Greetings GDAL Community, I am developing an application [0] to process georeferenced raster hyperspectral imagery in ENVI format from NASA's Airborne Visual/Infrared Imaging Spectrometer (AVIRIS) [1].
The `map info` section of the header files contain an undocumented [2] rotation field which is currently ignored by GDAL. As a result, the image is rotated incorrectly when I process it with `gdalwarp` or the GDAL Python API. Furthermore, the image is scaled incorrectly when I try to override the geotransform. I documented my experiences on the GIS Stack Exchange [3]. It has previously been described on the GDAL mailing list [4] and bug tracker [5]. I believe this issue also affects ASTER imagery [6][7]. I have implemented a fix based off of branch `tags/2.1.3` and shared my code on GitHub [8]. It reads the `units` and `rotation` parameter from the `map info` section and uses these to calculate the geotransform. The scaling was off because the code expected the `units` parameter to be the last element in the list, when in my case it was the second to last. You can verify this behavior with the single-band image I have been using for testing [9]. You are welcome to evaluate my code and contribute it back to the library. I am a novice at both GDAL and GIS, so there may well be problems. I would be willing to submit a pull request against your GitHub mirror if desired. Peace, Taylor Alexander Brown [0] https://github.com/capstone-coal/pycoal [1] https://aviris.jpl.nasa.gov/ [2] http://www.harrisgeospatial.com/docs/enviheaderfiles.html [3] http://gis.stackexchange.com/questions/229952/rotate-envi-hyperspectral-imagery-with-gdal [4] https://lists.osgeo.org/pipermail/gdal-dev/2013-January/035146.html [5] https://trac.osgeo.org/gdal/ticket/1778 [6] http://yceo.yale.edu/opening-aster-files-envi [7] http://yceo.yale.edu/faq-page#t2n504 [8] https://github.com/OSGeo/gdal/compare/tags/2.1.3...browtayl:fix-envi-rotation?expand=1 [9] https://drive.google.com/open?id=0BxysdOuBmaIGalY5dVhCa1Y5M0k _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/gdal-dev
