• 제목/요약/키워드: Multi-images

검색결과 1,996건 처리시간 0.025초

텍스쳐 추출시 제한된 수의 참여 영상을 이용한 multi-view 영상 개선 알고리즘 (An algorithm for the multi-view image improvement with the restricted number of images in texture extraction)

  • 김도현;양영일
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1998년도 하계종합학술대회논문집
    • /
    • pp.773-776
    • /
    • 1998
  • In this paper, we propose an efficient multi-view images coding algorithm which finds the optimal texture from the restricted number of multi-view images. The X-Y plane of the normalized object space is divided into triangular patches. The depth value of the node is determined by applying the block based disparity compensation method and then the texture of the each patch is extracted by applying the affine transformation patch is extracted by applying the affine transformation based disparity compensation method to the multi-view images. We restricted the number of images contributed to determining the texture comapred to traditional methods which use all the multi-view images in the texture extraction. Experimental results show that the SNR of images encoded by the proposed algorithm is better than that of imaes encoded by the traditional method by the amount about 0.2dB for the test sets of multi-view images called dragon, kid, city and santa. The recovered images from the encoded data by the proposed method show the better visual images than the recovered images from the encoded data by the traditional methods.

  • PDF

ASAR AP 다중편파 및 MULTI-LOOK 에 의한 선박탐지 연구 (SHIP DETECTION APPROACH BASED ON CROSSCORRELATION FROM DUAL-POLARIZATION DATA)

  • Yang, Chan-Su;Ouchi, Kazuo
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2008년도 춘계학술대회 논문집
    • /
    • pp.180-184
    • /
    • 2008
  • Preliminary results are reported on ship detection using coherence images computed from crosscorrelating images of multi-look-processed dual-polarization data (HH and HV) of ENVISAT ASAR. The traditional techniques of ship detection by radars such as CFAR (Constant False Alarm Rate) rely on the amplitude data, and therefore the detection tends to become difficult when the amplitudes of ships images are at similar level as the mean amplitude of surrounding sea clutter. The proposed method utilizes the property that the multi-look images of ships are correlated with each other. Because the inter-look images of sea surface are covered by uncorrelated speckle, crosscorrelation of multi-look images yields the different degrees of coherence between the images and water. The polarimetric information of ships, land and intertidal zone are first compared based on the cross-correlation between HH and HV. In the next step, we examine the technique when the dual-polarization data are split into two multi-look images.

  • PDF

입력 영상의 방사학적 불일치 보정이 다중 센서 고해상도 위성영상의 시공간 융합에 미치는 영향 (Effect of Correcting Radiometric Inconsistency between Input Images on Spatio-temporal Fusion of Multi-sensor High-resolution Satellite Images)

  • 박소연;나상일;박노욱
    • 대한원격탐사학회지
    • /
    • 제37권5_1호
    • /
    • pp.999-1011
    • /
    • 2021
  • 다중 센서 영상으로부터 공간 및 시간해상도가 모두 높은 영상을 예측하는 시공간 융합에서 다중 센서 영상의 방사학적 불일치는 예측 성능에 영향을 미칠 수 있다. 이 연구에서는 다중 센서 위성영상의 서로 다른 분광학적 특성을 보정하는 방사보정이 융합 결과에 미치는 영향을 분석하였다. 두 농경지에서 얻어진 Sentinel-2, PlanetScope 및 RapidEye 영상을 이용한 사례연구를 통해 상대 방사보정의 효과를 정량적으로 분석하였다. 사례연구 결과, 상대 방사보정을 적용한 다중 센서 영상을 사용하였을 때 융합의 예측 정확도가 향상되었다. 특히 입력 자료 간 상관성이 낮은 경우에 상대 방사보정에 의한 예측 정확도 향상이 두드러졌다. 분광 특성의 차이를 보이는 다중 센서 자료를 서로 유사하게 변환함으로써 예측 성능이 향상된 것으로 보인다. 이 결과를 통해 상대 방사보정은 상관성이 낮은 다중 센서 위성영상의 시공간 융합에서 예측 능력을 향상시키기 위해 필요할 것으로 판단된다.

다중 거칠기 벡터와 통계적 분류기를 이용한 초음파 간 영상 분류에 관한 연구 (A Study on the Classification of Ultrasonic Liver Images Using Multi Texture Vectors and a Statistical Classifier)

  • 정정원;김동윤
    • 대한의용생체공학회:의공학회지
    • /
    • 제17권4호
    • /
    • pp.433-442
    • /
    • 1996
  • Since one texture property(i.e coarseness, orientation, regularity, granularity) for ultrasound liver ages was not sufficient enough to classify the characteristics of livers, we used multi texture vectors tracted from ultrasound liver images and a statistical classifier. Multi texture vectors are selected among the feature vectors of the normal liver, fat liver and cirrhosis images which have a good separability in those ultrasound liver images. The statistical classifier uses multi texture vectors as input vectors and classifies ultrasound liver images for each multi texture vector by the Bayes decision rule. Then the decision of the liver disease is made by choosing the maximum value from the averages of a posteriori probability for each multi texture vector In our simulation, we obtained higtler correct ratio than that of other methods using single feature vector, for the test set the correct ratio is 94% in the normal liver, 84% in the fat liver and 86% in the cirrhosis liver.

  • PDF

SHIP DETECTION APPROACH BASED ON CROSS CORRELATION FROM ENVISAT ASAR AP DATA

  • Yang, Chan-Su;Ouchi, Kazuo
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
    • /
    • pp.262-265
    • /
    • 2007
  • Preliminary results are reported on ship detection using coherence images computed from cross-correlating images of multi-look-processed dual-polarization data (HH and HV) of ENVISAT ASAR. The traditional techniques of ship detection by radars such as CFAR (Constant False Alarm Rate) rely on the amplitude data, and therefore the detection tends to become difficult when the amplitudes of ships images are at similar level as the mean amplitude of surrounding sea clutter. The proposed method utilizes the property that the multi-look images of ships are correlated with each other. Because the inter-look images of sea surface are covered by uncorrelated speckle, cross-correlation of multi-look images yields the different degrees of coherence between the images and water. The polarimetric information of ships, land and intertidal zone are first compared based on the cross-correlation between HH and HV. In the next step, we examine the technique when the dual-polarization data are split into two multi-look Images.

  • PDF

Analysis of Semantic Relations Between Multimodal Medical Images Based on Coronary Anatomy for Acute Myocardial Infarction

  • Park, Yeseul;Lee, Meeyeon;Kim, Myung-Hee;Lee, Jung-Won
    • Journal of Information Processing Systems
    • /
    • 제12권1호
    • /
    • pp.129-148
    • /
    • 2016
  • Acute myocardial infarction (AMI) is one of the three emergency diseases that require urgent diagnosis and treatment in the golden hour. It is important to identify the status of the coronary artery in AMI due to the nature of disease. Therefore, multi-modal medical images, which can effectively show the status of the coronary artery, have been widely used to diagnose AMI. However, the legacy system has provided multi-modal medical images with flat and unstructured data. It has a lack of semantic information between multi-modal images, which are distributed and stored individually. If we can see the status of the coronary artery all at once by integrating the core information extracted from multi-modal medical images, the time for diagnosis and treatment will be reduced. In this paper, we analyze semantic relations between multi-modal medical images based on coronary anatomy for AMI. First, we selected a coronary arteriogram, coronary angiography, and echocardiography as the representative medical images for AMI and extracted semantic features from them, respectively. We then analyzed the semantic relations between them and defined the convergence data model for AMI. As a result, we show that the data model can present core information from multi-modal medical images and enable to diagnose through the united view of AMI intuitively.

Study on Ship Detection Using SAR Dual-polarization Data: ENVISAT ASAR AP Mode

  • Yang, Chan-Su;Ouchi, Kazuo
    • 대한원격탐사학회지
    • /
    • 제24권5호
    • /
    • pp.445-452
    • /
    • 2008
  • Preliminary results are reported on ship detection using coherence images computed from cross-correlating images of multi-look-processed dual-polarization data (HH and HV) of ENVISAT ASAR. The traditional techniques of ship detection by radars such as CFAR (Constant False Alarm Rate) rely on the amplitude data, and therefore the detection tends to become difficult when the amplitudes of ships images are at similar level as the mean amplitude of surrounding sea clutter. The proposed method utilizes the property that the multi-look images of ships are correlated with each other. Because the inter-look images of sea surface are covered by uncorrelated speckle, cross-correlation of multi-look images yields the different degrees of coherence between the images and water. In this paper, the polarimetric information of ships, land and intertidal zone are first compared based on the cross-correlation between HH and HV images, In the next step, we examine the technique when the dual-polarization data are split into two multi-look images, It was shown that the inter-look cross-correlation method could be applicable in the performance improvement of small ship detection and the land masking, It was also found that a simple combination of coherence images from each co-polarised (HH) inter-look and cross-polarised (HV) inter-look data can provide much higher target-detection possibilities.

자유시점 TV를 위한 다시점 비디오의 계층적 깊이 영상 표현과 H.264 부호화 (Layered Depth Image Representation And H.264 Encoding of Multi-view video For Free viewpoint TV)

  • 신종홍
    • 디지털산업정보학회논문지
    • /
    • 제7권2호
    • /
    • pp.91-100
    • /
    • 2011
  • Free viewpoint TV can provide multi-angle view point images for viewer needs. In the real world, But all angle view point images can not be captured by camera. Only a few any angle view point images are captured by each camera. Group of the captured images is called multi-view image. Therefore free viewpoint TV wants to production of virtual sub angle view point images form captured any angle view point images. Interpolation methods are known of this problem general solution. To product interpolated view point image of correct angle need to depth image of multi-view image. Unfortunately, multi-view video including depth image is necessary to develop a new compression encoding technique for storage and transmission because of a huge amount of data. Layered depth image is an efficient representation method of multi-view video data. This method makes a data structure that is synthesis of multi-view color and depth image. This paper proposed enhanced compression method using layered depth image representation and H.264/AVC video coding technology. In experimental results, confirmed high compression performance and good quality reconstructed image.

다시점 카메라 시스템을 이용한 디지털 매팅 방법 (Digital Matting Using Multi-view Camera System)

  • 현명한;호요성
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2007년도 하계종합학술대회 논문집
    • /
    • pp.281-282
    • /
    • 2007
  • In this paper, we propose a method for digital matting using a multi-view camera system. In order to generate multi-view synthetic aperture images, we first move all images obtained from the multi-view camera according to their disparities. After we obtain corresponding trimaps by taking a variance of the synthetic aperture images, we convert the trimaps into multi-view alpha mattes. Experimental results show that the proposed scheme can create the composite images successfully by combining foreground objects with multi-view background images.

  • PDF

Multi-view 영상 코딩에서 영상 개선 알고리듬 (An algorithm for the image improvement in the multi-view images coding)

  • 김도현;최동준;양영일
    • 전자공학회논문지S
    • /
    • 제35S권7호
    • /
    • pp.53-61
    • /
    • 1998
  • In this paper, we propose an efficient multi-view images coding algorithm to find the optimal depth and texture from the set of multi-view images. The proposed algorithm consists of two consecutive steps, i) the depth estraction step, and ii) the texture extraction step, comparedwith the traditional algorithem which finds the depth and texture concurrently. The X-Y plane of the normalized object space is divided into traingular paatches and the Z value of the node is determined in the first step and then the texture of the each patch is extracted in the second step. In the depth extraction step, the depth of the node is determined by applying the block based disparity compensation method to the windowed area centered at the node. In the second step, the texture of the traingular patches is extracted from the multi-view images by applying the affine transformation based disparity compensation method to the traingular pateches with the depth extracted from the first step. Experimental results show that the SNR(Singnal-to- Noise Ratio) of images enconded by our algorithm is better than that of images encoded by the traditional algorithm by the amount about 4dB for for the test sets of multi-view images called dragon, kid, city and santa.

  • PDF