Image non-uniformity mitigation systems and methods

Patent metadata

Field	Value
Publication number	US-12249043-B2
Application number	US-202217573553-A
Country	US
Kind code	B2
Filing date	Jan 11, 2022
Priority date	Feb 12, 2021
Publication date	Mar 11, 2025
Grant date	Mar 11, 2025

Abstract

Techniques for facilitating non-uniformity mitigation for imaging systems and methods are provided. In one example, a method includes cropping an image based on a defect in the image to obtain a cropped image. The method further includes cropping a supplemental flat field correction (SFFC) map based on the defect in the image to obtain a cropped SFFC map. The method further includes determining a scaling value of a scaling term based at least on a cost function. The method further includes scaling the SFFC map based on the scaling value to obtain a scaled SFFC map. Related devices and systems are also provided.

First claim

What is claimed is:

1. A method comprising
cropping a first image based on a location of a defect in the first image to obtain a first cropped image;
cropping a supplemental flat field correction (SFFC) map based on the location of the defect in the first image to obtain a first cropped SFFC map;
determining a first scaling value of a scaling term based at least on a cost function, the first cropped image, and the first cropped SFFC map; and
scaling the SFFC map based on the first scaling value to obtain a first scaled SFFC map.

2. The method of claim 1 , further comprising applying the scaled SFFC map to one or more images, wherein the cropping the first image and the cropping the SFFC map are further based on a size of the defect.

3. The method of claim 2 , wherein the one or more images comprises the first image.

4. The method of claim 1 , further comprising:
capturing, by a focal plane array, image data, wherein the focal plane array comprises a plurality of infrared detectors; and
processing the image data to obtain the first image, wherein the processing comprises applying a gain and/or an offset to the image data.

5. The method of claim 1 , further comprising applying a damping factor to the first scaling value to obtain a damped scaling value, wherein the scaling is based on the damped scaling value.

6. The method of claim 1 , wherein the determining the first scaling value comprises iteratively adjusting a value of the scaling term to obtain the first scaling value that minimizes the cost function.

7. The method of claim 1 , wherein the cost function is based on the first cropped image, a value of the scaling term, and the first cropped SFFC map.

8. The method of claim 7 , wherein the cost function is based on a gradient of a difference between the first cropped image and the first cropped SFFC map scaled by the value of the scaling term.

9. The method of claim 1 , further comprising:
cropping a second image based on a defect in the second image to obtain a second cropped image;
cropping the SFFC map based on the defect in the second image to obtain a second cropped SFFC map;
determining a second scaling value of the scaling term based at least on the cost function, the second cropped image, and the second cropped SFFC map; and
scaling the SFFC map based at least on the second scaling value to obtain a second scaled SFFC map.

10. The method of claim 9 , wherein the second scaled SFFC map is further based on the first scaling value.

11. The method of claim 1 , wherein the first image comprises a thermal image.

12. A system comprising:
a memory configured to store a supplemental flat field correction (SFFC) map; and
a processing circuit configured to:
crop a first image based on a location of a defect in the first image to obtain a first cropped image;
crop the SFFC map based on the location of the defect in the first image to obtain a first cropped SFFC map;
determine a first scaling value of a scaling term based at least on a cost function, the first cropped image, and the first cropped SFFC map; and
scale the SFFC map based on the first scaling value to obtain a first scaled SFFC map.

13. The system of claim 12 , wherein the processing circuit is further configured to apply the first scaled SFFC map to one or more images.

14. The system of claim 12 , wherein the processing circuit is further configured to apply a damping factor to the first scaling value to obtain a damped scaling value, and wherein the processing circuit is configured to scale the SFFC map based on the damped scaling value.

15. The system of claim 12 , further comprising a focal plane array configured to capture thermal image data, wherein the processing circuit is further configured to apply a gain and/or an offset to the thermal image data to obtain the first image.

16. The system of claim 15 , wherein the focal plane array comprises a plurality of microbolometers.

17. The system of claim 12 , wherein the processing circuit is configured to determine the first scaling value by iteratively adjusting a value of the scaling term to obtain the first scaling value that minimizes the cost function.

18. The system of claim 12 , wherein the cost function is based on the first cropped image, a value of the scaling term, and the first cropped SFFC map.

19. The system of claim 12 , wherein the processing circuit is further configured to:
crop a second image based on a defect in the second image to obtain a second cropped image;
crop the SFFC map based on the defect in the second image to obtain a second cropped SFFC map;
determine a second scaling value of the scaling term based at least on the cost function, the second cropped image, and the second cropped SFFC map; and
scale the SFFC map based at least on the second scaling value to obtain a second scaled SFFC map, wherein the second scaled SFFC map is further based on the first scaling value.

20. The method of claim 1 , wherein the first cropped SFFC map is associated with the same size, shape, and location as the first cropped image.

Assignees

• Teledyne Flir Commercial Systems Inc

Inventors

• Lin Stephanie
• Rodriguez Dylan M
• Kostrzewa Joseph

Classifications

• H04N25/673 Primary

  by using reference sources · CPC title

• H04N23/23

  from thermal infrared radiation · CPC title

• H04N23/80 Primary

  Camera processing pipelines; Components thereof · CPC title

• G06T2207/20132

  Image cropping · CPC title

• G06T2207/10048

  Infrared image · CPC title