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ssec / sift

A visualization application for satellite imagery
http://sift.ssec.wisc.edu/
GNU General Public License v3.0
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Make sure geotiff pixel locations are treated as pixel centers #153

Open djhoese opened 5 years ago

djhoese commented 5 years ago

In GitLab by @djhoese on Nov 9, 2016, 14:43

Jay Cable at GINA brought up a possible issue with Polar2Grid where a half pixel shift can be seen when viewing produced geotiffs in QGIS. My guess is that QGIS isn't properly respecting the "pixel is an area" nature of most geotiffs. We should make sure I'm not doing the same in SIFT.

djhoese commented 5 years ago

In GitLab by @djhoese on Nov 9, 2016, 14:43

Polar2Grid issue: https://github.com/davidh-ssec/polar2grid/issues/121

djhoese commented 5 years ago

In GitLab by @djhoese on Nov 9, 2016, 15:39

FYI the solution was fixing the geotransform in the geotiff. The geotiff specification defines a PixelIsArea-style geotiff as having coordinates for the upper-left corner of the pixel. I was using the center of the pixel as is normal for scientific imagery data. I still need to verify how SIFT is doing it, but will like wait until after we move away from geotiffs as the default since all geotiffs will need to be regenerated.

djhoese commented 5 years ago

In GitLab by @djhoese on Oct 18, 2017, 21:19

changed time estimate to 15m