Image processing apparatus and method

Patent metadata

Field	Value
Publication number	US-2016284056-A1
Application number	US-201514840032-A
Country	US
Kind code	A1
Filing date	Aug 30, 2015
Priority date	Mar 25, 2015
Publication date	Sep 29, 2016
Grant date	—

Abstract

An image processing apparatus includes a high-frequency component translating unit, a high-frequency component extracting unit, a detail-gain generating unit and an image output unit. The high-frequency component translating unit extracts and translates first high-frequency components of an input image to generate a first image. The high-frequency component extracting unit extracts second high-frequency components to generate a second image. The detail-gain generating unit stores a conversion table and generates detail gains respectively associated with input pixels in the input image according to pixel values of the input pixels and the conversion table. The image output unit calculates a weighted superposition of the first image and the second image and generates a high frequency component of an output image according to the weighted superposition and the detail gains.

First claim

What is claimed is:

1 . An image processing apparatus, comprising:
a high-frequency component translating unit configured to extract and translate a plurality of first high-frequency components of an input image to generate a first image; a high-frequency component extracting unit configured to extract a plurality of second high-frequency components of the input image to generate a second image; a detail-gain generating unit configured to store a conversion table and generate a plurality of detail gains respectively associated with a plurality of input pixels in the input image according to the conversion table and pixel values of the input pixels; and an image output unit configured to calculate a weighted superposition of the first image and the second image and to generate a high-frequency component of an output image according to the detail gains and the weighted superposition.

2 . The image apparatus of claim 1 , wherein the image output unit is configured to blend the high-frequency component of the output image into the input image to generate the output image.

3 . The image apparatus of claim 1 , wherein the detail-gain generating unit is configured to extract a plurality of neighboring pixels separate from a first input pixel by at least one pixel and to search the conversion table with a pixel value sum of the first input pixel and the neighboring pixels to generate one of the detail gains associated with the first input pixel, wherein the first input pixel is one of the input pixels.

4 . The image apparatus of claim 3 , wherein the detail-gain generating unit is configured to extract pixels separate from the first input pixel by one pixel from up, down, left, and right directions as the neighboring pixels.

5 . The image apparatus of claim 1 , wherein the conversion table stored in the detail gain generating unit corresponds to a periodic continuous function.

6 . The image apparatus of claim 1 , wherein a value range of the detail gains is from 0 to N.

7 . The image apparatus of claim 1 , wherein the high-frequency component translating unit comprises at least two overshoot high-pass filters configured to filter the input image to generate a plurality of high-frequency translation images, and the high-frequency component translating unit is configured to generate the first image by selecting pixels with highest absolute pixel values from the high-frequency translation images, and the high-frequency translation images comprise the first high-frequency components, respectively.

8 . The image apparatus of claim 7 , wherein the overshoot high-pass filters are associated with a plurality of masks respectively, and coefficient values at the center and periphery of the masks are positive while the rest of the coefficient values of the masks are negative.

9 . The image apparatus of claim 1 , wherein the high-frequency component extracting unit comprises at least two high-pass filters configured to filter the input image to generate a plurality of high-frequency images and is configured to generate the second image by selecting pixels with highest absolute pixel values from the high-frequency images, and the high-frequency images comprise the second high-frequency components, respectively.

10 . An image processing method, comprising:
extracting and translating a plurality of first high-frequency components from an input image to generate a first image; extracting a plurality of second high-frequency components from the input image to generate a second image; generating a plurality of detail gains respectively associated with a plurality of input pixels in the input image according to pixel values of the input pixels and a conversion table; and calculating a weighted superposition of the first image and the second image and generating a high-frequency component of an output image according to the detail gains and the weighted superposition.

11 . The image processing method of claim 10 , further comprising:
blending the high-frequency component of the output image into the input image to generate the output image.

12 . The image processing method of claim 10 , wherein the operation of generating the detail gains comprises:
extracting a plurality of neighboring pixels separate from a first input pixel by at least one pixel, and searching the conversion table with a pixel value sum of the first input pixel and the neighboring pixels to generate one of the detail gains associated with the first input pixel, wherein the first input pixel is one of the input pixels.

13 . The image processing method of claim 12 , wherein the operation of generating the detail gains comprises:
extracting pixels separate from the first input pixel by one pixel from up, down, left, and right directions as the neighboring pixels.

14 . The image processing method of claim 10 , wherein the conversion table corresponds to a periodic continuous function.

15 . The image processing method of claim 10 , wherein a value range of the detail gains is from 0 to N.

16 . The image processing method of claim 10 , wherein the operation of generating the first image comprises:
filtering the input image to generate a plurality of high-frequency translation images with at least two overshoot high-pass filters, and generating the first image by selecting pixels with highest absolute pixel values from the high-frequency translation images, wherein the high-frequency translation images comprise the first high-frequency components, respectively.

17 . The image processing method of claim 16 , wherein the overshoot high-pass filters are associated with a plurality of masks respectively, and coefficient values at the center and periphery of the masks are positive while the rest of the coefficient values of the masks are negative.

18 . The image processing method of claim 10 , wherein the operation of generating the second image comprises:
filtering the input image to generate a plurality of high-frequency images with at least two high-pass filters, and generating the second image by selecting pixels with highest absolute pixel values from the high-frequency images, wherein the high-frequency images comprise the second high-frequency components, respectively.

Assignees

• Realtek Semiconductor Corp

Inventors

• Chen Cheng-Yueh
• Hsieh Chun-Hsing
• Yang Jun-Yu
• Sun Zhi-Gang

Classifications

• G06T5/50

  using two or more images, e.g. averaging or subtraction · CPC title

• G06T3/4061 Primary

  by injecting details from different spectral ranges · CPC title

• G06T2207/20221

  Image fusion; Image merging · CPC title

• G06T5/73

  Deblurring; Sharpening · CPC title