private async Task <bool> ParseFragmentSequenceValueAsync(IByteSource source)
{
if (_parseStage == ParseStage.Value)
{
if (!source.Require(_length))
{
_result = DicomReaderResult.Suspended;
return(false);
}
var buffer = await source.GetBufferAsync(_length).ConfigureAwait(false);
buffer = EndianByteBuffer.Create(buffer, source.Endian, _fragmentItem == 1 ? 4 : _vr.UnitSize);
_observer.OnFragmentSequenceItem(source, buffer);
_parseStage = ParseStage.Tag;
}
return(true);
}
private async Task <bool> ParseValueAsync(IByteSource source)
{
if (_parseStage == ParseStage.Value)
{
// check dictionary for VR after reading length to handle 16-bit lengths
// check before reading value to handle SQ elements
var parsedVR = _vr;
// check dictionary for VR after reading length to handle 16-bit lengths
// check before reading value to handle SQ elements
if (_vr == DicomVR.Implicit || (_vr == DicomVR.UN && _isExplicitVR))
{
var entry = _dictionary[_tag];
if (entry != null)
{
_vr = entry.ValueRepresentations.FirstOrDefault();
}
if (_vr == null)
{
_vr = DicomVR.UN;
}
}
if (_tag == DicomTag.ItemDelimitationItem || _tag == DicomTag.SequenceDelimitationItem)
{
// end of sequence item
return(false);
}
while (_vr == DicomVR.SQ && _tag.IsPrivate && _length > 0)
{
if (!IsPrivateSequence(source))
{
_vr = DicomVR.UN;
break;
}
if (IsPrivateSequenceBad(source, _length, _isExplicitVR))
{
_badPrivateSequence = true;
// store the depth of the bad sequence, we only want to switch back once we've processed
// the entire sequence, regardless of any sub-sequences.
_badPrivateSequenceDepth = _sequenceDepth;
_isExplicitVR = !_isExplicitVR;
}
break;
}
var curIndex = source.Position;
// Fix to handle sequence items not associated with any sequence (#364)
if (_tag.Equals(DicomTag.Item))
{
source.Rewind();
_vr = DicomVR.SQ;
}
if (_vr == DicomVR.SQ)
{
// start of sequence
_observer.OnBeginSequence(source, _tag, _length);
_parseStage = ParseStage.Tag;
if (_length == 0)
{
_implicit = false;
source.PushMilestone((uint)(source.Position - curIndex));
}
else if (_length != _undefinedLength)
{
_implicit = false;
source.PushMilestone(_length);
}
else
{
_implicit = true;
}
var last = source.Position;
// Conformance with CP-246 (#177)
var needtoChangeEndian = false;
if (parsedVR == DicomVR.UN && !_tag.IsPrivate)
{
_implicit = true;
needtoChangeEndian = source.Endian == Endian.Big;
}
if (needtoChangeEndian)
{
source.Endian = Endian.Little;
}
await ParseItemSequenceAsync(source).ConfigureAwait(false);
if (needtoChangeEndian)
{
source.Endian = Endian.Big;
}
// Aeric Sylvan - https://github.com/rcd/fo-dicom/issues/62#issuecomment-46248073
// Fix reading of SQ with parsed VR of UN
if (source.Position > last || _length == 0)
{
return(true);
}
_parseStage = ParseStage.Value;
_vr = parsedVR;
}
if (_length == _undefinedLength)
{
_observer.OnBeginFragmentSequence(source, _tag, _vr);
_parseStage = ParseStage.Tag;
await ParseFragmentSequenceAsync(source).ConfigureAwait(false);
return(true);
}
if (!source.Require(_length))
{
_result = DicomReaderResult.Suspended;
return(false);
}
var buffer = await source.GetBufferAsync(_length).ConfigureAwait(false);
if (!_vr.IsString)
{
buffer = EndianByteBuffer.Create(buffer, source.Endian, _vr.UnitSize);
}
_observer.OnElement(source, _tag, _vr, buffer);
// parse private creator value and add to lookup table
// according to
// http://dicom.nema.org/medical/dicom/current/output/chtml/part05/sect_7.8.html
// Private Creator Data Elements numbered (gggg,0010-00FF) (gggg is odd)
// The VR of the private identification code shall be LO (Long String) and the VM shall be equal to 1.
if (_tag.IsPrivate && _tag.Element >= 0x0010 && _tag.Element <= 0x00ff)
{
var creator =
DicomEncoding.Default.GetString(buffer.Data, 0, buffer.Data.Length)
.TrimEnd((char)DicomVR.LO.PaddingValue);
var card = (uint)(_tag.Group << 16) + _tag.Element;
lock (_locker)
{
_private[card] = creator;
}
}
ResetState();
}
return(true);
}
private async Task<bool> ParseValueAsync(IByteSource source)
{
if (this.parseStage == ParseStage.Value)
{
// check dictionary for VR after reading length to handle 16-bit lengths
// check before reading value to handle SQ elements
var parsedVR = this._vr;
// check dictionary for VR after reading length to handle 16-bit lengths
// check before reading value to handle SQ elements
if (this._vr == DicomVR.Implicit || (this._vr == DicomVR.UN && this.isExplicitVR))
{
var entry = this.dictionary[this._tag];
if (entry != null)
{
this._vr = entry.ValueRepresentations.FirstOrDefault();
}
if (this._vr == null)
{
this._vr = DicomVR.UN;
}
}
if (this._tag == DicomTag.ItemDelimitationItem)
{
// end of sequence item
return false;
}
while (this._vr == DicomVR.SQ && this._tag.IsPrivate)
{
if (!IsPrivateSequence(source))
{
this._vr = DicomVR.UN;
break;
}
if (IsPrivateSequenceBad(source, this.isExplicitVR))
{
this.badPrivateSequence = true;
this.isExplicitVR = !this.isExplicitVR;
}
break;
}
if (this._vr == DicomVR.SQ)
{
// start of sequence
this.observer.OnBeginSequence(source, this._tag, this.length);
this.parseStage = ParseStage.Tag;
if (this.length != UndefinedLength)
{
this._implicit = false;
source.PushMilestone(this.length);
}
else
{
this._implicit = true;
}
var last = source.Position;
// Conformance with CP-246 (#177)
var needtoChangeEndian = false;
if (parsedVR == DicomVR.UN && !this._tag.IsPrivate)
{
this._implicit = true;
needtoChangeEndian = source.Endian == Endian.Big;
}
if (needtoChangeEndian)
{
source.Endian = Endian.Little;
}
await this.ParseItemSequenceAsync(source).ConfigureAwait(false);
if (needtoChangeEndian)
{
source.Endian = Endian.Big;
}
// Aeric Sylvan - https://github.com/rcd/fo-dicom/issues/62#issuecomment-46248073
// Fix reading of SQ with parsed VR of UN
if (source.Position > last || this.length == 0)
{
return true;
}
this.parseStage = ParseStage.Value;
this._vr = parsedVR;
}
if (this.length == UndefinedLength)
{
this.observer.OnBeginFragmentSequence(source, this._tag, this._vr);
this.parseStage = ParseStage.Tag;
await this.ParseFragmentSequenceAsync(source).ConfigureAwait(false);
return true;
}
if (!source.Require(this.length))
{
this.result = DicomReaderResult.Suspended;
return false;
}
var buffer = await source.GetBufferAsync(this.length).ConfigureAwait(false);
if (!this._vr.IsString)
{
buffer = EndianByteBuffer.Create(buffer, source.Endian, this._vr.UnitSize);
}
this.observer.OnElement(source, this._tag, this._vr, buffer);
// parse private creator value and add to lookup table
if (this._tag.IsPrivate && this._tag.Element != 0x0000 && this._tag.Element <= 0x00ff)
{
var creator =
DicomEncoding.Default.GetString(buffer.Data, 0, buffer.Data.Length)
.TrimEnd((char)DicomVR.LO.PaddingValue);
var card = (uint)(this._tag.Group << 16) + this._tag.Element;
lock (this.locker)
{
this._private[card] = creator;
}
}
this.ResetState();
}
return true;
}
private async Task<bool> ParseFragmentSequenceValueAsync(IByteSource source)
{
if (this.parseStage == ParseStage.Value)
{
if (!source.Require(this.length))
{
this.result = DicomReaderResult.Suspended;
return false;
}
var buffer = await source.GetBufferAsync(this.length).ConfigureAwait(false);
buffer = EndianByteBuffer.Create(buffer, source.Endian, this.fragmentItem == 1 ? 4 : this._vr.UnitSize);
this.observer.OnFragmentSequenceItem(source, buffer);
this.parseStage = ParseStage.Tag;
}
return true;
}
private async Task <bool> ParseValueAsync(IByteSource source)
{
if (this.parseStage == ParseStage.Value)
{
// check dictionary for VR after reading length to handle 16-bit lengths
// check before reading value to handle SQ elements
var parsedVR = this._vr;
// check dictionary for VR after reading length to handle 16-bit lengths
// check before reading value to handle SQ elements
if (this._vr == DicomVR.Implicit || (this._vr == DicomVR.UN && this.isExplicitVR))
{
var entry = this.dictionary[this._tag];
if (entry != null)
{
this._vr = entry.ValueRepresentations.FirstOrDefault();
}
if (this._vr == null)
{
this._vr = DicomVR.UN;
}
}
if (this._tag == DicomTag.ItemDelimitationItem)
{
// end of sequence item
return(false);
}
while (this._vr == DicomVR.SQ && this._tag.IsPrivate)
{
if (!IsPrivateSequence(source))
{
this._vr = DicomVR.UN;
break;
}
if (IsPrivateSequenceBad(source, this.isExplicitVR))
{
this.badPrivateSequence = true;
this.isExplicitVR = !this.isExplicitVR;
}
break;
}
if (this._vr == DicomVR.SQ)
{
// start of sequence
this.observer.OnBeginSequence(source, this._tag, this.length);
this.parseStage = ParseStage.Tag;
if (this.length != UndefinedLength)
{
this._implicit = false;
source.PushMilestone(this.length);
}
else
{
this._implicit = true;
}
var last = source.Position;
// Conformance with CP-246 (#177)
var needtoChangeEndian = false;
if (parsedVR == DicomVR.UN && !this._tag.IsPrivate)
{
this._implicit = true;
needtoChangeEndian = source.Endian == Endian.Big;
}
if (needtoChangeEndian)
{
source.Endian = Endian.Little;
}
await this.ParseItemSequenceAsync(source).ConfigureAwait(false);
if (needtoChangeEndian)
{
source.Endian = Endian.Big;
}
// Aeric Sylvan - https://github.com/rcd/fo-dicom/issues/62#issuecomment-46248073
// Fix reading of SQ with parsed VR of UN
if (source.Position > last || this.length == 0)
{
return(true);
}
this.parseStage = ParseStage.Value;
this._vr = parsedVR;
}
if (this.length == UndefinedLength)
{
this.observer.OnBeginFragmentSequence(source, this._tag, this._vr);
this.parseStage = ParseStage.Tag;
await this.ParseFragmentSequenceAsync(source).ConfigureAwait(false);
return(true);
}
if (!source.Require(this.length))
{
this.result = DicomReaderResult.Suspended;
return(false);
}
var buffer = await source.GetBufferAsync(this.length).ConfigureAwait(false);
if (!this._vr.IsString)
{
buffer = EndianByteBuffer.Create(buffer, source.Endian, this._vr.UnitSize);
}
this.observer.OnElement(source, this._tag, this._vr, buffer);
// parse private creator value and add to lookup table
if (this._tag.IsPrivate && this._tag.Element != 0x0000 && this._tag.Element <= 0x00ff)
{
var creator =
DicomEncoding.Default.GetString(buffer.Data, 0, buffer.Data.Length)
.TrimEnd((char)DicomVR.LO.PaddingValue);
var card = (uint)(this._tag.Group << 16) + this._tag.Element;
lock (this.locker)
{
this._private[card] = creator;
}
}
this.ResetState();
}
return(true);
}
