Worked for me using the following: #Change black to white gdalbuildvrt -srcnodata 0 -vrtnodata 255 to-be-decollared.vrt to-be-decollared.tif #Run nearblack -white nearblack -white -o decollared.tif to-be-decollared.vrt
Luke -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Matt Wilkie Sent: Thursday, 28 April 2011 1:57 AM To: gdal-dev Subject: [gdal-dev] nearblack troubles Hi All, The geotiff here (http://www.maphew.com/Itches/Decollaring_with_nearblack) has two collars to be removed. The outermost consists of pure black (0,0,0) while the innermost is off-white (ranges from 240 thru 255). I used gdalsetnull[1] to change 0,0,0 to nodata, then ran `nearblack -white` on the result. I detect no difference in the output image even with a very large fuzz factor (-near 50) . What am I doing wrong? {{{ d:\>cmd /version Microsoft Windows [Version 6.1.7600] Copyright (c) 2009 Microsoft Corporation. All rights reserved. d:\>gdalinfo --version GDAL 1.8.0, released 2011/01/12 d:\>gdalinfo to-be-decollared.tif ...snip.... Band 1 Block=375x7 Type=Byte, ColorInterp=Red Band 2 Block=375x7 Type=Byte, ColorInterp=Green Band 3 Block=375x7 Type=Byte, ColorInterp=Blue d:\>copy to-be-decollared.tif 0-is-nodata.tif d:\>gdalsetnull 0-is-nodata.tif Initial nodata for band 1 None Output nodata for band 1 0.0 Initial nodata for band 2 0.0 Output nodata for band 2 0.0 Initial nodata for band 3 0.0 Output nodata for band 3 0.0 d:\>gdalinfo 0-is-nodata.tif ...snip.... Band 1 Block=375x7 Type=Byte, ColorInterp=Red NoData Value=0 Band 2 Block=375x7 Type=Byte, ColorInterp=Green NoData Value=0 Band 3 Block=375x7 Type=Byte, ColorInterp=Blue NoData Value=0 d:\>nearblack -white -near 50 -o no-collar-white.tif 0-is-nodata.tif d:\>gdalinfo no-collar-white.tif ...snip... Band 1 Block=64x64 Type=Byte, ColorInterp=Undefined Description = Layer_1 Metadata: LAYER_TYPE=athematic Band 2 Block=64x64 Type=Byte, ColorInterp=Undefined Description = Layer_2 Metadata: LAYER_TYPE=athematic Band 3 Block=64x64 Type=Byte, ColorInterp=Undefined Description = Layer_3 Metadata: LAYER_TYPE=athematic }}} [1] http://code.google.com/p/maphew/source/browse/trunk/gis/o4w_extras/bin/g dalsetnull.py thanks in advance for your time and thoughts, -- matt wilkie -------------------------------------------- Geomatics Analyst Information Management and Technology Yukon Department of Environment 10 Burns Road * Whitehorse, Yukon * Y1A 4Y9 867-667-8133 Tel * 867-393-7003 Fax http://environmentyukon.gov.yk.ca/geomatics/ -------------------------------------------- _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev If you have received this transmission in error please notify us immediately by return e-mail and delete all copies. If this e-mail or any attachments have been sent to you in error, that error does not constitute waiver of any confidentiality, privilege or copyright in respect of information in the e-mail or attachments. Please consider the environment before printing this email. _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
