Source code for pydicom.datadict

# Copyright 2008-2018 pydicom authors. See LICENSE file for details.
# -*- coding: utf-8 -*-
"""Access dicom dictionary information"""

from pydicom.config import logger
from pydicom.tag import Tag, BaseTag

# the actual dict of {tag: (VR, VM, name, is_retired, keyword), ...}
from pydicom._dicom_dict import DicomDictionary

# those with tags like "(50xx, 0005)"
from pydicom._dicom_dict import RepeatersDictionary
from pydicom._private_dict import private_dictionaries
import warnings

# Generate mask dict for checking repeating groups etc.
# Map a true bitwise mask to the DICOM mask with "x"'s in it.
masks = {}
for mask_x in RepeatersDictionary:
    # mask1 is XOR'd to see that all non-"x" bits
    # are identical (XOR result = 0 if bits same)
    # then AND those out with 0 bits at the "x"
    # ("we don't care") location using mask2
    mask1 = int(mask_x.replace("x", "0"), 16)
    mask2 = int("".join(["F0" [c == "x"] for c in mask_x]), 16)
    masks[mask_x] = (mask1, mask2)

def mask_match(tag):
    for mask_x, (mask1, mask2) in masks.items():
        if (tag ^ mask1) & mask2 == 0:
            return mask_x
    return None

[docs]def add_dict_entry(tag, VR, keyword, description, VM='1', is_retired=''): """Update pydicom's DICOM dictionary with a new entry. Notes ---- Dose not permanently update the dictionary, but only during run-time. Will replace an existing entry if the tag already exists in the dictionary. Parameters ---------- tag : int The tag number for the new dictionary entry VR : str DICOM value representation description : str The descriptive name used in printing the entry. Often the same as the keyword, but with spaces between words. VM : str, optional DICOM value multiplicity. If not specified, then '1' is used. is_retired : str, optional Usually leave as blank string (default). Set to 'Retired' if is a retired data element. See Also -------- pydicom.examples.add_dict_entry Example file which shows how to use this function add_dict_entries Update multiple values at once. Examples -------- >>> from pydicom import Dataset >>> add_dict_entry(0x10011001, "UL", "TestOne", "Test One") >>> add_dict_entry(0x10011002, "DS", "TestTwo", "Test Two", VM='3') >>> ds = Dataset() >>> ds.TestOne = 'test' >>> ds.TestTwo = ['1', '2', '3'] """ new_dict_val = (VR, VM, description, is_retired, keyword) add_dict_entries({tag: new_dict_val})
[docs]def add_dict_entries(new_entries_dict): """Update pydicom's DICOM dictionary with new entries. Parameters ---------- new_entries_dict : dict Dictionary of form: {tag: (VR, VM, description, is_retired, keyword),...} where parameters are as described in add_dict_entry See Also -------- add_dict_entry Simpler function to add a single entry to the dictionary. Examples -------- >>> from pydicom import Dataset >>> new_dict_items = { ... 0x10011001: ('UL', '1', "Test One", '', 'TestOne'), ... 0x10011002: ('DS', '3', "Test Two", '', 'TestTwo'), ... } >>> add_dict_entries(new_dict_items) >>> ds = Dataset() >>> ds.TestOne = 'test' >>> ds.TestTwo = ['1', '2', '3'] >>> add_dict_entry(0x10011001, "UL", "TestOne", "Test One") >>> ds = Dataset() >>> ds.TestOne = 'test' """ # Update the dictionary itself DicomDictionary.update(new_entries_dict) # Update the reverse mapping from name to tag new_names_dict = dict([(val[4], tag) for tag, val in new_entries_dict.items()]) keyword_dict.update(new_names_dict)
[docs]def get_entry(tag): """Return the tuple (VR, VM, name, is_retired, keyword) from the DICOM dictionary If the entry is not in the main dictionary, check the masked ones, e.g. repeating groups like 50xx, etc. """ # Note: tried the lookup with 'if tag in DicomDictionary' # and with DicomDictionary.get, instead of try/except # Try/except was fastest using timeit if tag is valid (usual case) # My test had 5.2 usec vs 8.2 for 'contains' test, vs 5.32 for dict.get if not isinstance(tag, BaseTag): tag = Tag(tag) try: return DicomDictionary[tag] except KeyError: if not tag.is_private: mask_x = mask_match(tag) if mask_x: return RepeatersDictionary[mask_x] raise KeyError("Tag {0} not found in DICOM dictionary".format(tag))
[docs]def dictionary_is_retired(tag): """Return True if the dicom retired status is 'Retired' for the given tag""" if 'retired' in get_entry(tag)[3].lower(): return True return False
[docs]def dictionary_VR(tag): """Return the dicom value representation for the given dicom tag.""" return get_entry(tag)[0]
[docs]def dictionary_VM(tag): """Return the dicom value multiplicity for the given dicom tag.""" return get_entry(tag)[1]
[docs]def dictionary_description(tag): """Return the descriptive text for the given dicom tag.""" return get_entry(tag)[2]
[docs]def dictionary_keyword(tag): """Return the official DICOM standard (since 2011) keyword for the tag""" return get_entry(tag)[4]
[docs]def dictionary_has_tag(tag): """Return True if the dicom dictionary has an entry for the given tag.""" return (tag in DicomDictionary)
[docs]def keyword_for_tag(tag): """Return the DICOM keyword for the given tag. Will return GroupLength for group length tags, and returns empty string ("") if the tag doesn't exist in the dictionary. """ try: return dictionary_keyword(tag) except KeyError: return ""
# Provide for the 'reverse' lookup. Given the keyword, what is the tag? logger.debug("Reversing DICOM dictionary so can look up tag from a keyword...") keyword_dict = dict([(dictionary_keyword(tag), tag) for tag in DicomDictionary])
[docs]def tag_for_keyword(keyword): """Return the dicom tag corresponding to keyword, or None if none exist.""" return keyword_dict.get(keyword)
[docs]def tag_for_name(name): """Deprecated -- use tag_for_keyword""" msg = "tag_for_name is deprecated. Use tag_for_keyword instead" warnings.warn(msg, DeprecationWarning) return tag_for_keyword(name)
[docs]def repeater_has_tag(tag): """Return True if the DICOM repeaters dictionary has an entry for `tag`.""" return (mask_match(tag) in RepeatersDictionary)
REPEATER_KEYWORDS = [val[4] for val in RepeatersDictionary.values()]
[docs]def repeater_has_keyword(keyword): """Return True if the DICOM repeaters element exists with `keyword`.""" return keyword in REPEATER_KEYWORDS
# PRIVATE DICTIONARY handling # functions in analogy with those of main DICOM dict
[docs]def get_private_entry(tag, private_creator): """Return the tuple (VR, VM, name, is_retired) from a private dictionary""" if not isinstance(tag, BaseTag): tag = Tag(tag) try: private_dict = private_dictionaries[private_creator] except KeyError: msg = "Private creator {0} ".format(private_creator) msg += "not in private dictionary" raise KeyError(msg) # private elements are usually agnostic for # "block" (see PS3.5-2008 7.8.1 p44) # Some elements in _private_dict are explicit; # most have "xx" for high-byte of element # Try exact key first, but then try with "xx" in block position try: dict_entry = private_dict[tag] except KeyError: # so here put in the "xx" in the block position for key to look up group_str = "%04x" % elem_str = "%04x" % tag.elem key = "%sxx%s" % (group_str, elem_str[-2:]) if key not in private_dict: key = "%sxxxx%s" % (group_str[:2], elem_str[-2:]) if key not in private_dict: msg = ("Tag {0} not in private dictionary " "for private creator {1}".format(key, private_creator)) raise KeyError(msg) dict_entry = private_dict[key] return dict_entry
[docs]def private_dictionary_VR(tag, private_creator): """Return the dicom value representation for the given dicom tag.""" return get_private_entry(tag, private_creator)[0]
[docs]def private_dictionary_VM(tag, private_creator): """Return the dicom value multiplicity for the given dicom tag.""" return get_private_entry(tag, private_creator)[1]
[docs]def private_dictionary_description(tag, private_creator): """Return the descriptive text for the given dicom tag.""" return get_private_entry(tag, private_creator)[2]