Pb displaying an analyze file in anatomist !

[grova]

Hello I have strange behaviors of anatomist when trying to display an analyze binary file stored in 2 bytes.

Originally it was a GIS binary file that I can display very well using anatomist, then I converted it in analyze format using :

AimsFileConvert -i myfile.ima -o myfile.img -f SPM

myfile.img seems OK using display under SPM ... (values between 0 and 1), whereas in anatomist, instead of having 1 binary brain , I have 4 small brains in the upper corner of the image, and the values are not between 0 and 1 anymore, but rather between 0 and 1e-41 !!!! .... Has anyone seen that before ? Any idea ?

Thanks in advance

Christophe

[riviere]

Hi Christophe,

My guess is that there is somewhere a confusion on the type of data in the image:
if they are 16 bit in GIS format, then it's short int, and valus are obviously not between 0 and 1 (or they are binary).
If they are actually between 0 and 1, then it's float data (even if in SPM format they are stored on 16 bit with a scaling factor).
If they are actually 16 bit data read as 32, you could get the kind of strange effect you have described.
But there is definitely a problem in the converter or the reader if you get such a result. I will check if I get the same as soon as I have a moment...
Are you using the latest version of the package (2.3.5) ? Which system are you using ? Can you provide us with an example of faulting data ?

Denis

[Yann Cointepas]

Il could also be a problem due to a wrong minf file. Image header is first build from image format and then the minf file is read and its content overrides the image header. So if you have an old minf file from another image (for example with a different volume_dimension field), you may have this kind of problem.