Scene-based non-uniformity correction for detector arrays

A scene-based non-uniformity correction (SBNUC) method for correcting values of gain and level coefficients of a set of correction coefficients for a scanning detector array, the scanning detector array comprising a plurality of detector channels, the method comprising the steps of:

• generating a preliminary level correction factor for each detector channel using a frame of input scene data;
• generating a gain correction factor for each detector channel using the frame of input scene data;
• generating a gain-induced level correction factor for each detector channel based upon the gain correction factor;
• and
• updating existing values of the gain and level coefficients for each detector channel using the preliminary level correction factor, the gain-induced level correction factor, and the gain correction factor for each detector channel.

An apparatus for providing corrected values of gain and level coefficients of a set of correction coefficients for a scanning detector array, comprising:

• a processor unit coupled to a scanning detector array, the processor unit being configured to:
• modify first values of the gain and level coefficients using at least one frame of image data collected from out-of-focus multiple-temperature imagery by the scanning detector array;
• and
• determine updated values of the gain and level coefficients using a scene-based non-uniformity correction (SBNUC) routine applied to scene data corresponding to focused scene imagery.

An apparatus for providing corrected values of gain and level coefficients of a set of correction coefficients for a scanning detector array, comprising:

• a processor unit coupled to a scanning detector array, the processor unit being configured to:
• generate a preliminary level correction factor for each detector channel using a frame of input scene data;
• generate a gain correction factor for each detector channel using the frame of input scene data;
• generate a gain-induced level correction factor for each detector channel based upon the gain correction factor;
• and
• update existing values of the gain and level coefficients for each detector channel using the preliminary level correction factor, the gain-induced level correction factor, and the gain correction factor for each channel.