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OSM Logo This user submits data to OpenStreetMap under the name pnorman.

This user uses or has experience with a iPad and is willing to answer questions on it from OSM users.

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Subversion Logo Pnorman commits code to OpenStreetMap SVN under the name pnorman.
en This user is a native speaker of English.

No Wikifiddling.png Go Do Some Mapping.png
OpenStreetMap isn't a computer project, it's an outdoors activity.
Less of the bulk imports and wikifiddling please.
Go outside and map!

About me

Engineering student at UBC. I live in New West.

I commute along Marine or the 91A frequently.


User:pnorman/BC Tagging (finished)

User:pnorman/Import Guidelines

gdal resampling timings

Based on surrey tile 018_40cm from 2008 orthophotos. These tests were not conducted rigorously, other processes were operating at the time, however gdal2tiles does not take advantage of multiple CPUs so it is likely this did not matter. cubicspline and lanczos had files unzipping in the background while running, but cubicspline is worthlessly fuzzy and lanczos is the slowest anyways.

Tile sampled: 18/41560/172317

gdal2tiles -z 18 -r *method* --s_srs=EPSG:26910 018_40cm.tif 018_40cm


lanczos: 25:00

cubicspline : 7:00

cubic: 2:15

bilinear: 1:90

near: 1:15

average: 1:40




Resample Cubicspline.png





Quality (sharpness): near, cubic, average, bilinear, cubicspline,

Quality (distortion): cubicspline, average, bilinear, cubic, near

Conclusions: Cubicspline is worthless with how fuzzy it is. Cubic, Near, Average are all options.