[ome-users] Display rendering problems with big images

[Peter Zentis]

Hi all,

We are experiencing problems with "big" 32bit floating point images on our Omero server.
When we import such images by default they just look uniformly gray, because by default the images are rendered with a lookup table ranging from -2147483648.000 to 2147483647.000 as can be seen in the preview pane. In the insight-client the Min/Max-button has no effect, in the web-client the Min/Max-button sets the values to a range from -32768 to 32767 (completely independent of the image histogram). Interestingly, in the acquisition pane one can find correct min- and max-values in the metadata table, which manually copied to the preview pane allow for a useful display of the image.
Originally we noted the problem with dm4-files from our 4K Gatan camera. However, we can reproduce the problem also with other images e.g. generated with this ImageJ script:

run("Lena (68K)");
run("32-bit");
saveAs("Tiff", "noProblem.tif");
selectWindow("noProblem.tif");
run("Scale...", "x=- y=- width=3617 height=3617 interpolation=Bilinear average create");
saveAs("Tiff", "bigProblem.tif");

We do not have the problem with an image of 3616x3616 pixels, but with every image which is 3617x3617 pixels and bigger.
Moreover, there occurs another problem (only in the insight-client, but not in the web-client), when the images have been converted to a 16bit integer format before, apparently connected to the image dimensions in the same way: Images of 3617x3617 pixels have the preview pane completely disabled. However, in the Full Viewer via the rendering controls the settings pane is available and works well.

Do you think there is any possibility to fix this behaviour by adjusting our configuration? For now just pushing the limit for everything to work to 4096x4096 images would already be sufficient :) 

Cheers,
Peter


-- 
Peter Zentis
CECAD Imaging Facility
CECAD Cluster of Excellence | University of Cologne
Joseph-Stelzmann-Str. 26 | 50931 Cologne | Germany

phone:(+)49-221-478-84028

email: Peter.Zentis at uni-koeln.de

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: OpenPGP digital signature
URL: <http://lists.openmicroscopy.org.uk/pipermail/ome-users/attachments/20170804/0065b323/attachment.asc>