Cineform and Alpha Channels at DVinfo.net

Mike Morrell · May 22nd, 2007, 09:08 AM

How do I convert an AVI or MOV with an embedded alpha channel to a Cineform file with Alpha using HDLink? Does the Cineform codec support Alpha?

Can I convert Microsoft DV .avi files into 10 bit cineform files for Prospect Editing in 720x480? I tried running some conversions but the files "stop" at certain points, very weird. Is there even a preset for 10 bit 720x480 DV exiting with Prospect 2k and Premiere Pro?

David Newman · May 22nd, 2007, 09:20 AM

If there is a preset for SD just create one, it is very easy, although I think Prospect HD does have a NTSC and PAL 4x3 preset.

No Alpha channel support yet.

Mike Morrell · May 22nd, 2007, 09:25 AM

Thanks David for the quick reply. Now I know about Alpha, I'd been trying to get this to work for a while now.

I'll look into the DV to Cineform SD conversion a bit more and fill out a support request if I continue not to be able to get it to work. At least I know that it should work. I think that 10bit 4-2-2 editing will be better for some of the editing that I do. Plus, if I edit in Cineform mode, I should be able to get AJA output for monitor preview instead of firewire preview.

Thomas Smet · May 22nd, 2007, 09:27 AM

I would love to see alpha channel support in Cineform. Right now when we want to render out material from 3D Studio Max or Lightwave we have to use a 32 bit RGB AVI file or a 32bit RGB quicktime file which can be very large. We tend to do a lot of motion graphics work and it sure would be nice if our rendering layers could work in realtime just as well as the Cineform material.

Cineform may even bring in a larger market share because graphic designers who never even touch a camera will want to use the codec for realtime HD graphics editing.

Mike Morrell · May 22nd, 2007, 09:32 AM

It would be nice to have alpha support for a compressed format like cineform. But I am not sure how technically feasible it is. I used to use HuffyUV (free)for AE renders with alpha. It cut down file sizes for .mov and uncompressed avi with alpha to about 1/2 I think. But HuffyUV coded would not work with Nucleo. So I theorize that it is difficult to create an optimized coded that also supports alpha and multi-threaded processing the way that AE works. I guess that we cannot have it all....

Kris Bird · July 19th, 2007, 04:31 AM

Alpha is just a 4th channel .. There's nothing magic about it, I presume that it's on cineform's list of TO DOs, we just don't know how far down the list ...

That's not to say that it's easy to 'compress', presumably the alpha channel on it's own will require nearly as much bandwidth as the RGB, but that's still better than uncompressed or huffYUV (we use the later).

May 22nd, 2007, 09:08 AM	#1
Mike Morrell Regular Crew Join Date: Jun 2003 Location: Norcross GA Posts: 119	Cineform and Alpha Channels How do I convert an AVI or MOV with an embedded alpha channel to a Cineform file with Alpha using HDLink? Does the Cineform codec support Alpha? Can I convert Microsoft DV .avi files into 10 bit cineform files for Prospect Editing in 720x480? I tried running some conversions but the files "stop" at certain points, very weird. Is there even a preset for 10 bit 720x480 DV exiting with Prospect 2k and Premiere Pro?

May 22nd, 2007, 09:20 AM	#2
David Newman CTO, CineForm Inc. Join Date: Jul 2003 Location: Cardiff-by-the-Sea, California Posts: 8,095	If there is a preset for SD just create one, it is very easy, although I think Prospect HD does have a NTSC and PAL 4x3 preset. No Alpha channel support yet. __________________ David Newman -- web: www.gopro.com blog: cineform.blogspot.com -- twitter: twitter.com/David_Newman

May 22nd, 2007, 09:25 AM	#3
Mike Morrell Regular Crew Join Date: Jun 2003 Location: Norcross GA Posts: 119	Thanks David for the quick reply. Now I know about Alpha, I'd been trying to get this to work for a while now. I'll look into the DV to Cineform SD conversion a bit more and fill out a support request if I continue not to be able to get it to work. At least I know that it should work. I think that 10bit 4-2-2 editing will be better for some of the editing that I do. Plus, if I edit in Cineform mode, I should be able to get AJA output for monitor preview instead of firewire preview.

May 22nd, 2007, 09:27 AM	#4
Thomas Smet Trustee Join Date: Mar 2004 Location: Milwaukee, WI Posts: 1,719	I would love to see alpha channel support in Cineform. Right now when we want to render out material from 3D Studio Max or Lightwave we have to use a 32 bit RGB AVI file or a 32bit RGB quicktime file which can be very large. We tend to do a lot of motion graphics work and it sure would be nice if our rendering layers could work in realtime just as well as the Cineform material. Cineform may even bring in a larger market share because graphic designers who never even touch a camera will want to use the codec for realtime HD graphics editing.

May 22nd, 2007, 09:32 AM	#5
Mike Morrell Regular Crew Join Date: Jun 2003 Location: Norcross GA Posts: 119	It would be nice to have alpha support for a compressed format like cineform. But I am not sure how technically feasible it is. I used to use HuffyUV (free)for AE renders with alpha. It cut down file sizes for .mov and uncompressed avi with alpha to about 1/2 I think. But HuffyUV coded would not work with Nucleo. So I theorize that it is difficult to create an optimized coded that also supports alpha and multi-threaded processing the way that AE works. I guess that we cannot have it all....

July 19th, 2007, 04:31 AM	#6
Kris Bird Regular Crew Join Date: Sep 2005 Location: UK Posts: 173	Alpha is just a 4th channel .. There's nothing magic about it, I presume that it's on cineform's list of TO DOs, we just don't know how far down the list ... That's not to say that it's easy to 'compress', presumably the alpha channel on it's own will require nearly as much bandwidth as the RGB, but that's still better than uncompressed or huffYUV (we use the later).