Copying from DVD copies with VHS defects

[Sammy Reed]

Several years ago, I copied my vast VHS collection with my DVD recorder. Some of the older material has that jitter and other defects that TBC's etc. are supposed to correct - if you're copying from a VHS tape.
Would I be able to use a TBC (or something) to straighten out these problems copying from the DVD copies, or am I stuck with them?

[sanlyn]

No. Timing defects can be corrected during the original playback/capture process only. But there's an oddity here. Several years ago, as you described the process, many big-name DVD recorders had at least a minimal line tbc in their circuitry (Panasonic, Pioneer, Toshiba, to name some). While these are not as powerful in their timing correction as VCR's with built-in tbc or higher-priced shop gear, those recorders did have a smoothing effect. But not all DVDR's had them. Of course, if timing errors from the tape player are especially severe, only pro gear can help. The worst offenders having practically ineffective line tbc's were combo DVD/VHS machines.

The TBC you describe is not the typical external frame-level TBC, which does has frame timing/audio sync capability and often defeats certain forms of macrovision. But full-frame tbc's have no effect on line sync errors within frames, which is where the wiggles and shimmer came from.

The disturbance that you describe occurs only during analog tape playback. There is no known correction for it after that analog timing error has been digitally encoded because, on digital playback, there are no analog mechanically-generated line timing errors of that magnitude-- unless there's something wrong with the digital player, of course.

[manono]

Would I be able to use a TBC (or something) to straighten out these problems copying from the DVD copies...

In a word, no.


The Avisynth script developed for what you want to do may or may not help:


http://forum.doom9.org/showthread.php?t=162726