/// <summary>
/// Creates an empty SQItem with no encapsulated data or child elements.
/// </summary>
public SQItem(DICOMElementSQ parentElem)
{
_parentElem = parentElem;
ElementsLookup = new SortedDictionary <uint, DICOMElement>();
Elements = new List <DICOMElement>();
lengthValid = false;
EncapsulatedImageData = null;
}
/// <summary>
/// Returns a new DICOMElement object of the correct VR, using the specified Group and Element
/// </summary>
/// <param name="group">A DICOM Group Tag</param>
/// <param name="elem">A DICOM Element Tag</param>
/// <param name="vr">A DICOM Value Representation (VR), a two character string</param>
/// <returns>A new DICOMElement encapsulating theh specified group, element, and VR.</returns>
public static DICOMElement CreateByVR(ushort group, ushort elem, ushort vr)
{
DICOMElement ret = null;
if (vr == DICOMElementAE.vrshort)
{
ret = new DICOMElementAE(group, elem);
}
else if (vr == DICOMElementAS.vrshort)
{
ret = new DICOMElementAE(group, elem);
}
else if (vr == DICOMElementAT.vrshort)
{
ret = new DICOMElementAT(group, elem);
}
else if (vr == DICOMElementCS.vrshort)
{
ret = new DICOMElementCS(group, elem);
}
else if (vr == DICOMElementDA.vrshort)
{
ret = new DICOMElementDA(group, elem);
}
else if (vr == DICOMElementDS.vrshort)
{
ret = new DICOMElementDS(group, elem);
}
else if (vr == DICOMElementDT.vrshort)
{
ret = new DICOMElementDT(group, elem);
}
else if (vr == DICOMElementFD.vrshort)
{
ret = new DICOMElementFD(group, elem);
}
else if (vr == DICOMElementFL.vrshort)
{
ret = new DICOMElementFL(group, elem);
}
else if (vr == DICOMElementIS.vrshort)
{
ret = new DICOMElementIS(group, elem);
}
else if (vr == DICOMElementLO.vrshort)
{
ret = new DICOMElementLO(group, elem);
}
else if (vr == DICOMElementLT.vrshort)
{
ret = new DICOMElementLT(group, elem);
}
else if (vr == DICOMElementOB.vrshort)
{
ret = new DICOMElementOB(group, elem);
}
else if (vr == DICOMElementOW.vrshort)
{
ret = new DICOMElementOW(group, elem);
}
else if (vr == DICOMElementPN.vrshort)
{
ret = new DICOMElementPN(group, elem);
}
else if (vr == DICOMElementSH.vrshort)
{
ret = new DICOMElementSH(group, elem);
}
else if (vr == DICOMElementSL.vrshort)
{
ret = new DICOMElementSL(group, elem);
}
else if (vr == DICOMElementSQ.vrshort)
{
ret = new DICOMElementSQ(group, elem);
}
else if (vr == DICOMElementSS.vrshort)
{
ret = new DICOMElementSS(group, elem);
}
else if (vr == DICOMElementST.vrshort)
{
ret = new DICOMElementST(group, elem);
}
else if (vr == DICOMElementTM.vrshort)
{
ret = new DICOMElementTM(group, elem);
}
else if (vr == DICOMElementUI.vrshort)
{
ret = new DICOMElementUI(group, elem);
}
else if (vr == DICOMElementUL.vrshort)
{
ret = new DICOMElementUL(group, elem);
}
else if (vr == DICOMElementUN.vrshort)
{
ret = new DICOMElementUN(group, elem);
}
else if (vr == DICOMElementUS.vrshort)
{
ret = new DICOMElementUS(group, elem);
}
else if (vr == DICOMElementUT.vrshort)
{
ret = new DICOMElementUT(group, elem);
}
else
{
ret = new DICOMElementOB(group, elem); //fall back to OB
}
return(ret);
}
//parseLen returns total bytes read
internal static DICOMElement Parse(ushort group, ushort elem, ILogger logger, TransferSyntax transferSyntax, SwappableBinaryReader br, SQItem parentSQ, bool skipOverData, out uint parseLen)
{
ushort vr;
uint len;
uint headerBytes = 0;
// Group 0 is always little-endian implicit vr, group 2 is always little-endian explicit vr
if ((transferSyntax.ExplicitVR && group != 0) || group == 2)
{
vr = br.ReadUInt16MSB();
headerBytes += 2;
if (vr == DICOMElementUT.vrshort || vr == DICOMElementUN.vrshort || vr == DICOMElementOB.vrshort ||
vr == DICOMElementOW.vrshort || vr == DICOMElementSQ.vrshort)
{
//next 2 bytes reserved
br.ReadUInt16();
headerBytes += 2;
//len is next 4
len = br.ReadUInt32();
headerBytes += 4;
}
else
{
//len is next 2
len = br.ReadUInt16();
headerBytes += 2;
}
}
else
{
//Look up VR in the dictionary
DataDictionaryElement dde = DataDictionary.LookupElement(group, elem);
if (dde != null)
{
//Found it.
vr = dde.vrshort;
}
else
{
//No idea... OB!
vr = DICOMElementOB.vrshort;
}
//Length will always be 32-bit here
len = br.ReadUInt32();
headerBytes += 4;
}
DICOMElement ret = null;
//Is it a compressed weirdo image data sequence that's actually an SQ?
if (len == 0xFFFFFFFF)
{
ret = new DICOMElementSQ(group, elem);
}
else
{
ret = CreateByVR(group, elem, vr);
}
ret.parentSQItem = parentSQ;
//Parse internal Data
parseLen = headerBytes;
try
{
// Can't skip over the length if it's not explicit
if (skipOverData && len != 0xFFFFFFFF)
{
parseLen += len;
br.BaseStream.Seek(len, SeekOrigin.Current);
}
else
{
parseLen += ret.ParseData(br, logger, len, transferSyntax);
}
}
catch (Exception e)
{
logger.Log(LogLevel.Error, "Exception in ParseData(grp=" + group + ", elem=" + elem + ", len=" + len + "): " + e.ToString());
}
return(ret);
}