IMAGE PROCESSING METHOD AND APPARATUS

• US 20080137980A1
• Filed: 11/27/2007
• Published: 06/12/2008
• Est. Priority Date: 12/06/2006
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Mizuno, Hiroyuki
• Granted Patent: US 8,320,703 B2
• Time in Patent Office: Days
• US Class Current: 382/255
• 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

Abstract

An image processing method executes image processing to correct a non-uniform perceived resolution caused by image distortion correction, thereby achieving a uniform perceived resolution over an entire displayed image. The image processing method includes the step of adjusting an aperture compensation signal using distortion correcting data to correct a non-uniform perceived resolution caused in an image through partial conversion of magnification ratio by image distortion correction, thereby achieving a uniform perceived resolution.

Claims

1. An image processing method of executing image processing to correct a non-uniform perceived resolution caused by image distortion correction, thereby achieving a uniform perceived resolution over an entire displayed image, the image processing method comprising the step of:

adjusting an aperture compensation signal using distortion correcting data to correct a non-uniform perceived resolution caused in an image through partial conversion of magnification ratio by image distortion correction, thereby achieving a uniform perceived resolution.

2. An image processing method of executing image processing on an image obtained through image distortion correction to correct a non-uniform perceived resolution caused by the image distortion correction, thereby achieving a uniform perceived resolution over an entire displayed image, the image processing method comprising the step of:

calculating a suitable gain using distortion correcting data, and compensating for an aperture compensation signal lost by image distortion correction, thereby achieving a uniform perceived resolution over an entire displayed image.

3. An image processing method of executing image processing on an image prior to image distortion correction to correct a non-uniform perceived resolution caused by the image distortion correction, thereby achieving a uniform perceived resolution over an entire displayed image, the image processing method comprising the step of:

shifting a frequency band in which an aperture compensation signal is added, according to an amount of distortion correction for current coordinate values, the amount of distortion correction being determined from distortion correcting data, thereby achieving a uniform perceived resolution over an entire displayed image.

4. An image processing apparatus for executing image processing according to distortion correcting data to correct a non-uniform perceived resolution caused by image distortion correction, thereby achieving a uniform perceived resolution over an entire displayed image, the image processing apparatus comprising:

aperture-compensation-signal adding means for adding a variable-frequency-band aperture compensation signal to a mainline signal at a stage previous to image distortion correction, the variable-frequency-band aperture compensation signal corresponding to a frequency band in which an aperture compensation signal is lost by the image distortion correction; and

step-valued aperture-compensation-gain adjusting means for executing image processing on an image at a stage subsequent to the image distortion correction, using an aperture compensation signal generated on the basis of a step-valued aperture compensation gain calculated using distortion correcting data used in the image distortion correction.

5. The image processing apparatus according to claim 4,

wherein the aperture-compensation-signal adding means calculates coefficients for shifting the frequency band of the aperture compensation signal on the basis of the distortion correcting data used in the image distortion correction, and

wherein the step-valued aperture-compensation-gain adjusting means calculates a step-valued aperture compensation gain using the distortion correcting data used in the image distortion correction, multiplies the step-valued aperture compensation gain by an aperture compensation signal generated from an image obtained through the image distortion correction, and adds the aperture compensation signal multiplied by the step-valued aperture compensation gain to the mainline signal.

6. An image processing apparatus for executing image processing according to distortion correcting data to correct a non-uniform perceived resolution caused by image distortion correction, thereby achieving a uniform perceived resolution over an entire displayed image, the image processing apparatus comprising:

an aperture-compensation-signal adder configured to add a variable-frequency-band aperture compensation signal to a mainline signal at a stage previous to image distortion correction, the variable-frequency-band aperture compensation signal corresponding to a frequency band in which an aperture compensation signal is lost by the image distortion correction; and

a step-valued aperture-compensation-gain adjusting unit configured to execute image processing on an image at a stage subsequent to the image distortion correction, using an aperture compensation signal generated on the basis of a step-valued aperture compensation gain calculated using distortion correcting data used in the image distortion correction.