pixels;
digitally transform the captured frames with respect to a common field of view (FOV), the one or more transformations compensating for the apparent motion in the scene induced by relative motion between the scene and the movable imaging platform, such that the pixel size and orientation of pixels of the digitally transformed frames are the same;
calculate any motion residuals, comprising any apparent motion, remaining in the digitally transformed frames based on inter-frame scene gradients between the digitally transformed frames;
if any motion residuals remain in the digitally transformed frames,
fit a set of image eigenfunctions to the calculated motion residuals to compute residual transformation coefficients representing a pointing error of the imaging sensor,
apply the set of image eigenfunctions scaled by the residual transformation coefficients to the digitally transformed frames to compensate for the pointing error, and
output the compensated digitally transformed frames.

5 more elements

A method of pointing error corrected imaging, comprising:

receiving by one or more processors frames captured of a scene with an imaging sensor on a moving imaging platform, each frame comprising a plurality of pixels;
digitally transforming, by the one or more processors, the captured frames with respect to a common field of view (FOV), the one or more transformations compensating for the apparent motion in the scene induced by relative motion between the scene and the movable imaging platform, such that the pixel size and orientation of pixels of the digitally transformed frames are the same;
calculating, with the one or more processors, any motion residuals, comprising any apparent motion, remaining in the digitally transformed frames based on inter-frame scene gradients between the digitally transformed frames;
if any motion residuals remain in the digitally transformed frames,
fitting, by the one or more processors, a set of image eigenfunctions to the calculated motion residuals to compute residual transformation coefficients representing a pointing error of the imaging sensor,
applying, by the one or more processors, the set of image eigenfunctions scaled by the residual transformation coefficients to the digitally transformed frames to compensate for the pointing error, and
outputting, by the one or more processors, the compensated digitally transformed frames.

4 more elements

Dependencies are inferred from the claim text.

Video geolocation

Life of this patent

Video geolocation

Life of this patent

Abstract

Claims20