• 제목/요약/키워드: matching quality

Search Result 599, Processing Time 0.027 seconds

Fast PDE Algorithm Using Block Matching Error Prediction (블록 정합오차 예측을 이용한 고속 PDE 알고리즘)

  • Sin, Se-Ill;Oh, Jeong-Su
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.32 no.4C
    • /
    • pp.396-400
    • /
    • 2007
  • This paper proposes the fast partial difference elimination (PDE) algorithm. When the conventional PDE cannot skip the rest of matching procedure in a candidate block using a partial matching error, the proposed algorithm estimates to skip it again using the block matching error predicted from the computed partial matching error. The proposed algorithm can eliminate impossible candidate blocks earlier than the conventional PDE since the predicted block matching error is always bigger than the partial matching error. The simulation results show that the proposed algorithm can significantly reduce the computations while keeping image quality as good as the conventional PDE.

D$^*$Model Matching Control System for Four Wheel Steering

  • Asara, Naoki;Osa, Yasuhiro;Uchikado, Shigeru;Kanai, Kimio
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.670-674
    • /
    • 2005
  • $D^*$ criterion is defined as a reference of the handling quality and ride comfortableness for lateral-directional automobile motion. However it is generally difficult to obtain the satisfied handling quality and ride comfortableness based on $D^*$ criterion by conventional two wheel steering system. In this study, a design method of model matching control system is proposed to obtain the satisfied $D^*$ response of 4 Wheel Steering.

  • PDF

Analysis on Iris Image Degradation Factors (홍채 인식 성능에 영향을 미치는 화질 저하 요인 분석)

  • Yoon, So-Weon;Kim, Jai-Hie
    • Proceedings of the IEEK Conference
    • /
    • 2008.06a
    • /
    • pp.863-864
    • /
    • 2008
  • To predict the iris matching performance and guarantee its reliability, image quality measure prior to matching is desired. An analysis on iris image degradation factors which deteriorate matching performance is a basic step for iris image quality measure. We considered five degradation factors-white-out, black-out, noise, blur, and occlusion by specular reflection-which happen generally during the iris image acquisition process. Experimental results show that noise and white-out degraded the EER most significantly, while others on EER were either insignificant or degradation images resulted in even better performance in some cases of blur. This means that degradation factors that affect the performance can be different from those based on human perception or image degradation evaluation.

  • PDF

Synthesizing Intermediate Images Using Stereoscopic Images

  • Kwak, Ji-Hyun;Komar, V.S.V.;Kim, Kyung-Tae
    • Journal of the Optical Society of Korea
    • /
    • v.6 no.4
    • /
    • pp.143-149
    • /
    • 2002
  • In this paper, we present an algorithm for synthesizing intermediate views from a stereoscopic pair of images. Syntheses of intermediate images allows one to realize a more comfortable the 3D display system. The proposed method is based on block matching, which is not ordinarily used. The contour information is used for a block decision. In order to find an equivalent (or corresponding) block, there are two steps: "matching of contour-to-original image" and "matching of contour-to-contour image" methods. "Matching of contour-to-contour image" uses both left and right contour images. This block matching method allows us to find the corresponding block in spite of different block sizes. Experimental results illustrate the performance of the proposed technique and we obtained a high quality image of more than 31 dB PSNR.image of more than 31 dB PSNR.

A Robust Fingerprint Matching System Using Orientation Features

  • Kumar, Ravinder;Chandra, Pravin;Hanmandlu, Madasu
    • Journal of Information Processing Systems
    • /
    • v.12 no.1
    • /
    • pp.83-99
    • /
    • 2016
  • The latest research on the image-based fingerprint matching approaches indicates that they are less complex than the minutiae-based approaches when it comes to dealing with low quality images. Most of the approaches in the literature are not robust to fingerprint rotation and translation. In this paper, we develop a robust fingerprint matching system by extracting the circular region of interest (ROI) of a radius of 50 pixels centered at the core point. Maximizing their orientation correlation aligns two fingerprints that are to be matched. The modified Euclidean distance computed between the extracted orientation features of the sample and query images is used for matching. Extensive experiments were conducted over four benchmark fingerprint datasets of FVC2002 and two other proprietary databases of RFVC 2002 and the AITDB. The experimental results show the superiority of our proposed method over the well-known image-based approaches in the literature.

A Spectral Smoothing Algorithm for Unit Concatenating Speech Synthesis (코퍼스 기반 음성합성기를 위한 합성단위 경계 스펙트럼 평탄화 알고리즘)

  • Kim Sang-Jin;Jang Kyung Ae;Hahn Minsoo
    • MALSORI
    • /
    • no.56
    • /
    • pp.225-235
    • /
    • 2005
  • Speech unit concatenation with a large database is presently the most popular method for speech synthesis. In this approach, the mismatches at the unit boundaries are unavoidable and become one of the reasons for quality degradation. This paper proposes an algorithm to reduce undesired discontinuities between the subsequent units. Optimal matching points are calculated in two steps. Firstly, the fullback-Leibler distance measurement is utilized for the spectral matching, then the unit sliding and the overlap windowing are used for the waveform matching. The proposed algorithm is implemented for the corpus-based unit concatenating Korean text-to-speech system that has an automatically labeled database. Experimental results show that our algorithm is fairly better than the raw concatenation or the overlap smoothing method.

  • PDF

Adaptive Matching Scan Algorithm Based on Gradient Magnitude and Sub-blocks in Fast Motion Estimation of Full Search (전영역 탐색의 고속 움직임 예측에서 기울기 크기와 부 블록을 이용한 적응 매칭 스캔 알고리즘)

  • 김종남;최태선
    • Proceedings of the IEEK Conference
    • /
    • 1999.11a
    • /
    • pp.1097-1100
    • /
    • 1999
  • Due to the significant computation of full search in motion estimation, extensive research in fast motion estimation algorithms has been carried out. However, most of the algorithms have the degradation in predicted images compared with the full search algorithm. To reduce an amount of significant computation while keeping the same prediction quality of the full search, we propose a fast block-matching algorithm based on gradient magnitude of reference block without any degradation of predicted image. By using Taylor series expansion, we show that the block matching errors between reference block and candidate block are proportional to the gradient magnitude of matching block. With the derived result, we propose fast full search algorithm with adaptively determined scan direction in the block matching. Experimentally, our proposed algorithm is very efficient in terms of computational speedup and has the smallest computation among all the conventional full search algorithms. Therefore, our algorithm is useful in VLSI implementation of video encoder requiring real-time application.

  • PDF

Fractal Coding of Three Dimensional Medical Images with Perceptually Enhanced Matching (삼차원 의학 영상에서 시각적으로 향상된 정합을 사용한 프랙탈 부호화)

  • Ahn, C.B;Song, Y.C;Shin, H.S
    • Journal of Biomedical Engineering Research
    • /
    • v.17 no.3
    • /
    • pp.305-312
    • /
    • 1996
  • A new three dimensional fractal coding is proposed with a perceptually enhanced matching. Since most of medical images (e.g. computed tomoyaphy or magnetic resonance images) have three dimensional characters, searching regions are extended to adjacent slices. For a perceptually enhanced matching, a high frequency boost filter is used for pre-filtering images to be encoded, and a least mean square error matching is applied to the edge enhanced Images rather than the original images. From simulation with magnetic resonance images($255\times255$, 8bits/pixel), reconstructed images by the proposed compression algorithm show much improved subjective image quality with higher peak signnal-to-noise ratio compared to those by existing fractal coding algorithms at compression ratios of about 10.

  • PDF

A Probabilistic Dissimilarity Matching for the DFT-Domain Image Hashing

  • Seo, Jin S.;Jo, Myung-Suk
    • International Journal of Advanced Culture Technology
    • /
    • v.5 no.1
    • /
    • pp.76-82
    • /
    • 2017
  • An image hash, a discriminative and robust summary of an image, should be robust against quality-preserving signal processing steps, while being pairwise independent for perceptually different inputs. In order to improve the hash matching performance, this paper proposes a probabilistic dissimilarity matching. Instead of extracting the binary hash from the query image, we compute the probability that the intermediate hash vector of the query image belongs to each quantization bin, which is referred to as soft quantization binning. The probability is used as a weight in comparing the binary hash of the query with that stored in a database. A performance evaluation over sets of image distortions shows that the proposed probabilistic matching method effectively improves the hash matching performance as compared with the conventional Hamming distance.

Case-Based Reasoning Cost Estimation Model Using Two-Step Retrieval Method

  • Lee, Hyun-Soo;Seong, Ki-Hoon;Park, Moon-Seo;Ji, Sae-Hyun;Kim, Soo-Young
    • Land and Housing Review
    • /
    • v.1 no.1
    • /
    • pp.1-7
    • /
    • 2010
  • Case-based reasoning (CBR) method can make estimators understand the estimation process more clearly. Thus, CBR is widely used as a methodology for cost estimation. In CBR, the quality of case retrieval affects the relevance of retrieved cases and hence the overall quality of the reminding capability of CBR system. Thus, it is essential to retrieve relevant past cases for establishing a robust CBR system. Case retrieval needs the following tasks to obtain appropriate case(s); indexing, search, and matching (Aamodt and Plaza 1994). However, the previous CBR researches mostly deal with matching process that has limits such as accuracy and efficiency of case retrieval. In order to address this issue, this research presents a CBR cost model for building projects that has two-step retrieval process: decision tree and nearest neighbor methods. Specifically, the proposed cost model has indexing, search and matching modules. Features in the model are divided into shape-based and scale-based attributes. Based on these, decision tree is established for facilitating the search task and nearest neighbor method was utilized for matching task. In regard to applying nearest neighbor method, attribute weights are assigned using GA optimization and similarity is calculated using the principle of distance measuring. Thereafter, the proposed CBR cost model is developed using 174 cases and validated using 12 test cases.