JP2005260657A5

JP2005260657A5 -

Info

Publication number: JP2005260657A5
Application number: JP2004070528A
Authority: JP
Filing date: 2004-03-12
Publication date: 2007-01-25

Claims

In a photographing device for photographing a photographing object,
A photographing unit for photographing the photographing object and obtaining a photographed image;
An image processing unit that performs image processing for correcting the captured image acquired by the imaging unit, and the image processing unit includes:
A histogram acquisition unit for acquiring a histogram of the captured image;
A parameter detection unit for detecting a predetermined parameter of the histogram acquired by the histogram acquisition unit;
A feature discriminating unit for discriminating the characteristics of the object to be photographed shown in the photographed image based on the parameters acquired by the parameter detecting unit;
An image correcting unit that corrects the captured image in accordance with the characteristics of the imaging object determined by the feature determining unit;
Comprising
An imaging apparatus characterized by that.

The photographing object is a predetermined document,
The feature determination unit determines the type of document shown in the captured image based on the parameter,
The image correction unit corrects the captured image according to the type of document determined by the feature determination unit;
The imaging apparatus according to claim 1, wherein:

The feature determining unit determines a background color of the document shown in the captured image based on the parameter,
The image correction unit corrects the captured image in accordance with a document type and a background color determined by the feature determination unit;
The imaging apparatus according to claim 2, wherein:

The histogram acquisition unit acquires at least a luminance histogram indicating a luminance distribution in the captured image and a hue histogram indicating a color difference distribution in the captured image,
The parameter detection unit detects at least a minimum value, a maximum value, and a peak value of luminance in the luminance histogram as luminance histogram parameters, and detects a peak value, an average value, and a variance value of color differences in the hue histogram as hue histogram parameters. And
The feature determination unit determines the type and background color of the document based on the luminance histogram parameter and the hue histogram parameter detected by the parameter detection unit;
The photographing apparatus according to claim 2 or 3, wherein

The image correction unit corrects the luminance of the captured image;
The photographing apparatus according to claim 1, wherein the photographing apparatus is characterized in that:

The image correction unit corrects the color of the captured image;
The photographing apparatus according to claim 1, wherein the photographing apparatus is characterized in that:

The image correction unit corrects the distortion of the shooting target indicated in the shot image, and corrects the luminance and / or color of the shot image in which the distortion is corrected;
The imaging device according to claim 6.

A shape-distortion-corrected image data generation unit that generates shape-distortion-corrected image data obtained by correcting the shape-distortion of the document with respect to original image data obtained by photographing the document;
A histogram generation unit that generates a luminance histogram or a hue histogram in the shape distortion correction image data generated by the shape distortion correction image data generation unit;
A document type determination unit that determines whether the document is a monochrome document or a color document based on the luminance histogram or hue histogram generated by the histogram generation unit, or a background color in the document as a document type; ,
A color correction unit that performs color correction on the shape distortion correction image data according to the document type determined by the document type determination unit;
An imaging apparatus comprising:

The shape distortion corrected image data generation unit extracts an image area of the document portion from the original image data and generates shape distortion corrected image data including the document portion.
9. The photographing apparatus according to claim 8, wherein

An image processing method for performing image correction using a computer,
An image acquisition step of acquiring image data showing a predetermined document;
A histogram acquisition step of acquiring a predetermined histogram based on the acquired image data;
A parameter detection step for detecting a predetermined parameter in the acquired histogram;
A document determination step of determining the type and background color of the document based on the detected parameters;
A correction step for correcting the brightness and / or color of the image data in accordance with the determined document type and background color;
An image processing method comprising:

The histogram acquisition step acquires a luminance histogram indicating a luminance distribution in the image data and a hue histogram indicating a color difference distribution in the image data,
The parameter detecting step detects a minimum value, a maximum value, and a peak value of luminance appearing in the luminance histogram as luminance histogram parameters, and detects a peak value, an average value, and a variance value of color differences in the hue histogram as hue histogram parameters. ,
The document determination step determines whether the document type is monochrome and whether the background color of the document is white based on the luminance histogram parameter and the hue histogram parameter,
The correction step performs luminance correction and / or color correction with a correction pattern according to the determined document type and background color.
The image processing method according to claim 10 .

On the computer,
A procedure for acquiring image data showing a predetermined document;
A procedure for obtaining a luminance histogram and a hue histogram based on the obtained image data;
Detecting a minimum value, a maximum value, and a peak value of luminance in the acquired luminance histogram as luminance histogram parameters, and detecting a peak value, an average value, and a variance value of color differences in the hue histogram as hue histogram parameters;
A procedure for determining whether the type of the document is monochrome and whether the background color of the document is white based on the detected luminance histogram parameter and hue histogram parameter;
A procedure for performing luminance correction and / or color correction with a correction pattern according to the determined document type and background color;
A program characterized by having executed.

On the computer,
A shape distortion corrected image data generation procedure for generating shape distortion corrected image data obtained by correcting the shape distortion of the original with respect to the original image data obtained by photographing the original;
A histogram generation procedure for generating a luminance histogram or a hue histogram in the shape distortion correction image data generated in the shape distortion correction image data generation procedure;
A document type determination procedure for determining whether the document is a monochrome document or a color document or a background color in the document as a document type based on the luminance histogram or hue histogram generated by the histogram generation procedure; ,
A color correction procedure for performing color correction on the shape distortion correction image data according to the document type determined by the document type determination procedure;
A program characterized by having executed.