Thread: VOICES Traffic Data

Basically what I had to do was get a list of all the intersections that were available on www.sigalert.com and ran them through a seperate process and got their lat/long. I then just store these lat/long values and associate them with the intersections on the site. Therefore the lat/long values are static and all I do is update the speeds based on the intersections. This is not dynamic in the sense that if they add a new intersection to their traffic database I will have to figure out its lat/long and add it to the DB, but how often do they add exits. This was the best method I found so far.

how do you guys plan on pulling this down as realtime data? you need a full on internet connection or is a WAP phone with bluetooth possible?

I get on the internet in my car with my GSM cellphone via GPRS. Also there are tons of places I can get on the internet around town. In the city, in the US, all you have to find the nearest StarBucks and you can get on the Internet with wireless B or G and download the most recent content. There is actually a StartBucks right by my house at the light I have to sit at to get on the Interstate. I get high speed internet access for multiple minutes every morning and that would be a perfect time to download weather and traffic data.

I sent out an email to the US dept of transportation basically asking them where to find real-time data, since the process of doing google searches over and over again was getting to be a real pain. The links they pointed me to seem promising, although sometimes it can take a little digging to find what you are looking for:

The National Traffic and Road Closure Information web site available on the Federal
Highway Administration (FHWA) web site has an interactive map of the United States
which will direct you to travel and traffic information by state:
http://www.fhwa.dot.gov/trafficinfo/index.htm#NATL

The FHWA home page is:
http://www.fhwa.dot.gov

I finally got my traffic program up and working. Basically I created an XML structure that I use to gather info from. Here is an example.


<CA>
<SAN>
<ROAD RDURL="http://www.sigalert.com/speeds.asp?Region=San+Diego&amp;Road=5%20North">
<INTERSECTION>
<STREETNAME>Hawthorn St</STREETNAME>
<LAT>32.72712</LAT>
<LONG>-117.16722</LONG>
</INTERSECTION>
<INTERSECTION>
<STREETNAME>India St</STREETNAME>
<LAT>32.73199</LAT>
<LONG>-117.17146</LONG>
</INTERSECTION>
</ROAD>
</SAN>
</CA>


I then use the url in the road section to download the content and loop through the streetnames and scrape the current speed. I then add all the pushpins based on the lat/long in the xml and it looks awesome in mappoint. Basically I just did one Highway in Souther California right now. Getting the lat/longs is the only hard part. Mappoint is not accurate enough, because you have to be able to show the North and the South of one Interstate/Freeway. I marked all those exits with pushpins and then extracted the correct lat/longs just to make sure I could get it too work. I just installed MapMarker and I am going to attempt to build an application that will take intersections... streetname/highway and hopefully it will give me good lat/longs. Then with that program I can build all the XML files for all the regions and roads. Then you just have to have custom functions that do the parsing for each URL/Region. I have the parser written that will do all of CA. I also included some pictures of my Weather app. It gets the weather based on the current zipcode it gets from reverse geocoding lat/long from your GPS receiver.

Anyone used MapMarker for intersection geocoding?

Veetid I really like what you have set up, it looks really good. I do have some comments though. You might be treading on thin ice with The Weather Channel by using their maps. I am friends with someone who worked there for about 10 yrs and from what I hear there are some people there that....well...you dont want to deal with. Besides there are plenty of other sources of weather data that you can do whatever you want with. Heck you can even copy and paste anything and everything from a national weather service site, turn around and sell it for $200/view, and it is completely legal. I can recommend a bunch of other sites, which if memory serves me, should be fairly easy to extract imagery from as well a whole bunch of other info like weather watches and warnings. Let me know what ya think.

The only thing I get from the Weather Channel is the radar image. All the other data comes from a different source that is setup for people to scrape. I don't plan on selling this to anyone ever.... Basically I modeled the weather scrape totally based on MythWeather. MythWeather is a linux application that retrieves weather information inside of Myth (a linux PVR system). MythWeather has been out on the internet since 2003 and has a large audience. They have had no issues, due to the fact that it is open source and no revenue is generated from the image... (Legally, if I am not selling, they can't do anything except try to make it harder for me to scrape, which they attempt to do, unsuccesfully.... Do you know how many sites on the internet grab and use that image.... thousands and thousands.... I would love to see weather.com try to do something to all those sites....)

Anyway.... If you give me a good url that allows me to pass in a postalcode (that includes non-us) and displays a good looking radar image, then I got no problems checking it out..