Re: libdvdread reports invalid IFO files

The IFOs read fine when the disc is mounted as UDF.  I wrote a patch for 
libdvdread to check the BUP files if anything goes wrong and it fixed the 
problem.  I posted it to the dvd-devel list on sourceforge, but I can post it 
here too if people want.

Still, perhaps the UDF parser could be more robust because the linux UDF 
driver corrects the error and reads the files with no problem.  I'm going to 
look into this in the next few days.
-- 
Keith Lyon <[email protected]>

On Monday 15 March 2004 3:58 am, H}kan Hjort wrote:
> Sat Mar 13 2004, Keith Lyon wrote:
> > i've got 2 dvds (Futurama Volume 3, Discs 1 and 3) which libdvdread says have 
> > invalid IFO files.  One title on each disc won't play.  In both cases in the 
> > function ifoRead_VTS() the vtsi_mat structure is getting filled with garbage 
> > so there's some problem reading the disc.  However, when I mount the discs 
> > and manually check the IFO file, I can see that its valid, and the discs work 
> > in standalone DVD players.
> > 
> > I'm guessing the discs have some errors (although they're brand new) which the 
> > system UDF driver recovers from but libdvdread doesn't.  how can i fix this 
> > so the disk gets read correctly?
> 
> Well, new disc shouldn't have sector errors but if they really do I guess
> we should at least modify libdvdread to try the BUP (backup IFO files) when
> reading the IFO fails.
> I never added this since reading the IFO has always worked for us so far.
> 
> You sure that it's not something else (like CSS) causing the read errors?
> 
> Could you send me a copy of all the IFO and BUP files?  Or do they read ok
> when mounted?  Both as is09660 and as UDF?   libdvdread incudes a mini UDF
> parser.  If the UDF filesystem is broken but the iso9660 is ok, that might
> explain it.
> 
> I'll see if I can write up a patch to either libdvdread or Ogle to fall
> back to the BUP version when reading the IFO fails in a few days.
> 
> Regards