problem after 'cut from here...'

[manfy]

i'm using latest DRMpro361 (but have seen similar issues with earlier versions):
- with 'cut from here' i'm removing some crap from one cell (screen-capture attached)
- everything works as expected in 'debug mode'
- everything works fine on PC (powerDVD7)
BUT
- on actual DVD player (pioneer; last year sony with same issue) the cut sequence is still there!! (no sound/picture of course - but 1 silent minute of blank video)

after some searching in vob's and iso's i guess that the root cause lies in the PTS codes in the vob-file (since VOBU timestamps for cell2 have not been adjusted by DRM).
i guess you've been trying to avoid PTS adjustment by creating separate VOBID for the second cell. however, for my DVD player this doesn't seem to work!

to double-confirm i tried all kinds of workarounds (import/export/manual vob adjust/ifoedit mock strips, etc). the only step that finally did the trick was demuxing and remuxing the PGC (which resulted in coherent PTS) and replacing the old cells with this new ONE using 'replace block..'

is there any chance that DRMP can change PTS's automatically??

rgds.m

[manfy]

hi dimad,

somehow i couldn't get this time stamp issue out of my head, so i snooped around a bit more in vob/ifo files and mpeg specs.....with success:

there's no need to rewrite PTS timestamps, however, there seems to be a need to clear the 'seamless playback' flag of the succeeding cell, since the video cut created a PTS discontinuity!!
i guess when 'seamless playback' is ON, the desktop DVD-player latches on to PTS codes and this causes the 'display' of cut portion. PC DVD-players like powerDVD, on the other hand, seem to prioritize and follow ifo-information.

according to mpeg specs (for transport stream) this way of handling by DVD-player is correct, since seamless branches must have consecutive PTS timecodes (...at least that's what i read out of it...)

bottom line:
for users who have similar issues:
make sure that 'seamless playback' is deselected on the cell that follows the modified cell (only necessary after 'cut from here' operation, but NOT for 'cut TO here' !! )

for dimad:
maybe you can OFF the seamless flag programatically for cells that succeed cut cells!? (...unless this creates other implications somewhere somehow some time...!???)

BTW: i'm rather new to these low-level mpeg details, hence most of my statements are assumptions and (more or less logical) conclusions, rather than actual knowledge... please treat accordingly...!

...thx for giving me time to figure this out by myself...
just kidding! i'd appreciate a confirmation of my assumptions, be it right or wrong. the result is OK - i verified that. but i'm also interested in: why!

rgds.m

[toaddub]

[manfy]

yes, true! in my previous cut one would not notice any seamless/non-seamless impact, so i tried out various cuts and flag settings in the movie PGC:
* i tried 'cut from here' with and without seamless flag and 'split block' in the middle of an active scene and setting seamless flag OFF

results:
* no noticable impact on PC with powerDVD7
* DVD player Pioneer DV-393: no impact/error at all !! ...ooops

my conclusions:
* seamless playback flag by itself does not seem to change video output. i guess it is just an info for the decoder to 'try harder' for seamless playback of a physically not seamless stream/splice (= info to increase playback buffer).
in my tests, the seamless flag OFF definitely did not cause any playback gaps by decoder.
* since the 'blackout error' did not show now on my Pioneer, it tells me that my initial problem might be limited to the Menu domain!
...but i gotta try out some more things here.
i'll be back.

rgds.m

[manfy]

so now i'm really frustrated....
it seems my initial problem is specific to my pioneer 393 player! and furthermore, different players seem to handle the dvd flags quite differently...!

anyways, for those people with similar issues (similar players) this might be useful:
i dusted off my old Sony DVP-NS730P to compare results with my current Pioneer DV-393

seamless playback flag set to OFF for physically seamless cells:
- Pioneer: seamless playback in all cases
- Sony:
* VMG Menu domain: seamless playback
* VTS domain and VTS menu domain: clearly noticable non-seamless playback when entering cell marked as non-seamless

'blackout display' of cell content after using DRM 'cut from here':
- Sony: no problem. correct playback.
- Pioneer:
* VTS domain and VTS menu domain: no problem. correct playback.
* VMG Menu domain: error occurs (and it's reproducible)
BUT ONLY if it is the only PGC in the VMG Menu (..or if it contains a 'jump to VTS menu' post command).
exact causes of error i'm not sure, i just know after i added a second PGC to Video manager AND after i changed the post command from 'jump to VTS menu' to 'link PGC2' the problem mysteriously disappeared (and when i undo the changes the problem is back!)!

bottom line:
alles scheisse!
but seriously, if you encounter similar problem, try to OFF seamless playback on succeeding cell (it worked for me) or simply avoid cutting video and hide PGC playback with 'hide all blocks'

toaddub,
thx for help & sorry for the bother, but maybe it helps with yr support to other users some time!

rgds.m

[CDR-Zone.COM]