[MPlayer-users] [BUGREPORT] I/O errors on DVD playback (totem plays it fine)

[Alexander Roalter]

Reimar Döffinger wrote:
> Hi,
> On Thu, Sep 15, 2005 at 09:28:31AM +0200, vitko wrote:
> 
>>mplayer 1.0pre7 fails to play certain DVD, while totem plays it fine, see
>>attached mplayer and dmesg logs. (Debian Sid + Marillat's packages).
> 
> 
> This is probably a "copy protection". The right solution IMHO is making
> the kernel ignore read errors (don't know what is necessary for this)
> and use a large -cache option.
> Of course it would be possible to fix this by behaving 100% like real
> DVD players but I think that might not be worth the effort...

Hm, it might be worth the effort, at least do as the cell commands want 
it. My seinfeld DVDs have some sort of copy protection. Ignoring the 
read errors still does not deliver all the right video, since there are 
some chunks that ought not be played, but only skipped over (and 
sometimes, even jump back a few sectors or so, I'm not through with the 
VM command set)

still, I'm lacking a) explanation on how the thing works (decoding Cell 
Commands) and b) how to apply them in mplayer. I managed to get some 
cell command jumping (not parsing) into the play_title (or so) from the 
libdvdread package. If I'll understand these commands, I'll first try to 
patch them in the libdvdread package (better: play_title) (which is able 
to dump the video, so to have a temporary solution), and later on maybe 
put it into mplayer as well.

I think this may become much more of an issue with more and more DVDs 
getting this kind of protection, mostly from Columbia/Sony and also from 
german label Kinowelt.


Cheers,
Alex