jokiazhang / metadata-extractor

Automatically exported from code.google.com/p/metadata-extractor
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Support writing metadata back to files #66

Open GoogleCodeExporter opened 8 years ago

GoogleCodeExporter commented 8 years ago
Currently the metadata-extractor library provides a read-only view onto the 
metadata within files.

Several use cases would benefit from or require the ability to write data back 
to files, such as comments, GPS location, image orientation, image size...

The implementation of this feature is non-trivial. Not all types of metadata 
can or should be modified, and of course there is a high cost associated with 
bugs that occur when people are overwriting their files, should images be lost.

Given that the library supports many types of metadata, it's more realistic to 
roll out support for writing different types of metadata incrementally. The 
first type to be attempted should probably be Exif. Please comment if you 
disagree.

The first file type to be supported would likely be JPEG.

Original issue reported on code.google.com by drewnoakes on 30 Oct 2012 at 6:17

GoogleCodeExporter commented 8 years ago

Original comment by drewnoakes on 30 Oct 2012 at 6:21

GoogleCodeExporter commented 8 years ago
fair enough!

but especiall for RAW images I have currently no solution at all to write exif 
tags. even sanselan (very unsupported right now) can't do this... so that would 
be a real big benefit ;-)

Original comment by marcomoe...@gmail.com on 30 Oct 2012 at 6:24

GoogleCodeExporter commented 8 years ago
I guess I would start with supporting writing back fields that do not change 
the length of the field. That would already be helpful for a number of use 
cases (like changing the image orientation), and would not require rewriting 
the whole image -- only the actual changes would need to be written back.

Later, the library could detect whether or not it would need to rewrite the 
image, and keep the earlier version as an optimization.

I would not let the library bother whether or not a particular item should be 
modified or not -- that should be up to the users of the library to decide. One 
could of course add convenience methods for supported fields (again, like image 
orientation).

Original comment by axel.doe...@gmail.com on 26 Feb 2013 at 11:32

GoogleCodeExporter commented 8 years ago
cool that this is now on your list!
I have especially to write the user comment field and GPS data... that would be 
cool to have.

THX
-marco

Original comment by marcomoe...@gmail.com on 26 Feb 2013 at 11:41

GoogleCodeExporter commented 8 years ago
I'm wating for this feature very hard, too!

My needs are especially to write Title, Description, Tags and Faces in 
appropriate directories and fields.

Thanx for great library!

Original comment by srnjaksr...@gmail.com on 20 Apr 2013 at 9:58

GoogleCodeExporter commented 8 years ago
[deleted comment]
GoogleCodeExporter commented 8 years ago
I'm also waiting for this feature very bad !
I'm reading the EXIF orientation to rotate my photos in batch, and I need to 
change the orientation EXIF to avoid multiple rotations... Actually I still 
need the sanselan lib just for this...
Thanks and btw, great library !

Original comment by florian....@gmail.com on 26 Nov 2013 at 11:00

GoogleCodeExporter commented 8 years ago
This issue has been migrated along with the project to GitHub:

https://github.com/drewnoakes/metadata-extractor/issues/14

Original comment by drewnoakes on 19 Nov 2014 at 5:41