Monthly Archive: March 2013

Here in Slovakia and also in Czech republic our government uses special spatial geographic system called S-JTSK. This system uses x, y and z axis. However global standard is WSG84 (GPS position with latitude and longitude). Problem occurs while we want to convert this S-JTSK to WSG84. There are some programs which can do this but there are no good lightweight libraries which could be used and would be fast. So I analyzed one of these convertors in excel, extracted formulas and implemented it in Java. First thing we need to do is to convert S-JTSK x, y to S-JTSK…
Read more

While crawling our beloved web we usually want to bind objects to GPS coordinates so we know where they are. Czech republic is not like any other country. In Czech republic there is search engine more popular than google no kidding. This search engine is called Seznam. Seznam provides services like search engine, catalogues, maps and many others. Seznam maps use special coordinate system which uses x and y axis. We usually want to convert these to GPS position. It is possible with their API but who would call their API when you can easily convert these coordinates with simple…
Read more

Once upon a time we had a school project where we had to implement SIP stateful proxy. I took this serious and created rich document describing possible problems and solutions working with JainSIP for Java. Without further adduce I present you google doc containing questions and answers. Slovak Version I have also implemented SIP to XMPP gateway. If anyone is ever interested in this, feel free to contact me and I can provide you source code of my solution.