You will need png2ico
First you will have to download the png2ico source
Now you will have to download compile and install the program by issuing:
debian:~# wget http://www.winterdrache.de/freeware/png2ico/data/png2ico-src-2002-12-08.tar.gz
debian:~# tar -zxvf png2ico-src-2002-12-08.tar.gz...
debian:~# cd png2ico/
debian:/root/png2ico# make
debian:/root/png2ico# cp -rpf png2ico /usr/local/bin/
Convertion is pretty easy and it comes to executing simply:
debian:/home/hipo$ png2ico favicon.ico png_picture_to_convert.png
Note that your png_picture_to_convert.png has to be in a graphic dimensions of 16×16
That’s all now you should have your favicon.ico on your Linux created.