IMAGE PROCESSING APPARATUS, IMAGE CAPTURE APPARATUS PROVIDED WITH THE SAME, AND METHOD FOR CONTROLLING IMAGE PROCESSING APPARATUS

• US 20140176755A1
• Filed: 12/18/2013
• Published: 06/26/2014
• Est. Priority Date: 12/25/2012
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Narita, Yu
• Granted Patent: US 9,277,128 B2
• Time in Patent Office: Days
• US Class Current: 348/222.1
• CPC Class Codes: G06T 5/80 Geometric correction
• CPC Class Codes: H04N 23/681 Motion detection
• CPC Class Codes: H04N 23/6812 based on additional sensors, e.g. acceleration sensors
• CPC Class Codes: H04N 23/683 performed by a processor, e.g. controlling the readout of an image memory

Abstract

Disclosed in an image processing apparatus capable of avoiding partial loss of an output image due to a lack of reference pixels, when generating an output image by applying geometric deformation to an image. The image processing apparatus determines whether a reference area required in a geometric deformation process fits within a captured area, and, in the case where the reference area required in the geometric deformation process does not fit within the captured area, sets an upper limit for a displacement amount of the reference area of the geometric deformation process so that the reference area fits, and applies the geometric deformation process, which uses a geometric deformation parameter generated based on the set upper limit, to the image.

Claims

1. An image processing apparatus for correcting image quality degradation, comprising:

a generating unit that generates a parameter defining a deformation process for correcting the image quality degradation;

a determining unit that determines whether a reference area, which is an image area required by the deformation process, fits within a captured area that contains the image and is larger than the image;

an adjusting unit that adjusts the parameter such that the reference area fits within the captured area, in a case where it is determined by the determining unit that the reference area does not fit within the captured area; and

a deforming unit that applies the deformation process to the image in accordance with the parameter.

2. The image processing apparatus according to claim 1,

wherein the deformation process is a combination of a plurality of geometric deformation processes,

the generating unit generates a plurality of parameters defining the plurality of geometric deformation processes,

the determining unit performs the determination based on a sum total of displacement amounts, in each of the plurality of geometric deformation processes, before and after the geometric deformation process is applied, and a positional relationship of the captured area and the image, and

the adjusting unit adjusts the parameters that are generated by the generating unit, by setting, for each of the plurality of geometric deformation processes, an upper limit for a displacement amount before and after the geometric deformation process is applied, such that the sum total of displacement amounts is a value in a range in which the reference area fits within the captured area.

3. The image processing apparatus according to claim 2, further comprising:

a setting unit that sets a priority for each of the plurality of geometric deformation processes, based on at least one of information about a main subject of the image and information indicating a shooting condition,

wherein the adjusting unit sets a higher upper limit for a displacement amount the higher the priority of the corresponding geometric deformation process.

4. The image processing apparatus according to claim 3,

wherein the main subject information is any of a likelihood of the main subject being human, a size of the main subject and a distance to the main subject, and the information indicating the shooting condition is a shutter speed and a subject brightness value.

5. The image processing apparatus according to claim 1,

wherein the deformation process is one or more of:

resizing and clipping of an image,

a projective transform for correcting tilt and rotation of an image,

rolling shutter distortion correction for correcting rolling shutter distortion produced by shooting with an image sensor that employs a rolling shutter, and

distortion aberration correction for correcting distortion aberration caused by optical characteristics of a lens.

6. An image capture apparatus comprising:

a detection unit that detects motion of the image capture apparatus; and

the image processing apparatus according to claim 1,

wherein the image processing apparatus corrects image quality degradation that has occurred in an image due to motion of the image capture apparatus and outputs the corrected image.

8. A non-transitory computer-readable recording medium storing a program for causing a computer to function as the image processing apparatus according to claim 1.

7. A method for controlling an image processing apparatus that corrects image quality degradation, comprising:

a generating step of generating a parameter defining a deformation process for correcting the image quality degradation;

a determining step of determining whether a reference area, which is an image area required by the deformation process, fits within a captured area that contains the image and is larger than the image;

an adjusting step of adjusting the parameter such that the reference area fits within the captured area, in a case where it is determined in the determining step that the reference area does not fit within the captured area; and

a deforming step of applying the deformation process to the image in accordance with the parameter.