make exiv2 respect makernote offset that Microsoft WIC tools introduce when it edits photos
|Assignee:||Robin Mills||% Done:|
|Category:||withdrawn||Estimated time:||1.00 hour|
is it possible to make exiv2 read the makernote offset
that Microsoft WIC tools introduce when it edits photos?
See this KB article for more detail
When I use Vista Photo Gallery to edit my photos - it moves the
location of the makernotes (to make room for new metadata?) and
records the offset of where it put them...but now exiv2
says "Warning: Failed to read Makernote, rc = 6" since it doesn't
know about the offset.
Whether this is a misguided approach or not by Microsoft (no argument
here!) it would be nice if it isn't too much work to make exiv2
compatible with these offset makernotes.
ExifTool added compatibility in 6.75
the author notes it was "ill-conceived" by Microsoft even so - Vista
is getting onto more and more desktops and more and more users will
have photos with these shifted makernotes (including me!) so it would
be nice to support the offset.
#2 Updated by Andreas Huggel about 10 years ago
Now this can be fixed quite easily. Unfortunately the sample doesn't have the new OffsetSchema tag set correctly; it is 0. (Exiftool can still make sense of the makernote, it has additional logic to guess the correct offset.) Do you have another picture with a proper value in the OffsetSchema tag (0xea1d) that you could attach?
#3 Updated by Andreas Huggel about 10 years ago
Phil recommends to ignore the tag: http://forums.dpreview.com/forums/read.asp?forum=1004&message=21930129
So maybe a more general algorithm to guess the offset would be better.
#4 Updated by Robin Mills over 3 years ago
- Subject changed from make exiv2 read the makernote offset interpret makernote offset that Microsoft WIC tools introduce when it edits photos to make exiv2 read the makernote offsetinterpret makernote offset that Microsoft WIC tools introduce when it edits photos
- Target version set to 53
#5 Updated by Robin Mills over 2 years ago
- Status changed from New to Assigned
- Assignee set to Robin Mills
This issue has been in the database for 8 years and nobody else has requested progress with this matter. So, unless you engage to persuade me to keep this matter alive, it will be closed on April 30 as "no longer needed/wanted".