def DataElement_from_raw(raw_data_element, encoding=None):
"""Return a DataElement from a RawDataElement"""
from pydicom.values import convert_value # XXX buried here to avoid circular import filereader->Dataset->convert_value->filereader (for SQ parsing)
raw = raw_data_element
# If user has hooked into conversion of raw values, call his/her routine
if config.data_element_callback:
raw = config.data_element_callback(
raw_data_element, **config.data_element_callback_kwargs)
VR = raw.VR
if VR is None: # Can be if was implicit VR
try:
VR = dictionaryVR(raw.tag)
except KeyError:
if raw.tag.is_private:
VR = 'OB' # just read the bytes, no way to know what they mean
elif raw.tag.element == 0: # group length tag implied in versions < 3.0
VR = 'UL'
else:
raise KeyError(
"Unknown DICOM tag {0:s} - can't look up VR".format(
str(raw.tag)))
try:
value = convert_value(VR, raw, encoding)
except NotImplementedError as e:
raise NotImplementedError("{0:s} in tag {1!r}".format(str(e), raw.tag))
return DataElement(raw.tag,
VR,
value,
raw.value_tell,
raw.length == 0xFFFFFFFF,
already_converted=True)
def DataElement_from_raw(raw_data_element, encoding=None):
"""Return a DataElement from a RawDataElement"""
from pydicom.values import convert_value # XXX buried here to avoid circular import filereader->Dataset->convert_value->filereader (for SQ parsing)
raw = raw_data_element
# If user has hooked into conversion of raw values, call his/her routine
if config.data_element_callback:
raw = config.data_element_callback(raw_data_element,
**config.data_element_callback_kwargs)
VR = raw.VR
if VR is None: # Can be if was implicit VR
try:
VR = dictionaryVR(raw.tag)
except KeyError:
if raw.tag.is_private:
VR = 'OB' # just read the bytes, no way to know what they mean
elif raw.tag.element == 0: # group length tag implied in versions < 3.0
VR = 'UL'
else:
raise KeyError("Unknown DICOM tag {0:s} - can't look up VR".format(str(raw.tag)))
try:
value = convert_value(VR, raw, encoding)
except NotImplementedError as e:
raise NotImplementedError("{0:s} in tag {1!r}".format(str(e), raw.tag))
return DataElement(raw.tag, VR, value, raw.value_tell,
raw.length == 0xFFFFFFFF, already_converted=True)
def DataElement_from_raw(raw_data_element: RawDataElement,
encoding: Optional[List[str]] = None) -> DataElement:
"""Return a :class:`DataElement` created from `raw_data_element`.
Parameters
----------
raw_data_element : RawDataElement
The raw data to convert to a :class:`DataElement`.
encoding : list of str, optional
The character encoding of the raw data.
Returns
-------
DataElement
Raises
------
KeyError
If `raw_data_element` belongs to an unknown non-private tag and
`config.enforce_valid_values` is set.
"""
# XXX buried here to avoid circular import
# filereader->Dataset->convert_value->filereader
# (for SQ parsing)
from pydicom.values import convert_value
raw = raw_data_element
# If user has hooked into conversion of raw values, call his/her routine
if config.data_element_callback:
raw = config.data_element_callback(
raw_data_element,
encoding=encoding,
**config.data_element_callback_kwargs)
VR = raw.VR
if VR is None: # Can be if was implicit VR
try:
VR = dictionary_VR(raw.tag)
except KeyError:
# just read the bytes, no way to know what they mean
if raw.tag.is_private:
# for VR for private tags see PS3.5, 6.2.2
if raw.tag.is_private_creator:
VR = 'LO'
else:
VR = 'UN'
# group length tag implied in versions < 3.0
elif raw.tag.element == 0:
VR = 'UL'
else:
msg = "Unknown DICOM tag {0:s}".format(str(raw.tag))
if config.enforce_valid_values:
msg += " can't look up VR"
raise KeyError(msg)
else:
VR = 'UN'
msg += " - setting VR to 'UN'"
warnings.warn(msg)
elif (VR == 'UN' and not raw.tag.is_private
and config.replace_un_with_known_vr):
# handle rare case of incorrectly set 'UN' in explicit encoding
# see also DataElement.__init__()
if (raw.length == 0xffffffff or raw.value is None
or len(raw.value) < 0xffff):
try:
VR = dictionary_VR(raw.tag)
except KeyError:
pass
try:
value = convert_value(VR, raw, encoding)
except NotImplementedError as e:
raise NotImplementedError("{0:s} in tag {1!r}".format(str(e), raw.tag))
if raw.tag in _LUT_DESCRIPTOR_TAGS and value:
# We only fix the first value as the third value is 8 or 16
try:
if value[0] < 0:
value[0] += 65536
except TypeError:
pass
return DataElement(raw.tag,
VR,
value,
raw.value_tell,
raw.length == 0xFFFFFFFF,
already_converted=True)
def DataElement_from_raw(raw_data_element: RawDataElement,
encoding: Optional[Union[
str, MutableSequence[str]]] = None,
dataset: Optional["Dataset"] = None) -> DataElement:
"""Return a :class:`DataElement` created from `raw_data_element`.
Parameters
----------
raw_data_element : RawDataElement
The raw data to convert to a :class:`DataElement`.
encoding : str or list of str, optional
The character encoding of the raw data.
dataset : Dataset, optional
If given, used to resolve the VR for known private tags.
Returns
-------
DataElement
Raises
------
KeyError
If `raw_data_element` belongs to an unknown non-private tag and
:attr:`~pydicom.config.settings.reading_validation_mode` is set
to ``RAISE``.
"""
# XXX buried here to avoid circular import
# filereader->Dataset->convert_value->filereader
# (for SQ parsing)
from pydicom.values import convert_value
raw = raw_data_element
# If user has hooked into conversion of raw values, call his/her routine
if config.data_element_callback:
raw = config.data_element_callback(
raw_data_element,
encoding=encoding,
**config.data_element_callback_kwargs)
vr = raw.VR
if vr is None: # Can be if was implicit VR
try:
vr = dictionary_VR(raw.tag)
except KeyError:
# just read the bytes, no way to know what they mean
if raw.tag.is_private:
# for VR for private tags see PS3.5, 6.2.2
vr = _private_vr_for_tag(dataset, raw.tag)
# group length tag implied in versions < 3.0
elif raw.tag.element == 0:
vr = VR_.UL
else:
msg = f"Unknown DICOM tag {str(raw.tag)}"
if config.settings.reading_validation_mode == config.RAISE:
raise KeyError(msg + " can't look up VR")
vr = VR_.UN
warnings.warn(msg + " - setting VR to 'UN'")
elif vr == VR_.UN and config.replace_un_with_known_vr:
# handle rare case of incorrectly set 'UN' in explicit encoding
# see also DataElement.__init__()
if raw.tag.is_private:
vr = _private_vr_for_tag(dataset, raw.tag)
elif raw.value is None or len(raw.value) < 0xffff:
try:
vr = dictionary_VR(raw.tag)
except KeyError:
pass
try:
value = convert_value(vr, raw, encoding)
except NotImplementedError as e:
raise NotImplementedError(f"{str(e)} in tag {raw.tag!r}")
except BytesLengthException as e:
message = (
f"{e} This occurred while trying to parse {raw.tag} according "
f"to VR '{vr}'.")
if config.convert_wrong_length_to_UN:
warnings.warn(f"{message} Setting VR to 'UN'.")
vr = VR_.UN
value = raw.value
else:
raise BytesLengthException(
f"{message} To replace this error with a warning set "
"pydicom.config.convert_wrong_length_to_UN = True.")
if raw.tag in _LUT_DESCRIPTOR_TAGS and value:
# We only fix the first value as the third value is 8 or 16
try:
if value[0] < 0:
value[0] += 65536
except TypeError:
pass
return DataElement(
raw.tag,
vr,
value,
raw.value_tell,
raw.length == 0xFFFFFFFF,
already_converted=True,
)
