GeoTIFF gurus,

I am trying to figure out the best way to deal with the unfortunate "black
areas" that occur frequently in our downloaded satellite imagery. I set the
OutputTransparentColor to 000000 and it works fine for uncompressed or
losslessly compressed data just fine. However, when using JPEG-In-TIFF for
max compression/space savings, you get the dreaded black edge created by
JPEG compression.

I am using GDAL command line utilities.

With lossless compression like LZW, but only get about 2:1 compression.

I want to use JPEG-In-TIFF with YCBCR colorspace for 20:1 compression
goodness.

If I crank up the the JPEG_QUALITY to 100 it helps, but still pretty
noticeable.

I have tried using "-mask mask" options in gdal_translate when I convert
from the original format. But I'm not really sure what that does since the
documentation is thin. There seems to be no way to tell it to create a new
mask band using any source values of 0,0,0 as nodata.

I have put together a quick Word doc with visuals of 3 different options -
LZW, JPEG 100, and JPEG 80 showing files size and resulting layer preview
in GeoServer.

I have tried various tricks with RasterSymbolizer like trying to set
"nearblack" pixels to zero. But that will effect "good" data too, so not a
very good option.

Any suggestions on this would be greatly appreciated. Thanks!

Jason Newmoyer
Newmoyer Geospatial Solutions
843.606.0424
ja...@newmoyergeospatial.com
------------------------------------------------------------------------------
Find and fix application performance issues faster with Applications Manager
Applications Manager provides deep performance insights into multiple tiers of
your business applications. It resolves application problems quickly and
reduces your MTTR. Get your free trial!
https://ad.doubleclick.net/ddm/clk/302982198;130105516;z
_______________________________________________
Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users

Reply via email to