Peter, Does ELGIS GDAL uses internal libtiff (4.0beta) or external libtiff (3.8 or 3.9) ? I guess it is external libtiff, and then it could explain the issues you have with overviews and JPEG compression. There have been fixes in libtiff 4 to better support that situation (multiple IFDs with compression). Altertantively, you could probably workaround that by generating external overviews (add -ro to the gdaladdo command line), but no guarantees. By the way, the --config COMPRESS_OVERVIEW JPEG --config INTERLEAVE_OVERVIEW PIXEL --config JPEG_QUALITY_OVERVIEW 90 options only apply to external overviews, not internal ones.
> I'm doing quite some experiments with GDAL and image compression these days > > I do have an issue with geotiff 1.3/gdal 1.8.1 on CentOS 6 with packages > from ELGIS. The story goes like this: > > I create tiffs with > > gdal_translate -of GTiff -co COMPRESS=JPEG -co JPEG_QUALITY=90 > -co "TILED=YES" -co "BLOCKXSIZE=512" -co "BLOCKYSIZE=512" <infile> > <outfile> > > and then add overviews with (I do have to add the overlays in distinct > steps, otherwise gdaladdo aborts with an error message). > > gdaladdo --config COMPRESS_OVERVIEW JPEG --config INTERLEAVE_OVERVIEW > PIXEL --config JPEG_QUALITY_OVERVIEW 90 -r average <outfile> 3 > gdaladdo --config COMPRESS_OVERVIEW JPEG --config INTERLEAVE_OVERVIEW > PIXEL --config JPEG_QUALITY_OVERVIEW 90 -r average <outfile> 9 > gdaladdo --config COMPRESS_OVERVIEW JPEG --config INTERLEAVE_OVERVIEW > PIXEL --config JPEG_QUALITY_OVERVIEW 90 -r average <outfile> 27 > gdaladdo --config COMPRESS_OVERVIEW JPEG --config INTERLEAVE_OVERVIEW > PIXEL --config JPEG_QUALITY_OVERVIEW 90 -r average <outfile> 81 > > (Trying with power-of-2-steps gives the same result. If I drop all > options from gdaladdo: same result). > > I'll create a WMS service with MapServer 5.6.7 and do get a big red > square in the image. The square is "fixed" to the geografical position, > e.g. if I move the extend the square moves too. The square is situated > in the corner of the tiff file. > It appears only at some scales. If I change it very slightly, the square > remqins, if I change for more then approx 1%, it disappears. > > I've put the two images at > > http://www.r3-gis.com/gdal_issues/tiff_with_jpegcompression_and_overviews.jpeg > and > http://www.r3-gis.com/gdal_issues/tiff_with_nocompression_and_overviews.jpeg > . > > The problem disappears if I do not run gdaladdo on the images or when I > do not use Jpeg compression: > > gdal_translate -of GTiff -co "TILED=YES" -co "BLOCKXSIZE=512" -co > "BLOCKYSIZE=512" <origfile> <targetfile> > > There are some hits for > http://www.google.com/search?client=ubuntu&channel=fs&q=mapserver+artefacts+in+raster+gdal&ie=utf-8&oe=utf-8, > but mostly related to older versions of GDAL and without resolution. > > > Thanks, > > Peter > > -- > > Peter Hopfgartner > R3 GIS Srl - GmbH > www.r3-gis.com > > > _______________________________________________ > gdal-dev mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/gdal-dev > _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
