Hi Ed,
Yes, I'm aware of this problem. That's one of the reasons why I want to
go for a user survey, because I can't choose what is preferable between
"sharp" and "smooth". My intuitions tells me that it depends on the map
type and aims. I hope the survey results will allow the definition of
guidelines about this.
Cheers
Gilles
Ed McNierney wrote:
Gilles -
Just keep in mind that subjective metrics are, after all, subjective, and some of your metrics are mutually
exclusive. "Smoothness of lines" is normally accomplished by antialiasing those lines, making the
edges intermediate colors and a little "soft". This is a good thing, but is incompatible with
"sharpness of details", which is best accomplished without antialiasing but with more jagged
artifacts on curves and diagonal lines.
- Ed
Ed McNierney
Chief Mapmaker
Demand Media / TopoZone.com
73 Princeton Street, Suite 305
North Chelmsford, MA 01863
Phone: 978-251-4242, Fax: 978-251-1396
[EMAIL PROTECTED]
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gilles Bassière
Sent: Wednesday, October 10, 2007 8:38 AM
To: OSGeo Discussions
Subject: Re: [OSGeo-Discuss] How to assess rendering quality?
Hi Michael,
I'm more concerned with subjective metrics, I actually plan to survey
some users. The questionnaire will include some map samples and gather
user preference for each criteria. My problem is to identify what
questions/criteria should I ask to a user.
Gilles
Michael P. Gerlek wrote:
Gilles-
Is your idea to measure the quality by having a human look at outputs
(subjective metrics) or automatically via some analysis routine (objective
metrics)?
-mpg
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Gilles Bassière
Sent: Wednesday, October 10, 2007 3:01 AM
To: [email protected]
Subject: [OSGeo-Discuss] How to assess rendering quality?
Hi list,
I'm doing a comparative study of OpenSource cartographic servers
(Mapserver, Geoserver and Mapnik). Beside raw performance and
features,
I'd like to assess the rendering quality, say how pretty
produced maps
are. Precisely, I'm interested in the quality of the drawing work, my
point is not about symbology, nor styling of maps.
I have some problems to find a set of objective criteria I could
benchmark my servers against. So far, I have already identified the
following:
- sharpness of details
- smoothness of lines
- uniformity of colors
I'm open to any comments. Do you think these criteria are consistent
regarding the purpose of my study? Does anyone have other criteria to
suggest?
Regards
--
Gilles Bassiere
MAKINA CORPUS
30 rue des Jeuneurs
FR-75011 PARIS
http://www.makina-corpus.com
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_______________________________________________
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http://lists.osgeo.org/mailman/listinfo/discuss
--
Gilles Bassiere
MAKINA CORPUS
30 rue des Jeuneurs
FR-75011 PARIS
http://www.makina-corpus.com
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