If a DICOM file does not define a Specific Character Set (0008,0005), what character set does it use by default? Is ASCII the default encoding for DICOM files?
TL;DR
A DICOM file contains German ä in one of the tags, but the file does not specify any character set. I assume that in this case the file is allowed to contain only ASCII symbols (the default character set) and report this file as invalid. Before I submit my change, I want to make sure that I understood DICOM correctly.
As specified in the Dicom Data Structures and Encoding
6.1.2.5.4 Levels of Implementation and Initial Designation
a) Attribute Specific Character Set (0008,0005) not present:
7-bit code Implementation level: ISO 2022 Level 1 - Elementary 7-bit code (code-level identifier 1)
Initial designation: ISO-IR 6 (ASCII) as G0. Code Extension shall not be used
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