JHOVE inappropriately defaults the TIFF Exif Version tag to 0220

[pwinckles]

JHOVE defaults ExifVersion to 0220 here. I assume that it does this because of this document. However, that document is just describing the value that should be used when writing that field, assuming the then most recent version of the Exif spec. For comparison, version 2.3 of the spec states that the field should be defaulted to 0232. As such, it is inappropriate to default this field when reading.

[carlwilson]

A quick read here and I'm inclined to agree. This sentence seems fairly authoritative

Nonexistence of this field is taken to mean nonconformance to the Exif standard.

This raises the possibility of nonexistence and marks it as a validation issue, there's no mention of taking a default value. Merging #691 for the imminent 1.26 release candidate, thanks for the work.