DICOM RDF: VR "OB or OW"

Hi Erich,

I have to come back to this issue of "OB or OW".

The VR OB is defined as follows in the DICOM standard:
"An octet-stream where the encoding of the contents is specified by the 
negotiated Transfer Syntax. OB is a VR that is insensitive to byte 
ordering (see Section 7.3). The octet-stream shall be padded with a 
single trailing NULL byte value (00H) when necessary to achieve even 
length."

And the VR OW is defined as follows:
"A stream of 16-bit words where the encoding of the contents is 
specified by the negotiated Transfer Syntax. OW is a VR that requires 
byte swapping within each word when changing byte ordering (see Section 
7.3)."
(https://dicom.nema.org/medical/dicom/current/output/html/part05.html#sect_6.2)

We can resolve the problem of the endianess of OW by strictly using 
little endian and the DICOM standard supports it: "All nonretired 
Transfer Syntaxes in DICOM require the use of Little Endian Byte 
Ordering." 
(https://dicom.nema.org/medical/dicom/current/output/html/part05.html#sect_7.3)

But if we use xsd:base64Binary, we still have the problem if a single 
value from the stream is a byte (8-Bit) for OB or 2 bytes (16-bit) for OW.

Would this prevent us from relying solely on xsd datatypes and DICOM 
standard/ontology for standard attributes?

Regards,

Detlef

-- 
Detlef Grittner, MSc ISM, M.A.
CTO

SOHARD Software GmbH
Würzburger Str. 197
90766 Fürth

Phone: +49 (0) 911 97341-54
Fax:   +49 (0) 911 97341-10
E-Mail: detlef.grittner@sohard.de

Geschäftsführer: Peter Feltens, Sebastian Schnitzenbaumer
Sitz der Gesellschaft: Fürth
Registergericht: Amtsgericht Fürth; HRB 11478

Received on Thursday, 11 July 2024 16:47:04 UTC