Split ExifDirectory into sub directories to avoid tag collisions #17
Description
Currently Metadata Extractor merged IFD0, Exif SubIFD and IFD1 into
ExifDirectory.
It turns out that IFD0 (main image) and IFD1 (thumbnail image) use some of the
same tags, and so the thumbnail values are overwriting values from the main
image.
Specifically:
0x0112 Orientation : Horizontal (normal)
0x011a X Resolution : 72
0x011b Y Resolution : 72
0x0128 Resolution Unit : inches
People are noticing that after rotating, the orientation may be incorrect, and
that the resolution is always reported as 72 (common for thumbnails).
The solution is to split ExifDirectory into ExifIFD0Directory,
ExifSubIFDDirectory and ExifIFD1Directory.
This will make it easier to support writing metadata back to files in future
too.
Original issue reported on code.google.com by drewnoakes on 2 May 2011 at 10:54