Local contrast adjustment for digital images
First Claim
1. A method for efficiently adjusting a digital image representing data from an infrared sensor, wherein the method is performed by a processor operating in association with a memory storing a computer program, the method comprising:
- receiving, by the processor, image data acquired with an infrared sensor, the image data comprising an imaging array of pixel values, Pij;
formatting for display, using a first signal processing path of the processor, individual pixel values of the imaging array to generate an array of display-formatted pixel values, Pdij;
for individual pixels in the imaging array, determining, using a second signal processing path of the processor operating parallel to the first signal processing path, an average or median pixel value, Paveij, by averaging the values of pixels surrounding the individual pixel;
for individual pixels, replacing at least one of a pixel value, Pij, or a display-formatted pixel value, Pdij, with at least one of an average or median value, Paveij, of pixels neighboring the individual pixel if;
an adjusted pixel value, Δ
ij=Pij−
Paveij, is within a smoothing range S, andadjusted pixel values for the neighboring pixels are also within the smoothing range S; and
displaying an adjusted image on a display, wherein one or more pixels of the adjusted image have a pixel value or a display-formatted pixel value equal to the average or median value, Paveij.
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Accused Products
Abstract
Contrast adjustment of a digital image can include using at least two signal processing paths to adjust a display-formatted pixel value to enhance the appearance of edges in displayed image data. A digital image can be filtered by producing an edge enhancement factor, α, per pixel from at least one look up table (LUT). Digital image data can also be adjusted using at least two signal processing paths, where the image data is adjusted if a pixel value and its neighboring pixel values are all within a smoothing range or where the pixel delta value is outside of a bad pixel range and its neighboring pixel delta values are all within the bad pixel range. In such cases, the image data can be adjusted by replacing the pixel value with an average or median value of the neighboring pixels.
31 Citations
11 Claims
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1. A method for efficiently adjusting a digital image representing data from an infrared sensor, wherein the method is performed by a processor operating in association with a memory storing a computer program, the method comprising:
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receiving, by the processor, image data acquired with an infrared sensor, the image data comprising an imaging array of pixel values, Pij; formatting for display, using a first signal processing path of the processor, individual pixel values of the imaging array to generate an array of display-formatted pixel values, Pdij; for individual pixels in the imaging array, determining, using a second signal processing path of the processor operating parallel to the first signal processing path, an average or median pixel value, Paveij, by averaging the values of pixels surrounding the individual pixel; for individual pixels, replacing at least one of a pixel value, Pij, or a display-formatted pixel value, Pdij, with at least one of an average or median value, Paveij, of pixels neighboring the individual pixel if; an adjusted pixel value, Δ
ij=Pij−
Paveij, is within a smoothing range S, andadjusted pixel values for the neighboring pixels are also within the smoothing range S; and displaying an adjusted image on a display, wherein one or more pixels of the adjusted image have a pixel value or a display-formatted pixel value equal to the average or median value, Paveij. - View Dependent Claims (2, 3, 4, 5)
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6. A method for efficiently adjusting a digital image representing data from an infrared sensor, wherein the method is performed by a processor operating in association with a memory storing a computer program, the method comprising:
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receiving, by the processor, image data acquired with an infrared sensor, the image data comprising an imaging array of pixel values, Pij; formatting for display, using a first signal processing path of the processor, individual pixel values of the imaging array to generate an array of display-formatted pixel values, Pdij; for individual pixels in the imaging array, determining, using a second signal processing path of the processor operating parallel to the first signal processing path, an average or median pixel value, Paveij, by averaging the values of pixels surrounding the individual pixel; for individual pixels, replacing at least one of a pixel value, Pij, or a display-formatted pixel value, Pdij, with at least one of an average or median value, Paveij, of pixels neighboring the individual pixel if; an adjusted pixel value, Δ
ij=Pij−
Paveij, is outside a bad pixel range B, andadjusted pixel values for the neighboring pixels are within the bad pixel range B; and displaying an adjusted image on a display, wherein one or more pixels of the adjusted image have a pixel value or a display-formatted pixel value equal to the average or median value, Paveij. - View Dependent Claims (7, 8, 9, 10, 11)
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Specification