private void ParseDataSet(long StreamPositionEnd, XElement theParentNode)
{
// Each Sequence does have it's own 'Private Code Dictionary'
PrivateCodeDictionary aPrivateCodeDictionary = new PrivateCodeDictionary();
while (mBinaryReader.BaseStream.Position < StreamPositionEnd)
{
DICOMDataElement aTag = GetNextTag(aPrivateCodeDictionary);
if (aTag != null)
{
// Check for 'Transfer Syntax UID (0002,0010)'
// ===========================================
if (aTag.Tag.Equals("(0002,0010)"))
{
mTransferSyntax = aTag.ValueField;
}
// Private Creator Code Handling
// =============================
// Reset Private Creator Code List if current Tag is 'Item'
if (aTag.Tag.Equals("(FFFE,E000)"))
{
aPrivateCodeDictionary.ClearPrivateCreatorCode();
}
// Add new Private Creator Code
if ((aTag.GroupNumber % 2) == 1 && (aTag.ElementNumber <= 0xFF))
{
string aGroupNumberString = aTag.GroupNumber.ToString("X4");
string aElementNumberString = aTag.ElementNumber.ToString("X2");
aPrivateCodeDictionary.LoadPrivateCreatorCode(aGroupNumberString, aElementNumberString, aTag.ValueField.Trim());
}
// Add new Tag to XDocument
// ========================
XElement newXDataElement = new XElement("DataElement");
theParentNode.Add(newXDataElement);
newXDataElement.Add(new XAttribute("Tag", aTag.Tag));
newXDataElement.Add(new XAttribute("TagName", aTag.TagName));
newXDataElement.Add(new XAttribute("VR", aTag.VR));
newXDataElement.Add(new XAttribute("VM", aTag.VM));
newXDataElement.Add(new XAttribute("Data", aTag.ValueField));
newXDataElement.Add(new XAttribute("Length", aTag.ValueLength.ToString()));
newXDataElement.Add(new XAttribute("StreamPosition", aTag.StreamPosition.ToString()));
// Call 'ParseDataSet' recursively for nested datasets
// ===================================================
if (aTag.VR.Equals("SQ"))
{
if (aTag.ValueLength == -1)
{
ParseDataSet(mBinaryReader.BaseStream.Length, newXDataElement);
}
else
{
ParseDataSet(mBinaryReader.BaseStream.Position + aTag.ValueLength, newXDataElement);
}
}
// End criteria for sequence reached?
// ==================================
// Break if current Tag is 'Sequence Delimitation Item'
if (aTag.Tag.Equals("(FFFE,E0DD)"))
{
break;
}
}
}
}
private string GetVR(UInt16 theGroupNumber, UInt16 theElementNumber, string theTag, PrivateCodeDictionary thePrivateCodeDictionary, VREncodingMode theTagVREncodingMode)
{
// For Tag 'Item (FFFE,E000)' return "Delimination"
if (theTag.Equals("(FFFE,E000)"))
{
return("DL");
}
// For Tag 'Item Delimitation Item (FFFE,E00D)' return "Delimination"
if (theTag.Equals("(FFFE,E00D)"))
{
return("DL");
}
// For Tag 'Sequence Delimitation Item (FFFE,E0DD)' return "Delimination"
if (theTag.Equals("(FFFE,E0DD)"))
{
return("DL");
}
if (theTagVREncodingMode == VREncodingMode.ExplicitVR)
{
// Explicit VR Encoding (value representation type is contained in stream)
// =======================================================================
byte b4 = mBinaryReader.ReadByte();
byte b5 = mBinaryReader.ReadByte();
return(string.Format("{0}{1}", (char)b4, (char)b5));
}
else
{
// Implicit VR Encoding (value representation type must be retrieved from dictionary)
// ==================================================================================
// For Tag 'Private Creator Code' return "Long String"
if ((theGroupNumber % 2) == 1 && (theElementNumber <= 0xFF))
{
return("LO");
}
// For 'Even Group Number' and 'Implicit VR Encoding', VR information has to come from public dictionary
if ((theGroupNumber % 2) == 0)
{
return(PublicDICOMDictionary.GetVR(theTag));
}
// For 'Odd Group Number' and 'Implicit VR Encoding', VR information has to come from private dictionary
if ((theGroupNumber % 2) == 1)
{
return(thePrivateCodeDictionary.GetVR(theTag));
}
}
// Should never be reached...
return("UN");
}
private string GetTagName(UInt16 theGroupNumber, UInt16 theElementNumber, string theTag, PrivateCodeDictionary thePrivateCodeDictionary)
{
// Tag 'Item (FFFE,E000)'
if (theTag.Equals("(FFFE,E000)"))
{
return("Item");
}
// Tag 'Item Delimitation Item (FFFE,E00D)'
if (theTag.Equals("(FFFE,E00D)"))
{
return("Item Delimitation Item");
}
// Tag 'Sequence Delimitation Item (FFFE,E0DD)'
if (theTag.Equals("(FFFE,E0DD)"))
{
return("Sequence Delimitation Item");
}
// For 'Even Group Number', DICOM attribute name has to come from public dictionary
if ((theGroupNumber % 2) == 0)
{
return(PublicDICOMDictionary.GetTagName(theTag));
}
// For Tag 'Private Creator Code' return "Private Creator"
if ((theGroupNumber % 2) == 1 && (theElementNumber <= 0xFF))
{
return("Private Creator");
}
// For 'Odd Group Number', DICOM attribute name has to come from private dictionary
if ((theGroupNumber % 2) == 1)
{
return(thePrivateCodeDictionary.GetTagName(theTag));
}
// Should never be reached...
return("???");
}
private DICOMDataElement GetNextTag(PrivateCodeDictionary thePrivateCodeDictionary)
{
DICOMDataElement aTag = new DICOMDataElement();
// Check, if we still read the 'File Meta Information' (attributes of type '(0002,xxxx)')
// For this purpose, we do a look-up of the GroupNumber with the default 'Little Endian' encoding mode
// If the GroupNumer is different to 0x0002, we have left the 'File Meta Information' section
// Don't forget to adjust the Stream Position afterwards (decrement by '2')
// Afterwars, the GroupNumber is read again (this time with the correct encoding mode)
ushort aGroupNumberLookup = GetUnsignedShort_16Bit(EndianEncodingMode.LittleEndian);
if (aGroupNumberLookup != 0x0002)
{
mFileMetaInfoReadingOngoingFlag = false;
}
mBinaryReader.BaseStream.Position -= 2;
// Set the Encoding Mode for this tag
// ==================================
// All 'File Meta Information Attributes (0002,xxxx)' shall be encoded as 'VR explicit, little endian'
// All other Attributes have to be encoded according to the transfer syntax value
VREncodingMode aTagVREncodingMode = VREncodingMode.Undefined;
EndianEncodingMode aTagEndianEncodingMode = EndianEncodingMode.Undefined;
if (mFileMetaInfoReadingOngoingFlag)
{
aTagVREncodingMode = VREncodingMode.ExplicitVR;
aTagEndianEncodingMode = EndianEncodingMode.LittleEndian;
}
else
{
switch (mTransferSyntax)
{
// Explicit VR Encoding, little endian
case "1.2.840.10008.1.2.1":
aTagVREncodingMode = VREncodingMode.ExplicitVR;
aTagEndianEncodingMode = EndianEncodingMode.LittleEndian;
break;
// Implicit VR Encoding, little endian
case "1.2.840.10008.1.2":
aTagVREncodingMode = VREncodingMode.ImplicitVR;
aTagEndianEncodingMode = EndianEncodingMode.LittleEndian;
break;
// Explicit VR Encoding, big endian
case "1.2.840.10008.1.2.2":
aTagVREncodingMode = VREncodingMode.ExplicitVR;
aTagEndianEncodingMode = EndianEncodingMode.BigEndian;
break;
// For every other Transfer Syntax (e.g. JPEG encoding), 'Exlicit VR, little endian' shall be used
default:
aTagVREncodingMode = VREncodingMode.ExplicitVR;
aTagEndianEncodingMode = EndianEncodingMode.LittleEndian;
break;
}
}
// Read GroupNumber
aTag.GroupNumber = GetUnsignedShort_16Bit(aTagEndianEncodingMode);
// Read ElementNumber
aTag.ElementNumber = GetUnsignedShort_16Bit(aTagEndianEncodingMode);
// Format the Tag string
aTag.Tag = string.Format("({0},{1})", aTag.GroupNumber.ToString("X4"), aTag.ElementNumber.ToString("X4"));
// Get VR value
aTag.VR = GetVR(aTag.GroupNumber, aTag.ElementNumber, aTag.Tag, thePrivateCodeDictionary, aTagVREncodingMode);
// Get DICOM attribute name
aTag.TagName = GetTagName(aTag.GroupNumber, aTag.ElementNumber, aTag.Tag, thePrivateCodeDictionary);
switch (aTag.VR)
{
case "OB": // Other Byte String
case "OF": // Other Float String
case "OW": // Other Word String
case "UN": // Unknown content
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-1
// -------------------------------------
// | Reserved | ValueLength | ValueField |
// -------------------------------------
// | 2 Bytes | 4 Bytes | n Bytes |
// -------------------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
// Skip the two Reserved bytes
byte ReservedByte0 = mBinaryReader.ReadByte();
byte ReservedByte1 = mBinaryReader.ReadByte();
}
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
// Parse out the data
if (aTag.ValueLength > 10)
{
for (int i = 0; i < 10; i++)
{
byte b = mBinaryReader.ReadByte();
aTag.ValueField += string.Format("{0} ", b.ToString("X2"));
}
aTag.ValueField += "....";
mBinaryReader.BaseStream.Position += aTag.ValueLength - 10;
}
else
{
for (int i = 0; i < aTag.ValueLength; i++)
{
byte b = mBinaryReader.ReadByte();
aTag.ValueField += string.Format("{0} ", b.ToString("X2"));
}
}
aTag.ValueField = aTag.ValueField.Trim();
aTag.VM = 1;
break;
}
case "UT": // Unlimited Text
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-1
// -------------------------------------
// | Reserved | ValueLength | ValueField |
// -------------------------------------
// | 2 Bytes | 4 Bytes | n Bytes |
// -------------------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
// Skip the two Reserved bytes
byte ReservedByte0 = mBinaryReader.ReadByte();
byte ReservedByte1 = mBinaryReader.ReadByte();
}
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
// Parse out the Value string using the Default Encoder
byte[] aBuffer = new byte[aTag.ValueLength];
mBinaryReader.Read(aBuffer, 0, (int)aTag.ValueLength);
Encoding myStringEncoder = System.Text.Encoding.Default;
aTag.ValueField = myStringEncoder.GetString(aBuffer).Trim();
aTag.ValueField = aTag.ValueField.Replace(Environment.NewLine, " ");
aTag.ValueField = aTag.ValueField.Replace(Convert.ToChar(0x00).ToString(), "");
aTag.VM = 1;
break;
}
case "SQ": // Sequence of Items
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-1
// ------------------------
// | Reserved | ValueLength |
// | 2 Bytes | 4 Bytes |
// ------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
// Skip the two Reserved bytes
byte ReservedByte0 = mBinaryReader.ReadByte();
byte ReservedByte1 = mBinaryReader.ReadByte();
}
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
aTag.VM = 1;
break;
}
case "AE": // Application Entity
case "AS": // Age String
case "CS": // Code String
case "DA": // Date
case "DT": // Date Time
case "LT": // Long Text
case "PN": // Person Name
case "SH": // Short String
case "ST": // Short Text
case "TM": // Time
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-2
// --------------------------
// | ValueLength | ValueField |
// --------------------------
// | 2 Bytes | n Bytes |
// --------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
aTag.ValueLength = GetLength_16Bit(aTagEndianEncodingMode);
}
else
{
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
}
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
// Parse out the Value string using the Default Encoder
byte[] aBuffer = new byte[aTag.ValueLength];
mBinaryReader.Read(aBuffer, 0, (int)aTag.ValueLength);
Encoding myStringEncoder = System.Text.Encoding.Default;
aTag.ValueField = myStringEncoder.GetString(aBuffer).Trim();
aTag.ValueField = aTag.ValueField.Replace(Environment.NewLine, " ");
aTag.ValueField = aTag.ValueField.Replace(Convert.ToChar(0x00).ToString(), "");
aTag.VM = 1;
break;
}
case "DS": // Decimal String
case "IS": // Integer String
case "LO": // Long String
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-2
// --------------------------
// | ValueLength | ValueField |
// --------------------------
// | 2 Bytes | n Bytes |
// --------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
aTag.ValueLength = GetLength_16Bit(aTagEndianEncodingMode);
}
else
{
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
}
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
// Parse out the Value string using the Default Encoder
byte[] aBuffer = new byte[aTag.ValueLength];
mBinaryReader.Read(aBuffer, 0, (int)aTag.ValueLength);
Encoding myStringEncoder = System.Text.Encoding.Default;
aTag.ValueField = myStringEncoder.GetString(aBuffer).Trim();
aTag.ValueField = aTag.ValueField.Replace(Environment.NewLine, " ");
aTag.ValueField = aTag.ValueField.Replace(Convert.ToChar(0x00).ToString(), "");
string[] split = aTag.ValueField.Split(new Char[] { '\\' });
aTag.VM = split.Count();
break;
}
case "UI": // Unique Identifier (UID)
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-2
// --------------------------
// | ValueLength | ValueField |
// --------------------------
// | 2 Bytes | n Bytes |
// --------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
aTag.ValueLength = GetLength_16Bit(aTagEndianEncodingMode);
}
else
{
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
}
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
// Parse out the Value string using the Default Encoder
byte[] aBuffer = new byte[aTag.ValueLength];
mBinaryReader.Read(aBuffer, 0, (int)aTag.ValueLength);
Encoding myStringEncoder = System.Text.Encoding.Default;
aTag.ValueField = myStringEncoder.GetString(aBuffer).Trim();
aTag.ValueField = aTag.ValueField.Replace(Environment.NewLine, " ");
aTag.ValueField = aTag.ValueField.Replace(Convert.ToChar(0x00).ToString(), "");
aTag.VM = 1;
break;
}
case "AT": // Attribute Tag
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-2
// -----------------------------
// | ValueLength | ValueField |
// -----------------------------
// | 2 Bytes | 4 Bytes fixed |
// -----------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
aTag.ValueLength = GetLength_16Bit(aTagEndianEncodingMode);
}
else
{
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
}
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
ushort aGroupNumber = GetUnsignedShort_16Bit(aTagEndianEncodingMode);
ushort aElementNumber = GetUnsignedShort_16Bit(aTagEndianEncodingMode);
aTag.Tag = string.Format("({0}),({1})", aGroupNumber.ToString("X4"), aElementNumber.ToString("X4"));
aTag.VM = 1;
break;
}
case "UL": // Unsigned Long (32 Bit, 4 Bytes)
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-2
// ----------------------------------------
// | ValueLength | ValueField |
// ----------------------------------------
// | 2 Bytes | ValueLength x 4 Bytes |
// ----------------------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
aTag.ValueLength = GetLength_16Bit(aTagEndianEncodingMode);
}
else
{
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
}
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
for (int i = 0; i < aTag.ValueLength; i += 4)
{
ulong Value = GetUnsignedInt_32Bit(aTagEndianEncodingMode);
aTag.ValueField += Value.ToString() + " ";
aTag.VM++;
}
break;
}
case "US": // Unsigned Short
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-2
// -------------------------------------
// | ValueLength | ValueField |
// -------------------------------------
// | 2 Bytes | ValueLength x 2 Bytes |
// -------------------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
aTag.ValueLength = GetLength_16Bit(aTagEndianEncodingMode);
}
else
{
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
}
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
for (int i = 0; i < aTag.ValueLength; i += 2)
{
ushort Value = GetUnsignedShort_16Bit(aTagEndianEncodingMode);
aTag.ValueField += Value.ToString() + " ";
aTag.VM++;
}
break;
}
case "SL": // Signed long (32 Bit, 4 Bytes)
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-2
// -------------------------------------
// | ValueLength | ValueField |
// -------------------------------------
// | 2 Bytes | ValueLength x 4 Bytes |
// -------------------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
aTag.ValueLength = GetLength_16Bit(aTagEndianEncodingMode);
}
else
{
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
}
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
for (int i = 0; i < aTag.ValueLength; i += 4)
{
long Value = GetSignedInt_32Bit(aTagEndianEncodingMode);
aTag.ValueField += Value.ToString() + " ";
aTag.VM++;
}
break;
}
case "SS": // Signed short (16 Bit, 2 Bytes)
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-2
// -------------------------------------
// | ValueLength | ValueField |
// -------------------------------------
// | 2 Bytes | ValueLength x 2 Bytes |
// -------------------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
aTag.ValueLength = GetLength_16Bit(aTagEndianEncodingMode);
}
else
{
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
}
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
for (int i = 0; i < aTag.ValueLength; i += 2)
{
short Value = GetSignedShort_16Bit(aTagEndianEncodingMode);
aTag.ValueField += Value.ToString() + " ";
aTag.VM++;
}
break;
}
case "FL": // Floating Point Single (32 Bit, 4 Byte)
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-2
// -------------------------------------
// | ValueLength | ValueField |
// -------------------------------------
// | 2 Bytes | ValueLength x 4 Bytes |
// -------------------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
aTag.ValueLength = GetLength_16Bit(aTagEndianEncodingMode);
}
else
{
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
}
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
for (int i = 0; i < aTag.ValueLength; i += 4)
{
float Value = GetFloatingPointSingle_32Bit(aTagEndianEncodingMode);
aTag.ValueField += Value.ToString() + " ";
aTag.VM++;
}
break;
}
case "FD": // Floating Point Double (64 Bit, 8 Byte)
{
// Reference: DCIOM Standard 2009, PS 3.5: Data Structures and Encoding
// Table 7.1-2
// -------------------------------------
// | ValueLength | ValueField |
// -------------------------------------
// | 2 Bytes | ValueLength x 8 Bytes |
// -------------------------------------
if (aTagVREncodingMode == VREncodingMode.ExplicitVR)
{
aTag.ValueLength = GetLength_16Bit(aTagEndianEncodingMode);
}
else
{
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
}
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
for (int i = 0; i < aTag.ValueLength; i += 8)
{
double Value = GetFloatingPointDouble_64Bit(aTagEndianEncodingMode);
aTag.ValueField += Value.ToString() + " ";
aTag.VM++;
}
break;
}
case "DL": // Special SQ related Data Elements Items:
// - (FFFE,E000) Item
// - (FFFE,E00D) Item Delimitation Item
// - (FFFE,E0DD) Sequence Delimitation Item
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
aTag.VM = 1;
break;
default:
aTag.VR = "UN";
aTag.ValueLength = GetLength_32Bit(aTagEndianEncodingMode);
aTag.StreamPosition = mBinaryReader.BaseStream.Position;
aTag.ValueField = "???";
aTag.VM = 1;
mBinaryReader.BaseStream.Position += aTag.ValueLength;
break;
}
return(aTag);
}
