SYSTEM AND PROCESSOR IMPLEMENTED METHOD FOR IMPROVED IMAGE QUALITY AND ENHANCEMENT

• US 20140119651A1
• Filed: 11/21/2013
• Published: 05/01/2014
• Est. Priority Date: 09/28/2011
• Status: Active Grant

• Current Assignee: The United States Of America As Represented By The Secretary Of The Army
• Original Assignee: US Army Research Laboratory (Government of the United States of America)
• Inventors: Meyers, Ronald E., Deacon, Keith S.
• Granted Patent: US 9,064,315 B2
• Time in Patent Office: Days
• US Class Current: 382/167
• CPC Class Codes: G06T 2207/10032 Satellite or aerial image; Remote sensing
• CPC Class Codes: G06T 5/007 Dynamic range modification applied in cameras using an electronic image sensor H04N23/741, H04N23/743
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction
• CPC Class Codes: G06T 5/90 Dynamic range modification of images or parts thereof

Abstract

System and method for image improvement comprising providing a plurality of frames; determining the value of each pixel within each frame to form a first array of pixel values; selecting pixel locations within a frame; summing the intensity values of those pixels; multiplying the pixels in the first array by the summation of intensity values for selected pixel locations to produce a first product array for each frame; summing the first product arrays; determining the average of first product arrays; determining the average value of each pixel for the plurality of frames to form an a second array of averaged pixel values; determining the average of the summation of intensity values for the selected pixel locations; multiplying the array of average pixel values and the average of the summation of intensity values to form a second product array; subtracting the second product array from the average of first product arrays.

Claims

1. A processor implemented method for image improvement comprising

the following steps not necessarily in sequential order:

providing a plurality of frames of a region of interest;

determining the value of each pixel at each location within each frame to form a first array of pixel values for each frame;

selecting pixel locations within each frame within the plurality of frames;

summing the intensity values for the selected pixel locations within each frame;

multiplying the pixels in the first array of pixel values by the summation of intensity values for the selected pixel locations to produce a first product array for each frame;

summing the first product arrays;

determining the average of first product arrays by dividing the sum of first product arrays by the number of frames in the plurality of frames;

determining the average value of each pixel at each pixel location for the plurality of frames to form an a second array of averaged pixel values for the plurality of frames;

determining the average of the summation of intensity values for the selected pixel locations for the plurality of frames;

multiplying the array of average pixel values and the average of the summation of intensity values for the selected pixel locations for the plurality of frames to form a second product array;

subtracting the second product array from the average of first product arrays to provide an improved image of the region of interest.

2. The method of claim 1 wherein the selecting of pixel locations comprises selecting different pixel locations in different frames and wherein the pixel locations are selected based upon predetermined criteria.

3. The method of claim 1 wherein the summation of intensity values for the selected pixel locations comprises selecting a color for the pixels at the selected pixel locations which is different from the color selected for the pixels in the pixel value array.

4. The method of claim 1 wherein the frames of a region of interest were influenced by the effects of turbulence or were taken in bad or changing weather or were influenced by the effects of low-light.

5. The method of claim 1 wherein the frames of a region of interest comprise sparse image data and wherein an image is reconstructed using sparse data from a plurality of image frames.

6. The method of claim 1 wherein the frames of a region of interest comprise scanned images and wherein the pixel values of each image are determined by illuminating the scanned image and determining the amount of light reflected from the image using at least one photodetector.

7. The method of claim 1 wherein average pixel values can be represented by <

I₁>

;

computing the average of the summation of the intensity values for the selected pixel locations within each frame can be represented by <

I₂>

;

determining the deviation from the summation of the intensity values for the selected pixel locations within each frame can be represented by Δ

I₂=I₂−

<

I₂>

;

determining an array of average pixel values for the series of frames;

can be represented by <

I₁>

;

determining the deviations from the array of average pixel values for each pixel in each frame by subtracting the array of average pixel values from the pixel value arrays to determine positive or negative pixel deviation values can be represented by Δ

I₁=I₁−

<

I₁>

; and

wherein the enhanced image can be represented as <

Δ

I₁Δ

I₂>

=<

I₁I₂>

−

<

I₁>

<

I₂>

.

8. The method of claim 1 wherein the frames comprise regions of interest that are radiation emitting.

9. The method of claim 7 wherein the frames are in color and wherein the I₁ is selected to be one color or wavelength band and I₂ is selected to be a different color or wavelength band.

10. A system for image improvement comprising

at least one processor,

at least one input for inputting frames of data;

at least one display for displaying the image;

at least one memory operatively associated with the at least one processor adapted to store frames of data taken of a region of interest, each frame of data comprising an array of pixels, each pixel having a pixel value, the at least one processor operating to process a plurality of frames of a given region of interest by;

determining the value of each pixel at each location within each frame to form a first array of pixel values for each frame;

selecting pixel locations within each frame within the plurality of frames;

summing the intensity values for the selected pixel locations within each frame;

multiplying the pixels in the first array of pixel values by the summation of intensity values for the selected pixel locations to produce a first product array for each frame;

summing the first product arrays;

determining the average of first product arrays by dividing the sum of first product arrays by the number of frames in the plurality of frames;

determining the average value of each pixel at each pixel location for the plurality of frames to form an a second array of averaged pixel values for the plurality of frames;

determining the average of the summation of intensity values for the selected pixel locations for the plurality of frames;

multiplying the array of average pixel values and the average of the summation of intensity values for the selected pixel locations for the plurality of frames to form a second product array;

subtracting the second product array from the average of first product arrays to provide an improved image of the region of interest.

11. The system of claim 10 wherein the input is connected to an input device comprising one of a scanner, a DVD player, CMOS camera, SPAD array, video camera, smart phone, cell phone, lidar, ladar, television, and CCD camera.

12. A processor-implemented method for image improvement comprising the following steps not necessarily in sequential order:

providing a plurality of first frames;

determining the value of each pixel at each location within each frame to form a pixel value array for each frame;

the pixel locations being arranged horizontally and vertically;

for each of the plurality of first frames, creating a shifted frame in which the pixel values are shifted horizontally and/or vertically from the first frame pixel values;

computing the average frame intensity for the plurality of first frames;

computing the average shifted frame intensity for the plurality of shifted frames;

determining the frame intensity deviation for each first frame by subtracting the average frame intensity for the plurality of first frames from the frame intensity for each first frame;

determining the shifted frame intensity deviation for each shifted frame by subtracting the average shifted frame intensity for the plurality of shifted frames from the frame intensity for each shifted frame;

creating a first subgroup of all locations of pixel values where both the first frame intensity deviations and the shifted frame intensity deviations are positive;

creating a second subgroup of all locations of pixel values where the first frame intensity deviations are positive and the shifted frame intensity deviations are negative;

creating a third subgroup of all locations of pixel values where the first frame intensity deviations are negative and the shifted frame intensity deviations are positive;

creating a fourth subgroup of all locations of pixel values where the first frame intensity deviations are negative and the shifted frame intensity deviations are negative;

for each subgroup, multiplying the first frame intensity deviations by the shifted intensity deviations to create first product arrays for each subgroup;

summing the first product arrays together and dividing by the total number of frames to obtain a second product array for each subgroup;

selecting one or more of the second product arrays to generate an enhanced image.

13. The method of claim 12 wherein the first frame intensity deviations or the shifted frame intensity deviations having zero intensity deviations are grouped in either the first group of all locations of pixel values where both the first frame intensity deviations and the shifted frame intensity deviations are positive or the second subgroup of all locations of pixel values where the first frame intensity deviations are positive and the shifted frame intensity deviations are negative, or to both subgroups, or omitted.

14. The method of claim 12 wherein all second product arrays are combined after reversing the sign of the negative valued second product arrays to generate an enhanced image.

15. The method of claim 12 wherein all second product arrays are combined to generate an enhanced image.

16. The method of claim 12 wherein the frames inputted were influenced by the effects of low-light.

17. The method of claim 12 wherein the frames comprise images of an emitting target.

18. The method of claim 12 wherein the frames are in color.

19. The method of claim 18 wherein the color of the pixels selected for the frame intensity for the first frames is different than the color selected for the shifted frame intensity for the shifted frames.

20. A system for image improvement of low-light or radiation emitting areas comprising:

at least one processor;

at least one memory operatively associated with the at least one processor, the at least one processor configured to execute the method of claim 12.