Copyright Easter Eggs
From OpenStreetMap
A Copyright Easter Egg in terms of mapping is something that is done in a rather individual way so that its original author and probably the rather closely looking individual, probably with knowledge of the real world location is able to identify it. These are up to some degree non existing, slightly or heavily distorted map structures. Further misspelled or specially spelled names can represent such an easter egg.
The supposed main purpose of such an abnormality is of course the strengthening of the author when going into copyright cases. Such a unique structure will help him much in proving that someone else did copy his works by finding his very own design appearing in the opponents works.
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Don't confuse with an Errata
There's a fine line between easter eggs and errata
- Google Maps / Tele Atlas has Patrick's Hill in Cork where Camden Quay should be.
- Google Maps / Tele Atlas has decided to give a street name from another street (Harbet Road) in a different town to a segment of the A1(M) motorway in Hatfield. The segment of the motorway in the other direction is down as Walthamstow Avenue (North Circular Road), which again is entirely wrong.
- Vertices trick / mark There used to be a trick for marking cartography using Morse code, spreaded across the vectors defining geometry of features some companies would place words along the edge of a feature represented by regular length segments representing dots and dashes, in fact nothing that can not be easily removed with the simplest generalization algorithm, but you had to know the marks were there.
See also a Catalog of Errors.
OSMs view of the Topic
Fake street features are fairly hard to find, and we really have no idea how many there are. Fake streets, purpose mis-spellings and phantom churches are all thought to exist. It’s why OpenStreetMap asks you not to reference maps when entering data, and it’s one reason why we need our own free and accurate geodata.
It seems that some OSMers deliberately add errors to the OSM data as well (see posting on legal-talk by User:80n), so OSM itself cannot be said to be free of easter eggs.
Printed Maps that Lye
A-Z Map of Bristol
To the right is a tiny scan from an A-Z map of central Bristol. Only if you go and wander around Canynge Square in Bristol you see some nice houses (in the photo below the map) where that Close should be.
Lye Close isn’t in the index either. Weird, huh? Well, not really. It’s an easter egg, a surprise street (sometimes known as a "trap street") inserted so that if you attempt to copy the map then the copyright holder can prove you copied it. Otherwise, why would you have the nonsense street in your map if you didn’t get it from them?
Examples from Tele Atlas (used in Google Maps)
- Moat Lane, Finchley, London N3. Tele Atlas (as used by Google Maps) has this road, which doesn't exist. Not according to the Royal Mail, not according to Bartholomew, not according to personal experience.
- Torrington Place, Finchley, London N3, allegedly at the end of Arcadia Avenue N3. Tele Atlas has this road, which doesn't exist in reality. Not according to Royal Mail, not according to Bartholomew, not according to personal experience.
- The Avenue, Finchley, London N3. Tele Atlas has this short street at entirely the wrong angle, taking it straight through a block of flats, about 60 metres from its location in reality.
- Warwick Road and Tudor Close - Sutton Coldfield shows up a good example of a Tele Atlas easter egg. Or could it be that they planned to build the extension to Warwick Road and the Tudor Close spur but never did, in which case the detail for the map could have come from the planning stage. I'm not so sure though as the extension to Warwick runs through the back gardens of existing homes. Anyway, these roads don't exist in real life. Here is what the housing estate looks like on OSM as created from my GPX track.Blackadder 12:17, 3 Feb 2006 (GMT)
- Clapham Junction to Clapham Common a Tele Atlas Easter Egg showed a road running diagonal from the main intersection of Clapham Junction to Clapham Common, through several streets, rows of houses, and a department store. This easter egg was removed from Google maps at some point towards the end of 2006. The roads are now mapped on OSM.
- Zeuthen in Germany shows "Adolph-Menzel-Ring", "Otto-Nagel-Allee", "Max-Liebermann-Straße" and "Otto-Dix-Ring", which are all nonexisting. These streets are inside of forest. This is easy to detect. 4 different street names for an area as large as two houses. Correctly mapped in OSM.
- Zeuthen in Germany shows this nice sandglass shapped street "Leipziger Platz". Actually this street are and also have ever been uncurved and with a footpath inbetween.
- Freiburg (Brsg.) in Germany does not have the curvy road or path running through i.e. a school building.
OS vs. AA
The company OS maps sued the AA for copying their very own works and spreading the results to individuals as well as to third party mappers. Some 26 maps from AA were proven to be a more or less copy or incorporating data from OS and there was a nearly 7 digit pound fee for that. Several hundreds of maps are still under dispute at courts and would mean some 20 Million pound value for compensation. Compared to that the AA has some annual cash flow of about 30 Million pound and was already in some heavy struggle at that time.
Road signs that lie
There are also cases where the street signs are incorrect, but the maps are correct. For instance, the B550 from Highgate in London to Whetstone (according to official sources at the Department for Transport, and according to OS, Bartholomew, Tele Atlas and Mapquest Maps). There are road signs at the Colney Hatch intersection on the A406 North Circular Road that shows it as the B550 in one direction and B505 in another.
Digital Maps
Another class of Easter Eggs is implemented by digital map providers who do not want their map data compendiums copied. The lower bits of the geographic coordinates are mangled in some systematic way so that it would not be obvious to a user of the map, but would be something that could be shown in a Copyright trial to show that the data had been copied.
For instance if all the coordinates had a remainder of 3 when divided by seven, or were displaced from their real coordinates by some small but real offset. So don't use digital map coordinates from proprietary sources even if you were to compare every intersection and shape point on the map!
