[OSM-legal-talk] ODbL and publishing source data

Eugene Alvin Villar seav80 at gmail.com
Tue Nov 29 14:10:43 GMT 2011

On Tue, Nov 29, 2011 at 6:42 PM, Ed Avis <eda at waniasset.com> wrote:
>>The European definition of a database is "a collection of independent
>>works, data or other materials arranged in a systematic or methodical
>>way and individually accessible by electronic or other means".
>>Individual pixels comprising a typical image (say a PNG map tile) are
>>not independent works. Each pixel cannot stand on its own and aren't
>>useful unless considered together with its neighboring pixels to form
>>an image.
> That makes some sense but you are implicitly taking the individual pixel as
> the level of granularity.  If you took the OSM planet file as your example
> once again, you could state that neither the individual co-ordinate numbers like
> 50.1234, nor individual tag strings like 'highway', have any independent
> existence.  They must stand together with other data items to form a complete
> object such as a node, which even then may not have much meaning without others.

The difference is that for the OSM database, you can construct a
systematic level of granularity where individual objects at that
granularity are individually useful. Certainly, individual tags or
individual pairs of coordinates are not generally useful but a
collection of tagged POIs, ways, and relations are each individually

Whereas for a *typical* image consisting of a matrix of pixels,
there's no level of granularity that would make individual objects
generally useful, whether those objects are single pixels, or rows of
pixels, or columns of pixels, or tiles of 8x8 pixels. You have to take
the image as a whole to make sense of it.

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