• Journal of Multimedia Information System
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• v.4 no.4
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• pp.249-254
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• 2017

Digital vector maps must be compressed effectively for transmission or storage in Web GIS (geographic information system) and mobile GIS applications. This paper presents a polyline compression method that consists of polyline feature-based hybrid simplification and second derivative-based data compression. Experimental results verify that our method has higher simplification and compression efficiency than conventional methods and produces good quality compressed maps.

• Journal of Korea Multimedia Society
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• v.16 no.4
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• pp.418-429
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• 2013

This paper presents a GIS vector map data compression scheme based on hybrid polyline simplification method and SEC(spatial energy compaction). The proposed method extracts all layers which contain polylines in the GIS vector map and compress all polylines in extracted layers by the hybrid polyline simplification and SEC based on MAE(minimum area error) for each segment in the line. The proposed simplification and SEC increase the compression ratio while preserving the shape quality. We analyze the visual aspects and compression efficiency between the original GIS vector map and the compressed map. From experimental results, we verify that our method has the higher compression efficiency and visual quality than conventional methods.

• Journal of Korea Multimedia Society
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• v.19 no.8
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• pp.1453-1459
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• 2016

Recently, vector map has developed, used in many domains, and in most cases vector map data contains confidential information which must be kept away from unauthorized users. Moreover, the manufacturing process of a vector map is complex and the maintenance of a digital map requires substantial monetary and human resources. This paper presents the selective encryption scheme based on polyline simplification methods for GIS vector map data protection to store, transmit or distribute to authorized users. Main advantages of our algorithm are random vertices and transformation processes but it still meets requirements of security by random processes, and this algorithm can be implement to many types of vector map formats.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.167-170
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• 2005

In the mobile environments for the vector map services, a map simplification work through the map generalization steps helps improve the readability of the map on a large scale. The generalization operations are various such as selection, aggregation, simplification, displacement, and so on, the formal operation algorithms have not been built yet. Because the algorithms require deep special knowledge and heuristic, which make it hard to automate the processes. This thesis proposes some map generalization algorithms specialized in mobile vector map services, based on previous works. We will show the detail to adapt the approaches on the mobile environment, to display complex spatial objects efficiently on the mobile devices which have restriction on the resources

• Journal of information and communication convergence engineering
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• v.6 no.2
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• pp.187-191
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• 2008

In the mobile environments for the vector map services, a map simplification work through the map generalization steps helps improve the readability of the map on a large scale. The generalization operations are various such as selection, aggregation, simplification, displacement, and so on, the formal operation algorithms have not been built yet. Because the algorithms require deep special knowledge and heuristic, which make it hard to automate the processes. This thesis proposes some map generalization algorithms specialized in mobile vector map services, based on previous works. This thesis will show the detail to adapt the approaches on the mobile environment, to display complex spatial objects efficiently on the mobile devices which have restriction on the resources.

• Journal of Korea Multimedia Society
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• v.18 no.3
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• pp.298-311
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• 2015

Vector data represents a map by its coordinate and Raster data represents a map by its pixel. Since these data types have very large data size, data compression procedure is a compulsory process. This paper compare the results from three different methodologies; GIS (Geographic Information System) vector map data compression using DP(Douglas-Peucker) Simplification algorithm, vector data compression based on Bin classification and the combination between two previous methods. The results shows that the combination between the two methods have the best performance among the three tested methods. The proposed method can achieve 4-9% compression ratio while the other methods show a lower performance.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.464-467
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• 2003

There are two approaches to construct mobile GIS, Vector and Raster methods, according to the map data transformation format from server to mobile client. Each method requires a different implementation architecture of server and client modules for mobile map services. And each have advantages and disadvantages at the different aspects. This thesis implements these two approaches, thus, compares the each merits, by experiments. They include the transmission performance, map quality, and so on.

• Spatial Information Research
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• v.15 no.4
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• pp.385-395
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• 2007

As the growth of performance of the computer and the development of the Internet are exponential, sharing and using the information illegally have also increased to the same proportion. In this paper, we proposed a novel method on the vector map data among digital contents. Vector map data are used for GIS, navigation and web-based services etc. We embedded watermark into the coordinate of the vector map data using bit operation and extracted the watermark. This method helps to protect the copyright of the vector map data. This watermarking method is a spatial domain method and it embeds the watermark within an allowable error. Our experiment shows that the watermark produced by this method is resistant to simplification and translation.

• The KIPS Transactions:PartD
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• v.9D no.5
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• pp.819-826
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• 2002

The mobile vector map services for mobile devices, specially for PDA, are being popularized with the advent of KVM (Kilobytes Virtual Machine). However, the services for cellular phone have some problems for implementation, which are the restrictions of bandwidth, resource of the phone, etc. Thus, these restrictions force to develop new map database exclusively for cellular phone services. But, this approach needs high costs and could not support multi user view for a same area. Therefore, we suggest new client/server system for mobile vector map services, using existing general map database, and design and implement the system. The suggested system, which has minimized functions at client and processes map simplification works at sever, makes it possible to serve mobile vector map without developing new map database only for cellular phone.

• Proceedings of the Korea Multimedia Society Conference
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• 2012.05a
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• pp.449-450
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• 2012

오늘날 컴퓨터와 정보통신 기술에 의해 생성된 디지털 맵(map)은 다양한 분야에서 응용 활용되고 있다. 이에 디지털 맵 제작 기술의 발전과 함께 선형 단순화(line simplification) 기법에 대한 연구가 활발하게 진행되고 있다. 이에 본 논문은 라인의 형상을 최대한 보존하기 위하여 최소영역오차(minimum area error, MAE) 구간을 이용한 혼합형 선형 단순화 기법을 제안한다. 기존의 선형 단순화 기법과의 비교 실험을 통하여, 제안하는 기법의 성능이 우수함을 확인하였다.