• 융합신호처리학회논문지
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• 제14권1호
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• pp.6-12
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• 2013

맘모그램은 유방암의 조기발견을 위해 가장 일반적으로 이용되고 있다 유방암의 정확한 진단과 효율적인 치료를 위하여 많은 영상향상 방법들이 개발되어왔다. 본 논문은 디지털 유방 촬영상의 영상향상을 위하여 새로운 비선형 영상향상 방법을 제안한다. 제안된 방법은 영상의 밝기 정보를 향상시키기 위한 비선형 함수와 경계와 디테일 정보를 개선하기 위한 비선형 필터로 구성된다. 비선형 함수는 영상의 어두운 영역의 밝기를 향상시키고 밝은 영역의 동적범위를 넓혀주며, 비선형 필터는 영상의 특정 영역이나 객체를 효과적으로 개선시킨다. 최종 향상된 영상은 비선형 함수로 처리한 영상과 비선형 필터로 필터된 영상을 더하여 얻어진다. 제안된 비선형 영상향상 방법은 실험에서 기존 방법과 영상향상 결과를 비교하여 우수한 성능을 확인하였다.

• 한국해양공학회지
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• 제34권6호
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• pp.442-453
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• 2020

Underwater color images suffer from low visibility and color cast effects caused by light attenuation by water and floating particles. This study applied single image enhancement techniques to enhance the quality of underwater images and compared their performance with real underwater images taken in Korean waters. Dark channel prior (DCP), gradient transform, image fusion, and generative adversarial networks (GAN), such as cycleGAN and underwater GAN (UGAN), were considered for single image enhancement. Their performance was evaluated in terms of underwater image quality measure, underwater color image quality evaluation, gray-world assumption, and blur metric. The DCP saturated the underwater images to a specific greenish or bluish color tone and reduced the brightness of the background signal. The gradient transform method with two transmission maps were sensitive to the light source and highlighted the region exposed to light. Although image fusion enabled reasonable color correction, the object details were lost due to the last fusion step. CycleGAN corrected overall color tone relatively well but generated artifacts in the background. UGAN showed good visual quality and obtained the highest scores against all figures of merit (FOMs) by compensating for the colors and visibility compared to the other single enhancement methods.

• 대한음성학회지:말소리
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• 제48호
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• pp.81-91
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• 2003

In this paper, we propose a speech recognition method based on independent component analysis (ICA) and spectral enhancement techniques. While ICA tris to separate speech signal from noisy speech using multiple channels, some noise remains by its algorithmic limitations. Spectral enhancement techniques can compensate for lack of ICA's signal separation ability. From the speech recognition experiments with instantaneous and convolved mixing environments, we show that the proposed approach gives much improved recognition accuracies than conventional methods.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.514-517
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• 1998

This paper proposed a symmetric feedback current enhancement circuit with 1.5V power supply to design a 3$^{rd}$ order butterworth low pass filter. The proposed filter designed on 0.8.mu.m CMOS n-well double poly/double metal process simulated in HSPICE composed of the 3dB frequency enhancement circuit and the unity-gain frequency enhancement circuit. The simulation result on the design filter shows the badnwith of 25MHz, phase of 92.6 .deg. and power consumption of 0.3mW..

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.913-914
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• 2008

This paper presents a method of adaptive image enhancement with dynamic range compression and contrast enhancement. The dynamic range compression is to adaptively enhance the dark area using illumination component of DCT compression block. The contrast enhancement is to modify the image contrast using retinex theory that uses the HVS properties. The block artifacts and other noises, caused by processing in the compression domain, were removed by after processing.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.521-524
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• 1999

In spite of advances in image resolution and film contrast, check screen/film mammography remains one of diagnostic imaging modality where the image interpretation is very difficult. For the enhancement of film mammography, in this paper, dyadic wavelet transform is introduced. An unsharp masking technique is proposed and performed in wavelet domain. In addition, simple nonlinear enhancement and a denosing stage that preserves edges using wavelet shrinkage are computed into this technique. In this paper. we propose a new method for the gain setting of nonlinear enhancement and show result and comparison.

• Journal of Multimedia Information System
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• 제4권2호
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• pp.89-92
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• 2017

This paper investigates simple gray level image enhancement technique based on Genetic Algorithms and Local Statistics. The task of GA is to adapt the parameters of local sliding masks over pixels, finding out the best parameters preserving the brightness and possibly preventing the creation of intensity artifacts in the local area of images. The algorithm is controlled by GA as to enhance the contrast and details in the images automatically according to an object fitness criterion. Results obtained in terms of subjective and objective evaluations, show the plausibility of the method suggested here.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(4)
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• pp.5-8
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• 2002

The paper handles a skin tone enhancement within digitalized images, which is based on human favorite skin color. To archive a human-favorite skin tone area, lots of observers are participated in visual experiments. The statistical result of the visual experiment was reflected in a proposed skin tone enhancement algorithm and gives more reasonable human-friendly skin color reproduction on a display device. This research was accomplished to implement in our DTV related application.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(4)
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• pp.275-278
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• 2002

Sharpness enhancement, which strengthen the edge(high frequency) of image, is widely studied for image processing research area. In this paper, psychophysical experiment is conducted by the 20 observers with simple linear unsharp masking for sharpness enhancement. The experimental results extracted using z-score analysis and linear regression suggests observer preferable sharpness enhancement method for digital television.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.794-797
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• 2007

We have developed the adaptive contrast ratio enhancement algorithm for mobile LCD. This algorithm aims at effective contrast ratio enhancement with minimizing degeneration of color and white balance. It also is very simple to fit mobile LCD system.