Artifact removal technique for skew corrected images

Claim 2

An image processing method for processing skew corrected images, the method comprising the steps of: capturing a gray scale image; deskewing said gray scale image; converting said skew corrected image into a first binary image using a first threshold setting and a second binary image using a second threshold setting; generating a map indicative of a difference between the first and second binary images; projecting black pixels in said map onto a line to form a projection profile; and reversing pixels in said first binary image based on said projection profile.

Claim 3

An image processing method according to claim 1 , wherein a direction of projection of said line is based on an original skew angle of said captured image.

Claim 4

An image processing method for processing skew corrected images, the method comprising the steps of: capturing a gray scale image; deskewing said gray scale image; converting said skew corrected image into a first binary image using a first threshold setting and a second binary image using a second threshold setting; comparing said first and second binary images and generating a map indicative of a difference between said first and second binary images; projecting black pixels in said map onto a line to form a projection profile, a direction of projection of said line being based on an original skew angle of said captured image; detecting peaks in said projection profile which are above a specified threshold and generating a line based on said detected peaks, the detected peaks corresponding to artifacts on said captured image; masking black pixels in said map which are adjacent to said generated line; and reversing pixels in said first binary image based on said masked pixels.

Claim 5

An image processing method for processing skew corrected images, the method comprising the steps of: capturing a gray scale image; deskewing said gray scale image; converting said skew corrected image into a first binary image using a first threshold setting and a second binary image using a second threshold setting; comparing said first and second binary images and generating a map indicative of a difference between said first and second binary images; projecting black pixels in said map onto a line to form a projection profile, a direction of projection of said line being based on an original skew angle of said captured image; detecting peaks in said projection profile which are above a specified threshold and generating a line based on said detected peaks, the detected peaks corresponding to artifacts on said captured image; masking black pixels in said map which are adjacent to said generated line; and reversing pixels in said first binary image based on said masked pixels.

Claim 6

A method according to claim 3 , wherein said first and second threshold settings are edge-based image threshold settings.

Claim 7

A method according to claim 3 , wherein said detected peaks represent linearly disposed artifacts in said captured image which each have the following equation: R=x cos( A )+ y sin( A ); wherein x and y are the coordinates of pixels in said map and A is a negative value of the skew angle of the captured image.

Claim 8

A method according to claim 3 , wherein one of said first and second binary images has a normal contrast parameter, and the other of said first and second binary images has a low contrast parameter.

Claim 9

A method according to claim 3 , wherein said artifact is at least one of a line, dash, or dot.

Claim 10

A method according to claim 3 , wherein said captured image is a gray scale image.

Claim 11

A method according to claim 3 , wherein said comparing step comprises the steps of: comparing said first and second binary images in a pixel by pixel manner; and identifying a pixel as a black pixel if there is a difference between the compared pixels and a white pixel if there is no difference between the compared pixels to generate said map.

Claim 12

An image processing method for processing a skewed captured image, the method comprising the steps of: deskewing the captured image; extracting image information from said captured image and storing a resulting image as a first binary image; extracting high contrast details from said captured image and storing a resulting image as a second binary image; comparing said first and second binary images and generating a map indicative of a difference between said first and second binary images; projecting black pixels in said map onto a line to form a projection profile, a direction of projection of said line being based on a skew angle of said skewed captured image; detecting peaks in said projection profile which are above a specified threshold and generating a line based on said detected peaks, the detected peaks corresponding to artifacts on said captured image; masking black pixels in said map which are adjacent to said generated line; and reversing pixels in said first binary image based on said masked pixels.

Claim 13

An image processing method for processing a skewed captured image, the method comprising the steps of: deskewing the captured image; extracting image information from said captured image and storing a resulting image as a first binary image; extracting high contrast details from said captured image and storing a resulting image as a second binary image; comparing said first and second binary images and generating a map indicative of a difference between said first and second binary images; projecting black pixels in said map onto a line to form a projection profile, a direction of projection of said line being based on a skew angle of said skewed captured image; detecting peaks in said projection profile which are above a specified threshold and generating a line based on said detected peaks, the detected peaks corresponding to artifacts on said captured image; masking black pixels in said map which are adjacent to said generated line; and reversing pixels in said first binary image based on said masked pixels.

Claim 14

A method according to claim 10 , wherein said detected peaks represent linearly disposed artifacts in said captured image which each have the following equation: R=x cos( A )+ y sin( A ); wherein x and y are the coordinates of pixels in said map and A is a negative value of the skew angle of the captured image.

Claim 15

A method according to claim 10 , wherein said artifact is at least one of a line, dash, or dot.

Claim 16

An image capture assembly comprising: an image capture section which captures an image; an image deskewing section which is adapted to correct a captured image which is skewed so as to provide for a captured skewed corrected image; a conversion section which converts said skewed corrected image into digital image information indicative of said skewed corrected captured image; and a processing section which receives said digital information and changes said skewed corrected captured image into a first binary image using a first threshold setting and a second binary image using a second threshold setting, wherein said processing section generates a map indicative of a difference between said first and second binary images, projects black pixels in said map onto a line which is oriented based on a skew angle of the captured image to form a projection profile, and reverses pixels in said first binary image based on said projection profile.

Claim 17

An image capture assembly comprising: an image capture section which captures an image; an image deskewing section which is adapted to correct a captured image which is skewed so as to provide for a captured skewed corrected image; a conversion section which converts said skewed corrected image into digital image information indicative of said skewed corrected captured image; and a processing section which receives said digital information and changes said skewed corrected captured image into a first binary image using a first threshold setting and a second binary image using a second threshold setting, wherein said processing section generates a map indicative of a difference between said first and second binary images, projects black pixels in said map onto a line which is oriented based on a skew angle of the captured image to form a projection profile, and reverses pixels in said first binary image based on said projection profile.

Claim 18

An assembly according to claim 13 , wherein detected peaks represent linearly disposed artifacts in said captured image which each have the following equation: R=x cos( A )+ y sin( A ); Wherein x and y are the coordinates of pixels in said map and A is a negative value of the skew angle of the captured image.