2015.04.03 01:59 "Re: [Tiff] problem reading directories past 2GB on a 64bits system", by Bob Friesenhahn
I'm using libtiff 4.0-3 on Ubuntu (64bits) 14.04.
I'm trying to read tiff files that are signed 16bits. Everything run smoothly for files smaller than 2Gb. But I cannot access directories past that limit.
TIFFSetDirectory returns the following error in those cases:
TIFFFetchDirectory: Sanity check on directory count failed, zero tag
directories not supported.
Failed to read directory at offset 256. TIFFReadDirectory:
Opening as bigtiff doesn't make a difference (expected since it's still less than 4Gb).
> Any ideas of what might be going on ?
Now that I am looking at the code, I see that the directory count is expected to fit in a 16-bit storage size. Is it possible that you have more than 64k entries?
This is the relevant code (after passing several other checks):
dircount16 = (uint16)dircount64;
dirsize = 20;
if (dircount16 == 0 )
"Sanity check on directory count failed, zero tag directories not supported");
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/