Interlaced Video Playback

[David Bullard]

Hello,

I've got a project that has interlaced video as it's source - as in, it came from a BetaSP tape.  Without going into details, deinterlacing the video has been unacceptable - it's being worked on, but the chances are low it will work out.  So this leaves me with the option of preserving it as an interlaced source and letting the projector work from that.  

As such, I'm looking to output 480i from my rig.  I say rig and not Qlab because as I understand it, I won't be able to preserve the interlaced video via Qlab.  I may be wrong, and if there is a way, I'm all ears.  What I believe will be best to do is to play back via something like a Blackmagic SDI card or possibly a MOTU HDX-SDI - something that isn't a screen in the eyes of the computer.  

My current plan is to use Qlab as the primary controller and audio source (10 channels or so), and have it send out timecode of some form.

Now here's the question: does anyone know of software that can playback a video file to a card such as the ones I mentioned, that will chase timecode or similar?  In the past I've used VirtualVTR in a ProTools situation (when video playback on PT was very poor).  It seemed to be a good choice for that application, but are there better solutions out there?  

Thanks in advance for any thoughts

 -  David

[micpool]

If your video is being shown on a digital projector then it's going to be progressive by the time it hits the imaging chip anyway.

The projector will use a line doubler to convert an interlaced video. It can sometimes be the case that a projector will have a better de interlacer than some software de interlacing, but tje solution is probably better conversion software isn't it,

Mic

[David Bullard]

Right - the projector's deinterlace ability should be the better choice.  The trick is, how to deliver it to the projector as such?

[micpool]

My assumption (which might well be wrong) would be that having a facilities house transfer your Beta SP to progressive digital file  using a  box like a Blackmagic Design Teranex which costs more than a projector  is going to give better results than whatever is doing the de-interlace in your projector. If it's only 480i can the footage really be so demanding that it can't be converted using decent hardware.

Mic

[David Bullard]

You're correct about the Teranex being very good, and very expensive.  Unfortunately, the source material has a combination of standard interlace and 3:2 pulldown interlace - which severely confuses the Teranex, and it just, well, doesn't do anything.  

While I'm working on a solution to creating a progressive version of the video, I am also looking for a way to play it back as the interlaced video that it is.

[Pierre-Luc Brunet]

I am also looking for a way to play it back as the interlaced video that it is.

I know the source videos are in 480i but I wonder if using one of the Blackmagic UltraStudio card outputting through SDI at 1080i59.94 (and scaling up) or SD 29.97 NTSC would do it. I'm not sure if Interlaced SDI is the same as Composite Interlaced but I wonder.

Also note that MOTU video devices are not supported as far as I'm aware. Blackmagic devices are supported though.