• Title/Summary/Keyword: Low-resolution image

Search Result 866, Processing Time 0.036 seconds

A Study on Medical Image Watermarking with Wavelet Packet (웨이블릿 패킷을 적용한 의료영상의 워터마킹에 관한 연구)

  • 이승용;김윤호;류광렬
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2002.11a
    • /
    • pp.222-225
    • /
    • 2002
  • The watermarking on medical images with wavelet packet is presented. The wavelet packet produces the enhancing the resolution from low to high band that minimize the loss on the band. The result on experiment is that PSNR is 0.1dB on image quality and PSNR is 28dB on the durability in compressed ratio 60% over. This proposal allows an enhancing and robust image to stand and oppose the distortion and modification by intention.

  • PDF

Detection of Abnormal Regions Neural-Network In Chest Photofluorography (신경회로망을 이용한 흉부 X-선 간접촬영에서의 병변검출)

  • Lee, Hoo-Min;Yun, Kwang-Ho;Kim, Sang-Hoon;Nam, Moon-Hyun
    • Proceedings of the KIEE Conference
    • /
    • 2000.07d
    • /
    • pp.2482-2484
    • /
    • 2000
  • In this paper, we have developed an automated computer aided diagnostic (CAD) scheme by using artificial neural networks(ANN) on guantitative analysis of chest photofluorography. The first ANN performs the detection of suspicious regions in a low resolution image. This was trained specifically on the problem of detecting abnormal regions digitized chest photofluorography. The second space matching method was used to distinguish between normal and abnormal regions of interest(ROI). If the ratio of the number of abnormal ROI to the total number of all ROI in a chest image was greater than a specified threshold level, the image was classified as abnormal.

  • PDF

Extraction of Renal Glomeruli Region using Genetic Algorithm (유전적 알고리듬을 이용한 신장 사구체 영역의 추출)

  • Kim, Eung-Kyeu
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.46 no.2
    • /
    • pp.30-39
    • /
    • 2009
  • Extraction of glomeruli region plays a very important role for diagnosing nephritis automatically. However, it is not easy to extract glomeruli region correctly because the difference between glomeruli region and other region is not obvious, simultaneously unevennesses that is brought in the sampling process and in the imaging process. In this study, a new method for extracting renal glomeruli region using genetic algorithm is proposed. The first, low and high resolution images are obtained by using Laplacian-Gaussian filter with ${\sigma}=2.1$ and ${\sigma}=1.8$, then, binary images by setting the threshold value to zero are obtained. And then border edge is detected from low resolution images, the border of glomeruli is expressed by a closed B-splines' curve line. The parameters that decide the closed curve line with this low resolution image prevent the noises and the border lines from breaking off in the middle by searching using genetic algorithm. Next, in order to obtain more precise border edges of glomeruli, the number of node points is increased and corrected in order from eight to sixteen and thirty two from high resolution images. Finally, the validity of this proposed method is shown to be effective by applying to the real images.

High-Speed CMOS Binary Image Sensor with Gate/Body-Tied PMOSFET-Type Photodetector

  • Choi, Byoung-Soo;Jo, Sung-Hyun;Bae, Myunghan;Kim, Jeongyeob;Choi, Pyung;Shin, Jang-Kyoo
    • Journal of Sensor Science and Technology
    • /
    • v.23 no.5
    • /
    • pp.332-336
    • /
    • 2014
  • In this paper, we propose a complementary metal oxide semiconductor (CMOS) binary image sensor with a gate/body-tied (GBT) PMOSFET-type photodetector for high-speed operation. The GBT photodetector of an active pixel sensor (APS) consists of a floating gate ($n^+$-polysilicon) tied to the body (n-well) of the PMOSFET. The p-n junction photodiode that is used in a conventional APS has a good dynamic range but low photosensitivity. On the other hand, a high-gain GBT photodetector has a high level of photosensitivity but a narrow dynamic range. In addition, the pixel size of the GBT photodetector APS is less than that of the conventional photodiode APS because of its use of a PMOSFET-type photodetector, enabling increased image resolution. A CMOS binary image sensor can be designed with simple circuits, as a complex analog to digital converter (ADC) is not required for binary processing. Because of this feature, the binary image sensor has low power consumption and high speed, with the ability to switch back and forth between a binary mode and an analog mode. The proposed CMOS binary image sensor was simulated and designed using a standard CMOS $0.18{\mu}m$ process.

APBT-JPEG Image Coding Based on GPU

  • Wang, Chengyou;Shan, Rongyang;Zhou, Xiao
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.9 no.4
    • /
    • pp.1457-1470
    • /
    • 2015
  • In wireless multimedia sensor networks (WMSN), the latency of transmission is an increasingly problem. With the improvement of resolution, the time cost in image and video compression is more and more, which seriously affects the real-time of WMSN. In JPEG system, the core of the system is DCT, but DCT-JPEG is not the best choice. Block-based DCT transform coding has serious blocking artifacts when the image is highly compressed at low bit rates. APBT is used in this paper to solve that problem, but APBT does not have a fast algorithm. In this paper, we analyze the structure in JPEG and propose a parallel framework to speed up the algorithm of JPEG on GPU. And we use all phase biorthogonal transform (APBT) to replace the discrete cosine transform (DCT) for the better performance of reconstructed image. Therefore, parallel APBT-JPEG is proposed to solve the real-time of WMSN and the blocking artifacts in DCT-JPEG in this paper. We use the CUDA toolkit based on GPU which is released by NVIDIA to design the parallel algorithm of APBT-JPEG. Experimental results show that the maximum speedup ratio of parallel algorithm of APBT-JPEG can reach more than 100 times with a very low version GPU, compared with conventional serial APBT-JPEG. And the reconstructed image using the proposed algorithm has better performance than the DCT-JPEG in terms of objective quality and subjective effect. The proposed parallel algorithm based on GPU of APBT also can be used in image compression, video compression, the edge detection and some other fields of image processing.

Image Restoration Considering Chromatic Aberration Problem of Multi-Spectral Filter Array Image (다중 분광 필터 배열 영상의 색수차 문제를 고려한 영상 복원 알고리즘)

  • Kwon, Ji Yong;Kang, Moon Gi
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.53 no.5
    • /
    • pp.123-131
    • /
    • 2016
  • To capture color and near-infrared images simultaneously, a multi-spectral filter array(MSFA) sensor is used. This is because an NIR band gives additional invisible information to human eyes to see subject under extremely low light level. However, because lenses have different refractive indices for different wavelengths, lenses may fail to focus widely different rays to the same convergence point. This is why a chromatic aberration(CA) problem occurs and images are degraded. In this paper, the image restoration algorithm for an MSFA image, which removes the CA problem, is presented. The obtained MSFA image is filtered by the estimated low-pass kernel to generate a base image. This base image is used to remove CA problem in multi-spectral(MS) images. By modeling the image degradation process and by using the least squares approach of the difference between the high-frequencies of the base and MS images, the desired high-resolution MS images are reconstructed. The experimental results show that the proposed algorithm performs well in estimating the high-quality MS images and reducing the chromatic aberration problem.

3-D Underwater Object Restoration Using Ultrasonic Transducer Fabricated with 1-3 Type Piezoceramic/Polymer Composite and Neural Networks (1-3형 복합압전체로 제작한 초음파 트랜스듀서와 신경회로망을 이용한 3차원 수중 물체복원)

  • Jo, Hyeon-Cheol;Lee, Gi-Seong;Choe, Heon-Il;Sa, Gong-Geon
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.48 no.6
    • /
    • pp.456-461
    • /
    • 1999
  • In this study, the characteristics of Ultrasonic Transducer fabricated with PZT-Polymer 1-3 type piezoelectric ceramic/polymer composite are investigated. 3-D underwater object restoration using the self-made ultrasonic transducer and modified SCL(Simple Competitive Learning) neural network was presented. The ultrasonic transducer was satisfied with the required condition of commerical ultrasonic transducer in underwater. The modified SCL neural network using the acquired object data $16\times16$ low resolution image was used for object restoration of $32\times32$ high resolution image. The experimental results have shown that the ultrasonic transducer fabricated with PZT-Polymer 1-3 type piezoelectric ceramic/polymer composite could be applied for SONAR system.

  • PDF

Sub-pixel Motion Compensated Deinterlacing Algorithm (부화소 단위의 움직임 정보를 고려한 순차 주사화)

  • 박민규;최종성;강문기
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.40 no.5
    • /
    • pp.322-331
    • /
    • 2003
  • Advances of high-definition television(HDTV) and personal computers call for the mutual conversion between interlaced signal and progressive signal. Especially, deinterlacing which is known as an interlaced to progressive conversion has been recently required and investigated. In this paper, we propose new deinterlacing algorithm considering sub-pixel motion information. In order to reduce the error of motion estimation, we analyze the effect of inaccurate sub-pixel motion information and model it as zero-mean Gaussian noises added respectively to each low resolution image(field). The error caused by inaccurate motion information is reduced by determining regularization parameter according to the error of motion estimation in each channel. The validity of the proposed algorithm is demonstrated both theoretically and experimentally in this paper.

Defect Detection of Flat Panel Display Using Wavelet Transform (웨이블릿 변환을 이용한 FPD 결함 검출)

  • Kim, Sang-Ji;Lee, Youn-Ju;Yoon, Jeong-Ho;You, Hun;Lee, Byung-Gook;Lee, Joon-Jae
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • v.10 no.1
    • /
    • pp.47-60
    • /
    • 2006
  • Due to the uneven illumination of FPD panel surface, it is difficult to detect the defects. The paper proposes a method to find the uneven illumination compensation using wavelets, which are done based on multi-resolution structure. The first step is to decompose the image into multi-resolution levels. Second, elimination of lowest smooth sub-image with highest frequency band removes the high frequency noise and low varying illumination. In particular, the main algorithm was implemented by lifting scheme for realtime inline process.

  • PDF

A Technique to Improve the Readability of Ancient Inscription by Using Optical Triangulation Measurement Principle (광삼각법 측정 원리를 이용한 금석문 가독성 향상 방법)

  • Lee, Geun-Ho;Ko, Sun-Woo;Choi, Won-Ho
    • Journal of Information Technology Services
    • /
    • v.11 no.sup
    • /
    • pp.103-111
    • /
    • 2012
  • In epigraph field to study ancient scripts, alternative readability improvement technologies have been developed to replace existing rubbing method which has low resolution and causes surface pollution of heritages from the viewpoints of extraction process and used materials. Recently many methods which are based on analysis of pixel data for extracting outlines of the specific image have been developed with advancement of image processing techniques. But these methods are not applicable and the results are not satisfied in the damaged inscriptions which are weathered by wind and rain for a long time and in the narrowed one. In this paper laser scanning techniques which uses optical triangulation measurement principle are developed to minimize scanning error. The proposed techniques are consisted of 3 parts:(1) the understanding of optical triangulation measurement principle to find scanning guideline (2) determinations of points interval, scanning distance and scanning angle to guarantee scanning data quality (3) identification of valid point data area which will be used in registration process. The proposed character identification method contributed in decoding an ancient inscription on SeukBingGo in Kyungju.