Feature #543

make exiv2 respect makernote offset that Microsoft WIC tools introduce when it edits photos

Added by Andreas Huggel about 9 years ago. Updated about 1 month ago.

Status:ClosedStart date:
Priority:NormalDue date:
Assignee:Robin Mills% Done:

100%

Category:withdrawnEstimated time:1.00 hour
Target version:0.26

Description

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
http://support.microsoft.com/kb/927527

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
(http://www.sno.phy.queensu.ca/~phil/exiftool/history.html) although
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.

makernoteoffset_original.JPG (421 KB) Redmine Admin, 13 May 2008 02:21

makernoteoffset_wicEdited.JPG (426 KB) Redmine Admin, 13 May 2008 02:21


Related issues

Related to Exiv2 - Feature #574: Support "Adobe Makernote" in DNGPrivateData New
Related to Exiv2 - Bug #779: Crash with unknown lens tags in DNG Closed 15 Jul 2011

History

#1 Updated by Summer - almost 9 years ago

Please find attached two photos.

makernoteoffset_original.jpg -> original jpg straight off the camera
makernoteoffset_wicEdited.jpg -> same jpg after it has been saved with WIC

#2 Updated by Andreas Huggel over 8 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?

Thanks.

#3 Updated by Andreas Huggel over 8 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 1 year 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 about 1 year 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".

#6 Updated by Robin Mills 12 months ago

  • Category changed from exif to withdrawn
  • Status changed from Assigned to Closed
  • % Done changed from 0 to 100
  • Estimated time set to 1.00

#7 Updated by Robin Mills 12 months ago

  • Target version changed from 53 to 0.26

#8 Updated by Robin Mills about 1 month ago

  • Subject changed from make exiv2 read the makernote offsetinterpret makernote offset that Microsoft WIC tools introduce when it edits photos to make exiv2 respect makernote offset that Microsoft WIC tools introduce when it edits photos

Also available in: Atom PDF

Redmine Appliance - Powered by TurnKey Linux