GSPS creation???

[jim]

Hi,


I'm working on a kind of Viewer which can make operations on the DICOM image (e.g. rotations,...). At the present time, when I receive
DICOM files (CR, CT, PET, MR, ..), I extract pieces of information from it and convert image in proprietor format.


I would like to send my files in DICOM format to a server. So, have I had to recreate the same Instance UID with a Grayscale Softcopy
Presentation State (referenced this Instance) or may I send this Image (with a rotation) just with conversion jpeg->DICOM ???

An other question:
Is it possible to compare two DICOM images which reprensent the same instance but with operations on one of it (like rotation,...) and deduce a Grayscale Softcopy Presentation State?? (in order to send the original Instance with it GSPS).

Thx for your reply...

[Marco Eichelberg]

If an image has any modification (such as a rotation) being applied, it must not be stored with the same SOP Instance UID, that is one of the few rules where the DICOM standard is very strict. The modified image must have a new SOP Instance UID. You can use the source image sequence to "point" back to the original DICOM image (SOP Instance UID) from which the image was derived.
If two images have the same SOP Instance UID, then they have to be identical except for the encoding options that DICOM explicitly leaves open (such as lossless compression, transfer syntax, sequence and item encoding, group length).
I could imagine that it would be possible to compare two images and automatically "derive" a presentation state that describes the conversion of one image into the other if the conversion steps are simple enough to be captured this way. However, I'd not volunteer to write that code which would be awfully complex.