• Title/Summary/Keyword: rotation normalization

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Rotation Angle Estimation of Multichannel Images (다채널 이미지의 회전각 추정)

  • Lee Bong-Kyu;Yang Yo-Han
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.51 no.6
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    • pp.267-271
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    • 2002
  • The Hotelling transform is based on statistical properties of an image. The principal uses of this transform are in data compression. The basic concept of the Hotelling transform is that the choice of basis vectors pointing the direction of maximum variance of the data. This property can be used for rotation normalization. Many objects of interest in pattern recognition applications can be easily standardized by performing a rotation normalization that aligns the coordinate axes with the axes of maximum variance of the pixels in the object. However, this transform can not be used to rotation normalization of color images directly. In this paper, we propose a new method for rotation normalization of color images based on the Hotelling transform. The Hotelling transform is performed to calculate basis vectors of each channel. Then the summation of vectors of all channels are processed. Rotation normalization is performed using the result of summation of vectors. Experimental results showed the proposed method can be used for rotation normalization of color images effectively.

A Rotation Resistant Logo Embedding Watermark on Frequency Domain (회전 변환에 강인한 주파수 영역 로고 삽입 워터마크 방법)

  • Lee, In-Jung;Lee, Hyoung;Yoo, Hye-Rim;Min, Joon-Young
    • Journal of Information Technology Applications and Management
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    • v.14 no.1
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    • pp.137-144
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    • 2007
  • In this paper, we propose a rotation resistant robust logo embedding watermarking technique. Geometric manipulations make the detection process very complex and difficult. Watermark embedding in the normalized image directly suffers from smoothing effect due to the interpolation during the image normalization. This can be avoided by estimating the transform parameters using image normalization angle and moments, instead of embedding in the normalized image. Conventional rotation resistant schemes that use full frame transform. In this paper we adopt DCT and calculate masking using a spatio-frequency localization of the $8{\times}8$ block DCT coefficients. Experimental results show that the proposed algorithm is robust against rotation process.

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Robust Feature Normalization Scheme Using Separated Eigenspace in Noisy Environments (분리된 고유공간을 이용한 잡음환경에 강인한 특징 정규화 기법)

  • Lee Yoonjae;Ko Hanseok
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.4
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    • pp.210-216
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    • 2005
  • We Propose a new feature normalization scheme based on eigenspace for achieving robust speech recognition. In general, mean and variance normalization (MVN) is Performed in cepstral domain. However, another MVN approach using eigenspace was recently introduced. in that the eigenspace normalization Procedure Performs normalization in a single eigenspace. This Procedure consists of linear PCA matrix feature transformation followed by mean and variance normalization of the transformed cepstral feature. In this method. 39 dimensional feature distribution is represented using only a single eigenspace. However it is observed to be insufficient to represent all data distribution using only a sin91e eigenvector. For more specific representation. we apply unique na independent eigenspaces to cepstra, delta and delta-delta cepstra respectively in this Paper. We also normalize training data in eigenspace and get the model from the normalized training data. Finally. a feature space rotation procedure is introduced to reduce the mismatch of training and test data distribution in noisy condition. As a result, we obtained a substantial recognition improvement over the basic eigenspace normalization.

The Performance Improvement of Edge Histogram Descriptor Image Matching using Image Normalization (이미지 정규화를 이용한 Edge Histogram Descriptor 이미지 매칭 성능 개선)

  • Jo, Min-Hyuk;Lee, Sang-Geol;Cho, Jae-Hyun;Cha, Eui-Young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.385-388
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    • 2013
  • In this paper, we show the weakness of the image matching method by using MPEG-7 EHD(Edge Histogram Descriptor) and suggest how to improve this weakness by using image normalization. EHD algorithm is an image matching technique that collects edge's slope of distribution and same distribution. However, the EHD error rate is high because EHD is sensitive for changes of object distortion and rotation that will be matched. We improve matching performance by accurately extract edge information in image by using normalization. We compare and analyze the normalized EHD algorithm by using distortion and rotation and it shows robustness for changes of the size and rotation.

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A Comparison on the Image Normalizations for Image Information Estimation

  • Kang, Hwan-Il;Lim, Seung-Chul;Kim, Kab-Il;Son, Young-I
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.2385-2388
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    • 2005
  • In this paper, we propose the estimation method for the image affine information for computer vision. The first estimation method is given based on the XYS image normalization and the second estimation method is based on the image normalization by Pei and Lin. The XYS normalization method turns out to have better performance than the method by Pei and Lin. In addition, we show that rotation and aspect ratio information can be obtained using the central moments of both the original image and the sensed image. Finally, we propose the modified version of the normalization method so that we may control the size of the image.

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An intelligent system for isomorphic transformation pattern recognition

  • Xie, Qiusheng;Kobayashi, Akira
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10b
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    • pp.939-944
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    • 1990
  • To recognize isomorphic transformation patterns, such as scale-change, translation and rotation transformed patterns, is an old difficult but interesting problem. Many researches have been done with a dominant approach of normalization by many eminent pioneers. However, there seems no a perfect system which can even recognize 90 .deg.-multiple rotation isomorphic transformation patterns for real needs. Here, as a new challenge, we propose a method of how to recognize 90 .deg.-multiple rotation isomorphic and symmetry isomorphic transformation patterns.

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Affine-Invariant Image normalization for Log-Polar Images using Momentums

  • Son, Young-Ho;You, Bum-Jae;Oh, Sang-Rok;Park, Gwi-Tae
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1140-1145
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    • 2003
  • Image normalization is one of the important areas in pattern recognition. Also, log-polar images are useful in the sense that their image data size is reduced dramatically comparing with conventional images and it is possible to develop faster pattern recognition algorithms. Especially, the log-polar image is very similar with the structure of human eyes. However, there are almost no researches on pattern recognition using the log-polar images while a number of researches on visual tracking have been executed. We propose an image normalization technique of log-polar images using momentums applicable for affine-invariant pattern recognition. We handle basic distortions of an image including translation, rotation, scaling, and skew of a log-polar image. The algorithm is experimented in a PC-based real-time vision system successfully.

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A Rotation Resistant Logo Embedding Watermark on Frequency Domain (회전 변환에 강인한 주파수 영역 로고 삽입 워터마크 방법)

  • Lee, In-Jung;Lee, Hyoung;Min, Joon-Young
    • Proceedings of the Korea Society of Information Technology Applications Conference
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    • 2006.06a
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    • pp.730-736
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    • 2006
  • In this paper, we propose a rotation resistant robust logo embedding watermarking technique. Geometric manipulations make the detection process very complex and difficult. Watermark embedding ill the normalized image directly suffers from smoothing effect due to the interpolation during the image normalization. This can be avoided by estimating the transform parameters using image normalization technique, instead of embedding in the normalized image. Conventional rotation resistant schemes that use full frame transform. In this paper, we adopt $8{\times}8$ block DCT and calculate masking using a spatio-frequency localization of the $8{\times}8$ block DCT coefficients. Experimental results show that the proposed algorithm is robust against rotation process.

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Image Similarity Retrieval using an Scale and Rotation Invariant Region Feature (크기 및 회전 불변 영역 특징을 이용한 이미지 유사성 검색)

  • Yu, Seung-Hoon;Kim, Hyun-Soo;Lee, Seok-Lyong;Lim, Myung-Kwan;Kim, Deok-Hwan
    • Journal of KIISE:Databases
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    • v.36 no.6
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    • pp.446-454
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    • 2009
  • Among various region detector and shape feature extraction method, MSER(Maximally Stable Extremal Region) and SIFT and its variant methods are popularly used in computer vision application. However, since SIFT is sensitive to the illumination change and MSER is sensitive to the scale change, it is not easy to apply the image similarity retrieval. In this paper, we present a Scale and Rotation Invariant Region Feature(SRIRF) descriptor using scale pyramid, MSER and affine normalization. The proposed SRIRF method is robust to scale, rotation, illumination change of image since it uses the affine normalization and the scale pyramid. We have tested the SRIRF method on various images. Experimental results demonstrate that the retrieval performance of the SRIRF method is about 20%, 38%, 11%, 24% better than those of traditional SIFT, PCA-SIFT, CE-SIFT and SURF, respectively.

An Analytical and Experimental Study of Binary Image Normalization for Scale Invariance with Zernike Moments

  • Kim, Whoi-Yul
    • Journal of Electrical Engineering and information Science
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    • v.2 no.6
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    • pp.146-155
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    • 1997
  • In order to achieve scale- and rotation-invariance in recognizing unoccluded objects in binary images using Zernike moment features, an image of an object has often been normalized first by its zeroth-order moment (ZOM) or area. With elongated objects such as characters, a stroke width varies with the threshold value used, it becomes one or two pixels wider or thinner. The variations of the total area of the character becomes significant when the character is relatively thin with respect to its overall size, and the resulting normalized moment features are no longer reliable. This dilation/erosion effect is more severe when the object is not focused precisely. In this paper, we analyze the ZOM method and propose as a normalization method, the maximum enclosing circle (MEC) centered at the centroid of the character. We compare both the ZOM and MEC methods in their performance through various experiments.

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