Adding new GPS ITD breaks file
File produced by unittest test_add_gps is broken as can be seen by looking at the next
parameter of the EXIF IFD after the test run
self.image_alt._segments["APP1"]._iter_ifd_tags("exif") # == 0x00060004
The block overlaps with the start of the GPS block and 0x0006 is actually the number of GPS properties, and 0x0004 the Tag ID of GPSLongitude.
It can also be seen in exiftool
's html dump
In this case the resulting image can be viewed and all metadata can be read, but in other cases unpacking the gps block in _app1_metadata.py/_add_tag()
can fail.