FORUMS: list search recent posts

24p SD upconvert to 720p issues

COW Forums : AJA Video Systems

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Tim McLaughlin
24p SD upconvert to 720p issues
on Nov 26, 2008 at 4:58:11 am

I have a bunch (40 or 50) Digibeta tapes that I will most likely need to be sourcing from over the course of the next year. They are all 24p (23.98) with standard pulldown inserted. Digitize on the whole second and all's well in standard def land.

But the last time I tried to upconvert this materal to 720p 23.98 with my Kona 3, it was horrendous. Either the material came in as slo-mo, or I ended up having to digitize at 720p 59.94 just to get the material in.

I just read Shane Ross' upconversion doc and while it was good -- what a tremendous pain in the butt to have to digitize at 59.94 and then use Compressor to remove the pulldown and set the framerate.

Not great when you have a client sitting behind you...

What the heck am I missing? Removing pulldown and upconverting at the same time can't be that tough for the Kona 3, right?

Or is this something for a Teranex box?

Tim McLaughlin
Avid and Final Cut Editor




Return to posts index

Jeremy Garchow
Re: 24p SD upconvert to 720p issues
on Nov 26, 2008 at 5:37:14 am

[Tim McLaughlin] "s. Either the material came in as slo-mo,"

That's because the Kona won't do frame rate conversions and it is basically writing a 23.98 playback header on 29.97 material which won't work for real time playback as you have seen.

[Tim McLaughlin] "What the heck am I missing? Removing pulldown and upconverting at the same time can't be that tough for the Kona 3, right? "

Yes, actually, it can. The Kona cannot remove pulldown and upconvert to 720p23.98 (or 1080 for that matter) in one go. It's just not possible with this or any capture card that I know of.

For your client, you can capture the material at 525 23.98 and use those clips in the 720p23.98 timeline, scaled up. You will then do your edit and conform the clips later. You can also use compressor to upconvert your 525 23.98 footage.

Jeremy





Return to posts index

Tim McLaughlin
Re: 24p SD upconvert to 720p issues
on Nov 26, 2008 at 4:19:09 pm

Well that bites... I thought going "525 23.98" to 720 23.98 would be easier (even though it's not really 23.98). Dang.

Thanks Jeremy.

If only I had $40k for a Teranex VC300...

Tim McLaughlin
Avid and Final Cut Editor



Return to posts index


Shane Ross
Re: 24p SD upconvert to 720p issues
on Nov 26, 2008 at 5:34:00 pm

Yeah, that is too much for any card to handle. NO card, even the Avid ones, don't do this. If the tape really was 23.98 then upconverting SD to HD at the same frame rate would do it. But since digibeta doesn't do that rate, you have to capture at 59.94 and convert. This is a process that is best done at night. Capture, then do a batch overnight convert in Compressor. All will be ready in the morning.

Worried about clients? Tell them that you need the tapes the day before they need you to start editing so that you can do this conversion. Even if you had a Terranex, you'd have to DUB first, then capture. The client would still be waiting around. Besides, I never capture with the client sitting there. I hope to have it all done before the client sits down.

IT also helps to have those 8 Core Intel Macs, and to use QMaster to set up all those processors to be shared when using COmpressor. Makes the conversion take very little time. Talking faster than realtime...200% realtime in my experience.


Shane



GETTING ORGANIZED WITH FINAL CUT PRO DVD...don't miss it.
Read my blog, Little Frog in High Def


Return to posts index

gary adcock
Re: 24p SD upconvert to 720p issues
on Nov 27, 2008 at 12:09:07 am

[Shane Ross] "Yeah, that is too much for any card to handle. NO card, even the Avid ones, don't do this. If the tape really was 23.98 then upconverting SD to HD at the same frame rate would do it."

Remember that even Avid DS Nitris uses the OEM version of the Kona3/ Xena 2K card we are talking about.

This is by far the best card on the market and with assorted variants of it at work as OEM partners with like Avid and Autodesk's Flame, lnferno and now Lustre solutions, it is amazing that the same hardware you can use in FCP actually power some of the highest end workflows available in video and film.



gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
http://library.creativecow.net/articles/adcock_gary/AJAIOHD.php




Return to posts index

Ramona Howard
Re: 24p SD upconvert to 720p issues
on Nov 27, 2008 at 3:01:57 am

Jumping in late here.

What your trying to do is all doable via a smart application. We(Rave) can handle 2:3 removal on the fly but this is done thru the software and not the AJA hardware as there is no assurance that the A frame is where the 2:3 will start, therefore the software needs to be flexible enough to be changed.

We do have a new product emerging that takes care of the type of situations you bring up rather nicely AND it ties to the AJA hardware so it appears to happen all in real-time. Watch for details after the first of the year.

Cheers,
Ramona
http://www.spectsoft.com



Return to posts index


Jeremy Garchow
Re: 24p SD upconvert to 720p issues
on Nov 26, 2008 at 5:36:29 pm

[Tim McLaughlin] "I thought going "525 23.98" to 720 23.98 would be easier (even though it's not really 23.98). "


Yeah, there's a couple of very crucial processing steps involved there and the Kona is an awesome card for an awesome price. If it was $40k, it'd be able to do it I'm sure. For now, you can remove the pulldown in real time and scale the clips (have you tried that yet, you might be surprised at the quality).

Jeremy


Return to posts index

Tim McLaughlin
Re: 24p SD upconvert to 720p issues
on Nov 26, 2008 at 5:45:37 pm

Thanks Shane, Jeremy.

Still adjusting to the new workflows...

Good to know that there's a way out.

Shane - when digitizing SD (with pulldown) and converting to HD in Compressor (DVCProHD 24p) - are you using the reverse telecine, or just a straight deinterlace?

Thanks again guys!

Tim McLaughlin
Avid and Final Cut Editor



Return to posts index

Shane Ross
Re: 24p SD upconvert to 720p issues
on Nov 26, 2008 at 5:49:45 pm

All the footage I dealt with was regular interlaced video from DV, Beta and digibeta. So we converted and just de-interlaced. If, however, this footage was film telecined to tape, I would then use the reverse telecine. BUT...if you capture at 59.94 I am not sure you can do that...I know FCP won't, nor CT. They want 29.97 material. I am not sure how Compressor would do this. Might bear testing. Capture a clip and see how it does.

Or do what Jeremy suggested...capture as SD, reverse telecine, then scale in FCP. Not the best, but decent. And there is always the possibility of using Compressor to upscale, or Instant HD from redgiantsoftware.com.


Shane



GETTING ORGANIZED WITH FINAL CUT PRO DVD...don't miss it.
Read my blog, Little Frog in High Def


Return to posts index


Jeremy Garchow
Re: 24p SD upconvert to 720p issues
on Nov 26, 2008 at 7:20:06 pm

[Shane Ross] "BUT...if you capture at 59.94 I am not sure you can do that"

No, it'd be all screwed up as the KOna would do a bit of deinterlace and then the cadence would be kind of screwy. I think it's best to capture @ 525 23.98 and then either scale it up in the FCP timeline or use Compressor for an upconvert to 720p23.98. I recently had to do this with some archival footage that was originally shot on film. I removed the pulldown on capture to make it 525 23.98 then I simply put it in the 720p23.98 timeline with Motion controls set to 'best' rendering. The quality was pretty damn good considering. I also ran it through Compressor for an up convert and it honestly wasn't really worth the time. The only advantage of doing that was the clips were now 720p native so there's no extra rendering in the timeline. For converting NON 23.98 material to 720p23.98 using Compressor yields very decent results with all options set to best in Compressor. I have been surprised by the quality of that workflow a number of times.

This is all my opinion though, your eyes and mileage may vary. To me, it's more important to get the cadence correct. If the movie plays back all jerky and weird, it's more noticable than a slight drop in resolution. Also, when you have the 23.98 525 material, scaling is pretty easy as you are taking a progressive file and scaling up in a progressive timeline, there's no fields to deal with and USUALLY results in a superior scale.

Hope this makes sense.


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]