• Journal of the Korea Society of Computer and Information
• /
• v.21 no.12
• /
• pp.35-41
• /
• 2016

In this paper, we propose a new real-time dead pixel detection method based on spatial compare filtering, which are usually used in the small target detection. Actually, the soft dead and the small target are cast in the same mold. Our proposed method detect and remove the dead pixels as applying the spatial compare filtering, into the pixel outputs of a detector after the non-uniformity correction. Therefore, we proposed method can effectively detect and replace the dead pixels regardless of the non-uniformity correction performance. In infrared camera, there are usually many dead detector pixels which produce abnormal output caused by manufactural process or operational environment. There are two kind of dead pixel. one is hard dead pixel which electronically generate abnormal outputs and other is soft dead pixel which changed and generated abnormal outputs by the planning process. Infrared camera have to perform non-uniformity correction because of structural and material properties of infrared detector. The hard dead pixels whose offset values obtained by non-uniformity correction are much larger or smaller than the average can be detected easily as dead pixels. However, some dead pixels(soft dead pixel) can remain, because of the difficulty of uncleared decision whether normal pixel or abnormal pixel.

• Journal of the Korea Society of Computer and Information
• /
• v.23 no.11
• /
• pp.1-7
• /
• 2018

In this paper, we propose soft dead pixels detection method by analysing different response at hot and cold images. Abnormal pixels are able to effect detecting a small target. It also makes confusing real target or not cause of changing target size. Almost exist abnormal pixels after image signal processing even if dead pixels are removed by dead pixel compensation are called soft dead pixels. They are showed defect in final image. So removing or compensating dead pixels are very important for detecting object. The key idea of this proposed method, detecting dead pixels, is that most of soft deads have different response characteristics between hot image and cold image. General infrared cameras do NUC to remove FPN. Working 2-reference NUC must be needed getting data, hot & cold images. The way which is proposed dead pixel detection is that we compare response, NUC gain, at each pixel about two different temperature images and find out dead pixels if the pixels exceed threshold about average gain of around pixels.

• Journal of the Institute of Convergence Signal Processing
• /
• v.8 no.4
• /
• pp.237-243
• /
• 2007

In this paper, we propose the Real-time Dead-Pixel Detection and Compensation System for mobile camera and its hardware architecture. The CMOS image sensors as image input devices are becoming popular due to the demand for miniaturized, low-power and cost-effective imaging systems. However a conventional Dead-Pixel Detection Algorithm is disable to detect neighboring dead pixels and it degrades image quality by wrong detection and compensation. To detect dead pixels the proposed system is classifying dead pixels into Hot pixel and Cold pixel. Also, the proposed algorithm is processing line-detector and $5{\times}5$ window-detector consecutively. The line-detector and window-detector can search dead pixels by using one-dimensional(only horizontal) method in low frequency area and two-dimensional(vertical and diagonal) method in high frequency area, respectively. The experimental result shows that it can detect 99% of dead pixels. It was designed in Verilog hardware description language and total gate count is 23K using TSMC 0.25um ASIC library.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.43 no.9 s.351
• /
• pp.38-43
• /
• 2006

In this paper, we propose the efficient dead pixel detection algorithm for CMOS image sensors and its hardware architecture. The CMOS image sensors as image input devices are becoming popular due to the demand for miniaturized, low-power and cost-effective imaging systems. However, the presence of the dead pixels degrade the image quality. To detect the dead pixels, the proposed algorithm is composed of scan, trace and detection step. The experimental results showed that it could detect 99.99% of dead pixels. It was designed in a hardware description language and total logic gate count is 3.2k using 0.25 CMOS standard cell library.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.41 no.9
• /
• pp.49-56
• /
• 2004

A new readout circuit(ROIC) for linear HgCdTe 64${\times}$2 two-color Infrared (IR) detector is described. This circuit is based on the buffered direct injection(BDI) technology with high injection efficiency. By using saturation current isolation circuit, the proposed ROIC removed the problems that LWIR(Long Wavelength InfraRed) signal distort when MWIR(Middle Wavelength InfraRed) signal saturates so that new ROIC has larger measurable temperature range about 120k than that of previous circuit and it is also tolerant for dead pixel in MWIR detector. The designed circuit was fabricated using 0.6um 2-poly 3-metal CMOS process. We measured that the designed circuit outputs MWIR signal and LWIR signal simultaneously and saturation current isolationcircuit also operates well. Next, measured noise was about 53uV at room temperature and it can be assumed that designed circuit can satisfy nearly 95% BLIP condition at 77K.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2010.11a
• /
• pp.660-663
• /
• 2010

현대사회에서 정보통신 분야는 전략산업이며 일상생활에서 필수적인 요소로 자리잡고 있으며 이를 대표하는 것이 모바일 관련 분야라 할 수 있다. 특히, 휴대폰은 단순한 통화 기능 외에 다양한 기능들이 지속적으로 추가되면서 이를 활용한 분야가 다양화되어 가고 있다. 따라서 본 논문에서는 최근에 가장 보편화된 이동통신 수단이 휴대폰에 내장되어 있는 카메라에 대한 각 제조사별 성능을 비교, 분석하였다. 이를 위해 각 제조사별 휴대폰 카메라의 Hot Pixel, Dead Pixel을 검출하고, 빛의 3원색인 RGB 체계를 분석하여 객관적인 성능 비교를 실험하였다.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.44 no.4
• /
• pp.55-62
• /
• 2007

This paper proposes a defective pixel detection algorithm and its hardware structure for CCD/CMOS image sensor. In previous algorithms, the characteristics of image have not been considered. Also, some algorithms need quite a time to detect defective pixels. In order to make up for those disadvantages, the proposed defective pixel detection method detects defective pixels efficiently by considering the edges in the image and verifies them using several frames while checking scene-changes. Whenever scene-change is occurred, potentially defective pixels are checked and confirmed whether it is defective or not. Test results showed that the correct detection rate in a frame was increased 6% and the defective pixel verification time was decreased 60%. The proposed algorithm was implemented with verilog HDL. The edge indicator in color interpolation block was reused. Total logic gate count was 5.4k using 0.25um CMOS standard cell library.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.12 no.2
• /
• pp.97-103
• /
• 2017

Thermal imaging is mainly used in military equipment required for night observation. In particular, technologies of uncooled thermal imaging detectors are being developed as applied to low-cost night observation system. Many system integrators require different specifications of the uncooled thermal imaging camera but their development time is short. In this approach, EOSYSTEM has developed a small size, TEC-less uncooled thermal imaging camera module with $32{\times}32mm$ size and low power consumption. Both domestic detector and import detector are applied to the EOSYSTEM's thermal imaging camera module. The camera module contains efficient infrared image processing algorithms including : Temperature compensation non-uniformity correction, Bad/Dead pixel replacement, Column noise removal, Contrast/Edge enhancement algorithms providing stable and low residual non-uniformity infrared image.

• Proceedings of the KIEE Conference
• /
• 2000.07d
• /
• pp.3230-3232
• /
• 2000

DR (Digital Radiography) system will be the best candidate for next generation x-ray diagnosis system. DR system will replace x-ray film by computer monitor and provide various merits like reduced processing time, easy recording, remote diagnosis and etc. In this paper, we propose the pre-processing algorithm which is designed to compensate dead and defected pixel for x-ray detector panel. We also designed DSP(Digital Signal Processor) based DR image processing board for real-time processing of suggested algorithm.

• Journal of Information Display
• /
• v.13 no.1
• /
• pp.17-20
• /
• 2012

The current panels for liquid crystal display (LCD) TV sets are all characterized by pins placed on two sides. To manufacture one type of panel, a dedicated mask is needed, and the production line should be started once. Moreover, the whole panel needs to be removed if a dead pixel is found. If the panel, however, will first be fabricated with pins placed on four sides and then divided by a cross-cut into four equal-sized panels with pins placed on two sides, one set of masks can be used to manufacture two types of LCD panels, which was referred to by the authors as dual mode. In this paper, the concept of the dual mode and its differences from the conventional way of producing panels are introduced. Its advantages in boosting production efficiency, improving the product's good rate, and lowering the production cost are also described based on case studies. Of particular importance is the fact that the dual mode is very suitable for the trial production of very-large-area LCD TV sets.