2017 , Vol. 19 >Issue 9: 1245 - 1252

CONTENTS

Generation of Variable-Scale Route Maps with Consideration of Distortion Reduction for Small Display Sizes

• WANG Liying ,
• TI Peng , * ,
• YU Chonghu ,
• ZHAO Dongxu ,
• HOU Xiaotong
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• Faculty of Geosciences and Environmental Engineering, State-province Joint Engineering Laboratory of Spatial Information Technology for High-speed Railway Safety, Southwest Jiaotong University, Chengdu 611756, China
*Corresponding author: TI Peng, E-mail:

Request revised date: 2017-07-15

Online published: 2017-10-09

《地球信息科学学报》编辑部 所有

### Abstract

Currently route maps are often displayed on mobile devices for the route selection. However, for such devices, a major problem is their small display sizes. In this study, a new method on adaptive generation of variable scale maps for small display sizes was proposed and aimed to improve the clarity of the whole map. This method consists of two steps, i.e. estimating the density of global distribution on maps and conducting variable scale transformation based on the estimated density values. Compared with current variable scale methods, this method considered the space for representation of the landmarks and text symbols, and the reduction of overall distortions arising from map deformation. The experimental results indicated that the new method is able to adaptively generate the variable scale maps for different small display sizes and provide a map overview with an improved clarity as well as well-preserved map recognition compared with original shapes.

WANG Liying , TI Peng , YU Chonghu , ZHAO Dongxu , HOU Xiaotong . Generation of Variable-Scale Route Maps with Consideration of Distortion Reduction for Small Display Sizes[J]. Journal of Geo-information Science, 2017 , 19(9) : 1245 -1252 .

### 2 变比例尺路线图生成方法

#### 2.1 顾及注记符号的密度分布估计

$D = N A$ （1）

#### 2.2 基于密度分布的变比例尺变换

$u min ≤ x i ≤ u max v min ≤ y i ≤ v max$ （2）

$S ix ≥ u x ∙ D i S iy ≥ u y ∙ D i$ （3）

$d x ij = S ix ∙ ( X i - X j ) - ( x i - x j ) d y ij = S iy ∙ ( Y i - Y j ) - ( y i - y j )$ （4）

$Minimize （ e 1 + w e 2 ）$ （7）

### 4 总结

The authors have declared that no competing interests exist.

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