Development of free and open source software for flow mapping integrated to geographic information systems

Download

index.pdf

Date

2014

Author

Güllüoğlu, Naim Cem

Metadata

Show full item record

Item Usage Stats

363
views

160
downloads

Mapping of spatial interaction data is an ongoing challenge for cartographers. In many Geographic Information Systems (GIS) software there is no off-the-shelf functionality for processing and visualizing spatial interactions or geographical flows. Considering the development efforts that have been made in the last few decades to discover the potential of GIS almost in every aspect, handling and visualization of spatial interaction data under GIS remain underutilized. The main objective of this study is to develop a general purpose free and open source software for flow mapping that is fully integrated to a desktop GIS application. Identified as the most fundamental form of geographical flows, the scope of this study focuses on exploration and visualization of interactions taking place between geographic locations where the actual flow routes are unknown or negligible. The flow mapping software, FlowMapper, is designed as a plugin to the popular, free and open source Geographic Information Systems software Quantum GIS (QGIS). Development environment tools utilized in this study consists of Python programming language, PyQGIS Python bindings for QGIS API, PyQt Python bindings for Qt framework, Qt Designer tool and OGR Simple Feature Library. Designed as a fully menu driven and user friendly plugin, users of FlowMapper are capable of generating flow maps easily by supplying node coordinates and interaction matrix. Besides, flow related attributes such as net, gross magnitude calculations are automatically performed and flow gaining, flow losing nodes are automatically identified. In order to increase cartographic quality, advanced symbology options and flow filtering capabilities are also offered in FlowMapper as spatially non-distorting visual clutter reduction techniques. Capabilities of developed plugin are successfully tested with different scenarios and by using several flow datasets consisting of four to two hundred nodes. Comprising of more than 6.500 lines of code, FlowMapper plugin received more than ten thousand downloads during two years of development period. Besides, plugin website received visitors from more than eighty countries. These indicators prove the need for integration of flow mapping tools to popular, open source desktop GIS applications. The main contribution of this study is the free and open source, general purpose flow mapping application FlowMapper which is integrated to QGIS in plugin form that aids exploration of spatial interaction data and creation of flows maps with symbology and filtering options.

Subject Keywords

Geographic information systems., Cartography, Remote-sensing images., Image processing., Image processing

URI

http://etd.lib.metu.edu.tr/upload/12617785/index.pdf
https://hdl.handle.net/11511/23800

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

An integrated approach to computational vision - The edge strength function and the nested symmetries Tarı, Zehra Sibel (1999-01-01) A new development in local symmetry extraction and its connections to segmentation functionals and the fronts propagating with curvature-dependent speed are examined. The basic tool is a new distance function that attains its maximum value at the shape boundary and decays rapidly away from there. It is shown that the Hessian of the distance function captures perceptual information that can be extracted easily, efficiently, and robustly in the form of nested local shape symmetries at multiple scales. The mos...
Topological Navigation Algorithm Design and Analysis Using Spherical Images Şahin, Yasin; Koku, Ahmet Buğra; Department of Mechanical Engineering (2022-8-23) A topological navigation algorithm that has the capability of mapping and localization based on visual contents is proposed. Keypoint detection and feature matching are conducted on spherical images to extract significant features among sequential frames. Robot movement direction is estimated based on historical angle differences of significant features to reach the final destination. The navigation process is supported with visual egocentric localization to gain simultaneous localization and mapping compet...
Alignment of uncalibrated images for multi-view classification Arık, Sercan Ömer; Vural, Elif; Frossard, Pascal (2011-12-29) Efficient solutions for the classification of multi-view images can be built on graph-based algorithms when little information is known about the scene or cameras. Such methods typically require a pairwise similarity measure between images, where a common choice is the Euclidean distance. However, the accuracy of the Euclidean distance as a similarity measure is restricted to cases where images are captured from nearby viewpoints. In settings with large transformations and viewpoint changes, alignment of im...
A Shadow based trainable method for building detection in satellite images Dikmen, Mehmet; Halıcı, Uğur; Department of Geodetic and Geographical Information Technologies (2014) The purpose of this thesis is to develop a supervised building detection and extraction algorithm with a shadow based learning method for high-resolution satellite images. First, shadow segments are identified on an over-segmented image, and then neighboring shadow segments are merged by assuming that they are cast by a single building. Next, these shadow regions are used to detect the candidate regions where buildings most likely occur. Together with this information, distance to shadows towards illuminati...
Development of free/libre and open source spatial data analysis system fully coupled with geographic information system Kepoğlu, Volkan Osman; Düzgün, H. Şebnem; Department of Geodetic and Geographical Information Technologies (2011) Spatial Data Analysis (SDA) is relatively narrower and constitutes one of the areas of Spatial Analysis. Geographic Information System (GIS) offers a potentially valuable platform for supporting SDA techniques. Integration of SDA with GIS helps SDA to benefit from the data input, storage, retrieval, data manipulation and display capabilities of GIS. Also, GIS can benefit from SDA techniques in which the integration of these techniques can increase the analysis capabilities of GIS. This integration serves fo...

Citation Formats

N. C. Güllüoğlu, “Development of free and open source software for flow mapping integrated to geographic information systems,” Ph.D. - Doctoral Program, Middle East Technical University, 2014.