• Title/Summary/Keyword: resizing

Search Result 143, Processing Time 0.027 seconds

A Survey on Content Aware Image Resizing Methods

  • Garg, Ankit;Negi, Ashish
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.14 no.7
    • /
    • pp.2997-3017
    • /
    • 2020
  • With the advancement in the field of image processing, images are being processed using various image processing algorithms. Nowadays, many efficient content-aware image resizing techniques are being used to safeguard the prominent regions and to generate better results that are visually appealing and pleasing while resizing. Advancements in the new display device with varying screen size demands the development of efficient image resizing algorithm. This paper presents a survey on various image retargeting methods, comparison of image retargeting results based on performance, and also exposes the main challenges in image retargeting such as content preservation of important regions, distortion minimization, and improving the efficiency of image retargeting methods. After reviewing literature from researchers it is suggested that the use of the single operator in image retargeting such as scaling, cropping, seam carving, and warping is not sufficient for obtaining satisfactory results, hence it is essential to combine multiple image retargeting operators. This survey is useful for the researchers interested in content-aware image retargeting.

Stiffness Design Method of Steel Structures using Resizing Techniques (재분배기법을 이용한 강구조물의 강성설계법)

  • Ahn, Sun A;Park, Hyo Seon
    • Journal of Korean Society of Steel Construction
    • /
    • v.10 no.1 s.34
    • /
    • pp.63-72
    • /
    • 1998
  • The stiffness design method is presented as a drift control model of steel structures and applied to design of space trusses subjected to stress and displacement constraints. The stiffness design method is developed by integrating the resizing techniques for an effective drift control algorithm with the strength design process according to the commonly used design specifications such as allowable stress design. In the resizing technique the amount of material to be modified depends on the member displacement participation factors and is determined by an optimization technique. Using the stiffness design method, a structural design model for steel structures is proposed and applied to two verifying examples. As demonstrated in the examples, the displacement of the structures can be effectively controlled without expensive computational cost.

  • PDF

Development of the Drift Design Method of High-rise Buildings using Weight Control Factors (중량 조절계수를 이용한 고층 건물 변위설계법 개발)

  • Park, Hyo Seon;Seo, Ji Hyun
    • Journal of Korean Society of Steel Construction
    • /
    • v.17 no.3 s.76
    • /
    • pp.285-294
    • /
    • 2005
  • Drift design is one of the core techniques in the structural design of high-rise buildings and resizing technique is regarded as a practical drift design method for high-rise buildings. In the resizing technique, the structural weight is re-distributed to minimize the target displacement without a change in structural weights. However, the structural weight determined from resizing algorithm is bound to the structural weight based on the preliminary design. Therefore, in this paper, a drift design method that can control the weight of the structure without causing drift control performance to deteriorate is proposed by incorporating the weight control factor in the formulation of resizing algorithm. The proposed drift design method is applied to the drift design of two frame-shear wall systems. The proposed drift design method, in this study, makes it possible to control both the drift and weight of a high-rise building.

Development of Resizing Techniques for Drift Designs of High-rise Buildings subjected to Lateral and Vertical Loads (횡하중과 연직하중을 받는 고층건물의 변위설계를 위한 재분배기법 개발)

  • 서지현;박효선
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.17 no.1
    • /
    • pp.49-58
    • /
    • 2004
  • Drift design of a high-rise building is a governing factor in the determination of structural weights and lateral resisting systems. However, high-rise buildings are composed of tens of thousands of structural member, designer can not know which members are active to lateral drift control and how much they contribute to lateral drifts. Resizing technique was proved to be a practical method for drift design of high-rise buildings. However, no resizing algorithm has been considered the effect of vertical loads in drift designs. Thus, in this paper, a resizing algorithm has been developed for drift designs of high-rise buildings subjected to both lateral and vertical loads. The drift design model has been applied to drift designs of two high-rise building examples.

Lateral Drift Control and Resizing Technique for Tall Buildings using Lateral-Stiffness Influence Matrix (횡강성 영향행렬을 이용한 고층건물의 횡변위 제어 및 단면 재산정 방안)

  • 이한주;김치경;김호수
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.15 no.2
    • /
    • pp.271-279
    • /
    • 2002
  • This study develops the module to find the lateral stiffness influence matrix of each story and performs the displacement sensitivity analysis by virtual load method for the efficiency of optimal design using lateral stiffness influence matrix. Also, resizing technique based on the estimated lateral stiffness increment factors is developed to apply directly the results of optimal design. To this end, resizing technique is divided into the continuous and discrete section design methods. And then the relationships between section properties and section size are established. Specifically, an initial design under strength constraints is first performed, and then the lateral load resistant system is designed to control lateral displacements yet exceeding the drift criteria. Two types of 45-story three dimensional structures we presented to illustrate the features of the lateral drift control and resizing technique for tall buildings proposed in this study.

New Algorithm for Arbitrary-ratio Image Resizing in DCT Domain (DCT 영역에서 영상의 임의 비율 크기 변환을 위한 새로운 알고리즘)

  • Kim, Yong-Jae;Lee, Chang-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.32 no.2C
    • /
    • pp.113-123
    • /
    • 2007
  • In Ubiquitous communication environment, various conversions of images are essential, and most digital images are compressed by standard methods such as the Joint Photographic Expert Group (JPEG) and Motion Picture Expert Group (MPEG) which are based on the discrete cosine transform (DCT). In this paper, various image resizing algorithms in the DCT domain are analyzed, and a new image resizing algorithm, which shows superior performance compared with the conventional methods, is proposed. For arbitrary-ratio image resizing in the DCT domain, several blocks of $8{\times}8$ DCT coefficients are converted into one block using the conversion formula in the proposed algorithm, and the size of the inverse discrete cosine transform (IDCT) is decided optimally. The performance is analyzed by comparing the peak signal to noise ratio (PSNR) between original images and converted images. The performance of the proposed algorithm is better than that of the conventional algorithm, since the correlation of pixels in images is utilized more efficiently.

Development of Drift Design Method of High-rise buildings considering Material Properties of Shear Walls and Design Variable Linking Strategy (RC 전단벽의 재료 물성과 부재 그룹핑을 고려한 고층건물 변위조절설계법 개발)

  • 서지현;박효선
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2004.04a
    • /
    • pp.487-494
    • /
    • 2004
  • Resizing techniques have been recognized as practical methods for drift design of high-rise building since sensitivity analysis and iterative structural analysis are not required in implementation. In the techniques, the amount of material of a memberin a building for resizing is determined in terms of cross-sectional areas and sectional inertia moments as design variables. In this study, five drift design methods are developed by considering design variable linking strategy and fomulating resizing algorithm in terms of material properties of shear walls as a design variable. The developed methods are applied to the drift design of 20-story frame-RC shear wall structure, and then evaluated in the view points of practicality and efficiency.

  • PDF

Research for Bit-depth Conversion Development by Detection Lost Information to Resizing Process for Digital Photography (디지털 사진영상의 크기조절과정에서 유실되는 정보를 이용한 비트심도의 확장)

  • Cho, Do-Hee;Maik, Vivek;Paik, Joon-Ki;Har, Dong-Hwan
    • The Journal of the Korea Contents Association
    • /
    • v.9 no.4
    • /
    • pp.189-197
    • /
    • 2009
  • A digital image usually has 8 bits of depth basically representing pixel intensity ranging for [0 255]. These pixel range allow 256 step levels of pixel values in the image. Thus the greyscale value for a given image is an integer. When we carry out interpolation of a given image for resizing we have to round the interpolated value to integer which can result in loss of quality on perceived color values. This paper proposes a new method for recovering this loss of information during interpolation process. By using the proposed method the pixels tend to regain more original values which yields better looking images on resizing.

Transform Domain Resizing for DCT-Based Codec (DCT 코덱에 기반한 변환 영역에서의 리사이징 알고리즘)

  • 신건식;장준영;강문기
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.41 no.3
    • /
    • pp.25-34
    • /
    • 2004
  • The ability to perform the same operations in the transform domain as in the spatial domain is important for efficient image transmission through a channel. We perform image resizing, which includes magnifying and reducing the size, in the discrete cosine transform(DCT) domain and the effects of the transform domain approach are analyzed in the corresponding spatial domain. Based on this analysis, the two resizing algorithms are proposed. The first one further compresses the images encoded by the compression standard by reducing the size before compression, and the other reduces the loss of information while maintaining the conventional compression rate. Because of its compatibility with standard codec, these algorithms can be easily embedded in JPEG and MPEG codecs, which are widely used for the purpose of image storage and transmission. Experimental results show a reduction of about half the bit size with similar image quality and about a 2- or 3-dB quality improvements in the similar compression rate.

Design Method to Control Wind-Induced Vibration of High-Rise Buildings Using Resizing Algorithm (재분배기법을 이용한 고층건물의 풍응답 가속도 조절 설계기법)

  • Seo, Ji-Hyun;Park, Hyo-Seon
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.23 no.5
    • /
    • pp.465-473
    • /
    • 2010
  • As increase of height and slenderness of buildings, serviceability design criteria such as maximum lateral drift and wind-induced vibration level play an important role in structural design of high-rise buildings. Especially, wind-induced vibration is directly related to discomfort of occupants. However, no practical algorithm or design method is available for structural designers to control the acceleration level due to wind. This paper presented a control method for wind-induced vibration of high-rise buildings using the resizing algorithm. The level of vibration due to wind is calculated by well known estimation rules of ASCE 7-02, NBCC 95, SAA83, and Solari method. Based on the fact that the level of wind-induced vibration is inversely proportional to the magnitude of natural periods of buildings, in the design method, natural periods of a high-rise building are modified by redistribution of structural weight according to the resizing algorithm. The design method is applied to wind-induced vibration control design of real 42-story residential building and evaluated the efficiency and effectiveness.