Image processing method, image signal processor, and image processing system including the same

Patent metadata

Field	Value
Publication number	US-9392236-B2
Application number	US-201314067220-A
Country	US
Kind code	B2
Filing date	Oct 30, 2013
Priority date	Oct 31, 2012
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

An image processing method includes: receiving image data of a Bayer format comprising red color information, green color information, and blue color information, generating image data of a modified Bayer format by combining the green color information with the red color information and combining the green color information with the blue color information while downscaling the image data of the Bayer format to a target resolution, denoising the image data of the modified Bayer format, and generating RGB image data by demosaicing the denoised image data of the modified Bayer format.

First claim

What is claimed is:

1. An image processing method comprising:
receiving image data of a Bayer format comprising red color information for a first pixel, green color information for a second pixel, and blue color information for a third pixel, wherein the second pixel is adjacent to the first and third pixels;
generating image data of a modified Bayer format comprising green-red color information for the first pixel by combining the green color information with the red color information, the green color information of the second pixel, and green-blue color information for the third pixel by combining the green color information with the blue color information, while downscaling the image data of the Bayer format to a target resolution;
denoising the image data of the modified Bayer format; and
generating RGB image data by demosaicing the denoised image data of the modified Bayer format.

2. The image processing method of claim 1 , wherein the generating the image data of the modified Bayer format comprises selectively skipping at least one pixel from the red color information, the green color information, and the blue color information to convert the image data of the Bayer format into the image data of the modified Bayer format.

3. The image processing method of claim 1 , wherein the generating the image data of the modified Bayer format comprises binning the red color information, the green color information, and the blue color information into at least one pixel to convert the image data of the Bayer format into the image data of the modified Bayer format.

4. A non-transitory computer readable recording medium for storing a code for executing the image processing method of claim 1 .

5. The image processing method of claim 1 , wherein the generating of the image data comprises adding the green color information to the red color information to generate the green-red color information, and adding the green color information to the blue color information to generate the green-blue color information.

6. An apparatus for processing image data comprising:
an image signal processor receiving image data of a Bayer format comprising red color information of a first pixel, green color information of a second pixel, and blue color information of a third pixel, converting the image data of the Bayer format into image data of a modified Bayer format comprising green-red color information for the first pixel by combining the green color information with the red color information, the green information of the second pixel, and green-blue color information for a third pixel by combining the green color information with the blue color information while, downscaling the image data of the Bayer format to a target resolution; denoising the image data of the modified Bayer format; and converting the denoised image data of the modified Bayer format into RGB image data, wherein the second pixel is adjacent to the first and third pixels.

7. The apparatus of claim 6 , wherein the image signal processor selectively skips at least one pixel from the image data of the Bayer format to convert the image data of the Bayer format into the image data of the modified Bayer format.

8. The apparatus of claim 6 , wherein the image signal processor bins the image data of the Bayer format into at least one pixel to convert the image data of the Bayer format into the image data of the modified Bayer format.

9. The apparatus of claim 6 , wherein the image signal processor comprises:
a U/V generator configured to convert the denoised image data of the modified Bayer format into a U/V image signal comprising YUV pixel data having the target resolution based on the red color information, the blue color information, and the green color information in a predetermined local area;
a low-pass filter (LPF) interpolator configured to pass and interpolate information only in a low-frequency range of the U/V image signal; and
a transformer configured to combine an output value of the LPF interpolator and the green color information into RGB format data,
wherein the image signal processor is configured to post process the RGB format data to generate the RGB image data.

10. The apparatus of claim 6 , wherein the combining the green color information with the red color information comprises adding the green color information to the red color information to generate the green-red color information and the combining the green color information with the blue color information comprises adding the green color information to the blue color information to generate the green-blue color information.

11. An image processing system comprising:
an image sensor; and
the apparatus of claim 6 .

12. The apparatus of claim 6 , wherein the image signal processor comprises:
a low-pass filter (LPF) interpolator configured to multiply each of pixels in the denoised image data of the modified Bayer format by an LPF coefficient corresponding to each pixel and then interpolate the multiplied image data with the red color information, the blue color information, first green plus color information comprising the green color information added to the red color information, and second green plus color information comprising the green color information added to the blue color information; and
a high-pass filter (HPF),
wherein the image signal processor is configured to output a mean of the first green plus color information and the second green plus color information as green plus color information,
wherein the HPF is configured to pass a high-frequency range of the denoised image data of the modified Bayer format,
wherein the image signal processor is configured to correlate an output value of the HPF and each of the red color information, the green plus color information, and the blue color information and to output red channel information, output green channel information, and output blue channel information,
wherein the image signal processor is configured to post process the output red channel information, the output green channel information, and the output blue channel information and to output the RGB image data.

13. The apparatus of claim 12 , wherein the LPF coefficients are arranged to be symmetric in all directions comprising a horizontal direction, a vertical direction, and a diagonal direction.

14. The apparatus of claim 6 , further comprising a stretcher configured to linearly stretch the image data of the modified Bayer format into stretched image data.

15. The apparatus of claim 14 , wherein the image signal processor denoises the stretched image data into the denoised image data and converts the denoised image data into the RGB image data.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Artyomov Evgeny
• Sfaradi Roee
• Lee Ju Young
• Zinevich Artem
• Voronov German
• Fainstain Eugene

Classifications

• H04N25/134

  based on three different wavelength filter elements · CPC title

• H04N23/843 Primary

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

• H04N23/81

  for suppressing or minimising disturbance in the image signal generation · CPC title

• G06T2207/10024

  Color image · CPC title

• G06T5/70

  Denoising; Smoothing · CPC title