Rotate lots of image on Ubuntu

I often find myself with a bunch of images that are not properly rotated. Many cameras write the rotation information to the EXIF header of the image file, but the file itself is not actually rotated. Some photo editors do this automagically when you import the files, but I prefer to copy files manually to my drive.

I therefore have a little one-liner that can rotate all the files in a folder:

find . *.jpg -exec jhead -autorot {} \;

It works recursively, and is very quick!

Remove standard bookmarks in Nautilus

Yet another note to self on how to fix things in Ubuntu after a fresh install, found at askubuntu, this time to remove the standard bookmarks in the Nautilus file browser. I use a different setup of folders, and don’t really need these unused bookmarks. I wish it could have been easier to just right-click and delete to remove them (like for your own bookmarks), but it turns out to be a bit more tricky.

The default bookmarks are actually built from ~/.config/user-dirs.dirs, and this file is rebuilt on login from /etc/xdg/user-dirs.defaults. So it is necessary to modify both of the files, which may most easily be done with:

nano ~/.config/user-dirs.dirs

sudo nano /etc/xdg/user-dirs.defaults

In the nano editor you should comment out the ones that you don’t want.

And after a login the bookmarks are gone.

Move windows between screens on Ubuntu

As part of the fun of reinstalling an OS, you need to set up all the small things again (and you also get rid of all the small things you had set up and that you don’t need any longer…). This message is mainly a note to self about how to move windows between screens on Ubuntu with a key combination, found at stackexchange:

  1. Install CompizConfig Settings Manager:  sudo apt install compizconfig-settings-manager compiz-plugins-extra
  2. Run Compiz from the dash
  3. Click Window Management
  4. Enable the Put plug-in (select the check-box)
  5. Click on Put
  6. Configure the shortcut for Put to next Output (click enable). I like to use <super-less>, since that key combination is very convenient on a Norwegian keyboard
  7. Log out and back in to make changes take effect

Split PDF files easily using Ubuntu scripts

One of the fun parts of reinstalling an OS (yes, I think it is fun!), is to discover new software and new ways of doing things. As such, it works as a “digital shower”, getting rid of unnecessary stuff that has piled up.

Trying to also get rid of some physical mess, I am scanning some piles of paper documents. This leaves me with some large multi-page PDFs that I would like to split up easily. In the spirit of software carpentry I looked for a simple solution for splitting up a PDF file, and came across the command “burst” in the little terminal application pdftk. To use it on Ubuntu, you will first need to install it, using the terminal command:

sudo apt update && sudo apt install pdftk

Then this one-liner is all that is necessary to split a PDF file into a series of individual PDFs:

pdftk your-file.pdf burst

For convenience, I also made it into a small Ubuntu script:

This script can run by right-clicking on a file in the file manager:

And the end-result is a series of individual PDF files:

And then you can of course also combine the files again, either all PDFs:

pdftk *.pdf cat output newfile.pdf

or only the files you like:

pdftk file1.pdf file2.pdf cat output newfile.pdf