[talk-au] Improved AGRI Imagery Online
openstreetmap at firefishy.com
Sun Aug 5 18:04:05 BST 2012
I have updated the http://agri.openstreetmap.org/ imagery. JOSM and
Potlatch2 both imagery presets.
1) Fixed the black strip/blob issue at the overlap regions.
2) Improved the projection accuracy. (epsg:32749 to 32756)
3) Speed improvement. (Fixed double projection bug and needless resampling)
The imagery took 2 weeks to process after a number of false starts.
AGRI technical report + Legal + Control point photos are available here:
Example control photo:
I would appreciate help converting the ArcGIS database to a shapefile
(download all files here:
I believe the DB was created with ArcGIS 9.x. Seems gdal/ogr is only
able to handle v10 databases.
The compressed (lossless) imagery files and MapServer file are
available for download here: rsync://faffy.osm.org/agri_imagery/
The *.tif.ovr are lossy overview files can be rebuilt locally by using
the gdaladdo command below. Please be restrained in downloading the
files, 1.2TB will take a long time. I'd appreciate a heads-up email
prior to anyone downloading the imagery.
1) I reprocessed all the imagery from the source 2.8TB of ENVI rasters
to 1.2TB of GeoTIFF (BigTIFF, lossless DEFLATE z9):
2) Built gdaladdo JPEG overviews.
gdal commands used:
gdal_translate -of GTiff -co COMPRESS=DEFLATE -co PREDICTOR=2 -co
ZLEVEL=9 -co TILED=YES -co BLOCKXSIZE=512 -co BLOCKYSIZE=512 -co
TFW=YES -co BIGTIFF=YES -a_srs epsg:32755 PRISM_UTM55 PRISM_UTM55.tif
gdaladdo -ro --config COMPRESS_OVERVIEW JPEG --config
JPEG_QUALITY_OVERVIEW 75 --config INTERLEAVE_OVERVIEW PIXEL --config
PHOTOMETRIC YCBCR --config BIGTIFF_OVERVIEW YES --config
GDAL_TIFF_OVR_BLOCKSIZE 512 -r gauss PRISM_UTM55.tif 2 4 8 16 32 64
128 256 512 1024 2048 4096 8192
The server should be upgraded in the next 2 weeks. I currently do not
have any future plans on reprocessing the imagery further. Others may
wish to look at how to selectively choose the best imagery where there
is a region overlap to reduce the cloud cover.
Any questions? Happy to assist others in getting imagery online.
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