TIFF Tag DNGBackwardVersion
|Code||50707 (hex 0xC613)|
|Default||DNGVersion with the last two bytes set to zero.|
Used in IFD 0 of DNG files.
This tag specifies the oldest version of the Digital Negative specification for which a file is compatible. Readers should not attempt to read a file if this tag specifies a version number that is higher than the version number of the specification the reader was based on.
The DNG specification states that in addition to checking the version tags, readers should, for all tags, check the types, counts, and values, to verify it is able to correctly read the file. In our opinion, this applies to all TIFF decoding, not just DNG.