Step 1: download the Ubuntu 14.04 .deb file from http://pkgs.org/download/mencoder. If you used dpkg at this point to install this, you would run into dependency problems. Specifically, the packages libavcodec54, libavcodec-extra-54, libavformat54, libavutil52 and libswscale2 may not be installed on your system. However, you may have newer packages installed, or there may be newer packages available, that provide the same functionality. Therefore, we are going to modify the .deb file.
Step 2: find out what versions of these packages are already installed on your system:
apt-cache policy libavcodec*
(and likewise for the other packages) will tell you that. If none is installed, but one is available, say libavcodec56 has an installation candidate, install it (sudo apt-get install libavcodec56). Make a note of the version, i.e. the last two digits, of each package. Note, however, that you need either libavcodec54 or libavcodec-extra-54, not both.
Step 3: download a script called videbcontrol. It is available from here. You want to make it executable; and if you don't like vi you may edit the script, find the line that uses vi (line 35 of the current script), and change that to nano or any other preferred editor.
Step 4: run the videbcontrol script against the deb file:
videbcontrol mencoder_1.1+dfsg1_0ubuntu3_amd64.deb
Or whichever deb file you have downloaded. (You may need to specify path names here, but you don't need sudo). This will open the deb's control file. In it you will find a line with "Depends on:" listing the packages that I mentioned in Step 1. Now carefully replace the version numbers with the ones that you have actually installed in Step 2. Closing the editor will save the .deb file als a .modified.deb file.
Step 5: Install the modified .deb file using sudo dpkg -i mencoder[version].modified.deb . Hopefully, all the dependencies will be satisfied at this point.
Incidentally, this is how I installed the nixnote2 beta on my system, with more or less the same dependencies.
Best Answer
Take into consideration that the LATEST version of VLC which is the 2.0 right now (Using the PPA for it) has different mplayer, mencoder and other packages than the ones devede, openshot and other programs that use this tools need.
So if you are talking about the latest VLC being VLC 2.0 then you probably just changed several packages (mencoder, mplayer, ffmpeg..) with the ones that come with VLC 2.0. This will create a problem for programs like Pitivi, OpenShot and DeVeDe.
The only fix I know of is to delete VLC 2.0 and the PPA that brought it. After that update the repositories so the reflect the deletion of the VLC 2.0 PPA. Then install VLC again which will in this case reinstall all the packages that were removed or modified by VLC 2.0.
If any of this packages happens to stay just purge it then download it again. In this case you will only have the ones that officially come with Ubuntu so after installing them DeVeDe, OpenShot (in my case when I tested) and Pitivi should all work again.
A normal step to do this would be:
sudo apt-get purge vlcsudo apt-get updatesudo apt-cache show vlc| grep Version. It should say some version that starts with 1.x.sudo apt-get install vlcif not reboot that PC until she learns how things work around here (Just in case).This is how I did it to restore all the rest of the programs. If any of them say they are missing X package then just install it. For example if they say they are missing mencoder then
sudo apt-get install mencoder. Repeat for any package still missing after installing VLC 1.x