Techniques for correcting oversaturated pixels in shutterless FIR cameras

1. A method for correcting oversaturated pixels in far-infrared (FIR) images captured by a shutterless FIR camera, comprising:

identifying oversaturated pixels based on a pixel value analysis of an input image, wherein each pixel within the input image is determined to be an oversaturated pixel when an exposure value of the pixel exceeds a predetermined threshold over a predefined time;

designating the identified oversaturated pixels and a number of neighboring pixels around the identified oversaturated pixels in a matrix;

creating an oversaturated pixel mask of the input image, where the oversaturated pixel mask includes the identified oversaturated pixels and excludes pixels not identified as oversaturated pixels;

correcting the oversaturated pixels of the input image using the oversaturated pixel mask, based on a scene-based nonuniformity reduction (SBNR); and

performing a 2-points correction by subtracting a reference point offset value from the input image, and dividing the result of the subtraction by a scene gain value,

wherein the SBNR is configured to correct the oversaturated pixels designated in the matrix by comparing the oversaturated pixels with the neighboring pixels in the input image, and conducting the SBNR more aggressively in a region defined by the oversaturated pixel mask by decreasing an edge-protection threshold to facilitate a faster SBNR-based non-uniformity correction in the oversaturated pixel masked region.

2. The method of claim 1 , further comprising:

monitoring an SBNR correction polarity, and determine that the oversaturated pixels have been corrected when the correction polarity has changed.

3. The method of claim 1 , wherein the pixel value analysis comprises:

analyzing the input image by determining an exposure value of each of the pixels within the input image; and

assigning an oversaturated designation to a pixel when at least one of the pixel and any neighboring pixels exceed a predetermined threshold.

4. The method of claim 3 , wherein the exposure value is calculated based on a captured resistive value associated with each pixel of the input image.

5. The method of claim 3 , wherein an oversaturated designation is assigned when the exposure value of a pixel exceeds the predetermined value over a predetermined period of time.

6. The method of claim 3 , further comprising:

assigning a non-oversaturated designation to a pixel when the pixel and any of the neighboring pixels do not exceed the predetermined threshold.

7. The method of claim 6 , wherein the SBNR includes correcting the oversaturated pixels of the input image incrementally based on neighboring pixels that are designated as non-oversaturated.

8. The method of claim 3 , further comprising:

excluding pixels from the oversaturated pixel mask when a pixel's exposure value equals a maximum exposure value.

9. The method of claim 1 , further comprising:

adjusting the oversaturated pixel mask to include pixels adjacent to the oversaturated pixels.

10. The method of claim 1 , where the oversaturated pixel mask is saved in a storage.

11. A non-transitory computer readable medium having stored thereon instructions for causing a processing circuitry to perform a process, the process comprising:

identifying oversaturated pixels based on a pixel value analysis of an input image, wherein each pixel within the input image is determined to be an oversaturated pixel when a value of the pixel exceeds a predetermined threshold;

designating the identified oversaturated pixels and a number of neighboring pixels around the identified oversaturated pixels in a matrix;

creating an oversaturated pixel mask of the input image, where the oversaturated pixel mask includes the identified oversaturated pixels and excludes pixels not identified as oversaturated pixels;

correcting the oversaturated pixels of the input image using the oversaturated pixel mask, based on a scene-based nonuniformity reduction (SBNR); and

performing a 2-points correction by subtracting a reference point offset value from the input image, and dividing the result of the subtraction by a scene gain value,

wherein the SBNR is configured to correct the oversaturated pixels designated in the matrix by comparing the oversaturated pixels with the neighboring pixels in the input image, and conducting the SBNR more aggressively in a region defined by the oversaturated pixel mask by decreasing an edge-protection threshold to facilitate a faster SBRN-based non-uniformity correction in the oversaturated pixel masked region.

12. A system for correcting oversaturated pixels in far-infrared (FIR) images captured by a shutterless FIR camera, comprising:

a processing circuitry; and

a memory, the memory containing instructions that, when executed by the processing circuitry, configure the system to:

identify oversaturated pixels based on a pixel value analysis of an input image, wherein each pixel within the input image is determined to be an oversaturated pixel when a value of the pixel exceeds a predetermined threshold;

designate the identified oversaturated pixels and a number of neighboring pixels around the identified oversaturated pixels in a matrix;

create an oversaturated pixel mask of the input image, where the oversaturated pixel mask includes the identified oversaturated pixels and excludes pixels not identified as oversaturated pixels;

correct the oversaturated pixels of the input image using the oversaturated pixel mask, based on a scene-based nonuniformity reduction (SBNR); and

performing a 2-points correction by subtracting a reference point offset value from the input image, and dividing the result of the subtraction by a scene gain value,

wherein the SBNR is configured to correct the oversaturated pixels designated in the matrix by comparing the oversaturated pixels with the neighboring pixels in the input image, and conducting the SBNR more aggressively in a region defined by the oversaturated pixel mask by decreasing an edge-protection threshold to facilitate a faster SBNR-based non-uniformity correction in the oversaturated pixel masked region.

13. The system of claim 12 , wherein the system is further configured to:

monitor an SBNR correction polarity, and determine that the oversaturated pixels have been corrected when the correction polarity has changed.

14. The system of claim 12 , wherein the pixel value analysis comprises:

analyzing the input image by determining an exposure value of each of the pixels within the input image; and

assigning an oversaturated designation to a pixel when at least one pixel and any neighboring pixels exceed a predetermined threshold.

15. The system of claim 14 , wherein the exposure value is calculated based on a captured resistive value associated with each pixel of the input image.

16. The system of claim 14 , wherein an oversaturated designation is assigned when the exposure value of a pixel exceeds the predetermined value over a predetermined period of time.

17. The system of claim 14 , wherein the system is further configured to:

assign a non-oversaturated designation to a pixel when the pixel and any of the neighboring pixels do not exceed the predetermined threshold.

18. The system of claim 17 , wherein the SBNR includes correcting the oversaturated pixels of the input image incrementally based on neighboring pixels that are designated as non-oversaturated.

19. The system of claim 14 , wherein the system is further configured to:

exclude pixels from the oversaturated pixel mask when a pixel's exposure value equals a maximum exposure value.

20. The system of claim 12 , wherein the system is further configured to:

adjust the oversaturated pixel mask to include pixels adjacent to the oversaturated pixels.

21. The system of claim 12 , where the oversaturated pixel mask is saved in a storage.