MPEG2 Anomaly

PeterMac wrote on 1/4/2004, 2:36 AM
Can anyone explain this?

I recently began a long put off exercise to convert some of my old Hi8 tapes to digital. The intention was to transfer them to the digital domain and from there to DVD.

The first stage - the A/D conversion - was carried out by replaying the tapes on a Sony Hi8 camcorder into a Canon XM2 (GL2) camcorder, which acted as the converter, capturing its output using the standard Vegas capture facility. The resulting AVIs were stored on the hard drive. So far, so good.

I then used Vegas to edit the parts worth keeping and to encode those parts into a number of MPEG2 files. The standard PAL template for DVD was used. (The new two-pass setting was not enabled).

DVD Architect was then used to test-burn a DVD with some of these clips. Again, standard settings were used with the one exception that I asked for AC3-2 encoding instead of the default PCM.

When the DVD was played on a stand-alone player into a TV, some - but not all - of the shots exhibited that strobing effect you get with the wrong frame order. Other shots are fine..!

Any ideas?

-Pete

Comments

farss wrote on 1/4/2004, 2:50 AM
First thing is to wokout where in the chain this is happening.
Try playing the same clips back from Vegas through the XM2 into the same TV. If is there next try playing the tapes straight form the Hi8 into the same TV. If its there maybe it got recorded that way or the tapes have degraded. If you can borrow a D8 camera and try using that.

If the problem is not in the Dv clips but is in the DVD I'm at a bit of a loss. If it is in the DV clips but doen't sem noticeable on the Hi8 tapes then the D8 camera / VCR may save the day.
PeterMac wrote on 1/4/2004, 6:07 AM
The fault complained of is a function of an 'incorrect' MPEG encoder setting, specifically: the field order. In this case it was the default 'bottom field first'
There would be nothing to gain from examining the original footage direct [into a TV] since the potential field order conflict doesn't exist until the footage is encoded/rendered.

The true problem is: 'why isn't this consistent?' Some parts of the same footage rendered OK, other parts didn't. The field order setting was left alone throughout.

-Pete
SonyEPM wrote on 1/4/2004, 7:08 AM
Peter Mac- you are testing the beta MPEG encoder yes? If so, email me the project please. md-drdropout<NOSPAM>@sonypictures.com
PeterMac wrote on 1/4/2004, 7:59 AM
Will do. Stand by.

-Pete