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tilezen / joerd

Joerd can be used to download, merge and generate tiles from digital elevation data
MIT License
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[docs] Slightly confusing description of GeoTIFF tiles #97

Open migurski opened 8 years ago

migurski commented 8 years ago

I think this description might be a bit confusing:

GeoTIFF format tiles are raw elevation data suitable for analytical use and are optimized to reduce transfer costs in 512x512 tile sizes but with internal 256x256 image pyramiding, in Mercator projection (EPSG:3857). … Allow for the larger tile size by referring to the tile coordinate of {z-1} parent tile.

If I understand correctly, the tiles can simply be thought of as double-resolution, 512x512 retina tiles? Mentioning image pyramids and zoom reduction feels like overmuch information.

kkowalsky commented 7 years ago

will clarify this!

nvkelso commented 7 years ago

Knowing about Image pyramiding was requested by an early tester of the service, more useful for desktop gdal uses.

On Nov 4, 2016, at 15:04, Katie Kowalsky notifications@github.com wrote:

will clarify this!

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migurski commented 7 years ago

Maybe we can tell just them? The part that’s actually confusing is the bit about referring to the parent’s tile coordinate; it sounds like you need to do something special to work around the tile size, when really you don’t need to do anything special. I would suggest about this amount of description:

GeoTIFF format tiles are raw elevation data suitable for analytical use. They are offered as standard web Mercator tiles at 512x512 pixel tile sizes, with elevation in meters.

nvkelso commented 7 years ago

Sure.

On Nov 5, 2016, at 00:17, migurski notifications@github.com wrote:

Maybe we can tell just them? The part that’s actually confusing is the bit about referring to the parent’s tile coordinate; it sounds like you need to do something special to work around the tile size, when really you don’t need to do anything special. I would suggest about this amount of description:

GeoTIFF format tiles are raw elevation data suitable for analytical use. They are offered as standard web Mercator tiles at 512x512 pixel tile sizes, with elevation in meters.

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