System and method for removal of digital image vertical distortion

• US 6,963,365 B2
• Filed: 02/28/2001
• Issued: 11/08/2005
• Est. Priority Date: 02/28/2001
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Baron, John M.
• Primary Examiner(s): Garber, Wendy R.
• Assistant Examiner(s): Whipkey, Jason
• Application Number:
  US09/795,598
• Publication Number:
  US 20020118292A1
• Time in Patent Office: 1,714 Days
• Field of Search: 345/647, 348/239
• US Class Current: 348/239
• CPC Class Codes: H04N 23/58 Means for changing the camera field of view without moving the camera body, e.g. nutating or panning of optics or image sensors
• CPC Class Codes: H04N 23/633 for displaying additional information relating to control or operation of the camera
• CPC Class Codes: H04N 23/695 Control of camera direction for changing a field of view, e.g. pan, tilt or based on tracking of objects
• CPC Class Codes: H04N 5/2628 Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation

Abstract

A device, preferably a digital camera, has an imaging sensor providing a digital representation of an image projected onto an imaging portion of the imaging sensor. A processor associated with the device identifies an image compression factor and progressively, over a selected region of the digital representation of the image, magnifies at least a portion of the digital representation of the image to reduce an apparent convergence distortion. Correction preferably occurs before lossy compression. The device preferably includes a display to provide a visual display of the digital representation of the image to a user who may use a user input to manually correct apparent distortion by following prompts generated on the display. The device also preferably includes a non-volatile memory configured to store the digital representation of the image.

Claims

1. A digital camera comprising:

an image sensor providing a digital representation of an optical image to be captured; and

a processor configured to selectively process said digital representation of said optical image to compensate for a linear convergence distortion of said optical image; and

wherein said processor is configured to progressively magnify, in two-dimensions, said digital representation so as to reduce apparent linear convergence, wherein said processor is configured to determine a linear distortion value relative to a baseline, and wherein said processor is configured to determine said linear distortion value in response to identification of an offset from vertical of a line segment identified in said optical image.

2. The digital camera according to claim 1 wherein said processor is configured to apply a varying magnification factor to said digital representation of said optical image along a first axis with respect to a second axis orthogonal to said first axis.

3. The digital camera according to claim 2 wherein said first and second axes correspond to a plane defined by an imaging surface of said image sensor on which said optical image is formed.

4. The digital camera according to claim 2 further comprising:

an input device configured to provide manual control of said magnification factor.

5. The digital camera according to claim 4 further comprising:

a display for displaying said optical image before and after processing by said processor.

6. The digital camera according to claim 1 wherein said processor is configured to apply a variable aspect ratio to said optical image to compensate for said linear convergence distortion of said optical image as formed on said image sensor.

7. The digital camera according to claim 6 wherein said linear distortion is caused by an orientation of an imaging surface of said image sensor with respect to a subject corresponding to at least a portion of said optical image.

8. A digital camera comprising:

an image sensor providing a digital representation of an optical image to be captured; and

a processor configured to selectively process said digital representation of said optical image to compensate for a linear convergence distortion of said optical image; and

wherein said processor is configured to progressively magnify, in two-dimensions, said digital representation so as to reduce apparent linear convergence, wherein said processor is configured to determine a linear distortion value relative to a baseline, and wherein said processor is configured to determine said linear distortion value in response to identification of a difference in length between two line segments identified in said optical image.

9. The digital camera according to claim 8 wherein said processor is configured to apply a varying magnification factor to said digital representation of said optical image along a first axis with respect to a second axis orthogonal to said first axis.

10. The digital camera according to claim 9 wherein said first and second axes correspond to a plane defined by an imaging surface of said image sensor on which said optical image is formed.

11. The digital camera according to claim 9 further comprising:

an input device configured to provide manual control of said magnification factor.

12. The digital camera according to claim 11 further comprising:

a display for displaying said optical image before and after processing by said processor.

13. The digital camera according to claim 8 wherein said processor is configured to apply a variable aspect ratio to said optical image to compensate for said linear convergence distortion of said optical image as formed on said image sensor.

14. The digital camera according to claim 13 wherein said linear distortion is caused by an orientation of an imaging surface of said image sensor with respect to a subject corresponding to at least a portion of said optical image.