• Title/Summary/Keyword: Image Intensity

Search Result 1,695, Processing Time 0.029 seconds

Development and Evaluation of the Usefulness for Hoffman Brain Phantom Based on 3D Printing Technique (3D 프린팅 기법 기반의 Hoffman Brain 팬텀 개발 및 유용성 평가)

  • Park, Hoon-Hee;Lee, Joo-Young
    • Journal of radiological science and technology
    • /
    • v.42 no.6
    • /
    • pp.441-446
    • /
    • 2019
  • The purpose of this paper is to recognize the usefulness of the Phantom produced with 3D printing technology by reproducing the original phantom with 3D printing technology. Using CT, we obtained information from the original phantom. The acquired file was printed by the SLA method of ABS materials. For inspection, SPECT/CT was used to obtain images. We filled the both Phantom with a solution mixed with 99mTcO4 1 mCi in 1 liter of water and acq uired images in accordance with the standard protocol. Using Image J, the SNR for each slice of the image was obtained. As a reference images, AC images were used. For the analysis of acquired images, ROI was set in the White mater and Gray mater sections of each image, and the average Intensity Value within the ROI were compared. According to the results of this study, 3D printed phantom's SNR is about 0.1 higher than the conventional phantom. And the ratio of Intensity Value was shown in the original 1 : 3.4, and the printed phantom was shown to be 1 : 3.2. Therefore, if Calibration Value is applied, It is assumed that it can be used as an alternative to the original.

Setting an Initial Validation Gate based on Signal Intensity for Target Tracking in IR Image Sequences (적외선 영상에서 표적 추적을 위한 신호세기 기반 초기 유효게이트 설정 방법)

  • Yang, Yu Kyung;Kim, Jieun;Lee, Boohwan
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.17 no.1
    • /
    • pp.108-114
    • /
    • 2014
  • This paper describes a method to set an intensity-based initial validation gate for tracking filter while preserves the ability of tracking a target with maximum speed. First, we collected real data set of signal versus distance of an airplane target. And at each data point, we computed maximum distance the target can move. And a function is modeled to expect the maximum moving pixels on the lateral direction based on the intensity of the detected target in IR image sequence. The initial prediction error covariance can be computed using this function to decide the size of the initial validation gate. The simulation results show the proposed method can set the appropriate initial validation gates to track the targets with the maximum speed.

Optical Image Encryption Based on Characteristics of Square Law Detector (세기검출기를 이용한 광 영상 암호화)

  • Lee, Eung-Dae;Park, Se-Jun;Lee, Ha-Un;Kim, Su-Jung
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.39 no.3
    • /
    • pp.34-40
    • /
    • 2002
  • In this paper, a new encryption method for a binary image using Phase modulation and Fourier transform is proposed. For decryption we use the characteristics of square law detector. In encryption process, a key image is obtained by phase modulation of 256 level random pattern and its Fourier transformation, and input image is encrypted by Fourier transforming the multiplication of the phase modulated random pattern and phase modulated input image. The encrypted image and key image have only phase information, so they can not be copied or counterfeited and the original image can not be decrypted without the key image. To reconstruct the original image, each phase mask of the key image and the encrypted image must be placed on each path of the Mach-Zehnder interferometry with Fourier transform lens and the output image is obtained in the form of intensity in the CCD(Charge Coupled Device) camera. The real-time decryption is possible in the proposed system by use of a LCD as a phase modulator and a CCD camera as an intensity detector. The proposed method shows a good performance in the computer simulation and optical experiment as an encryption scheme.

Numerical Analysis of Ultrasonic Radiation Intensities (In Liquid) (초음파의 세기를 구하기 위한 수치 해석적 방법)

  • Lee, Sang Hee
    • Journal of Industrial Technology
    • /
    • v.8
    • /
    • pp.65-70
    • /
    • 1988
  • The intensity of ultrasound in liquid is calculated by improved analytic method. Helmholtz equation or Rayleigh's proposition does not offer the analytic solution. Considering a bounded medium, the use of the image source method in electromagnetic thoery gives a new way of calculating the total ultrasonic intensity in liquid. Some methods of measuring the intensities are also mentioned.

  • PDF

Prostate MR and Pathology Image Fusion through Image Correction and Multi-stage Registration (영상보정 및 다단계 정합을 통한 전립선 MR 영상과 병리 영상간 융합)

  • Jung, Ju-Lip;Jo, Hyun-Hee;Hong, Helen
    • Journal of KIISE:Computing Practices and Letters
    • /
    • v.15 no.9
    • /
    • pp.700-704
    • /
    • 2009
  • In this paper, we propose a method for combining MR image with histopathology image of the prostate using image correction and multi-stage registration. Our method consists of four steps. First, the intensity of prostate bleeding area on T2-weighted MR image is substituted for that on T1-weighted MR image. And two or four tissue sections of the prostate in histopathology image are combined to produce a single prostate image by manual stitching. Second, rigid registration is performed to find the affine transformations that to optimize mutual information between MR and histopathology images. Third, the result of affine registration is deformed by the TPS warping. Finally, aligned images are visualized by the intensity intermixing. Experimental results show that the prostate tumor lesion can be properly located and clearly visualized within MR images for tissue characterization comparison and that the registration error between T2-weighted MR and histopathology image was 0.0815mm.

Development of High-Accuracy Image Centroiding Algorithm for CMOS-based Digital Sun Sensor (CMOS 기반의 디지털 태양센서를 위한 고정밀 이미지 중심 알고리즘의 개발)

  • Lee, Byung-Hoon;Chang, Young-Keun
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.35 no.11
    • /
    • pp.1043-1051
    • /
    • 2007
  • The digital sun sensor calculates the incident sunlight angle using the sunlight image registered on a CMOS image sensor. In order to accomplish this, an exact center of the sunlight image has to be determined. Therefore, an accurate estimate of the centroid is the most important factor in digital sun sensor development. The most general method for determining the centroid is the thresholding method, and this method is also the simplest and easy to implement. Another centering algorithm often used is the image filtering method that utilizes image processing. The sun sensor accuracy using these methods, however, is quite susceptible to noise in the detected sunlight intensity. This is especially true in the thresholding method where the accuracy changes according to the threshold level. In this paper, a template method that uses the sunlight image model to determine the centroid of the sunlight image is suggested, and the performance has been compared and analyzed. The template method suggested, unlike the thresholding and image filtering method, has comparatively higher accuracy. In addition, it has the advantage of having consistent level of accuracy regardless of the noise level, which results in a higher reliability.

Mura Defect Enhancement based on Saliency Map in TFT-LCD Image (TFT-LCD 영상에서 Saliency Map 기반의 얼룩성 결함 강조)

  • Lee, Eun Young;Park, Kil Houm
    • Journal of Korea Multimedia Society
    • /
    • v.19 no.3
    • /
    • pp.626-632
    • /
    • 2016
  • In this paper, we propose the defect emphasis in TFT-LCD panel image. The defect emphasis image consist of S(Shape) map and B(Brightness) map. S map based on DoG(difference of gaussian) is made with the mura defect shape characteristic. And B map use defect intensity property that defect intensity is higher than background. The experiments were conducted to evaluate the performance of the proposed defect emphasis method. The results of experiments show the validity of the defect emphasis using the proposed method.