23/08/2011

* Acquisition of secondary data from OpenStreetMap


Perolehan data sekunder oleh OpenStreetMap

Sering pengguna GIS dihimpit pelbagai masalah bila hendak mendapatkan data dari pihak custodian. Walaupun pihak custodian boleh meluluskan permohonan data, isu tambahan pula adalah proses mendapatkan data mungkin mengambil masa panjang dan yang boleh menjejaskan dateline. Untuk menyulitkan semua ni,  mungkin pemohon juga akan dikenakan bayaran. Jadi bagaimana pengguna GIS hendak mendapatkan data dengan masa singkat bagi tujuan kegunaan projek tetapi dihadapi dengan bajet  yang amat terhad? Jangan panik kawan-kawan! Alternatifnya adalah sumber Internet dan termasuk sumber Google, Yahoo, Bing dan Wikimapia. Bagaimanapun data-data tersebut hanya dapat dicapai dalam mode view dan tidak dibenarkan muat turun data. Godek-godek-godek QGIS, terdapatnya satu modul yang membolehkan muat turun data secara percuma dan tidak salah dari segi undang-undang iaitu OpenStreetMap. Data OpenStreetMap merupakan hasil sumbangan komuniti dunia dan sentiasa dikemaskini oleh penyumbang-penyumbang yang menggunakan modul tersebut. Apa yang perlu dibuat cuma melibatkan pengguna mengaktifkan OpenStreetMap. Saya lebih berminat mula-mula membuka OpenLayers and memilih salah satu Google Maps sama ada Google Satellite atau Google Hybrid kerana lebih puashati dan biasa dengan Google Maps lalu menggunakan OpenStreetMap cuma bagi tujuan memuat turun data. Mudah dan cepat. Bergantung kepada usaha penyumbang-penyumbang, data yang dimuat turun dapat diperolehi dalam bentuk point, polygon dan line untuk membolehkan analisis GIS selanjutnya!

Acquisition of secondary data from OpenStreetMaps

Often is the user face with various problems when trying to obtain data from the data custodian. Eventhough the data custodian can approve the request for data acquisition, additional issues include the process in obtaining that data may be time -consuming and can affect datelines. To make matters more difficult, it may involve cost. How does a GIS user acquire data in a short time for project purposes coupled with a limited budget? Don't panic friend! The alternative is to source  the Internet such as Google, Yahoo, Bing and Wikimapia. However these data can only be viewed but not downloaded. Tinkering with QGIS, it was found that a module that can download free and legally is OpenStreetMap. OpenStreetMap data represents  the international community contribution and is always updated by contributors whom use that module. What is needed is for the user to activate OpenStreetMap. At first I was interested activating OpenLayers and choosing either Google Maps or Google Satellite or Google Hybrid because I was more satisfied and usually Google Maps can be viewed through OpenStreetMap for downloading purposes. Simple and fast. Depending on the efforts of contributors, the downloaded data can be acquired in point, polygon and line for further GIS analysis.

8 comments:

  1. Hello Mr Abbas, good to see someone actively promoting GIS in Malaysia. I am an OSM mapper and I am happy to see you promoting OSM in your lecture. QGIS has the OSM mapping tools too so hopefully more people will participate in mapping Malaysia. Cheers :)

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    1. You will surprised to know that eyes pop out and faces start to grin when I show and teach QGIS users how to use OSM. While many know of Google maps, all are surprised that such a thing as OSM exist to the point that GIS features are downloadable. I explain this is Open Source community where knowledge-sharing is important and I can also see confused looks probably a mindset moulded from much use of proprietary GIS.

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    2. One of my fellow OSM mapper wants to map the KL boundary. Do you know if he can get the boundary coordinates in digital format (shp/dxf) from any government department ? or are there any government agencies willing to contribute to Open source maps ?

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    3. The right authority is of course Kuala Lumpur City Council(DBKL). Their web site is www.dbkl.gov.my. Whilst it is in Malay language, there are contact details at the bottom right hand corner. Ask for the Director of the Town Planning Department.

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  2. Encik Abbas,
    I happen to spot your blog here upon looking for GIS vocational 1 day placement opportunities in Novemberfor a young professional from Australia who is a 3D spatial data officer and i think you may be able to assist me. How can I contact you?
    S.Suhaimi

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    1. Email me at abbas.abdulwahab@gmail.com. Firstly, I do not know whether I can what you ask of me but there is no harm in trying. Insyallah, together we can.

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