Sergei’s blog on bugs, penguins and stuff

I’ve been to a great eurotrip with my friends lately. We got lots of great pictures taken on two digicams. But…

mistake nr 1: as we passed on from EET (Eastern European Time) to CET (Central European Time) only one camera had it clock corrected (-1 hour)

problem nr 1: we had photos taken at one place with one hour shift. This creates problems when viewing pictures on gThumb (and likely picassa or f-spot) which sorts photos by EXIF header DateTimeOriginal or simply putted by date-time picture was taken.
As result, while showing the pics to my family, ones that were taken later appeared before those taken earlier (eg you walking on a ship and then you boarding the ship -> wrong order, harder to tell stories)

problem nr 2: cameras gave the pictures different names. As result, pictures from one camera were in front of images from the other in the file manager (a minor problem)

solution: sort out the pictures with shifted time and find an EXIF editor to correct the time.

The great EXIF editor found was jhead (online man page).

First of all you install it in ubuntu with sudo apt-get install jhead or find it in your favourite package manager.

Then you move the photos with the wrong time to a separate folder, eg dump. Then, using a terminal, you navigate to that folder and run a command to correct the time. For example

cd Photos/MyTrip/dump
jhead -ta-1:00  *.jpg

This will shift the time in EXIF for all .jpg files one hour back. Refer to the man page for more options.
Move the files back from dump folder. Problem 1 solved!

Regarding problem number 2, you can run jhead -nf%m%d-%H%M%S *.jpg to change the pictures’ names to match the MMDD-HHMMSS.jpg format. This way pictures from both cameras will be sorted in the file manager by date-time taken.

Hope this post will help someone, ’cause it took quite a time to find a proper tool to solve the problem

UPDATE

It seems F-Spot has similar feature – select the photos, choose Edit -> Adjust time … -> Shift all photos by. But that was reported unstable at the moment (see comment #1)

But really (I mean it – RLY) F-Spot get’s sooo much in the way, it’s unbearable. And it saves comments/tags to local database, not the image itself Look here and here