Exclude private content sequences from the original metadata table

The `getTags()` method still includes these sequences, but this just
keeps the original metadata table a little easier to read.
Private content sequences are detected by looking for a
private content creator, then excluding any sequences with a matching
high word. This corresponds to https://dicom.nema.org/dicom/2013/output/chtml/part05/sect_7.8.html

Author: melissalinkert

components/formats-bsd/src/loci/formats/dicom/DicomTag.java

@@ -719,6 +719,17 @@ else if (!(value instanceof long[])) {
     }
   }
 
+  /**
+   * See https://dicom.nema.org/dicom/2013/output/chtml/part05/sect_7.8.html
+   *
+   * @return true if this is a private content creator tag
+   */
+  public boolean isPrivateContentCreator() {
+    int highWord = (tag >> 16) & 0xffff;
+    int lowWord = tag & 0xffff;
+    return highWord % 2 == 1 && lowWord == 0x0010;
+  }
+
   @Override
   public String toString() {
     if (key == null) {

components/formats-bsd/src/loci/formats/in/DicomReader.java

@@ -37,9 +37,11 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableMap.Builder;
@@ -127,6 +129,8 @@ public class DicomReader extends SubResolutionFormatReader {
 
   private List<DicomTag> tags;
 
+  private Set<Integer> privateContentHighWords = new HashSet<Integer>();
+
   // -- Constructor --
 
   /** Constructs a new DICOM reader. */
@@ -368,6 +372,7 @@ public void close(boolean fileOnly) throws IOException {
       concatenationNumber = null;
       edf = false;
       tags = null;
+      privateContentHighWords.clear();
     }
   }
 
@@ -1168,6 +1173,10 @@ else if (infoString.startsWith("MONOCHROME")) {
    * rely upon the original metadata table.
    */
   private void addOriginalMetadata(String key, DicomTag info) {
+    if (info.isPrivateContentCreator()) {
+      privateContentHighWords.add(info.tag >> 16);
+    }
+
     if (info.value != null && !(info.value instanceof byte[]) &&
       !(info.value instanceof short[]))
     {
@@ -1179,7 +1188,8 @@ private void addOriginalMetadata(String key, DicomTag info) {
       }
     }
     if (info.attribute != PER_FRAME_FUNCTIONAL_GROUPS_SEQUENCE &&
-      info.attribute != REFERENCED_IMAGE_NAVIGATION_SEQUENCE)
+      info.attribute != REFERENCED_IMAGE_NAVIGATION_SEQUENCE &&
+      !privateContentHighWords.contains(info.tag >> 16))
     {
       for (DicomTag child : info.children) {
         String childKey = DicomAttribute.formatTag(child.tag);