How to read dicom image metadata using dcm4che in Java

To read DICOM image metadata, we can use the dcm4che library.

First, we need to download and add the dcm4che library to our project. we can do this by adding the following dependency on our project's build file (e.g., pom.xml for Maven):

<dependency>
<groupId>com.github.dcm4che</groupId>
<artifactId>dcm4che-core</artifactId>
<version>3.4.1</version>
</dependency>

Now, let's create the java class to read the metadata from a DICOM file:

import org.dcm4che3.data.Attributes;
import org.dcm4che3.io.DicomInputStream;

import java.io.File;
import java.io.IOException;

public class DicomMetadataReader {

    public static void main(String[] args) throws IOException {
        File dicomFile = new File("/path/to/dicom/dicomfile.dcm");

        DicomInputStream dis = new DicomInputStream(dicomFile);
        Attributes metadata = dis.readDataset(-1, -1);
        dis.close();

        // You can now access the metadata using the get() method of the Attributes object.
        // For example, to get the patient's name, you can use:
        String patientName = metadata.getString(Tag.PatientName);
        System.out.println("Patient name: " + patientName);
    }
}

The dcm4che library provides many utility methods for parsing and manipulating DICOM metadata

How to update metadata for Dicom image

We can use the following example to update the metadata of a DICOM file

import org.dcm4che3.data.Attributes;
import org.dcm4che3.data.Tag;
import org.dcm4che3.io.DicomInputStream;
import org.dcm4che3.io.DicomOutputStream;

import java.io.File;
import java.io.IOException;

public class DicomMetadataUpdater {

    public static void main(String[] args) throws IOException {
        File dicomFile = new File("/path/to/dicom/dicomfile.dcm");
        File updatedDicomFile = new File("/path/to/updated/dicom/file.dcm");

        // Read the metadata from the DICOM file
        DicomInputStream dis = new DicomInputStream(dicomFile);
        Attributes metadata = dis.readDataset(-1, -1);
        dis.close();

        // Update the metadata
        metadata.setString(Tag.PatientName, VR.PN, "Patient name");

        // Write the updated metadata to a new DICOM file
        DicomOutputStream dos = new DicomOutputStream(updatedDicomFile);
        dos.writeDataset(metadata, dis.getTransferSyntax());
        dos.close();
    }
}

How to add metadata for the Dicom file.

import org.dcm4che3.data.Attributes;
import org.dcm4che3.data.Tag;
import org.dcm4che3.io.DicomInputStream;
import org.dcm4che3.io.DicomOutputStream;

import java.io.File;
import java.io.IOException;

public class DicomMetadataAdder {

    public static void main(String[] args) throws IOException {
        File dicomFile = new File("/path/to/dicom/file.dcm");
        File updatedDicomFile = new File("/path/to/updated/dicom/file.dcm");

        // Read the metadata from the DICOM file
        DicomInputStream dis = new DicomInputStream(dicomFile);
        Attributes metadata = dis.readDataset(-1, -1);
        dis.close();

        // Add the new metadata
        metadata.setString(Tag.PatientName, VR.PN, "Patient Name");

        // Write the updated metadata to a new DICOM file
        DicomOutputStream dos = new DicomOutputStream(updatedDicomFile);
        dos.writeDataset(metadata, dis.getTransferSyntax());
        dos.close();
    }
}