Imaging apparatus, image processing method for imaging apparatus, recording medium and carrier wave signal

• US 20060043264A1
• Filed: 08/31/2005
• Published: 03/02/2006
• Est. Priority Date: 09/02/2004
• Status: Active Grant

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Sakurai, Keiichi
• Granted Patent: US 7,643,701 B2
• Time in Patent Office: Days
• US Class Current: 250/208.100
• CPC Class Codes: G06T 3/00 Geometric image transformations in the plane of the image
• CPC Class Codes: G06T 5/006 Geometric correction correction of chromatic aberrations adapted to be used in an image pickup device containing an electronic image sensor H04N23/10; detecting, correcting, reducing or removing artefacts resulting only from the lens unit, e.g. flare, shading, vignetting or "cos4" H04N25/61
• CPC Class Codes: G06T 5/80 Geometric correction
• CPC Class Codes: G06V 30/1478 of characters or characters lines
• CPC Class Codes: H04N 1/00283 with a television apparatus
• CPC Class Codes: H04N 1/047 Detection, control or error compensation of scanning velocity or position H04N1/0402 and H04N1/17 take precedence
• CPC Class Codes: H04N 1/195 the array comprising a two-dimensional array or a combination of two-dimensional arrays
• CPC Class Codes: H04N 1/19594 using a television camera or a still video camera
• CPC Class Codes: H04N 1/387 Composing, repositioning or otherwise geometrically modifying originals
• CPC Class Codes: H04N 2201/0436 Scanning a picture-bearing surface lying face up on a support H04N2201/0434 takes precedence; using cylindrical picture bearing surfaces H04N1/06; with manual scanning H04N1/107
• CPC Class Codes: H04N 2201/04703 using the scanning elements as detectors, e.g. by performing a prescan
• CPC Class Codes: H04N 2201/04717 on the scanned sheet, e.g. a reference sheet
• CPC Class Codes: H04N 2201/0472 on or adjacent the sheet support
• CPC Class Codes: H04N 2201/04732 Detecting at infrequent intervals, e.g. once or twice per line for main-scan control
• CPC Class Codes: H04N 2201/04787 by changing or controlling the addresses or values of pixels, e.g. in an array, in a memory, by interpolation
• CPC Class Codes: H04N 2201/04793 using stored control or compensation data, e.g. previously measured data

Abstract

A document camera (1) detects a figure of a known shape on a stage (13) and acquires the coordinates of the figure, and acquires image processing area and projection correction parameter. The document camera (1) extracts image data of the image processing area from image data acquired by shooting the stage (13) and an original (4), and performs projection correction on the image data using the projection correction parameter. Further, the document camera (1) performs rotation correction on image data undergone projection correction. Furthermore, the document camera (1) performs zoom correction on image data undergone rotation correction, and generates output input image.

Claims

1. An imaging apparatus comprising:

an area acquisition section (203) which acquires an area from which an image is to be extracted, based on an input image including an original (4), placed on a stage (13) including a figure of a known shape and acquired by shooting the stage (13) and the original (4) from an oblique direction, and the figure;

an extraction section (203) which extracts from the input image an image of a portion corresponding to the area acquired by the area acquisition section (203);

a parameter acquisition section (203) which acquires a parameter for correcting the image extracted by the extraction section (203) to an image of the original (4) as seen from the front; and

a correction section (203) which corrects the image extracted by the extraction section (203) to the image of the original (4) as seen from the front using the parameter acquired by the parameter acquisition section (203).

2. The imaging apparatus according to claim 1, wherein the stage (13) comprises a figure of a known shape, and

the area acquisition section (203) acquires an area in the input image which corresponds to the stage (13), to acquire an area from which an image is to be extracted.

3. The imaging apparatus according to claim 1, wherein the figure of the known shape is laid out on a surface of that portion of the stage (13) where the original (4) is to be placed, and

the area acquisition section (203) acquires an area in the input image which corresponds to the figure to acquire an area from which an image is to be extracted.

4. The imaging apparatus according to claim 1, wherein plural marks of known shapes are laid out on a surface of that portion of the stage (13) where the original (4) is to be placed, and

the area acquisition section (203) acquires a figure whose apexes are positions of the plural marks from the input image, further acquires an area in the input image which is occupied by the figure to acquire an area from which an image is to be extracted.

5. The imaging apparatus according to claim 1, wherein the area acquisition section (203) acquires straight lines representing a boundary portion between an area occupied by the stage (13) and an area occupied by the original (4) from the input image, and acquires an area figure to figure to acquire an area occupied by a figure surrounded by the straight lines to acquire an area from which an image is to be extracted.

6. The imaging apparatus according to claim 1, wherein the area acquisition section (203) acquires straight lines representing a boundary portion between an area occupied by the stage (13) and an image area occupied by the original (4) from the input image,

upon acquisition of straight lines representing a boundary portion between the area occupied by the stage (13) and an area occupied by the original (4), acquires an area surrounded by the straight lines or a contour straight line of the stage (13) to acquire an area from which an image is to be extracted, and

when the straight lines representing the boundary portion between the area occupied by the stage (13) and the area occupied by the original (4) are not acquired, acquires an area surrounded by the contour straight line of the stage (13) to acquire an area from which an image is to be extracted.

7. The imaging apparatus according to claim 1, further comprising a storage section (201) which prestores data indicating an area to be acquired by the area acquisition section (203);

and

wherein the area acquisition section (203) reads the data indicating the area from the storage section (201), and acquires an area from which an image is to be extracted.

8. The imaging apparatus according to claim 1, further comprising a parameter memory section (201) which stores a parameter acquired by the parameter acquisition section (203), and

wherein the correction section (203) reads the parameter stored in the parameter memory section (201), and corrects image data extracted by the extraction section (203) to an image of the original (4) as seen from the front using the read parameter.

9. The imaging apparatus us according to claim 1, wherein the extraction section (203) extracts from the input image an image of a portion corresponding to the area acquired by the area acquisition section (203), and further

compresses the extracted image by performing a statistical process on values associated with individual pixels included in each range represented by a set of pixels constituting the extracted image, range by range, and generates an image to be subjected to image processing by the correction section (203).

10. The imaging apparatus according to claim 1, wherein the correction section (203) reads the parameter stored in the parameter memory section (201), and performs image processing of correcting the image extracted by the extraction section (203) to an image of the original (4) as seen from the front using the parameter acquired by the parameter acquisition section (203), and further

compresses the image acquired by image processing by performing a statistical process on values associated with individual pixels included in each range represented by a set of pixels constituting the image acquired by image processing, range by range.

11. The imaging apparatus according to claim 1, further comprising a change acquisition section (203) which computes a change in an image based on a first image to be acquired by shooting the stage (13) including a figure of a known shape, and the original (4) placed on the stage (13) at a first timing, and a second image to be acquired by shooting the stage (13) and the original (4) at a second timing different from the first timing, and

wherein when the change acquired by the change acquisition section (203) is greater than a preacquired threshold, the extraction section (203) compresses the first image by performing a statistical process on values associated with individual pixels included in each range represented by a set of pixels constituting the first image, range by range, and generates an image to be subjected to image processing by the correction section (203).

12. The imaging apparatus according to claim 1, further comprising:

a change acquisition section (203) which computes a change in image data based on a first image to be acquired by shooting the stage (13) including a figure of a known shape, and the original (4) placed on the stage (13) at a first timing, and a second image to be acquired by shooting the stage (13) and the original (4) at a second timing different from the first timing, and

a processing section (203) which compresses the first image by performing a statistical process on values associated with individual pixels included in each range represented by a set of pixels constituting the first image, range by range, when the change acquired by the change acquisition section (203) is greater than a preacquired threshold.

13. The imaging apparatus according to claim 1, further comprising:

a rotation parameter acquisition section (203) which acquires a parameter for rotating an image, obtained through image processing by the correction section (203), on a plane; and

rotation correction section (203) which rotates the image obtained through image processing by the correction section (203) by using the parameter acquired by the rotation parameter acquisition section (203).

14. The imaging apparatus according to claim 1, further comprising:

a zoom parameter acquisition section (207) which acquires a parameter for zooming up or down an image, obtained through image conversion by the correction section (203), on a plane; and

a zoom correction section (207) which zooms up or down the image obtained through image processing by the correction section (203) by using the parameter acquired by the zoom parameter acquisition section (207).

15. The imaging apparatus according to claim 13, further comprising:

a zoom parameter acquisition section (207) which acquires a parameter for zooming up or down an image, obtained through image conversion by the rotation correction section (203), on a plane; and

a zoom correction section (207) which zooms up or down the image obtained by rotation by the rotation correction section (203) by using the parameter acquired by the zoom parameter acquisition section (207).

16. The imaging apparatus according to claim 1, further comprising:

an imaging section (21) which acquires an input image by shooting the stage (13) including a figure of a known shape and the original (4), placed on the stage (13);

a pole brace (12) on which the imaging section (21) is mounted; and

a tilt detection section (205) which detects a change in tilting of the pole brace (12), and

wherein when the change is greater than a preacquired value,

the parameter acquisition section (203) acquires a parameter for correcting the input image to an image as seen from the front, and

the correction section (203) corrects the input image to an image of the original (4) as seen from the front using the parameter extracted by the parameter acquisition section (203).

17. Image processing method for an imaging apparatus comprising:

an area acquisition step (203) of acquiring an area from which an image is to be extracted, based on an input image including an original (4), placed on a stage (13) including a figure of a known shape and acquired by shooting the stage (13) and the original (4) from an oblique direction, and the figure;

an extraction step (203) of extracting from the input image an image of a portion corresponding to the area acquired by the area acquisition step (203);

a parameter acquisition step (203) of acquiring a parameter for correcting the image extracted by the extraction step (203) to an image of the original (4) as seen from the front; and

a correction step (203) of correcting the image extracted by the extraction step (203) to the image of the original (4) as seen from the front using the parameter acquired by the parameter acquisition step (203).

18. A recording medium having recorded a program which allows a computer to execute:

an area acquisition step (203) of acquiring an area from which an image is to be extracted, based on an input image including an original (4), placed on a stage (13) including a figure of a known shape and acquired by shooting the stage (13) and the original (4) from an oblique direction, and the figure;

an extraction step (203) of extracting from the input image an image of a portion corresponding to the area acquired by the area acquisition step (203);

a parameter acquisition step (203) of acquiring a parameter for correcting the image extracted by the extraction step (203) to an image of the original (4) as seen from the front; and

a correction step (203) of correcting the image extracted by the extraction step (203) to the image of the original (4) as seen from the front using the parameter acquired by the parameter acquisition step (203).

19. A carrier wave signal superimposed with a program signal which allows a computer to execute:

an area acquisition step (203) of acquiring an area from which an image is to be extracted, based on an input image including an original (4), placed on a stage (13) including a figure of a known shape and acquired by shooting the stage (13) and the original (4) from an oblique direction, and the figure;

an extraction step (203) of extracting from the input image an image of a portion corresponding to the area acquired by the area acquisition step (203);

a parameter acquisition step (203) of acquiring a parameter for correcting the image extracted by the extraction step (203) to an image of the original (4) as seen from the front; and

a correction step (203) of correcting the image extracted by the extraction step (203) to the image of the original (4) as seen from the front using the parameter acquired by the parameter acquisition step (203).