Removal of poisson false color noise in low-light images usng time-domain mean and variance measurements
First Claim
1. An image processing method for an image consecutively inputted per frame unit, the method comprising:
- a step of capturing the image with a capturing device;
a step of segmenting the image into unit areas comprising a predetermined number of pixels;
a first step of dividing each unit area into a low light region or a high light region by using the brightness of image data contained in said each unit area;
a second step of outputting statistical information from image data contained in at least one unit area divided into the low light region, and detecting and removing Poisson and photon counting noise on the basis of the statistical information, the statistical information being the mean of the unit area;
a third step of detecting a motion pixel from the image data; and
a fourth step of detecting and removing false color noise from the image data on the basis of the detected motion pixel and the statistical information,wherein the step of detecting and removing false color noise uses an area statistical value, the area statistical value determined as
|(x(i, j, t)−
x(i, j, t)2−
σ
2(i, j, t)|,wherein said x(i, j, t) is a pixel value in coordinates (i, j) when time is t,said x(i, j, t) is the mean of the unit area containing coordinates (i, j) when time is t, andsaid σ
2(i, j, t) is the variance in coordinates (i, j) when time is t.
1 Assignment
0 Petitions
Accused Products
Abstract
Disclosed are an image processing method capable of effectively removing noise contained in an image photographed in a low light environment by using statistical information, and a system thereof. There is provided an image processing method for an image consecutively inputted per frame unit, the method comprising: a step of segmenting the image into unit areas comprising a predetermined number of pixels; a first step of dividing each unit area into a low light region or a high light region by using the brightness of image data contained in said each unit area; a second step of outputting statistical information from image data contained in at least one unit area divided into the low light region, and detecting and removing Poisson and photon counting noise on the basis of the statistical information, the statistical information being the mean of the unit area; a third step of detecting a motion pixel from the image data; and a fourth step of detecting and removing false color noise from the image data on the basis of the detected motion pixel and the statistical information.
20 Citations
9 Claims
-
1. An image processing method for an image consecutively inputted per frame unit, the method comprising:
-
a step of capturing the image with a capturing device; a step of segmenting the image into unit areas comprising a predetermined number of pixels; a first step of dividing each unit area into a low light region or a high light region by using the brightness of image data contained in said each unit area; a second step of outputting statistical information from image data contained in at least one unit area divided into the low light region, and detecting and removing Poisson and photon counting noise on the basis of the statistical information, the statistical information being the mean of the unit area; a third step of detecting a motion pixel from the image data; and a fourth step of detecting and removing false color noise from the image data on the basis of the detected motion pixel and the statistical information, wherein the step of detecting and removing false color noise uses an area statistical value, the area statistical value determined as
|(x(i, j, t)−x (i, j, t)2−
σ
2(i, j, t)|,wherein said x(i, j, t) is a pixel value in coordinates (i, j) when time is t, said x (i, j, t) is the mean of the unit area containing coordinates (i, j) when time is t, andsaid σ
2(i, j, t) is the variance in coordinates (i, j) when time is t. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A computer readable storage medium comprising computer-readable instructions which, when executed by a computer, perform a method for processing an image consecutively inputted per frame unit, the method comprising the acts of:
-
a step of segmenting the image into unit areas comprising a predetermined number of pixels; a first step of dividing each unit area into a low light region or a high light region by using the brightness of image data contained in said each unit area; a second step of outputting statistical information from image data contained in at least one unit area divided into the low light region, and detecting and removing Poisson and photon counting noise on the basis of the statistical information, the statistical information being the mean of the unit area; a third step of detecting a motion pixel from the image data; and
a fourth step of detecting and removing false color noise from the image data on the basis of the detected motion pixel and the statistical information,wherein the step of detecting and removing false color noise uses an area statistical value, the area statistical value determined as
|(x(i, j, t)−x (i, j, t))2−
σ
2(i, j, t)|,wherein said x(i, j, t) is a pixel value in coordinates (i, j) when time is t, said x (i, j, t) is the mean of the unit area containing coordinates (i, j) when time is t, andsaid σ
2(i, j, t) is the variance in coordinates (i, j) when time is t.
-
-
9. An image processing system for an image consecutively inputted per frame unit, the system comprising:
-
a computing device having a processor, a memory, and an executable application residing in the memory for processing an image consecutively inputted per frame unit, the executable application comprising; a segment module segmenting the image into unit areas comprising a predetermined number of pixels and dividing each unit area into a low light region or a high light region by using the brightness of image data contained in said each unit area; a spatial hybrid filter outputting statistical information from image data contained in at least one unit area divided into the low light region, and detecting and removing Poisson and photon counting noise on the basis of the statistical information, the statistical information being the mean of the unit area; a motion detector detecting a motion pixel from the image data; and a statistical domain temporal filter detecting and removing false color noise from the image data on the basis of the detected motion pixel and the statistical information, wherein the statistical domain temporal filter uses an area statistical value, the area statistical value determined as
|(x(i, j, t)−x (i, j, t))2−
σ
2(i, j, t)|,wherein said x(i, j, t) is a pixel value in coordinates (i, j) when time is t, said x (i, j, t) is the mean of the unit area containing coordinates (i, j) when time is t, andsaid σ
2(i, j, t) is the variance in coordinates (i, j) when time is t.
-
Specification