Aspose.Medical DICOM to Text Converter for .NET Knowledge Base
How to Convert DICOM to XML and Back using DicomXmlSerializer

How to Convert DICOM to XML and Back using DicomXmlSerializer

This tutorial demonstrates how to convert DICOM files to XML format and deserialize XML back to DICOM using C#. XML format is preferred for integration with legacy systems, HL7 workflows, and environments where XML tooling is well-established.

When to Use XML over JSON

  1. Legacy Integration:
    • Existing middleware and systems often expect XML format.
  2. HL7 Compatibility:
    • Healthcare systems using HL7 v2/v3 typically work with XML.
  3. XML Tooling:
    • Organizations with established XSLT transforms and XPath queries.
  4. Schema Validation:
    • XML schemas provide strict validation capabilities.

Prerequisites: Preparing the Environment

  1. Set up Visual Studio or any compatible .NET IDE.
  2. Create a new .NET 8 console application project.
  3. Install Aspose.Medical from the NuGet Package Manager.

Step-by-Step Guide to Convert DICOM to XML

Step 1: Install Aspose.Medical

Add the Aspose.Medical library to your project using NuGet.

Install-Package Aspose.Medical

Step 2: Include Necessary Namespaces

Add references to the required namespaces in your code.

using Aspose.Medical.Dicom;
using Aspose.Medical.Dicom.Serialization;

Step 3: Load the DICOM File

Load the DICOM file you want to convert.

DicomFile dcm = DicomFile.Open("patient_scan.dcm");

Step 4: Serialize to XML

Use the DicomXmlSerializer.Serialize method to convert to XML.

string xml = DicomXmlSerializer.Serialize(dcm.Dataset);

Step 5: Save the XML Output

Save the XML to a file for storage or transmission.

File.WriteAllText("patient_scan.xml", xml);

Step 6: Deserialize XML Back to Dataset

To convert XML back to DICOM, use the Deserialize method.

Dataset? dataset = DicomXmlSerializer.Deserialize(xml);

Complete Code Example: DICOM to XML Conversion

Here is a complete example for converting DICOM to XML:

using Aspose.Medical.Dicom;
using Aspose.Medical.Dicom.Serialization;

// Load DICOM file
DicomFile dcm = DicomFile.Open("patient_scan.dcm");

// Convert to XML
string xml = DicomXmlSerializer.Serialize(dcm.Dataset);

// Save to file
File.WriteAllText("patient_scan.xml", xml);

Console.WriteLine("DICOM converted to XML successfully!");
Console.WriteLine($"Output saved to: patient_scan.xml");

Complete Code Example: XML to DICOM Conversion

Here is a complete example for converting XML back to DICOM:

using Aspose.Medical.Dicom;
using Aspose.Medical.Dicom.Serialization;

// Read XML from file
string xml = File.ReadAllText("patient_scan.xml");

// Deserialize to Dataset
Dataset? dataset = DicomXmlSerializer.Deserialize(xml);

if (dataset != null)
{
    // Create DicomFile from Dataset
    DicomFile dcm = new DicomFile(dataset);
    
    // Save as DICOM file
    dcm.Save("reconstructed.dcm");
    
    Console.WriteLine("XML converted back to DICOM successfully!");
}
else
{
    Console.WriteLine("Failed to deserialize XML.");
}

Round-Trip Example: DICOM → XML → DICOM

Complete round-trip conversion demonstrating data integrity:

using Aspose.Medical.Dicom;
using Aspose.Medical.Dicom.Serialization;

// Load original DICOM file
DicomFile original = DicomFile.Open("original_scan.dcm");
Console.WriteLine("Original DICOM loaded.");

// Convert to XML
string xml = DicomXmlSerializer.Serialize(original.Dataset);
Console.WriteLine($"Converted to XML ({xml.Length} characters).");

// Save XML (for transmission or storage)
File.WriteAllText("intermediate.xml", xml);

// Later: Deserialize XML back to Dataset
string loadedXml = File.ReadAllText("intermediate.xml");
Dataset? reconstructedDataset = DicomXmlSerializer.Deserialize(loadedXml);

if (reconstructedDataset != null)
{
    // Create new DicomFile
    DicomFile reconstructed = new DicomFile(reconstructedDataset);
    reconstructed.Save("reconstructed_scan.dcm");
    
    Console.WriteLine("Round-trip complete: DICOM → XML → DICOM");
}

Example XML Output Structure

The XML output represents DICOM tags in a structured format:

<?xml version="1.0" encoding="utf-8"?>
<NativeDicomModel>
  <DicomAttribute tag="00080005" vr="CS" keyword="SpecificCharacterSet">
    <Value number="1">ISO_IR 100</Value>
  </DicomAttribute>
  <DicomAttribute tag="00080020" vr="DA" keyword="StudyDate">
    <Value number="1">20240115</Value>
  </DicomAttribute>
  <DicomAttribute tag="00100010" vr="PN" keyword="PatientName">
    <PersonName number="1">
      <Alphabetic>
        <FamilyName>DOE</FamilyName>
        <GivenName>JOHN</GivenName>
      </Alphabetic>
    </PersonName>
  </DicomAttribute>
  <DicomAttribute tag="00100020" vr="LO" keyword="PatientID">
    <Value number="1">12345</Value>
  </DicomAttribute>
</NativeDicomModel>

Comparing JSON vs XML Output

Size Comparison 

using Aspose.Medical.Dicom;
using Aspose.Medical.Dicom.Serialization;

DicomFile dcm = DicomFile.Open("sample.dcm");

string json = DicomJsonSerializer.Serialize(dcm);
string xml = DicomXmlSerializer.Serialize(dcm.Dataset);

Console.WriteLine($"JSON size: {json.Length:N0} characters");
Console.WriteLine($"XML size: {xml.Length:N0} characters");
// XML is typically 20-40% larger than JSON

Use Case Recommendations

ScenarioRecommended Format
New web servicesJSON
Legacy PACS integrationXML
HL7 middlewareXML
JavaScript frontendsJSON
XSLT transformationsXML
NoSQL databasesJSON
Schema validationXML

Integration with Legacy Systems

Example integration with legacy middleware:

using Aspose.Medical.Dicom;
using Aspose.Medical.Dicom.Serialization;
using System.Net.Http;
using System.Text;

DicomFile dcm = DicomFile.Open("patient_scan.dcm");
string xml = DicomXmlSerializer.Serialize(dcm.Dataset);

// Send to legacy SOAP service
using HttpClient client = new();
var content = new StringContent(xml, Encoding.UTF8, "application/xml");

HttpResponseMessage response = await client.PostAsync(
    "http://legacy-pacs/dicom/import",
    content
);

if (response.IsSuccessStatusCode)
{
    Console.WriteLine("XML successfully sent to legacy system!");
}

Troubleshooting

Handling Invalid XML

Wrap deserialization in try-catch for error handling:

try
{
    Dataset? dataset = DicomXmlSerializer.Deserialize(xml);
    if (dataset == null)
    {
        Console.WriteLine("Deserialization returned null.");
    }
}
catch (System.Xml.XmlException ex)
{
    Console.WriteLine($"XML parsing error: {ex.Message}");
}
catch (Exception ex)
{
    Console.WriteLine($"Deserialization error: {ex.Message}");
}

Character Encoding Issues

Ensure proper encoding when reading/writing XML files:

// Write with explicit encoding
using (StreamWriter writer = new StreamWriter("output.xml", false, Encoding.UTF8))
{
    writer.Write(xml);
}

// Read with explicit encoding
using (StreamReader reader = new StreamReader("input.xml", Encoding.UTF8))
{
    string xml = reader.ReadToEnd();
}

Large File Handling

For very large DICOM files, consider streaming:

using (FileStream fs = File.Create("large_output.xml"))
using (StreamWriter writer = new StreamWriter(fs, Encoding.UTF8))
{
    string xml = DicomXmlSerializer.Serialize(dcm.Dataset);
    writer.Write(xml);
}

Additional Information

  • XML format provides better human readability with proper indentation.
  • XML is more verbose than JSON, resulting in larger file sizes.
  • Consider compression for storing or transmitting large XML files.
  • Both JSON and XML support the same DICOM data types and structures.

Conclusion

This tutorial has demonstrated how to convert DICOM files to XML format and deserialize XML back to DICOM in C# using Aspose.Medical. XML serialization is essential for integrating with legacy healthcare systems and environments that rely on XML tooling and workflows.

 English