Hi all,
I have a problem with Jpeg compressed Tiff images ang GDAL 1.7 since
revision 17563
The Geotiff driver can no longer read some of these images.
These images have all the same characteristics :
- GeoTiff Image
- Jpeg Compression
- RGB BitsPerSample 8
- Photometric=YCbCr
- Not Tiled
- Width > 2000 and Height > 2000
- Image OK in any standard Viewer
- No problem with GDAL 1.6.2
A simple command like :
gdal_translate imgpb17.tif img.png -of PNG does not work.
( Windows XP 32b and Linux 64b )
--> There's a lot of warnings :
....
Warning 1: imgpb17.tif:fractional scanline not read
...10...20.Warning 1: imgpb17.tif:fractional scanline not read
Warning 1: imgpb17.tif:fractional scanline not read
...
Warning 1: imgpb17.tif:fractional scanline not read
More than 1000 errors or warnings have been reported. No more will be
reported f
rom now.
..30...40...50...60...70...80...90...100 - done.
and the output image is "black"
As a workaround, I modified the following line in frmts/gtiff/geotiff.cpp
line 4840
if( !TIFFIsTiled(hTIFF)
&& nBitsPerSample == 8
&& nBlockYSize == nYSize
&& nYSize > 2000
&& !bTreatAsRGBA )
{
/* bTreatAsSplit = TRUE; */ <---------
}
But it's only a workaround, not a solution
Here is a test image : http://www.meteo.fr/special/gdal/imgpb17.tif
Could you confirm that this is really a bug and not a mistake on my part.
Best regards
Régis Visière
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