• Title/Summary/Keyword: image feature extraction

Search Result 1,017, Processing Time 0.028 seconds

Image Retrieval using Local Color Histogram and Shape Feature (지역별 색상 분포 히스토그램과 모양 특징을 이용한 영상 검색)

  • 정길선;김성만;이양원
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 1999.05a
    • /
    • pp.50-54
    • /
    • 1999
  • This paper is proposed to image retrieval system using color and shape feature. Color feature used to four maximum value feature among the maximum value extracted from local color distribution histogram. The preprocessing of shape feature consist of edge extraction and weight central point extraction and angular sampling. The sum of distance from weight central point to contour and variation and max/min used to shape feature. The similarity is estimated compare feature of query image with the feature of images in database and the candidate of image is retrieved in order of similarity. We evaluate the effectiveness of shape feature and color feature in experiment used to two hundred of the closed image. The Recall and the Precision is each 0.72 and 0.53 in the result of average experiment. So the proposed method is presented useful method.

  • PDF

A STUDY ON SPATIAL FEATURE EXTRACTION IN THE CLASSIFICATION OF HIGH RESOLUTIION SATELLITE IMAGERY

  • Han, You-Kyung;Kim, Hye-Jin;Choi, Jae-Wan;Kim, Yong-Il
    • Proceedings of the KSRS Conference
    • /
    • 2008.10a
    • /
    • pp.361-364
    • /
    • 2008
  • It is well known that combining spatial and spectral information can improve land use classification from satellite imagery. High spatial resolution classification has a limitation when only using the spectral information due to the complex spatial arrangement of features and spectral heterogeneity within each class. Therefore, extracting the spatial information is one of the most important steps in high resolution satellite image classification. In this paper, we propose a new spatial feature extraction method. The extracted features are integrated with spectral bands to improve overall classification accuracy. The classification is achieved by applying a Support Vector Machines classifier. In order to evaluate the proposed feature extraction method, we applied our approach to KOMPSAT-2 data and compared the result with the other methods.

  • PDF

Selective Feature Extraction Method Between Markov Transition Probability and Co-occurrence Probability for Image Splicing Detection (접합 영상 검출을 위한 마르코프 천이 확률 및 동시발생 확률에 대한 선택적 특징 추출 방법)

  • Han, Jong-Goo;Eom, Il-Kyu;Moon, Yong-Ho;Ha, Seok-Wun
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.20 no.4
    • /
    • pp.833-839
    • /
    • 2016
  • In this paper, we propose a selective feature extraction algorithm between Markov transition probability and co-occurrence probability for an effective image splicing detection. The Features used in our method are composed of the difference values between DCT coefficients in the adjacent blocks and the value of Kullback-Leibler divergence(KLD) is calculated to evaluate the differences between the distribution of original image features and spliced image features. KLD value is an efficient measure for selecting Markov feature or Co-occurrence feature because KLD shows non-similarity of the two distributions. After training the extracted feature vectors using the SVM classifier, we determine whether the presence of the image splicing forgery. To verify our algorithm we used grid search and 6-folds cross-validation. Based on the experimental results it shows that the proposed method has good detection performance with a limited number of features compared to conventional methods.

An Improved Texture Feature Extraction Method for Recognizing Emphysema in CT Images

  • Peng, Shao-Hu;Nam, Hyun-Do
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.24 no.11
    • /
    • pp.30-41
    • /
    • 2010
  • In this study we propose a new texture feature extraction method based on an estimation of the brightness and structural uniformity of CT images representing the important characteristics for emphysema recognition. The Center-Symmetric Local Binary Pattern (CS-LBP) is first used to combine gray level in order to describe the brightness uniformity characteristics of the CT image. Then the gradient orientation difference is proposed to generate another CS-LBP code combining with gray level to represent the structural uniformity characteristics of the CT image. The usage of the gray level, CS-LBP and gradient orientation differences enables the proposed method to extract rich and distinctive information from the CT images in multiple directions. Experimental results showed that the performance of the proposed method is more stable with respect to sensitivity and specificity when compared with the SGLDM, GLRLM and GLDM. The proposed method outperformed these three conventional methods (SGLDM, GLRLM, and GLDM) 7.85[%], 22.87[%], and 16.67[%] respectively, according to the diagnosis of average accuracy, demonstrated by the Receiver Operating Characteristic (ROC) curves.

Enhanced CT-image for Covid-19 classification using ResNet 50

  • Lobna M. Abouelmagd;Manal soubhy Ali Elbelkasy
    • International Journal of Computer Science & Network Security
    • /
    • v.24 no.1
    • /
    • pp.119-126
    • /
    • 2024
  • Disease caused by the coronavirus (COVID-19) is sweeping the globe. There are numerous methods for identifying this disease using a chest imaging. Computerized Tomography (CT) chest scans are used in this study to detect COVID-19 disease using a pretrain Convolutional Neural Network (CNN) ResNet50. This model is based on image dataset taken from two hospitals and used to identify Covid-19 illnesses. The pre-train CNN (ResNet50) architecture was used for feature extraction, and then fully connected layers were used for classification, yielding 97%, 96%, 96%, 96% for accuracy, precision, recall, and F1-score, respectively. When combining the feature extraction techniques with the Back Propagation Neural Network (BPNN), it produced accuracy, precision, recall, and F1-scores of 92.5%, 83%, 92%, and 87.3%. In our suggested approach, we use a preprocessing phase to improve accuracy. The image was enhanced using the Contrast Limited Adaptive Histogram Equalization (CLAHE) algorithm, which was followed by cropping the image before feature extraction with ResNet50. Finally, a fully connected layer was added for classification, with results of 99.1%, 98.7%, 99%, 98.8% in terms of accuracy, precision, recall, and F1-score.

Effects of Preprocessing and Feature Extraction on CNN-based Fire Detection Performance (전처리와 특징 추출이 CNN기반 화재 탐지 성능에 미치는 효과)

  • Lee, JeongHwan;Kim, Byeong Man;Shin, Yoon Sik
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.23 no.4
    • /
    • pp.41-53
    • /
    • 2018
  • Recently, the development of machine learning technology has led to the application of deep learning technology to existing image based application systems. In this context, some researches have been made to apply CNN (Convolutional Neural Network) to the field of fire detection. To verify the effects of existing preprocessing and feature extraction methods on fire detection when combined with CNN, in this paper, the recognition performance and learning time are evaluated by changing the VGG19 CNN structure while gradually increasing the convolution layer. In general, the accuracy is better when the image is not preprocessed. Also it's shown that the preprocessing method and the feature extraction method have many benefits in terms of learning speed.

A Defect Detection Algorithm of Denim Fabric Based on Cascading Feature Extraction Architecture

  • Shuangbao, Ma;Renchao, Zhang;Yujie, Dong;Yuhui, Feng;Guoqin, Zhang
    • Journal of Information Processing Systems
    • /
    • v.19 no.1
    • /
    • pp.109-117
    • /
    • 2023
  • Defect detection is one of the key factors in fabric quality control. To improve the speed and accuracy of denim fabric defect detection, this paper proposes a defect detection algorithm based on cascading feature extraction architecture. Firstly, this paper extracts these weight parameters of the pre-trained VGG16 model on the large dataset ImageNet and uses its portability to train the defect detection classifier and the defect recognition classifier respectively. Secondly, retraining and adjusting partial weight parameters of the convolution layer were retrained and adjusted from of these two training models on the high-definition fabric defect dataset. The last step is merging these two models to get the defect detection algorithm based on cascading architecture. Then there are two comparative experiments between this improved defect detection algorithm and other feature extraction methods, such as VGG16, ResNet-50, and Xception. The results of experiments show that the defect detection accuracy of this defect detection algorithm can reach 94.3% and the speed is also increased by 1-3 percentage points.

Automatic Disk Disease Recognition based on Feature Vector in T-L Spine Magnetic Resonance Image (척추 자기 공명 영상에서 특징 벡터에 기반 한 디스크 질환의 자동 인식)

  • 홍재성;이성기
    • Journal of Biomedical Engineering Research
    • /
    • v.19 no.3
    • /
    • pp.233-242
    • /
    • 1998
  • In anatomical aspects, magnetic resonance image offers more accurate information than other medical images such as X ray ultrasonic and CT images. This paper introduces a method that recognizes disk diseases from spine MR images. In this method, image enhancement, image segmentation and feature extraction for sagittal plane and axial plane images are performed to separate the disk region. And then template matching method is used to extract disease region for axial plane imges. Finally, disease feature vectors are integrated and disease discrimination processes are performed. Experimental results show that the proposed method discriminates between normal and diseased disk with a considerable recognition ratio.

  • PDF

ROI Based Object Extraction Using Features of Depth and Color Images (깊이와 칼라 영상의 특징을 사용한 ROI 기반 객체 추출)

  • Ryu, Ga-Ae;Jang, Ho-Wook;Kim, Yoo-Sung;Yoo, Kwan-Hee
    • The Journal of the Korea Contents Association
    • /
    • v.16 no.8
    • /
    • pp.395-403
    • /
    • 2016
  • Recently, Image processing has been used in many areas. In the image processing techniques that a lot of research is tracking of moving object in real time. There are a number of popular methods for tracking an object such as HOG(Histogram of Oriented Gradients) to track pedestrians, and Codebook to subtract background. However, object extraction has difficulty because that a moving object has dynamic background in the image, and occurs severe lighting changes. In this paper, we propose a method of object extraction using depth image and color image features based on ROI(Region of Interest). First of all, we look for the feature points using the color image after setting the ROI a range to find the location of object in depth image. And we are extracting an object by creating a new contour using the convex hull point of object and the feature points. Finally, we compare the proposed method with the existing methods to find out how accurate extracting the object is.

A Study on Implementation of the High Speed Feature Extraction System Based on Block Type Classification (블록 유형 분류 알고리즘 기반 고속 특징추출 시스템 구현에 관한 연구)

  • Lee, Juseong;An, Ho-Myoung
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.12 no.3
    • /
    • pp.186-191
    • /
    • 2019
  • In this paper, we propose a implementation approach of the high-speed feature extraction algorithm. The proposed method is based on the block type classification algorithm which reduces the computation time when target macro block is divided to smooth block type that has no image features. It is quantitatively identified that occurs at 29.5% of the total image using 200 standard test images with $64{\times}64$ macro block size. This means that within a standard test image containing various image information, 29.5% can reduce the complexity of the operation. When the proposed approach is applied to the Canny edge detection, the required latency of the edge detection can be completely eliminated, such as 2D derivative filter, gradient magnitude/direction computation, non-maximal suppression, adaptive threshold calculation, hysteresis thresholding. Also, it is expected that operation time of the feature detection can be reduced by applying block type classification algorithm to various feature extraction algorithms in this way.