[MPlayer-users] Copy protection on DVDs beyond CSS?

[Ivo]

On Friday 21 April 2006 19:16, Jonathan Schmitt wrote:
> Hi,
>
> Am Donnerstag, 20. April 2006 22:51 schrieb Ivo:
> > Maybe it is just a weird flag that all players choke on, but could be
> > ignored (i.e. masked out). I don't know. Maybe add
> >
> > d->dsi_pack.dsi_gi.nv_pck_lbn &= 0xfffbffff;
> >
> > before the check in libmpdemux/stream_dvd.c (line 273) and see if that
> > fixes anything. But even if it works, this is probably not the right
> > fix
>
> thanks for the suggestion, it did improve the situation, however, it does
> not solve the issue. After several minutes of waiting, the dvd chapter is
> then played but not from the beginning. I estimate, the waiting time is
> roughly the time the film is already advanced.
>
> Playing it with -v gives now:
>
> DVD successfully opened.
>
> [...]
>
> DVD start cell: 0  pack: 0x0-0x35833
> DVD start=0 end=3602612
> STREAM: [null] dvd://1
> STREAM: Description: DVD stream
> STREAM: Author:
> STREAM: Comment:
> DVD Seek! lba=0x0  cell=0  packs: 0x0-0x35833
> DVD next cell: 1  pack: 0x35834-0x5A517
>
> !!! warning! reading packet while angle_seek !!!
> (warning line repeated for more then 120 times)
>
> Invalid NAVI packet! lba=0x40000  navi=0x80000

This looks like there are more "funny" bits there.

> !!! warning! reading packet while angle_seek !!!
> (warning line repeated for more then 140 times)

No idea what that means.

> Invalid NAVI packet! lba=0x40271  navi=0x80271
> [...]
>
> This repeats for around 6 million lines

Same here.

> I also get some of these:
> DVD next cell: 3  pack: 0x97C0C-0xBC36C
>
> and finally
> Angle-seek synced by cell/vob IDN search!
> system stream synced at 0x5E1C100D (1578897421)!
> ==> Found video stream: 0
> DVD Seek! lba=0x273F61  cell=12  packs: 0x2651F5-0x28DE89
>
> then several (all in all ~250)
> Invalid NAVI packet! lba=0x273F72  navi=0x2B3F72
> Invalid NAVI packet! lba=0x274036  navi=0x2B4036
> Invalid NAVI packet! lba=0x2740EA  navi=0x2B40EA
> Invalid NAVI packet! lba=0x2741B1  navi=0x2B41B1

That 2B part used to be 2F, but still doesn't match 27. You could try mask 
them all out, but I really doubt that is how this should be handled (change 
the mask to ... &= 0xffff).

> Angle-seek synced by cell/vob IDN search!
> DVD Seek! lba=0x36F7BF  cell=16  packs: 0x35D99E-0x36F8AE
> stream_seek: WARNING! Can't seek to 0x1B7BDFEE0 !
> DVD Seek! lba=0xBC382  cell=4  packs: 0xBC36D-0x12A294
> Angle-seek synced by cell/vob IDN search!
> MPEG-PS file format detected.
> ==> Found audio stream: 128
> Searching for sequence header... OK!
> After that, the video starts, however, the video is sometimes stuttering.

Probably because the navigation packets are not handled correctly and pieces 
are skipped, which might get worse if you mask out all the upper bits.

It would be helpful if you could provide a sample. I suppose mplayer 
-dumpstream doesn't work, but you said you could play it fine on some DELL 
windows computer. Maybe you could extract a small piece (1-5 minutes) of 
the DVD with something like DVD Shrink (but do not shrink, leave quality at 
100%), tar or zip it and upload it to ftp.mplayerhq.hu/incoming? Or with 
some other ripping program that supports a a partial extraction. Hopefully 
the ripping-program leaves those NAVI packets in tact and does not 
magically remove them (try with mplayer -dvd-device 
/dir/the/copy/is/located dvd://1 which should fail the same as playing the 
original DVD).

--Ivo