Image processing apparatus, image capture apparatus with the same, and method for controlling image processing apparatus to avoid partial loss of an output image by applying geometric deformation to an image

Patent metadata

Field	Value
Publication number	US-9277128-B2
Application number	US-201314132337-A
Country	US
Kind code	B2
Filing date	Dec 18, 2013
Priority date	Dec 25, 2012
Publication date	Mar 1, 2016
Grant date	Mar 1, 2016

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.

First claim

What is claimed is:

1. An image processing apparatus for correcting image quality degradation, comprising a processor configured to function as:
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,
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 plurality of 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.

2. The image processing apparatus according to claim 1 , fur the processor further configured to function as:
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.

3. The image processing apparatus according to claim 2 ,
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.

4. 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.

5. An image capture apparatus comprising:
a sensor that detects motion of the image capture apparatus; and
an image processing apparatus for correcting image quality degradation, comprising a processor configured to function as:
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,
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 plurality of 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,
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.

6. A method for controlling an image processing apparatus that corrects image quality degradation, comprising a processor configured to perform:
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,
wherein:
the deformation process is a combination of a plurality of geometric deformation processes,
in the generating step, a plurality of parameters defining the plurality of geometric deformation processes are generated,
in the determining step, the determination is performed 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
in the adjusting step, the plurality of parameters that are generated in the generating step are adjusted 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.

7. A non-transitory computer-readable recording medium storing a program for causing a computer to function as 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,
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,

Assignees

• Canon Kk

Inventors

• Narita Yu

Classifications

• H04N23/683

  performed by a processor, e.g. controlling the readout of an image memory · CPC title

• H04N23/6812

  based on additional sensors, e.g. acceleration sensors · CPC title

• H04N23/681 Primary

  Motion detection · CPC title

• H04N5/23251 Primary

  Electricity · mapped topic

• H04N5/23267

  Electricity · mapped topic