Skip to main content

EXIF Writing in Python

How much does it suck to transfer a few hundred photos from your camera, only to afterwards notice the date on the camera was wrong? So, here I go looking for an EXIF batch updating program, and the pickings are much slimmer than I would expect. Of course, writing my own seems like a pretty viable option and the EXIF.py module would be grand to apply here, save for one problem: It was written in 2002 and it still doesn't write back to the image.

What's a dad with hundreds of family photos to do? Fix it. Talked with someone else interested in this and came up with three options to move forward.
  1. Replace the entire module with a ctypes wrapping over the libexif library.
  2. Jam EXIF writing into the existing module by invoking the exif command-line utility.
  3. Reverse engineer the EXIF format from the modules parsing functions and properly implement writing into the library.
Cross-platform support is great, but I'm having a crappy time trying to cross-compile the exif utility to windows, I can't find binaries for it, and that is some sand in my pants. Then again, I really wouldn't use it on Windows, so I can defer the search for the command line utility on Windows until later. For ease of implementation, this will probably be the route taken. I'll post the results here later, but I probably won't send patches to the maintainer, because the methods I'll use won't match well there. The current library isn't really designed well for this, so I think a redesign would be needed to do it in a really good way.

If anyone knows that this is futile and a solution already exists, please let me know.


Labels:

Comments

Cat said…
Take a look at this:

http://www.sno.phy.queensu.ca/~phil/exiftool/

It's not in Python but it might be just good enough to get the job done.
2:47 PM
Michael Urman said…
Did you try the cheeseshop? Pexif 0.8 looks likely to be useful.
2:57 PM
Unknown said…
Here are some options that work on Linux, not sure about cross platform.

Exiv2 claims to have been born because of the exact problem you want to solve.
http://www.exiv2.org/

I have used jhead before to extract info, but it also claims to be able to "relative adjust" timestamps.
http://www.sentex.net/~mwandel/jhead/
3:03 PM
Anonymous said…
Hmm, you sure its that good?

Ibiza
6:12 PM
mzt said…
https://pypi.python.org/pypi/piexif
4:56 AM
Post a Comment

Popular posts from this blog

CARDIAC: The Cardboard Computer

I am just so excited about this. CARDIAC. The Cardboard Computer. How cool is that? This piece of history is amazing and better than that: it is extremely accessible. This fantastic design was built in 1969 by David Hagelbarger at Bell Labs to explain what computers were to those who would otherwise have no exposure to them. Miraculously, the CARDIAC (CARDboard Interactive Aid to Computation) was able to actually function as a slow and rudimentary computer.  One of the most fascinating aspects of this gem is that at the time of its publication the scope it was able to demonstrate was actually useful in explaining what a computer was. Could you imagine trying to explain computers today with anything close to the CARDIAC? It had 100 memory locations and only ten instructions. The memory held signed 3-digit numbers (-999 through 999) and instructions could be encoded such that the first digit was the instruction and the second two digits were the address of memory to operat...
1 comment
Read more

Announcing Feet, a Python Runner

I've been working on a problem that's bugged me for about as long as I've used Python and I want to announce my stab at a solution, finally! I've been working on the problem of "How do i get this little thing I made to my friend so they can try it out?" Python is great. Python is especially a great language to get started in, when you don't know a lot about software development, and probably don't even know a lot about computers in general. Yes, Python has a lot of options for tackling some of these distribution problems for games and apps. Py2EXE was an early option, PyInstaller is very popular now, and PyOxide is an interesting recent entry. These can be great options, but they didn't fit the kind of use case and experience that made sense to me. I'd never really been about to put my finger on it, until earlier this year: Python needs LÖVE . LÖVE, also known as "Love 2D", is a game engine that makes it super easy to build ...
Post a Comment
Read more

Using a React Context as a Dispatch Replacement

React Contexts are the pretty little bows of the React world. Here's a really quick example of the kind of messy code you can cleanup by using contexts, without dragging in a larger dependency like Redux or even Flux. Starting backwards with a diff showing lines of code I was able to remove: All the properties I was able to remove were just pass-through. The Carousel component didn't care about any of them, but it had to pass through these callbacks so the multiple TaskList components inside the carousel could invoke actions. They were removed from the Component class itself, too, since it no longer needed to pass them through. Where did they all go? My ActionContext removed all the need for these passthroughs by providing a single simple helper method, action(), that components rendered under it can access.   I really enjoy the pattern of passing a single callback through a context and removing what used to be lots of callback properties. Of course, I cou...
Post a Comment
Read more