I did not find on the Internet (I must little to be badly looked) a "thumbnailer" for files openEXR.
Then here is the solution that I set up...
ImageMagick must be installed. If it is not the case:
$ sudo apt-get install imagemagick
Then create the script which will be executed for the creation of thumbnails...
$ gedit /your/path/exr-thumbnailer
... here is the very simple code:
#!/bin/bash
convert "$1" -thumbnail "x$2" -colorspace sRGB -format png png:"$3"
Make it "excecutable":
$ chmod +x /your/path/exr-thumbnailer
It is then necessary to create a file or in /usr/share/thumbnailers, if you want that the other users take advantage of it (in this case it will be necessary to create it with the root privileges), or, if you are the only user, in .local/thumbnailers of your personal directory.
Attention: the directory thumbnailers in .local can be absent, in this case it is necessary to create it:
$ mkdir /home/your login/.local/share/thumbnailers
I chose the second solution:
$ gedit /home/your login/.local/share/thumbnailers/exr.thumbnailer
In the file exr.thumbnailer (with a dot in the name) put this:
[Thumbnailer Entry]
TryExec=/your/path/to/exr-thumbnailer
Exec=/your/path/to/exr-thumbnailer %i %s %o
MimeType=image/x-exr;
Change "your path" with yours.
Then restart nautilus:
$ nautilus -q; nautilus
Or restart your session.
The icons of files EXR should display images.
To open them, I use "Djv Imaging" which you will find here
Install it, then associate EXR files with executable file "djv_view" by means of UbuntuTweak for example.
It detects the images sequences .
Et voilà
