What causes 'shaky' portions of video screen

dstrege8 · Member Joined: 29 Oct 2002 Location: Mesquite, TX

I'm wondering what causes the 'shaky' sections of certain screens. I'm making DVD's, converting from avi to mpg with TMPEGnc. On some screens (usually still shots included in the video) there are areas that flicker/shake. Not the whole pic, but just a collar or maybe a section on striped shirt. A lot of times where thin lines are part of the picture.

Can anyone tell me what causes them? I've tried higher bitrate settings in TMPEGnc and different filter settings but don't appear to be having any impact on the flickering.

It's not totally awful, but something I would like to correct if it is possible.

Thanks in advance.

SingSing · Member Joined: 30 Apr 2001 Location: U.S.A.

Are you using CDR/W ?
This can caused by dirty disc or head, or inferior player.

Check whether it happened on your computer or not ?

dstrege8 · Member Joined: 29 Oct 2002 Location: Mesquite, TX

I'm using DVD +R/+RW.

Player is a new Sony DVP-NS315.

Encoded with TMPEGnc at VBR 8K, 6K, 3K, with GOP set to 1-3-2 with max of 12. Clarity looks great. Just that somewhat constant flickering on different parts of some of the stills.

I've tried higher bit rates but have been running into problems with playback on some DVD players being jumpy in video and sound. I figure by slowing the rate down to 8/6/3, they would have a better shot at running smoothly. (Is that a correct assumption?) I also tried lower bit speed (5k) and file was rejected by SpruceUp and VideoFactory as 'invalid sampling rate'. Is there a minimum bit rate for dvds?

I'm just wondering about the shaky parts and if I can set anything that might help. Would upping the noise settings or anything help?

eprunner06 · Member Joined: 13 Apr 2001

I'm having this EXACT same problem ... has anyone found a solution to this? I too am in the process of testing out different bitrates...

Thanks!
-Eric

seizure_ · Member Joined: 28 Dec 2003

i too have this problem. I think its part of the compression

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dark_myuutwo · Member Joined: 08 Oct 2003

I have the same shaky problem when unsqueezing widescreen 16:9 video from original 720x480 source into 720x360 (MPEG-2). Help!

My shaky problem is picture kind of 'jumps' or jitters up and down in an odd pattern, especially if it's still!
It also happens when I convert widescreen MPEG-2 to letterbox 4:3 MPEG-1 VCD file too!

ronnylov · Member Joined: 29 Aug 2002 Location: Sweden

A TV is drawing the pictrure in an interlace pattern. Small details will flicker on the TV on a still picture. Lets say you have a shirt with horisontal stripes and the stripes aligns with the scan lines then it will start to flicker on the TV screen but look fine on a computer monitor. Maybe this is what you see?
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Ronny

dark_myuutwo · Member Joined: 08 Oct 2003

Yes, but you've got it the other way around...to some good extent

lordsmurf · Posted: Jan 09, 2004 16:23

That's a side effect from 720x480 video, normally not seen in 352x480 and 704x480 video.
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eprunner06 · Member Joined: 13 Apr 2001

Would deinterlacing help to minimize the problem?

cooljoe666 · Member Joined: 21 Dec 2003 Location: USA

Seems like using progressive with no filters might help.

Or,

Maybe there was an earthquake during encoding.

eprunner06 · Member Joined: 13 Apr 2001

When you say progressive with no filters does that mean at the encoding process you select progressive somewhere and do not apply the filters then? Also/Or do you need a progressive scan DVD Player to play these then?

Thanks
-Eric

Gazorgan · Posted: Jan 14, 2004 10:25