Image processing apparatus and image processing method, and program

Patent metadata

Field	Value
Publication number	US-2016112659-A1
Application number	US-201514982239-A
Country	US
Kind code	A1
Filing date	Dec 29, 2015
Priority date	Jan 24, 2012
Publication date	Apr 21, 2016
Grant date	—

Abstract

An apparatus for and a method of executing noise reduction processing and defect compensation processing on an image in an RGBW arrangement are provided. In pixel value compensation processing of a color pixel that makes up image data in the RGBW arrangement that has each color pixel of R, G, and B and a white (W) pixel, the W pixel is interpolated at a position of an attention pixel that is a compensation target, and at a position of a reference pixel which has the same color as an attention pixel within a reference area, smoothing weight is calculated based on each pixel value of the interpolation W pixel, and thus a compensation pixel value of the attention pixel is calculated by executing smoothing processing to which the calculated smoothing weight is applied. Moreover, by applying the W pixel in the neighborhood of the color pixel, it is determined whether or not the color pixel is in a texture area, and only if the color pixel is not in the texture, defect compensation processing is executed.

First claim

1 . An image processing apparatus comprising:
a signal processing unit that executes pixel value compensation, wherein the signal processing unit inputs image data in an RGBW arrangement that has each color pixel of R, G, and B and a white (W) pixel that passes through almost all wavelength light of each wavelength of the R, G, and B, and wherein the signal processing unit interpolates the W pixel at a position of an attention pixel that is a compensation target, and at a position of a reference pixel which has the same color as the attention pixel within a reference area, in a pixel value compensation processing of a color pixel, calculates smoothing weight based on each pixel value of the interpolation W pixel, and thus calculates a compensation pixel value of the attention pixel by executing smoothing processing to which the calculated smoothing weight is applied.

2 . The image processing apparatus according to claim 1 ,
wherein the signal processing unit determines whether or not one or more saturation pixel values are present in the pixel values of the interpolation W pixel, wherein if the saturation pixel value is not present in the pixel values of the interpolation W pixel, the signal processing unit calculates a compensation pixel value of the attention pixel by executing the smoothing processing to which the smoothing weight, calculated based on the each pixel value of the interpolation W pixel, is applied, and wherein if the saturation pixel value is present in the pixel values of the interpolation W pixel, the signal processing unit calculates the compensation pixel value of the attention pixel by executing the smoothing processing to which the smoothing weight, calculated based on each pixel value of the attention pixel that is the compensation target, and of the reference pixel which has the same color as the attention pixel within the reference area, is applied without applying the interpolation W pixel.

3 . The image processing apparatus according to claim 1 ,
wherein the signal processing unit executes processing that interpolates the W pixel at the position of the reference pixel which has the same color as the attention pixel present in the reference area that is a two-dimensional area with the reference area as the two-dimensional area.

4 . The image processing apparatus according to claim 1 ,
wherein the signal processing unit executes processing that interpolates the W pixel at the position of the reference pixel which has the same color as the attention pixel present in the reference area that is a one-dimensional area with the reference area as the one-dimensional area.

5 . The image processing apparatus according to claim 1 ,
wherein the signal processing unit executes the pixel value compensation as noise reduction (NR) processing that reduces noise that is included in the attention pixel.

6 . The image processing apparatus according to claim 1 ,
wherein the signal processing unit determines a likelihood of a defect, that is, determines whether or not there is a likelihood that the color pixel will be a defective pixel, wherein the signal processing unit executes texture detection processing that determines whether or not the color pixel is in a texture area, by applying the W pixel in the neighborhood of the color pixel that is determined as having the likelihood of the defect, wherein in the texture detection processing, if it is determined that the color pixel is in the texture area, the signal processing unit does not execute defect compensation processing, and wherein in the texture detection processing, if it is determined that the color pixel is not in the texture area, the signal processing unit executes the defect compensation processing.

7 . The image processing apparatus according to claim 6 ,
wherein in the texture detection processing, the signal processing unit determines whether or not the color pixel is in the texture area, by applying a difference in the pixel value between the W pixel that is closest to the color pixel that is determined as having the likelihood of the defect, and the W pixel outside of the closest W pixel.

8 . An image processing method of executing pixel value compensation in an image processing device, wherein a signal processing unit of the image processing device performs:
inputting image data in an RGBW arrangement that has each color pixel of R, G, and B and a white (W) pixel that passes through almost all wavelength light of each wavelength of the R, G, and B; interpolating the W pixel at a position of an attention pixel that is a compensation target, and at a position of a reference pixel which has the same color as the attention pixel within a reference area, in a pixel value compensation processing of a color pixel; calculating smoothing weight based on each pixel value of the interpolation W pixel; and calculating a compensation pixel value of the attention pixel by executing smoothing processing to which the calculated smoothing weight is applied.

9 . A program for executing pixel value compensation in an image processing apparatus, which causes a signal processing unit of the image processing apparatus to perform:
inputting image data in an RGBW arrangement that has each color pixel of R, G, and B and a white (W) pixel that passes through almost all wavelength light of each wavelength of the R, G, and B; interpolating the W pixel at a position of an attention pixel that is a compensation target, and at a position of a reference pixel which has the same color as the attention pixel within a reference area, in a pixel value compensation processing of a color pixel; calculating smoothing weight based on each pixel value of the interpolation W pixel; and calculating a compensation pixel value of the attention pixel by executing smoothing processing to which the calculated smoothing weight is applied.

Assignees

• Sony Corp

Inventors

• Tachi Masayuki

Classifications

• G06T3/4015 Primary

  Image demosaicing, e.g. colour filter arrays [CFA] or Bayer patterns · CPC title

• H04N2209/042

  having a single pick-up sensor · CPC title

• H04N2209/046

  Colour interpolation to calculate the missing colour values · CPC title

• H04N9/646

  for image enhancement, e.g. vertical detail restoration, cross-colour elimination, contour correction, chrominance trapping filters · CPC title

• H04N23/843

  Demosaicing, e.g. interpolating colour pixel values · CPC title