[Insight-users] ImageIOFactory problem

[Christoph Palm]

Hi there,

I work with gipl images and had troubles reading some
of them. After debugging it, it turns out to be a problem of the
ImageIOFactory, especially with the GDCM image reader. In fact, the
imageIOBase was by error assigned to GDCM instead of GIPL. Then, of
course, everything seriously went wrong and ended up with false buffer
allocations and a segmentation fault. The wrong assignmed happend,
because within the factory all possible reader are tested to be the
right one. The first one was rejected, because the filename was not
properly. Ok. The second one was the GDCM reader, where no filename
testing is applied. In gdcmDocument.cxx, function CanReadFile
the first Bytes are read in as Uint16 and tested to be some numbers.
If one of these numbers are found, a dicom image without preample is
assumed and the function returns true.

Unfortunately, by coincidence obviously my gipl images showed one of
these numbers, namely 1,  at the beginning of the file. In a gipl image
the header starts with UShort numbers for the dimensions. My dimensions
for the error case were 256 256 1 1 (since gipl images are always 4D).
If I change the dimensions to 255 256 1 1, for example, everything is
fine. Now my question: how to solve this in the Insight framework in a
clean way? I am not really familiar with DICOM varieties. Is it possible
to add a fileEnding test to the GDCM reader? 

By the way, I also found a bug in writing gipl images. This is already
putted into the BugTracker. Is it possible, that I am the one and only
here who is working with GIPL images? ;-)

Regards

Christoph