I am aware that I can purchase a key to unlock hardware accelerated MPEG-2 decoding for playing DVD's.
I was wondering if there is a functional _un_accellerated DVD player available in e.g. one of the XBMC distributions which actually work. I have an external DVD drive connected with USB (externally powered) and it would be nice if I could watch the very occasional DVD on it.
You could try and play individual files from the dvd using a player that supports software decoding, but from what people thathave tried it report, the cpu would be choked on this and performance would be sloppy.
To view the menus to, you would need to have libdvdcss compiled for the pi (it's available) and a player compatible. Last time I tried with mine it was hit and miss, but ymmv.
Still, a license would get you far with little expense. Trust me, it's not worth the hassle to go software and performance sucks.
To watch video files in a format for which there is no hardware acceleration, I have repacked them with ffmpeg and watched them afterwards. The packing step will probably be very slow, I got roughly 1 fps on the Pi. I think this is doable for the video files on a dvd as well.
I did not dig deeply into the ffmpeg options, but found that specifying the output format as mkv worked well for me.
ffmpeg -i input.avi output.mkv
