Editing Exif Data using filename pictures

Question

I own more or less one thousand of pictures which don't contain the Exif Data. Because of I would restore at least the taken date using the filename, is there a way to edit those fields programmatically?

The filename is something like this: IMG_20130326_232320.jpg

Thank you for the attention!

Answer 1

Sure, you can do it quite easily with the exiv2 utility and some shell scripting on a *nix system.

Supposing you are in the directory containing the file you can do something like this:

for pic in *.jpg ; do
  date = $( echo $pic | cut -d. -f1 | cut -d_ -f2-3 )
  exiv2 -M"set Exif.Image.DateTime Ascii $date" $pic
done

This will store a "date_time" string in the DateTime field of the image. As you can see, the Exif.Image.DateTime field accepts an ASCII string, so you can do whatever processing you want to get a better looking date. In your example, the field would then contain the string 20130326_232320, but you can do pretty much whatever you want with a bit of parsing.

A (maybe better, depending on your needs) alternative to EXIF is using the IPTC format and the corresponding IPTC.Date and IPTC.Time fields, which requires a specific data format but are easier to understand by photo management programs.

The exiv2 man page specifies that the IPTC.Date format is YYYY-MM-DD, while the IPTC.Time format is HH:MM:SS+|-HH:MM (local hour plus local offset from UTC). You can set them in the same way, but it will require a bit more filename parsing, of course.

The exiv2 tool is also available for Windows, so if you know a bit of batch scripting it shouldn't be too hard to implement it there.