[OAM-talk] a dramatically simplified technical proposal

[Steven M. Ottens]

Brian Russo wrote:
> If I'm not mistaken the 256^2 PNG restriction is because that is what 
> the WMS-C standard specifies (A flaw in the standard IMO - most of our 
> tiles are JPG).
The WMS-C standard doesn't specify the tilesize nor the format. The Web 
spherical mercator however does specify a tilesize (256x256) so that 
explains the 256x256 in the proposal. I do agree that it makes more 
sense to use JPEG in stead of PNG for imagery tiles however.
> (Totally not trying to derail this main discussion)
(I'm derailing it even more)
> Overall I think your revised standard looks great though I admit I 
> haven't pored over it in detail.
>
> I did have one question about licensing.
>
> "Each layer should be marked with the license of its source, including 
> (at a minimum) descriptive text for the license, plus flags for public 
> domain, attribution, non-commercial, and sharealike licensing. "
>
> I'm skeptical on the real utility of OAM if these sort of restrictions 
> are put in place. My preference would be for including only public 
> domain imagery. Anything else and I think we may just end up with a 
> collage of differently licensed imagery and you have to jump through 
> hoops to figure out what imagery is licensed under what etc.. Not to 
> be dramatic, but I'd say it diminishes my interest in OAM as a large 
> part of my interest is rooted in the problem that right now 
> releasability/licensing issues is really the main draw for me.  I.e. 
> we can use the basemap and/or release products knowing that other 
> people can use the basemap for "whatever".
You need to attach the license of the source data somehow to the layer. 
Otherwise you end up in a legal swamp.
The other point you are raising; is OAM worthwhile (for a certain user) 
if it contains non PD restrictions is a tough one. I'm not sure if CC-SA 
is a good license: ' If you alter, transform, or build upon this work, 
you may distribute the resulting work only under the same, similar or a 
compatible license.' This seems to mean that any map you create with OAM 
as a baselayer is suddenly CC-SA*). We have to create use cases for the 
different license to make clear how one can use a layer. (like 
http://wiki.openstreetmap.org/wiki/Open_Data_License/Use_Cases). Also we 
need to think long and hard for the best license for our 'own' data 
(since we cannot change the license from someone else's data). This 
however is a completely different discussion and the technical proposal 
does give us the freedom to do this in a different track, since it 
allows for tracking the licenses of the data. In the end we still can 
create a baselayer later on with only PD data so it can be used for 
'whatever'.

Regards,
Steven

*) IANAL