Image Processing Device Frequency Band Segmentation for Artifact-Free Enhancement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image processing methods fail to adequately enhance images that include fold-over components on the high-frequency side of their frequency spectrum or lack sufficient high-frequency components, leading to inappropriate or inadequate enhancement processing and potential artifacts.
Innovation Solution
An image processing apparatus and method that generate and add high-frequency components to an input image by extracting specific frequency bands using band-pass filters and performing non-linear processing to enhance the image, while preventing overshoot and artifacts, without increasing circuit size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If high-frequency enhancement processing is applied to an enlarged image, then perceived resolution is improved, but fold-over components are enhanced causing artifacts
Solution Approach 1:
The frequency spectrum is segmented into multiple bands using band-pass filters. The enhancement processing is applied selectively to specific frequency bands (first and second frequency bands) while excluding other bands where fold-over components reside. This segmentation allows the system to enhance perceived resolution by boosting appropriate high-frequency components without enhancing harmful fold-over artifacts.
2Object-generated harmful factors
If the frequency band is limited to exclude fold-over components, then artifacts are reduced, but high-frequency enhancement becomes inadequate
Solution Approach 1:
Different frequency bands are treated with different enhancement strategies. The system applies enhancement processing to specific frequency bands (first and second bands) that contain useful high-frequency information, while deliberately excluding bands containing fold-over components. This local quality approach ensures that enhancement is applied where beneficial and avoided where harmful, resolving the contradiction between adequate enhancement and artifact reduction.
3Object-affected harmful factors
If noise suppression is applied to the input image, then noise is reduced, but high-frequency components are eliminated making enhancement impossible
Solution Approach 1:
The system performs frequency band extraction and selective enhancement before final image output. By identifying and extracting useful high-frequency components in specific frequency bands prior to enhancement, the system ensures that these components are preserved and enhanced even if noise suppression processing has been applied to the input image. The preliminary extraction action protects the high-frequency information from being completely eliminated by noise suppression.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
An intermediate image generating means (1) generates a horizontal intermediate image (D1h) and a vertical intermediate image (D1v) by extracting components of an input image (DIN) in a particular frequency band; an intermediate image processing means (2) generates a horizontal image (D2Bh) and a vertical image (D2Bv) by performing non-linear processing (2A) and high-frequency component generation (2B) ; an intermediate image (D2) is obtained by combining these horizontal and vertical images by performing weighted addition for each pixel and is added (3) to the input image (DIN) to obtain an enhanced output image (DOUT). Even if the input image includes a fold-over component on the high-frequency side or does not include an adequate high-frequency component, adequate image enhancement processing can be carried out.