Image processing apparatus and method for image processing

Patent metadata

Field	Value
Publication number	US-9635286-B2
Application number	US-201514923584-A
Country	US
Kind code	B2
Filing date	Oct 27, 2015
Priority date	Nov 6, 2014
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

There is provided an image processing apparatus including imaging elements, including: a selection unit configured to select any one of the first image and the second image as a selected image based on a first pixel included in the first image and a second pixel included in the second image, wherein the first pixel and the second pixel respectively belong to a duplicated area, the duplicated area being an area of a captured object overlapping in respective images; a calculation unit configured to calculate a correction coefficient for correcting a pixel before correction based on a selected pixel and the pixel before correction, a correction unit configured to correct the pixel before correction based on the correction coefficient to generate an image after correction; and an image generation unit configured to generate an output image based on the selected image and the image after correction.

First claim

What is claimed is:

1. An image processing apparatus including a first imaging element for capturing a first image and a second imaging element for capturing a second image, the image processing apparatus comprising:
a memory;
and a processor that executes a program to implement the following:
a selection unit configured to select any one of the first image and the second image as a selected image by calculating a first average of the pixels included in a first selected block indicating an average brightness of first pixels included in the first image and a second average of the pixels included in a second selected block indicating an average brightness of second pixels included in the second image, and comparing the first average with the second average to determine a smaller one of the first average and the second average to be a smaller average, thereby selecting the one of the first image and the second image with which the smaller average is associated to be the selected image, wherein the first pixels and the second pixels respectively belong to a duplicated area, the duplicated area being an area of a captured object overlapping in respective images captured by the first imaging element and the second imaging element,
and wherein the duplicated area is divided to generate evaluation blocks having the same size,
and the selected block is a block selected from the respective evaluation blocks;
and the selection unit is further configured to set the selected blocks for excluding a range in the area of the image;
a calculation unit configured to calculate a correction coefficient for correcting a pixel before correction based on a selected pixel and the pixel before correction, wherein the selected pixel is included in the selected image and the pixel before correction is included in an image before correction, the image before correction being one of the first image and the second image, which is not selected as the selected image;
a correction unit configured to correct the pixel before correction based on the correction coefficient to generate an image after correction;
and an image generation unit configured to generate an image to be output based on the selected image and the image after correction.

2. The image processing apparatus as claimed in claim 1 , wherein execution of the program causes the processor to further implement the following:
a determination unit configured to determine whether the pixel before correction corresponds to a light source captured in the first image or second image, wherein
the correction unit prevents the pixel before correction, which is determined to correspond to the light source captured in the first image or second image, from being corrected.

3. The image processing apparatus as claimed in claim 1 , wherein
the calculation unit calculates a first correction coefficient by dividing a pixel value of the selected pixel by a pixel value of the pixel before correction,
the calculation unit calculates a pixel value of a pixel after correction included in the image after correction by multiplying the pixel value of the pixel before correction by the first correction coefficient,
the calculation unit calculates a second correction coefficient based on the pixel value of the pixel after correction and a pixel value of a pixel located around a center of the image before correction, and
the correction unit multiplies the pixel value of the pixel before correction by the first correction coefficient or the second correction coefficient to correct the pixel before correction.

4. The image processing apparatus as claimed in claim 3 , wherein
the calculation unit sets at least one of an upper limit value of the correction coefficient or a lower limit value of the correction coefficient.

5. The image processing apparatus as claimed in claim 1 , further comprising a third imaging element for capturing a third image, wherein
the selection unit is configured to select any one of the captured images as a selected image by calculating a first average of the pixels included in a first selected block indicating an average brightness of first pixels included in the first image, a second average of the pixels included in a second selected block indicating an average brightness of second pixels included in the second image, and a third average of the pixels included in a third selected block indicating an average brightness of third pixels included in the third image, and comparing the first average with the second and third averages to determine a smaller one of the first average, the second average, and the third average to be a smaller average, thereby selecting the one of the first image, the second image, and the third image with which the smallest average is associated to be the selected image, wherein the pixels respectively belong to a duplicated area, the duplicated area being an area of a captured object overlapping in respective images captured by the three or more imaging elements,
the image before correction being one of the captured images, which is not selected as the selected image.

6. A method for image processing performed by an image processing apparatus including a first imaging element for capturing a first image and a second imaging element for capturing a second image, the method comprising:
selecting any one of the first image and the second image as a selected image by calculating a first average of the pixels included in a first selected block indicating an average brightness of first pixels included in the first image and a second average of the pixels included in a second selected block indicating an average brightness of second pixels included in the second image, and comparing the first average with the second average to determine a smaller one of the first average and the second average to be a smaller average, thereby selecting the one of the first image and second image with which the smaller average is associated to be the selected image, wherein the first pixels and the second pixels respectively belong to a duplicated area, the duplicated area being an area of a captured object overlapping in respective images captured by the first imaging element and the second imaging element, and wherein
the duplicated area is divided to generate evaluation blocks having the same size, and
the selected block is a block selected from the respective evaluation blocks; and
the selected blocks are set for excluding a range in the area of the image;

calculating a correction coefficient for correcting a pixel before correction based on a selected pixel and the pixel before correction, wherein the selected pixel is included in the selected image and the pixel before correction is included in an image before correction, the image before correction being one of the first image and the second image, which is not selected as the selected image;
correcting the pixel before correction based on the correction coefficient to generate an image after correction; and
generating an image to be output based on the selected image and the image after correction.

Assignees

• Yoshikawa Hiromi
• Ricoh Co Ltd

Inventors

• Yoshikawa Hiromi

Classifications

• G03B37/04 Primary

  with cameras or projectors providing touching or overlapping fields of view · CPC title

• H04N25/41

  Extracting pixel data from a plurality of image sensors simultaneously picking up an image, e.g. for increasing the field of view by combining the outputs of a plurality of sensors · CPC title

• H04N23/698

  for achieving an enlarged field of view, e.g. panoramic image capture · CPC title

• H04N23/45

  for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images · CPC title

• G06F18/22

  Matching criteria, e.g. proximity measures · CPC title