What exactly does AspectHD do to HDV footage?

[Anthony Mwamwenda]

I have just discovered Cineform and their many products; so please bear with my noob question.

How can AspectHD change the Chroma Format of footage that was recorded as HDV? (See the Product Selector Guide Chart) As I understand it, HDV is recorded as 4:2:0; how can this be converted to 4:2:2 AFTER it has been recorded?

I am having a hard time understanding the Cieform site. Could someone please explain what this product does in very simple terms?

Thanks. I would apreciate any help I can get!

[David Newman]

Sorry about the site, it is needing an overhaul, as too much good info is now hard to find.

True you can't get a true 4:2:2 color space from a 4:2:0 source, yet you can do chroma interpolation and smoothing that fixes 4:2:0 artifacting for a more natural looking image. There is an old article on the website showing some of this : http://www.cineform.com/technology/H...ysis051011.htm

[David Taylor]

CineForm products convert out of camera source formats which typically introduce re-compression artifacts during a multi-generation post workflow. See https://www.cineform.com/technology/quality.htm for examples. CineForm solves these problems by offering a large "head room" on the converted files that maintains the original source quality.

With Prospect HD the resulting CineForm workflow is 10 bits in depth compared to Aspect HD at 8 bits. This adds extra precision which minimizes banding. See https://www.cineform.com/products/As...pect.htm#10bit.

We offer numerous pre and post processing features such as telecine removal for cameras that shoot 24p and embed the 24p in 60i, spatial resampling, speed change (25p to 24p conversion for instance), and deinterlacing to name a few.

And we can't forget to mention performance. The CineForm codec was optimized for very high multi-stream RT performance in Premiere Pro. Think of it like having a hardware accelerator card but performed in software. We are typically 2X-4X faster than native M2T editing depending on the performance of your machine.

We also offer cross-platform compatibility on Mac and Windows for those with a shared workflow.

Finally to your question of 4:2:0 to 4:2:2 - yes we do that upsampling during conversion. It is not possible to add chroma that did not exist, but by doing this conversion we are essentially over-sampling the orignal chroma ensuring that it does not further degrade. Also, when converted to 4:2:2 it is now consistent with traditional HD chroma signals.

[Anthony Mwamwenda]

Thank you Mr Newman! Thank you Mr Taylor!
Now I think I'm starting to get it! I'll read up some more just to make sure. This is really a great product!

One more question:
How does HDV footage that has been "CineFormed" by Prospect HD to 1920x1080 compare to footage captured by an Intensity card, with the CineForm codec, at 1920x1080?

[David Taylor]

Anthony, if you capture directly from your camcorder (HDMI out) through the Intensity card without going first to HDV tape, the HDMI feed is pre-MPEG compression and also has full 4:2:2 chroma when it hits the CineForm encoder. So the quality will be higher than if you first record to tape and then convert to Cineform. If you capture first to tape you have already hit the signal with MPEG compression and reduced the source chroma to 4:2:0.

It's not alway an option to record directly from the camera into CineForm without first going through tape, but for low-mobility shoots it is a great solution.

You observe zero difference between a CineForm recorded file compared to that same material recorded to disk uncompressed using Intensity. But you generally don't want to use the JPEG compression Blackmagic ships with Intensity as it is much lower quality than CineForm.

[Anthony Mwamwenda]

Thanks again. I appreciate your answer.