• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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• pp.85-88
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• 2000

We present a new approach to analyzing the dynamic false contour noise of AC plasma display panels (PDP), which is known to degrade the image quality severely. Compared with the existing methods that consider only the amount of light emission from PDP during 1 field time, the proposed approach uses the impulse response model of the human vision system and estimates how the human beings actually feel as the function of time. Experimental results using various benchmark sub-field scan algorithms are included.

• Journal of Information Display
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• 제7권1호
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• pp.30-34
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• 2006

A sub-field rearrangement driving method has been proposed to reduce a DFC (Dynamic False Contour) phenomenon in plasma display panels. The proposed driving method expresses 256 gray levels with 16 sub-fields, while conventional one uses only 8 sub-fields. Notwithstanding the increase in the number of sub-fields, the display time is similar to the conventional 8 sub-fields driving method by appropriate choosing selective writing and selective erasing for sub-fields.

• 조명전기설비학회논문지
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• 제21권9호
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• pp.12-17
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• 2007

The dynamic false contour noise was analyzed with consideration for the phosphor decay time of an ac PDP by computer simulation based on the measurement of the 1/10 phosphor decay times of the primary colors red, green and blue at the main wavelengths of each phosphor. The noise level of dynamic false contour is strongly dependent on phosphor decay time. The noise level decreases incrementally with the phosphor decay time, whereas the noise width increases. The moving velocity of an object does not affect the noise level. The entire experiment was performed under the condition of 8 subfields ADS driving scheme, 2.5[${\mu}sec$] scan speed, and 5[${\mu}sec$] sustain period with VGA grade panel.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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• pp.258-260
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• 2003

In this paper, we study the reduction of the Dynamic False Contour in a new driving method. This method divides scan lines into Multi Blocks, and drives both selective write and selective erase address. Because of the characteristic of proposed waveform, each scan line has a different sustain pulse weight. Therefore, the Dynamic False Contour occurs seriously in the boundary of each Block. Finally, if scan-lines tie several lines, the Dynamic False Contour can reduce in the boundary of each Block.

• Journal of Electrical Engineering and Technology
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• 제8권6호
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• pp.1462-1467
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• 2013

A pseudo 480-Hz drive method has been proposed to reduce the dynamic false contour noise that occurs on flat panel displays with displaying grayscale image in the digital mode, such as plasma display panels. The proposed method makes the image movements nearly continuous by rearranging the 8-bit image data displayed for 1 TV field into 8 subfields. The position of the image data rearranged in subfields has been optimized on the basis of the speed of the moving image by computer simulations for the dynamic false contour noise. It is verified that a significant reduction in the dynamic false contour noise is achieved with the proposed method as compared to the conventional noise reduction technologies. Moreover, to reduce the noise in digital mode displays, the proposed technology requires only 8 subfields. Therefore, there is no reduction in the brightness of the image.

• 방송공학회논문지
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• 제15권5호
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• pp.697-702
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• 2010

디지털 영상 내의 평탄한 영역에 대한 양자화 과정은 종종 의도하지 않은 의사 윤곽 오차 (false contour artifact)를 발생한다. 본 레터논문에서는 통상적인 블록 기반 비디오 부호화 방식의 양자화 과정에서 발생되는 이러한 오차의 효율적 제거 알고리즘을 보인다. 먼저, 입력 블록에 대해 의사 윤곽의 발생 특성에 기반하여 추출된 특징값들을 이용하여 후보 블록을 선정 한다. 그리고, 해당 블록에 대해 미리 준비된 pseudo-random noise mask를 적용함으로써 의사 윤곽을 제거한다. 이러한 후보 블록 선정을 통한 선택적인 필터링 과정은 불필요한 처리를 최소화함으로써, 화질 열화 억제와 연산 복잡도 감소를 동시에 달성한다. 또한 블록 기반의 처리는 비디오 부호화 루프와의 통합을 용이하게 함으로써, 종래의 코덱 루프 밖에서의 후처리 필터링 방식과 비교하여 구현에 필요한 자원 절감과 프레임 지연 방지라는 측면에서 큰 이점을 갖는다. 제안 알고리즘은 H.264/AVC표준 소프트웨어에 구현되어 율-왜곡 최적화(rate-distortion optimization) 관점에서 압축 성능의 저하없이 낮은 복잡도에서 의사 윤곽을 효율적으로 제거함을 확인하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.407-410
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• 2005

For reducing DFC(Dynamic False Contour), we propose a new PDP driving method by rearrangement of sub-fields. The proposed method constructs a frame using 16 sub-fields for expressing 256 gray levels. Although the number of sub-fields increases, the display time increases compared to the conventional 8 sub-fields driving method. This increase in display time is achieved by properly using both selective writing and selective erasing for each sub-field.

• IEIE Transactions on Smart Processing and Computing
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• 제2권2호
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• pp.97-101
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• 2013

Bit-depth expansion is a process of enhancing the image quality by increasing the number of intensity levels. To solve this problem, a hybrid method is proposed, where the pixels are categorized into smooth and complex regions, and are processed using different methods. The pixels in the smooth region are reconstructed with a smooth prior, and a Bayesian estimator is used for the pixels in the complex region. The proposed method effectively removes the false contour artifacts while requiring less computation than conventional methods. In addition, the method shows good quantitative performance, and the PSNR gains over the best existing method are 1.45 dB and 0.26 dB for 4 bits and 3 bits expansion cases, respectively.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권1호
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• pp.46-54
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• 2002

Plasma Display Panel (PDP) is required to be both the determination of white point of each gray level and the inverse gamma correction since no-balanced RGB cell and linear property of PDP, respectively. However, these two methods cause degradation of grey level representation and undesirable false contour in the dark areas on PDP. In this paper, we implemented real time image processor of the proposed error diffusion algorithm and unsharp masking operation to protect the blurring image caused by the error diffusion. Experimental results showed drastic improvements of gray level representation and reduction of undesirable false contour.

• Journal of Information Display
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• 제4권4호
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• pp.8-12
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• 2003

In this paper, we report relatively simple equalizing pulse method for reducing dynamic false contour in PDP. Calculation cost is reduced by limiting pixels to add equalizing pulse and using look-up-table(LUT) for given subfield pattern. Pixels to be modified are determined after comparing selected number of most significant bits(MSB) with those of adjacent pixels. The equalizing pulse amount is determined by consulting LUT, which is for a fixed velocity of 1 pixel/tv field. Even though the suggested scheme does not cover every luminance combination of neighboring pixels, it is expected to work well after appropriate modifications are made according to the velocity.