Deleting tags in: XMP XMP-*
Sorry, XMP-x:XMPToolkit is unsafe for writing
  Writing new tags after deleting groups: XMP XMP-*
Writing XMP-dc:Creator
Rewriting t/images/PNG.png...
  Editing tags in: PNG XMP 
  Creating tags in: PNG XMP 
  FileType = PNG
  FileTypeExtension = PNG
  MIMEType = image/png
PNG IHDR (13 bytes):
PNG bKGD (2 bytes):
  Moving tEXt from after IDAT (20 bytes)
PNG tEXt (20 bytes):
  Moving iTXt from after IDAT (443 bytes)
PNG iTXt (443 bytes):
  Deleting XMP
  Rewriting XMP
    + XMP-dc:Creator = 'Phil Harvey'
PNG IDAT (1 chunk, total 14 bytes)
  Warning = [minor] Text/EXIF chunk(s) found after PNG IDAT (fixed)
  Deleting tEXt that was moved (20 bytes)
  Deleting iTXt that was moved (443 bytes)
PNG IEND (end of image)