Hi,

I was looking for a way to generate a StudyInstanceUid when I found this function: ClearCanvas.Dicom.DicomUid.GenerateUid()

I took a look at the code and wondered why you don't use System.Guid.NewGuid()and simply add the result to your root?

I don't think that it is very likely that there will be chance that your GenerateUid function will generate one UID twice but  it should not be impossible.

Imagine a program that just generates one UID and exits. If this program is called several times in a second. It should be possible that the OS assigns the same process id in  a row. This can result in duplicated UIDs.

 Martin,

There is a limit of 64-characters on UIDs and character limitations where its not possible to just do an append.  You are right that there's a possibility of an OS assigning the same Process ID within a second causing issues within the UID generator.  We deemed the chance of this to be low enough that it wasn't worth coding around.

If you are interested in alternate UID generation techniques, there's a discussion about this on comp.protocols.dicom here:

groups.google.com/group/comp.protoc...1daff4bdaa

Also, the above thread references this document about generating a UID from a Guid:

www.dclunie.com/medical-image-faq/html/part2.html#UUID

Also, here's a reference from the OFFIS toolkit about their UID generation techniques:

forum.dcmtk.org/viewtopic.php

I hope this helps.

Steve