Exiv2 v0.27.3 Release

I’ve come back out of retirement to create Exiv2 v0.27.3. RC1 Preview is available from: https://pre-release.exiv2.org

The pre-release schedule is:
RC1: 2020-04-30
RC2: 2020-05-31
GM: 2020-06-30
The final release be posted on https://exiv2.org

I’d like to thank Phil, Sridhar, Luis, Kevin and Andreas S for working with me on this release. As always, I want to thank my wife Alison and cat Lizzie for their support.

Release notes: Exiv2 RoadMap · Issue #1018 · Exiv2/exiv2 · GitHub

I hope that Exiv2 v0.28 will be ready next year. If necessary, I will create Exiv2 v0.27.4 in 2021.


Can I just say, I truly despise the legal mechanism of software patents. They’re an assault on human thought. The only patents I can think of worse than software patents are patents on life itself patents on supposedly novel biological processes or sequences.

/end of rant.


Are you ranting about the cancellation of Support for ISOBMFF containers?.

I have been assured by private email that it’s incredibly unlikely that we would be in legal trouble by implementing that feature. However, it suited me to cancel that part of the project, as I had more time to focus on the Exiv2 documentation.

It would be good to add ISOBMFF to Exiv2 in the next 12 months. If we can find a volunteer to undertake the work, I will get professional legal advice to approve the change.


I read on your page: Adjust the Exif timestamp (that’s how it all started…)

But I can’t find any sample string for that.

I have actually two EXIF issues I like to fix:

Last holiday I didn’t change the time on my camera. Can I set all images to +5 hours from when they where taken? Right now the camera images do not line up with the phone images.

Other issue: manual lens data. This is blank in my camera. To have that bulk set would be handy.

Can I ask you to raise those issues GitHub - Exiv2/exiv2: Image metadata library and tools and the issues will be answered. To answer here, yes, you can set the photos DateTime forward/back with the -a option. In the man page $ man exiv2, it says:

option [arg]	long option  description
-a  tim	--adjust     Modify time stamps.  [+|-]HH[:MM[:SS[.mmm]]]

Manual lens? There is no meta data. Lens recognition is a continuous headache. Storing the lens isn’t defined by Exif. The manufacturer usually stores a “LensID” in the makernotes. So how to update the lens in the metadata depends on the camera manufacturer. When you report this, please add a sample image from your camera when the manual lens is in use.

1 Like

@damonlynch I’m making good progress on my book which will include code for ISOBMFF. It’s based on the existing Exiv2/JP2000 code which is has been in Exiv2 since 2008.

The book is being illustrated with a program called tvisitor.cpp which is modelled on the TiffVisitor code in Exiv2. It’s currently 2500 lines of C++. I hope tvisitor.cpp is easier to understand than the 100,000 lines in Exiv2. It has parsers for JPEG, PNG, TIFF (including BigTiff, CR2, DNG and NEF), CRW, PSD, ICC, ISOBMFF (JP2, HEIC, CRW and AVI). I hope to document the remaining 5 or 6 formats supported by Exiv2.

I have .CR3 and .HEIC working. I can’t see how we could have a legal issue with this. We’re decoding Exif standard data from a file which is documented by ISO. How could that be illegal?

The book covers everything I know about metadata and Exiv2. If LGM happens in Rennes in 2021, I’ll offer to give a talk about the book and to run an afternoon workshop. And then I am finished with Exiv2/metadata/open-source.

Current draft (being updated daily) IMaEA