Questions about Cineform and CS3

[Dorel Iordache]

I’m considering getting NeoScene (hobbyist budget here) to work with footage from my Canon HV30 but I have a few questions about the Cineform codec and Premiere CS3:

1. First of all I’m surprised that the Cineform playback in PP CS3 is marginally better than that of HDV native files… if fact, the difference is so small that it’s hard to tell when a Cineform source is playing versus the m2t stream. I understand that the Real Time engine is not included in the “Neo” line but my expectation from reading the forums is that even so the Cineform files should be playing smoother than HDV native. I have a Q6600 proc and 4GB of RAM, m2t files play decently well (well enough to edit without much frustration, although the audio cuts off sometimes) but definitely not real time... I was expecting Cineform to play noticeably better but it’s simply not the case. Is there any additional tweaking to be done with PP CS3 or what I described is pretty much the expected behavior without Cineform’s real-time acceleration? I’m using the Desktop mode @ 1440x1080 and 1.333 PAR, progressive.

2. There’s a noticeable color shift between the m2t and Cineform files. Basically I put the same clip in both formats on the timeline and when I switch back and forth between them the reds look different. Actually the entire histograms look slightly different, the red shift is just more visible with my test footage. Again, is this normal behavior or has something to do with my particular set-up?

3. What is the appropriate conversion to Cineform from HV30 30p material ? Since the progressive 30p from the HV30 is embedded into a 60i container should I set HDLink to deinterlace or not? If not deinterlacing is the resulted Cineform file still 60i with progressive frames in each field or straight 30p? And lastly, if the former is true, should the project in PP CS3 be configured in Desktop mode progressive or HDV 60i ? As you can see it’s not clear to me what actually happens during the conversion so I’m confused to what’s the best project setting in PP.

4. Lastly, I noticed that my converted Cineform files end up consistently 1 frame short in size compared to the original m2t source (as reported by PP CS3). What’s up with that?

Any help in making me better understand these basic issues is much appreciated!

Thanks,
Dorel

[David Newman]

1. Neo Scene's main markets are CS4, Vegas, and Elements, we not have may using Neo Scene for CS3, CS3 CineForm users are typically running Prospect HD. Neo Scene is not a full accelerator like the high-end tools, if the parent application is a little slow, a faster decoder doesn't help much. For the base Premiere on a modern PC decoding to full res. m2t or CineForm is likely similar (not for AVC-HD which is much slower than both.) The CineForm decoder is faster at a particular operation, partial resolution decodes. But Premiere CS3 is not very good at using that feature (CS4 got better,) draft playback mode can help, but for CS3 a professional user we recommend Prospect HD which 3-4 times faster (same codec just more efficient playback engine that using all the features of the decoder -- I know not in your budget.) Sony Vegas on the other hand is very good at using partial resolution decodes and sees significant performance gains using CineForm. Neo Scene adds CineForm AVI support for all common video packages, but each NLE has they own quirks. Neo Scene particularly useful for 24p in 60i and AVCHD/Canon VDSLR sources, you need at least Neo HD to get more cool features.

2. Speaking of quirks. Premiere is wrong with HDV color, always has been, it is using standard definion BT.601 colorspace for M2T HD decodes. The CineForm decodes are correct. If you have a camera that produces colorbars, if is immediately obvious that Premiere is broken for color (under CS3 and earlier.)

3. Don't de-interlace. Use a progressive project, and interpret footage as progressive. With Neo HD and above you can tell it to encode 60i as 30p, bypassing the need for interpret footage step.

4. No idea. We are using a different vendor MPEG decoder are I guess it is giving us one frame less. Might also depend of the camera model.

[Dorel Iordache]

Thanks David for the super fast, late Saturday evening reply !

1. That answers most of my questions, my main interest in getting your entry level app is in fact the codec itself because I can already see the advantage in the chroma upsampling even for minor color correction. Having a straight-forward pulldown removal process for the HV30 is a bonus too.

2. That makes sense, I actually thought the cineform colors were a bit more accurate -- the red was mostly from my son's jacket and I know the exact color well :)

3. So that means that with NeoScene the resulted file is still a 60i container and only Neo HD outputs a straight 30p file ?

cheers,
-d.

[David Newman]

3. Not really, CineForm always stored and compresses as frames, even for interlaced images. The issue is 60i data is still flagged that way, so a 30p timeline will likely force an unwanted de-interlace -- using interpret footage addresses this. Neo HD has a 30p mode, for some efficiency gains, but it wasn't necessary to add to Neo Scene for the reasons above.