suever
commented
9 years ago From darcymason@gmail.com on September 18, 2010 09:06:21
This is strange. The two tags mention that are giving problems are private tags (group number is odd) which pydicom has always been able to ignore, since many would not be in the private dictionary anyway.
In pydicom's testfiles directory, I tried the following:
ds=dicom.read_file("CT_small.dcm") ds.AddNew((0x3F03,0x1001),"UN", "hi") ds.save_as("3f03") ds2=dicom.read_file("3f03") ds2 and it reads okay, and displays the new tag fine. Same for the (FFFF,FFFF) tag, but group FFFF is reserved by the DICOM standard (but not used as far as I can recall) so that is a strange one.
Maybe there is something different about your file. Is it implicit or explicit VR? Could you provide an anonymized example file for this?
Status: Accepted
From hans.j.j...@gmail.com on September 18, 2010 09:27:51
What steps will reproduce the problem? 1. For dicom files with tags that are not listed in the _dicom_dict.py file, the files can not be read, even if the dicom tags are not of any use to the application.
What I see instead is that the dicom.file_read() throws a KeyError stating that the key is not in the pre-defined dictionary, and the parts of the file that are extractable are not available for querying. What version of the product are you using? I tried both 0.9.4 and 0.9.5rc1. Please provide any additional information below. A hack that works for one of the data sets that was causing problems was to add the missing values to the dictionary. This is not very satisfying because I can not anticipate all the other instances of not reported tags that will encountered in the future. [johnsonhj@neuron mpy-svn-stats]$ tail -4 /Library/Python/2.6/site-packages/dicom/_dicom_dict.py '7Fxx0040': ('OW', '1', "Variable Coefficients SDDN", 'Retired'), '3F031001': ('NONE', '1', "Unknown Item", ''), 'FFFFFFFF': ('NONE', '1', "Unknown Item", ''), }
Proposal:
In dicom/datadict.py
replace: 41 def get_entry(tag): 42 """Return the tuple (VR, VM, name, is_retired) from the DICOM dictionary 43 ···· 44 If the entry is not in the main dictionary, check the masked ones, 45 e.g. repeating groups like 50xx, etc. 46 """ 47 tag = Tag(tag) 48 try: 49 return DicomDictionary[tag] 50 except KeyError: 51 mask_x = mask_match(tag) 52 if mask_x: 53 return RepeatersDictionary[mask_x] 54 else: 55 raise KeyError, "Tag %s not found in DICOM dictionary" % Tag(tag) 56
============= with ======================================= 41 def get_entry(tag): 42 """Return the tuple (VR, VM, name, is_retired) from the DICOM dictionary 43 ···· 44 If the entry is not in the main dictionary, check the masked ones, 45 e.g. repeating groups like 50xx, etc. 46 """ 47 tag = Tag(tag) 48 try: 49 return DicomDictionary[tag] 50 except KeyError: 51 mask_x = mask_match(tag) 52 if mask_x: 53 return RepeatersDictionary[mask_x] 54 else: 55 return ('NONE', '1', "Unknown Item : "+str(tag), '') 56
Original issue: http://code.google.com/p/pydicom/issues/detail?id=91