SlashGeo links to a website that, like a number of others, offers services to convert graphic images and vector data into Google Maps, Google Earth, and Virtual Earth formats. There’s certainly a niche for services like this, especially if you don’t have a lot of background in working with geographic data. But if you have even a little bit of that background, you can save a lot of money by doing it yourself.
1. Converting PDF files to Microsoft Virtual Earth format requires first converting them to a graphic format like JPG or TIF, which you can do with for free with PDFCreator. Next you have to georeference them, assigning coordinates to the individual pixels in the image. I’ll be covering a number of free ways to do that in the future, but for now, it’s enough to say that you can georeference and image with the free GIS program MapWindow, or with MicroDEM. Finally, to convert the georeferenced image to Virtual Earth format, you can use Microsoft’s free MapCruncher utility. Saves about $499 versus outsourcing it, at the cost of a just a little time.
2. For plotting vector data like shapefiles on Google Maps, you can use the free utility Google Map Creator. Need to convert AutoCAD files to shapefile format? There’s a free plugin for MapWindow that lets you do that. Saves you $349 over outsourcing it.
3. Finally, for putting GIS Data into Google Earth format, there are a number of free or cheap options that let you do that. And to convert PDF files into a Google Earth format, use the process outlined above to convert a PDF to an image, and then georeference it. If you need to convert the image from UTM or some other coordinate system to Google Earth’s native coordinate system of latitude/longitude, you can use a free utility like GDALWarp (also to be covered in the future on this blog). You can then use a cheap ($20) utility like Valery Hronusov’s SuperOverlay to convert that image, or any georeferenced image, to a tiled Google Earth format. $20-50 in software costs, at most, versus an outsourced cost of $199-499.
BTW, if you have the need for any of these services, and don’t feel comfortable doing them yourself, email me with your requirements, and I’ll quote you a price that’ll be far less than those listed above ;-).
Another Geographic Data Service : GeoGarage, aimed at organizations that would otherwise not have the budget or the skills to publish geospatial content
Dear Leszek
A common problem for creating maps (thematic maps) on “free” of charge basis is to get the data to plot. There are some sites which offer free data, but sometimes you even have to pay for this data.
In the US you seem to have tons of good public data from various agencies including demographic data.
Outside the US, especially in developing countries e.g. in Africa it is much harder to get free data and detailed base maps e.g. administrative boundaries to third level. There is no real portal or what so ever I have found very useful and searches are sometime very cumbersome.
What is the purpose of this comment? Well a desperate search for decent “free” data aggregators for developing countries.
But maybe I have overseen some of your great tips.
Cheers
Askan.
Dear Leszek
Well my comment above is still valid, but I found something nice concerning African free GIS data:
http://www.maplibrary.org/stacks/Africa_lite.asp
Cheers
Askan.
Hi Askan,
Yes, getting good data outside the US and Canada can be problematical. I’ve posted some sources of international GIS data, which looking through the posts under the “data” label will reveal. Many of these are pretty random in nature – some will have exactly what you need, while others won’t. And even if the portal has the data, finding it can be a real challenge.
I’m planning a series of posts in the future on “making your own topo maps” that will cover some sources of international info, but I suspect you’re already familiar with most of them.
The “maplibrary.org” link you posted doesn’t seem to be working for me.
Dear Leszek
Before I posted the http://www.maplibrary.org/ link I checked it. It do not run very well, but acceptable. Today (Egypt time) it does not work. Sorry for that. It is/was a really good source.
Cheers
Askan.