re: jittery playback

sonicboom wrote on 8/1/2002, 7:05 PM

ok, sometimes i use track motion
and i notice - only with track motion - that my project will be jittery
i use track motion with picture in picture---split screen, spinning transitions etc
i called sf and they said i should resample the event i use track motion on
also, if it persists i can resample the entire project when i render it
this will take mega-hours no?
thus, i am now going to create and save my veg files to explore this situation more deeply
has anybody had this problem?
and did resampling solve the jittery rendered file?
also, i will render at BEST setting instead of GOOD
thanks inadvance
also, i formated my computer for the hundredth time - at least - so it isn't that
sb

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lynj wrote on 8/9/2002, 11:45 AM

Last night I went through all the steps suggested...resample, reduce interlace flicker, changing fields (which made the clip not play at all), and all the combinations of the above. I even had one person to say that I should stay on certain percentages, ie: 1/4, 1/2, etc. I tried that. I put all the clips at the same percentage. I have 3:29 of beautiful footage that plays great on the computer monitor, but flickers & jerks when I play it back on a TV monitor. I'm at the point of being afraid to invest in another program, because it may do the same thing.

The last note from SF seemed to say..OK so see there, it does work. OK, maybe it works in some situations, but why isn't it working for me and all these other people complaining about the same thing. I don't get ficker & jerkiness when I edit in analog. Why do I get it in Vegas? Is this just a digital thing that can only be cured by investing in an Avid sytem? I'm not saying there's not a cure...just help me find it so I can make something back on my investment in your product!

I've used Sound Forge & CD architect for years and love them. That's why I bought Vegas instead of Premier when I was ready to go digital with my video business.

SonyDennis wrote on 8/9/2002, 6:02 PM

Lyn:

All of mine work fine too, not just "that one".

I'd like to get to the bottom of this. Please send the .veg file to drdropout@sonicfoundry.com and we'll take a look at it. Tell us the spot on the timeline that isn't working to your satisfaction.

Thanks.
///d@

Control_Z wrote on 8/9/2002, 11:06 PM

Don't feel bad. I occasionally get this as well. Apparently there's some deeply hidden bug in VV3 that causes it to confuse the field order. When it crops up I too throw everything at it including progressive rendering which seems to make it passable.

Despite my best efforts I've never been able to reproduce the problem at will which makes it really tough for SF to track down.

Blackout wrote on 8/12/2002, 11:10 AM

Hi all,

i have "jittery playback" for mpeg files in certain areas of files. I generally get smooth playback until i suddenly get the picture flikkering with what looks like black frames inserted. It looks to me exactly like what Control_Z says, the frame order gets confused. This sometimes lasts for 20 seconds then restores to smoothness and full picture frames.

Its a 704x576 mpeg file, maybe thats the problem. But i installed vegas on a clean XP partition and it still did it, and played with all the "field order" and "Resampling" settings, no diff. The 704 mpegs work fine in Videostudio and other editors.

I can reproduce this really easily too...it seems to occur shortly after i make a split/edit in the video file in the timeline. Perhaps the splits are occuring inbetween I-frames or something? is there a way to set this?

Regards,
Blackout.

JJKizak wrote on 8/12/2002, 7:14 PM

Jittery playback is caused by a slight overlap of clips on the timeline.
expand your clips visually (+) to view the junction of the clips---select and
move apart then re-attach.

James J. Kizak

Blackout wrote on 8/13/2002, 12:05 PM

hi james,

thanks for your comments, unfortuantely this occurs with only a single video file in the timeline. It also occurs in the middle of the single video file. It is not what you describe.

regards,
blackout.

JJKizak wrote on 8/14/2002, 9:04 AM

I tend to look at the simple problems first and I do believe that
VV3 has some issues that need to be addressed and corrected. I am
infatuated with this software as I have dumped Pinnacle DC-2000
with Adobe 6.0c, which is not an easy thing to do. I am convinced
that VV3 will eventually iron out these difficulties.

James J. Kizak

Blackout wrote on 8/14/2002, 11:31 AM

Hi james, I agree...thanks for your comments here. If anyone who knows VV3 well enough to tell a bug from a "user error" problem and has some swing at SF would like me to send them my 704x576 PAL mpeg2 file to see the frame scramble/black dropouts for themselves pls drop me an email :

darrenglen@hotmail.com

and ill send you a cdr with it.

Regards,
darren.

lynj wrote on 8/15/2002, 4:06 PM

Dennis, I appreciate your concern and willingness to help with my slow motion problem. I revamped all the footage, started from scratch and then resampled plus checked reduce interlace flicker on all the clips. Low & behold, smooth play. Don't know what caused the problem on the other project...very likely me, but the problem seems to be solved.

One more question though, because almost all my clips are in slow motion on a lot of projects, is there a way to check the resample for a batch of clips rather than doing them one at a time? Is it possible to do it on all, then take it off on the few that don't need it? If not, maybe ya'll at SF would consider making it a default when velocity is changed, then you could opt out if you didn't want it. Would make things go a lot faster, since it seems it is almost always necessary when using slow motion. Thanks.

fuzzzzy wrote on 8/15/2002, 4:12 PM

Hi,
thats been my experience with jittery playback also.....
After trying all the various seetings and switches, I deleted the offending clip and reinserted it...lo and behold...jitter was gone!!!
I'm convinced there is a bug somwhere?

fuzzzzy

BillyBoy wrote on 8/15/2002, 4:30 PM

As I've mentioned several times in other threads, rarely a track can get corrupted. That's just my choice of words lacking a more technical explination of what happens.

What I mean is whenever something on a track shows weird behavior for either the whole track or sections of it, I just move the contents off the track then discard the whole track. I personally have only seen this on audio tracks. The simple procedure of adding a new track and doing a cut/paste of the events on the "bad" track cured the problem for me each time. Your mileage may vary.

SonyDennis wrote on 8/15/2002, 5:57 PM

If you are rendering to AVI, in the Custom template properties, there is a "Resample the frame rate of all video" checkbox on the Project page that will do that same thing as checking "resample" on all events. It isn't used where the frame rate matches.
///d@