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How Satnav Maps Are Made
Barence writes "PC Pro has a feature revealing how the world's biggest satnav firms create their maps. Nokia's Navteq, for example, has a huge database of almost 24 million miles of road across the globe. For each mile of road there are multiple data points, and for each of those positions, more than 280 road attributes. The maps are generated from public data and driver feedback, not to mention its own fleet of cars with 360-degree cameras on the top. There's an IMU (inertial measurement unit) for monitoring the pitch of the road, and the very latest in 3D surface-scanning technology too. This light detection and ranging (LIDAR) detector captures 1.3 million three-dimensional data points every second, mapping the world around Navteq's field vehicles in true 3D. The feature also investigates whether commercial mapping firms will be replaced by open-source maps." That last line makes me think of the difference between conventionally published encyclopedias and Wikipedia; "replaced by" is an odd standard in a big marketplace of ideas.
...let me just warm up my 360 degree camera and my LIDAR gear, like we all have one, and go take mapping data for my neighbourhood...
Operation Guillotine is in effect.
Way back I worked at a DOT they were buying the sat maps from the Russians very good positional accuracy but no data to go with them. We would take the census maps that are useless for positions but have all the road names house numbers etc. The feds had sat maps as well but refused to sell them of give them to the states. We also merged it with data from a fleet of vans primarily with a gps and camera's (going to laser disk no less). A whole crew of people would spend all day matching things by hand and merging the data.
No sir I dont like it.
What about updating old roads that get changed?
also when they build that new part of I-355 it took for ever to show up on the on line maps and even a radio station made fun of it.
It wasn't so long that tom-tom were criticizing openstreetmap, and trying to pretend their data was better than crowd-sourced data.
They have the WORST maps available. Most of it is wrong, very low detail in any town that is smaller than 300,000 people. And they charge anal rape prices for their map updates.
I had one of the first in car nav systems, the Clarion Auto PC and the navteq maps were borderline worthless. the maps were missing most roads, no data about most one way streets, etc..
In fact 10 years later in 2009 I had the unfortunate experience of using Navteq data in a Jeep Grand Cherokee Nav system and once again crap maps, and it even had roads in locations that have not existed for decades, so their data set is still out of whack so bad it's not funny.
No thanks. I avoid all products that say "Navteq map database" on them.
Garmin uses Navteq but then uses teleatlas to correct the mess that is Navteq. Their maps are a hybrid of 4 different map database sources ran through their servers to correct them. So far I have had OK luck with Garmin's source database. I stopped using Megallan as they switched to the Navteq low quality database.
Want good maps in your GPS? teleatlas as the data source.
Do not look at laser with remaining good eye.
>If it's only around the vehicle it's not 'true' 3D.
I think they mean 3D as in the car can go up a hill and the change in altitude is also recorded.
I want a list of atrocities done in your name - Recoil
The article implies that the only ability to modify the data on Google Maps is using the Report a Problem link, but many countries in the world, including the US and Canada, allow everything to be edited directly by anyone using Map Maker. Edits are reviewed by both a team of over 500 trusted users worldwide and by Google employees. As trust is built up by making good edits and reviewing the edits of others, more things can be changed without requiring approvals. It's like an MMORPG for map geeks, except that it produces actual useful results in the real world. More info in the Getting Started Guide.
Natvteq has actually very good maps, particularly in Europe. The reason why your map looks bad is most likely due to your particular gear vendor. Garmin, Becker, Blaupunkt, Falk, etc. they buy maps from Navteq or Teleatlas, and they compile it for whatever their main goal and budget. In order to reduce the map size and save money, they compress the data using a battery of techniques. One common technique is decimation, where they simply remove geometry points to save space, leaving mostly the ones that represent intersections and a few in the middle. POI suffer as well.
So please don't be too fast in blaming a map vendor, where the fault is almost certainly from your navigation system vendor.