NTSC to PAL produces motion "stutter"... Avoidable?

VanLazarus wrote on 2/1/2005, 6:18 AM
Is there any way to prevent the "lurching" caused in motion when video is converted from a NTSC to PAL framerate? I have disabled "resampling" in Vegas 5 on my source NTSC video clip to avoid the horrible ghosting created when the frames are interpolated/blended, but this creates a "nearly as annoying" stutter on any video with significant motion... especially panning. I imagine there is no magic solution for this as it's just a product of the inconsistent rate of source frames selected to create the lower framecount in PAL.

What method do professionals use when converting movies shot in 24fps to NTSC and PAL for commercial DVDs? What do news broadcasters do when needing to air their video in both North America AND Europe?

I realize this is not necessarily a Vegas 5 specific question, but I'm new to video editing and still learning some of the basics.

Comments

Coursedesign wrote on 2/1/2005, 7:46 AM
There is some really nice hardware that does it in realtime. Snell & Wilcox Alchemist is #1 right now, for only $65k. Teranex also has really good stuff for this.

There are many companies who do these conversions for a living. The ones who do it for $20 per tape hour are just hooking up to cheap multistandard VCRs with ugly electronics.

The best is to find a company that has an S&W Alchemist, but make sure it's an Alchemist, not their cheaper models which are not close in quality.

For a very good software solution to use on your own, get Twixtor.

It doesn't run natively in Vegas though, you need Combustion or After Effects.
John_Cline wrote on 2/1/2005, 8:09 AM
The Canopus Procoder software does a very respectable job of PAL <> NTSC conversion.

John
taliesin wrote on 2/1/2005, 8:32 AM
I think both Twixtor and Procoder does format conversion same way like Vegas does - by interpolating frames. So - I don't see this is a disadvantage of Vegas. Made some conversions within Vegas in the past and them looked pretty fine. A bit of loss will always be there especially in the movement areas no matter which app will be used.

Marco
Pullmanite wrote on 2/1/2005, 8:59 AM
This isn't the easiest solution, but works very effectively. With some free tools and a bit of a steep learning curve, this is how I've done all my PAL-NTSC conversion.

VirtualDub and AVISynth handle the video frameserving and BeSweet handles the audio conversion. This method is great... it splits each frame into fields, resizes, then does the telecine to fix the framerate. The output is really beautiful and professional. Again, it takes a while to learn to use, but once you get AVISynth, BeSweet and the plugins installed, just copy the necessary script into Notepad, save it as an .AVS file, and open in VirtualDub.

http://www.geocities.com/xesdeeni2001/StandardsConversion/
Coursedesign wrote on 2/1/2005, 9:08 AM
Twixtor goes way beyond what Procoder or Vegas can do.

The difference is motion estimation.

Studio dude and author of several top 0.1% filmmaking books, S.D. Katz says "Twixtor synthesizes new frames by calculating a motion vector for each pixel. Essentially this is morphing at the pixel level. The method works in the majority of situations and produces excellent results."

You don't get that with Procoder or Vegas.

I agree that Procoder can generate surprisingly good results, but it's not close towhat Twixtor can do.
John_Cline wrote on 2/1/2005, 10:25 AM
Yes, Twixtor is pretty much the only way to create smooth slow motion. I've never used it for NTSC <> PAL conversion, I guess I should try that.

John