Thread: My Traffic Program Source Code

Hi Veetid

I've been tinkering with the app this evening. I made some mods to it, to make it more touchscreen friendly, larger font, slightly larger buttons, etc. Find the GPS port etc, Nothing much.

I can see how the weather data is being fetched down by reverse geo-encoding the lat/lon to postcode and submitting off to MSN, but I dont understand a couple of things. I dont have the GPS plugged into the machine with VS2003, so I hardcoded the NMEA data to my location; however, why does it ask me for the region for traffic data? I would assume it would pick the location im in? Also, I couldnt see where it actually gets the traffic data from? It appears that the ca.xml takes the location and can return the uri to fetch for data right?

Anyway, im tired and bleary eyed, so I'll go to bed and look again tomorrow.

I like it, by the way, its the most interesting thing to come up for a while.

Basically the URL that it uses to fetch each subsection is in the XML.. You basically will see a URL for each road, such as I5 North and all data comes from www.sigalert.com... The reason I made it ask you is because you can't be sure which data you would want to show... For example I live in North County San Diego... My postal code would show up as Carlsbad... I would have had to code something in the program to go through a huge lookup list of every single postal code in CA and then map them down to the handful of cities I can retrieve traffic data for... This would have worked and is still a possible good idea, but wouldn't always be correct... For example... I get up in the morning and it would have a Carlsbad postal code and I hit traffic data.. Well I am in San Diego County, so most likely my program would choose and show San Diego traffic, but what if I was driving to LA? I would want to see Orange County / LA County traffic data to my north... The reason I made it ask is because my GPRS data plan cost money and I never wanted it to make an assumption... If I was in LA and wanted to see San Diego traffic to the South and I hit traffic and didn't think about it, it would automatically download LA traffic data, which is a lot of kilobytes... Since every state will only have a handful of options I figured leaving it at the state level would be fine.... I actually planned on a bunch of things, but have been really busy at work.. Let me know when you get done, I would love to see the changes you make...

Originally Posted by veetid

I have heard of the RDS, but don't know too much about it...

RDS (Radio Data System) is a service provided by radio stations. In addition to conventional analog FM radio signals, the stations also transmit additional information in the form of encoded digital signals that can be analysed by the car radio.

The following RDS services are currently available.

AF (Alternate Frequency): The car radio automatically selects the frequency with the best reception for the current programme.

EON: In the event that a traffic announcement (TA) is transmitted on any station in the station network, the car radio will automatically switch to that station for the duration of the message if you are currently listening to a station that does not transmit traffic information.

Music/Speech (M/S): In future, a number of radio stations will differentiate between music and speech programmes. It is possible (with DSC) to select a separate setting (bass and treble cuts) for speech programmes.

PI code: With the help of the PI code, the car radio can identify the station you have tuned into.

PS (Program Service): makes it possible to display the radio station name.

PTY (Program Type): a function supported to an increasing extent by the radio stations that enables the car radio to select radio stations by their genre (i.e. news, rock, pop, sport, etc.).

RT (Radiotext): additional information transmitted by the radio station (i.e. the title of the programme, the name of the artist, the name of the song, commercials etc.).

Tom

Thanks TommieG

I was looking around for something that would have an antenna and USB/serial connectors, it would simply output some form of XML corresponding to traffic it found. Or, if our US radios would do this then maybe the out-of-band data could be fed to a serial/USB port... A pipe dream I presume.

VTD

why did you bother with weather? In San Diego its either 'Perfect' or 'Near Perfect'. I suppose you might want to know which one

I agree

RDS is awesome...I don't understand why U.S. is always so slow to pick up on new technologies...it seems like the sheer size of the giant is slowing it down..I go to Europe (Poland) every summer, and I get to see better technologies (phones, RDS, etc.) than here.

Great idea with this program, btw

I've switched from mappoint 2002 to 2004, and now everything is working. I'm really impressed.
The only sad part is that downloading entire traffic data by xml takes about 2M of data. Comparatively, downloading it as a picture only takes 100k, at: http://traffic.tann.net/maps/lar6traffic.jsp

That is true... Especially for LA... There are so many roads and directions and you have to grab the entire text based pages and parse all the information out... I actually have been linking to a picture for my traffic because of my GPRS plan.. Hopefully ATT will have an unlimited data plan soon, but right now they don't...