Adobe-written keyword metadata not found in PNG image

[markolbert]

When I process a PNG file created by Photoshop, in which I've embedded keywords using Adobe Bridge, the keyword metadata is not found.

I used ExifTool to confirm the metadata is, in fact, in the file. It's in a tag that ExifTool calls "Subject".

When I process the file with ImageSharp and extract the XmpProfile from the metadata it reads (via a call to GetDocument(), which returns the raw XML for the metadata), the keywords are included in a node labeled Subject:

<?xpacket begin="" id="W5M0MpCehiHzreSzNTczkc9d"?>
<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="Adobe XMP Core 9.1-c002 79.a1cd12f, 2024/11/11-19:08:46        ">
  <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
    <rdf:Description rdf:about="" xmlns:xmpMM="http://ns.adobe.com/xap/1.0/mm/" xmlns:stRef="http://ns.adobe.com/xap/1.0/sType/ResourceRef#" xmlns:stEvt="http://ns.adobe.com/xap/1.0/sType/ResourceEvent#" xmlns:xmp="http://ns.adobe.com/xap/1.0/" xmlns:exif="http://ns.adobe.com/exif/1.0/" xmlns:tiff="http://ns.adobe.com/tiff/1.0/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:photoshop="http://ns.adobe.com/photoshop/1.0/" xmpMM:OriginalDocumentID="uuid:faf5bdd5-ba3d-11da-ad31-d33d75182f1b" xmpMM:DocumentID="xmp.did:8D3E99D35BA78A42BA55E1CBC779AC01" xmpMM:InstanceID="xmp.iid:0727cbc4-3d33-124e-8c8b-fa693d90a208" xmp:CreatorTool="Adobe Photoshop 26.8 (Windows)" xmp:MetadataDate="2026-01-02T10:49:54-08:00" exif:ExifVersion="0231" exif:PixelXDimension="6037" exif:PixelYDimension="4749" exif:ColorSpace="1" tiff:Orientation="1" tiff:ImageWidth="6037" tiff:ImageLength="4749" tiff:PhotometricInterpretation="2" tiff:SamplesPerPixel="3" tiff:XResolution="600/1" tiff:YResolution="600/1" tiff:ResolutionUnit="2" dc:format="image/png" photoshop:ColorMode="3" photoshop:ICCProfile="sRGB IEC61966-2.1">
      <xmpMM:DerivedFrom stRef:instanceID="xmp.iid:a7b7c5a2-e8ea-4a43-9f6a-1dcc92f3ed5d" stRef:documentID="adobe:docid:photoshop:be4ee987-67ea-3741-b9a0-9164f0e2b7e7" />
      <xmpMM:History>
        <rdf:Seq>
          <rdf:li stEvt:action="saved" stEvt:instanceID="xmp.iid:0727cbc4-3d33-124e-8c8b-fa693d90a208" stEvt:when="2026-01-02T10:49:54-08:00" stEvt:softwareAgent="Adobe Bridge 2026" stEvt:changed="/metadata" />
        </rdf:Seq>
      </xmpMM:History>
      <tiff:BitsPerSample>
        <rdf:Seq>
          <rdf:li>8</rdf:li>
          <rdf:li>8</rdf:li>
          <rdf:li>8</rdf:li>
        </rdf:Seq>
      </tiff:BitsPerSample>
      <dc:subject>
        <rdf:Bag>
          <rdf:li>farm</rdf:li>
        </rdf:Bag>
      </dc:subject>
    </rdf:Description>
  </rdf:RDF>
</x:xmpmeta>
<?xpacket end="r"?>

Is there a way to use MetadataExtractor to access this information? I'm guessing the comparable raw XML is available within the library, but not exposed publicly.