• Title/Summary/Keyword: image pre-processing

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Contrast Enhancement for Segmentation of Hippocampus on Brain MR Images

  • Sengee, Nyamlkhagva;Sengee, Altansukh;Adiya, Enkhbolor;Choi, Heung-Kook
    • Journal of Korea Multimedia Society
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    • v.15 no.12
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    • pp.1409-1416
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    • 2012
  • An image segmentation result depends on pre-processing steps such as contrast enhancement, edge detection, and smooth filtering etc. Especially medical images are low contrast and contain some noises. Therefore, the contrast enhancement and noise removal techniques are required in the pre-processing. In this study, we present an extension by a novel histogram equalization in which both local and global contrast is enhanced using neighborhood metrics. When checking neighborhood information, filters can simultaneously improve image quality. Most important is that original image information can be used for both global brightness preserving and local contrast enhancement, and image quality improvement filtering. Our experiments confirmed that the proposed method is more effective than other similar techniques reported previously.

Performance analysis on the geometric correction algorithms using GCPs - polynomial warping and full camera modelling algorithm

  • Shin, Dong-Seok;Lee, Young-Ran
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.252-256
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    • 1998
  • Accurate mapping of satellite images is one of the most important Parts in many remote sensing applications. Since the position and the attitude of a satellite during image acquisition cannot be determined accurately enough, it is normal to have several hundred meters' ground-mapping errors in the systematically corrected images. The users which require a pixel-level or a sub-pixel level mapping accuracy for high-resolution satellite images must use a number of Ground Control Points (GCPs). In this paper, the performance of two geometric correction algorithms is tested and compared. One is the polynomial warping algorithm which is simple and popular enough to be implemented in most of the commercial satellite image processing software. The other is full camera modelling algorithm using Physical orbit-sensor-Earth geometry which is used in satellite image data receiving, pre-processing and distribution stations. Several criteria were considered for the performance analysis : ultimate correction accuracy, GCP representatibility, number of GCPs required, convergence speed, sensitiveness to inaccurate GCPs, usefulness of the correction results. This paper focuses on the usefulness of the precision correction algorithm for regular image pre-processing operations. This means that not only final correction accuracy but also the number of GCPs and their spatial distribution required for an image correction are important factors. Both correction algorithms were implemented and will be used for the precision correction of KITSAT-3 images.

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Development of Driver's Safety/Danger Status Cognitive Assistance System Based on Deep Learning (딥러닝 기반의 운전자의 안전/위험 상태 인지 시스템 개발)

  • Miao, Xu;Lee, Hyun-Soon;Kang, Bo-Yeong
    • The Journal of Korea Robotics Society
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    • v.13 no.1
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    • pp.38-44
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    • 2018
  • In this paper, we propose Intelligent Driver Assistance System (I-DAS) for driver safety. The proposed system recognizes safety and danger status by analyzing blind spots that the driver cannot see because of a large angle of head movement from the front. Most studies use image pre-processing such as face detection for collecting information about the driver's head movement. This not only increases the computational complexity of the system, but also decreases the accuracy of the recognition because the image processing system dose not use the entire image of the driver's upper body while seated on the driver's seat and when the head moves at a large angle from the front. The proposed system uses a convolutional neural network to replace the face detection system and uses the entire image of the driver's upper body. Therefore, high accuracy can be maintained even when the driver performs head movement at a large angle from the frontal gaze position without image pre-processing. Experimental result shows that the proposed system can accurately recognize the dangerous conditions in the blind zone during operation and performs with 95% accuracy of recognition for five drivers.

Semiconductor Process Inspection Using Mask R-CNN (Mask R-CNN을 활용한 반도체 공정 검사)

  • Han, Jung Hee;Hong, Sung Soo
    • Journal of the Semiconductor & Display Technology
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    • v.19 no.3
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    • pp.12-18
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    • 2020
  • In semiconductor manufacturing, defect detection is critical to maintain high yield. Currently, computer vision systems used in semiconductor photo lithography still have adopt to digital image processing algorithm, which often occur inspection faults due to sensitivity to external environment. Thus, we intend to handle this problem by means of using Mask R-CNN instead of digital image processing algorithm. Additionally, Mask R-CNN can be trained with image dataset pre-processed by means of the specific designed digital image filter to extract the enhanced feature map of Convolutional Neural Network (CNN). Our approach converged advantage of digital image processing and instance segmentation with deep learning yields more efficient semiconductor photo lithography inspection system than conventional system.

Pre-quantized Image Compression using Wavelet Transform (선 양자화법에 의한 웨이블릿 영상압축)

  • Piao, Yongri;Kim, Seok-Tae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.405-408
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    • 2005
  • This paper proposed the method to images of losses using restorable wavelet transformation. The algorithm proposed in this work stars by processing the pre-quantizer on the original images to organize an image that matches the gray level. The wavelet transformation filter to the original image which is already pre-quantized in order to segment bands. Considering the lowest coding of bands influencing the most to the overall condition of the reconstructed image, it only uses the Huffman coding using prediction. Reconstructed images by proposed algorithm showed higher PSNR when coding images of JPEG or non pre-quantized images. Applying pre-quantizer can control the peak errors and is expected to be useful at mass image compression.

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DPICM subprojectile counting technique using image analysis of infrared camera (적외선 영상해석을 이용한 이중목적탄 자탄계수 계측기법연구)

  • Park, Won-Woo;Choi, Ju-Ho;Lyou, Joon
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.11-16
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    • 1997
  • This paper describes the grenade counting system developed for DPICM submunition analysis using the infrared video streams, and its some video stream processing technique. The video stream data processing procedure consists of four sequences; Analog infrared video stream recording, video stream capture, video stream pre-processing, and video stream analysis including the grenade counting. Some applications of this algorithms to real bursting test has shown the possibility of automation for submunition counting.

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The Study on Optimal Image Processing and Identifying Threshold Values for Enhancing the Accuracy of Damage Information from Natural Disasters (자연재해 피해정보 산출의 정확도 향상을 위한 최적 영상처리 및 임계치 결정에 관한 연구)

  • Seo, Jung-Taek;Kim, Kye-Hyun
    • Spatial Information Research
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    • v.19 no.5
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    • pp.1-11
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    • 2011
  • This study mainly focused on the method of accurately extracting damage information in the im agery change detection process using the constructed high resolution aerial im agery. Bongwha-gun in Gyungsangbuk-do which had been severely damaged from a localized torrential downpour at the end of July, 2008 was selected as study area. This study utilized aerial im agery having photographing scale of 30cm gray image of pre-disaster and 40cm color image of post-disaster. In order to correct errors from the differences of the image resolution of pre-/post-disaster and time series, the prelim inary phase of image processing techniques such as normalizing, contrast enhancement and equalizing were applied to reduce errors. The extent of the damage was calculated using one to one comparison of the intensity of each pixel of pre-/post-disaster im aged. In this step, threshold values which facilitate to extract the extent that damage investigator wants were applied by setting difference values of the intensity of pixel of pre-/post-disaster. The accuracy of optimal image processing and the result of threshold values were verified using the error matrix. The results of the study enabled the early exaction of the extents of the damages using the aerial imagery with identical characteristics. It was also possible to apply to various damage items for imagery change detection in case of utilizing multi-band im agery. Furthermore, more quantitative estimation of the dam ages would be possible with the use of numerous GIS layers such as land cover and cadastral maps.

System Implementation of Paper Currency Discrimination by Using Integrated Image Features (통합 영상 특징에 의한 지폐 분류 시스템의 구현)

  • Gang, Hyeon-In;Choe, Tae-Wan
    • The KIPS Transactions:PartB
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    • v.9B no.4
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    • pp.471-480
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    • 2002
  • In this paper, we implemented a real-time system improving the performance of the paper currency discrimination by integrating a weighted region of interest matching algorithm with a weighted shape feature matching algorithm of the blocked image. The system classifies the paper currency by comparing a query image with compared images based on the database that contain images of paper currency. Especially, the system has good efficiency at the contaminated, rotated, and translated paper currency. The system hardware consists of three parts as follows : the paper currency image acquired by CIS(contact image sensor) is applied to the pre-processing part with A/D converter and PLD. Finally the pre-processed image data are classified by the main image processing part with a high-speed DSP based on the proposed algorithm.

Stroke Width-Based Contrast Feature for Document Image Binarization

  • Van, Le Thi Khue;Lee, Gueesang
    • Journal of Information Processing Systems
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    • v.10 no.1
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    • pp.55-68
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    • 2014
  • Automatic segmentation of foreground text from the background in degraded document images is very much essential for the smooth reading of the document content and recognition tasks by machine. In this paper, we present a novel approach to the binarization of degraded document images. The proposed method uses a new local contrast feature extracted based on the stroke width of text. First, a pre-processing method is carried out for noise removal. Text boundary detection is then performed on the image constructed from the contrast feature. Then local estimation follows to extract text from the background. Finally, a refinement procedure is applied to the binarized image as a post-processing step to improve the quality of the final results. Experiments and comparisons of extracting text from degraded handwriting and machine-printed document image against some well-known binarization algorithms demonstrate the effectiveness of the proposed method.

Design and Implementation of Sensor Network based Autonomous Vehicle Control System (센서 네트워크 기반 자율주행 자동차 제어 시스템 설계 및 구현)

  • Jang, Won-Chul;Kim, Jong-Myon
    • IEMEK Journal of Embedded Systems and Applications
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    • v.7 no.5
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    • pp.247-253
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    • 2012
  • This paper presents sensor network based autonomous vehicle system using a proposed image processing algorithm. The proposed image processing algorithm consists of pre-processing and five-stage image processing: coordinate calculation, driving area decision, line segment calculation, steeling decision, and acceleration decision. We evaluate the performance of the proposed algorithm on both straight road and curved road. Experimental results indicate that the proposed algorithm works well for autonomous vehicles. However, control accuracy of the proposed algorithm decreases as speed is increasing.