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Adaptive Unsharp Masking using Bilateral Filter

Bilateral Filter를 이용한 적응적 언샤프 마스킹

  • Received : 2012.04.27
  • Published : 2012.11.25

Abstract

In this paper, adaptive unsharp masking using bilateral filter, edge-preserving smoothing filter is proposed to reduce the overshoot and jagging artifact in sharpening images. Previous image enhancement methods including unsharp masking(UM) can emphasize high-frequency details strongly, but often cause several artifacts such as overshooting, noise, jagging and so on. Proposed image enhancement method preserves edges well because of using bilateral filter and sensitively controls a weight according to edge's directions. Therefore, it enhances sharpness and effectively reduces overshoot and jagging artifacts. Simulation results comparing output of previous AUM with proposed method show that proposed algorithm makes images properly enhanced, and we know that overshoot and jagging artifacts are many reduced.

본 논문에서는 선명도가 향상된 영상의 오버슈트와 계단현상을 줄이기 위해 에지 보존 스무딩 필터인 bilateral filter를 이용한 적응적 언샤프 마스킹 기법을 제안한다. Unsharp masking(UM)을 포함한 기존의 선명도 개선 기법들은 영상의 고주파정보를 강하게 강조하지만, 종종 오버슈트, 잡음증폭, 계단현상 등 여러 문제점들을 야기한다. 제안한 선명도 개선 방법은 bilateral filter를 활용하여 에지를 잘 보존하고, 에지의 방향성에 따라 가중치를 더 세밀하게 조절한다. 따라서 선명도는 향상시키고 오버슈트, 계단현상 문제를 효과적으로 줄일 수 있었다. 기존의 적응적 언샤프 마스킹 기법과 제안하는 방법의 결과영상을 비교하여 실험을 수행한 결과, 제안하는 알고리즘이 적절하게 선명도를 개선함을 보여주었고 오버슈트와 계단현상도 많이 감소시킴을 알 수 있었다.

Keywords

References

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