ADOBE AFTER EFFECTS: Forum Expressions Tutorials Creative Cloud

16 BIT v 24 BIT VIDEO SAMPLE RATE?

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Jessica Robbins
16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 6:13:57 pm

i have a client they think they know what they are doing and is asking me to make my video 24 bit versus 16 bit (he says his are 24 bit- and they are therefor "crisper").

I am under the impression is is referring to the audio bit rate and not video sample size.

I am basically having to export via after effects an uncompressed MOV, then encode as AVI in quicktime pro (uncompressed)- in which there are no settings for video sample rate.


How do i make my video 24 bit sample rate rather than 16 through after effects and quicktime pro?

I am not referring to the color depth of 8,16 or 32....
Thanks all!


Return to posts index

Kevin Camp
Re: 16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 6:34:24 pm

i have a feeling he is getting confused with 8 bit-per-channel and 24-bit images.. those are actually the same. 8 bpc (commonly called 8 bit in after effects circles) is 8 bits per rgb channel which makes a 24-bit image -- 8 bits of red + 8 bits of green + 8 bits of blue = 24-bit image (a 32-bit image has an additional 8-bit alpha channel included).

any 8 bpc renders are in 24 bit color, or 'millions' in the render settings.

your 16 bpc renders (if rendered to a codec that supports 16 bpc) are in 48 bit color, or 'trillions'...

note that there are not a lot of codecs that support trillions of colors. apple's lossless in only 8 bpc. some image sequences, like tiff support 16 bpc (tif supports 32 bpc too). avid's dnxhd is a free one that supports trillions, although it is a lossy codec. hopefully, one day, red giant will release digital anarchy's microcosm codec which was lossless and 16 bpc, but it's been a year now since they bought da, and they still haven't released it.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW


Return to posts index

Dave LaRonde
Re: 16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 6:35:04 pm

Sorry to have to say this, but it sounds like your client has his or her thumb up a very uncomfortable orifice. 16 and 24 bit sampling are indeed audio terms and not video terms.


To my knowledge, there is NO type of delivery codec for movies that goes beyond 10 bits per channel, uncompressed types included. Does the client want an image SEQUENCE, perhaps?

What are the client's other delivery requirements? From that, we may be able to dope out what this clueless person actually wants. Don't spare the details.

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA


Return to posts index


Jessica Robbins
Re: 16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 6:52:55 pm

Here is his email:

"Also, just curious but I’ve created some avi’s that have a frame rate of 29.97 & Video sample size of 24 bit instead of the 30 and 16 you have on yours. It seems as though mine are a little more crisp, can set up yours with those specs? I would think there would be any noticeable difference between the 29.97 & the 30 frame rates, but figure there is between the 16 & 24 Video sample size."


------------------------------------------------------------------

This is for a outdoor display sign that requires a 280 x 512 sq pixel size and only take uncompressed AVIs. I sent the client several tests and the only one that works "satisfactorily" is the render I make in after effects and then encode via quicktime pro to AVI (uncompressed). The manual itself only states in must be in 29.97/30 fps and uncompressed AVI. I even spoke to the manufactuered to see if there were in bitrates to stick to- and thay of course said "i dont think so."

This client is just one of those that really thinks he knows things about video and make me second guess myself. He says his images are "crisper" and I only assume they are crisper becuase they are rendered out on a PC>PREMIERE>AVI instead of what i do (MAC>QT PRO>AVI). I am also guessing that they are perfectly fine- as I see them on my computer here and they play great.

He has premiere and plays around with things. The manufacturer sent him this file and he opened it in premeiere and took a screen grab
(335_avifilespec.jpg.zip) See how it says "depth 24" (which from the above comments means it is 8 BIT? correct?

If you guys have any more advice on this subject- that would be great. I think it might come down to diplomatically explaining this to the client. And taking out my frustration on a punching bag.


Return to posts index

Dave LaRonde
Re: 16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 7:09:22 pm

In this particular case, the "24 bits" refers to the presence of an alpha channel. There are 8 bits for each channel: R,G,B,A. It does NOT refer to 24 bits for each channel.

You can ask the client, "That bit depth denotes the presence of an alpha channel. Can you tell me if it's Straight or Premultiplied?"

So you can give the client an uncompressed AVI with an alpha channel, once the client tells you whether to make straight or premultiplied. And you should be able to do it right out of AE. Since you have QT, it'll let you render uncompressed AVI's.

Never mind that the presence of an alpha channel is absolutely useless on an animated billboard, y'know?

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA


Return to posts index

Jessica Robbins
Re: 16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 7:15:57 pm

Thanks Dave and Kevin- wish me "luck" and thanks for the help as always.


Return to posts index


Kevin Camp
Re: 16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 7:19:53 pm

i don't have qt pro to test your method, but have you tried to 'export' the render via file>export>avi in ae.

if you do this you can click the avi settings and choose 'none' for the compressor and set the color to 'millions' (which is 24-bit color -- i did notice that mine defaults to 'thousands' which is 16-bit color) and uncheck the audio output.

send that to him and see if that gives him 24-bit in his info panel.

it may be that qt pro has a similar export avi setting and that is what is converting your renders to 16-bt color when creating an avi.

also, just to correct dave (not disrespect him), a 24-bit image is an 8 bpc image without an alpha channel. a 32-bit image is an 8 bpc image with an alpha channel ;)

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW


Return to posts index

Dave LaRonde
Re: 16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 8:48:00 pm

Y'know, sometimes basic multiplication and division is just beyond me.....

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA


Return to posts index

Alan Lloyd
Re: 16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 8:19:15 pm

That's the standard .avi file output for PPro - I know, because that's what I cut with.

You can output a regular uncompressed .avi file from After Effects and that's what you'd get.

Also, the only way to be certain your client's file output (or yours, for that matter) is "crisper" is for both of you to export the identical file from your respective applications of choice and compare them both, side-by-side, in two viewer windows on the same monitor. And make very certain it's a monitor you can trust.


Return to posts index


Dave LaRonde
Re: 16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 8:50:43 pm


Thank you VERY much for chiming in. Your knowledge trumps the floundering efforts of a couple of FCP guys any day.

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA


Return to posts index

Alan Lloyd
Re: 16 BIT v 24 BIT VIDEO SAMPLE RATE?
on Oct 20, 2009 at 10:31:48 pm

As I think about it (and you're very welcome, by the way!) a compressed file may look "crisper" under some circumstances, because of some type of edge (or other) artifacting, where an uncompressed file may be seen as softer because it's actually smoother/cleaner.

I have not tested this - as I said, side-by-side on the same monitor with the same file from different applications is the only real way to know for certain. Just a thought on re-reading things.



Return to posts index

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