mplayer-gui error : Error in skin config file

After installing mplayer-gui package, I can't start it.

$ gmplayer

MPlayer 1.1-4.8 (C) 2000-2012 MPlayer Team

mplayer: could not connect to socket

mplayer: No such file or directory

Failed to open LIRC support. You will not be able to use your remote control.

Error in skin config file on line 6: PNG read error in /usr/share/mplayer/skins/default/main

Config file processing error with skin 'default'

After googling a bit, I found out that it was due to the png files in dir /usr/share/mplayer/skins/default. This is the default skin directory. To fix this error, I have to install ImageMagick package because I want to use the convert program to convert all of the png files to format png24. Thus,

cd /usr/share/mplayer/skins/default; for FILE in *.png ; do sudo convert $FILE -define png:format=png24 $FILE ; done

Rerun gmplayer and all should be fine.

Have fun!

UPDATE (02-10-2017)

It doesn't work on Ubuntu 16.04 (xenial) but there's a workaround here.

You can update your system with unsupported packages from this untrusted PPA by adding ppa:mc3man/mplay-skins to your system's Software Sources. (Read about installing) 

sudo add-apt-repository ppa:mc3man/mplay-skins
sudo apt-get update 

Now just upgrade the related package by running:

sudo apt-get upgrade 

Have fun!