I already have the caja-image-converter option installed but it shows nothing.
Weirdly enough if you install nemo and nautilus converter it does show and work inside caja:
The solution is to install *-image-converter
sudo apt-get install *-image-converter
Reading package lists... Done
Building dependency tree
Reading state information... Done
Note, selecting 'nemo-image-converter' for glob '*-image-converter'
Note, selecting 'caja-image-converter' for glob '*-image-converter'
Note, selecting 'nautilus-image-converter' for glob '*-image-converter'
caja-image-converter is already the newest version (1.16.0-1+serena).
The following packages were automatically installed and are no longer required:
gyp libgoocanvas-common libgoocanvas3 libjs-inherits libjs-node-uuid
libkf5plotting5 libssl-dev libuv1 libuv1-dev python-pygoocanvas
Use 'sudo apt autoremove' to remove them.
Recommended packages:
nautilus nemo
The following NEW packages will be installed:
nautilus-image-converter nemo-image-converter
0 upgraded, 2 newly installed, 0 to remove and 459 not upgraded.
Need to get 42.5 kB of archives.
After this operation, 328 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://packages.linuxmint.com serena/backport amd64 nemo-image-converter amd64 3.2.0+serena [19.8 kB]
Get:2 http://archive.ubuntu.com/ubuntu xenial-updates/universe amd64 nautilus-image-converter amd64 0.3.1~git20110416-1ubuntu1.16.04.1 [22.7 kB]
Fetched 42.5 kB in 0s (97.7 kB/s)
Selecting previously unselected package nautilus-image-converter.
(Reading database ... 364378 files and directories currently installed.)
Preparing to unpack .../nautilus-image-converter_0.3.1~git20110416-1ubuntu1.16.04.1_amd64.deb ...
Unpacking nautilus-image-converter (0.3.1~git20110416-1ubuntu1.16.04.1) ...
Selecting previously unselected package nemo-image-converter.
Preparing to unpack .../nemo-image-converter_3.2.0+serena_amd64.deb ...
Unpacking nemo-image-converter (3.2.0+serena) ...
Setting up nautilus-image-converter (0.3.1~git20110416-1ubuntu1.16.04.1) ...
Setting up nemo-image-converter (3.2.0+serena) ...
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