-
codec comparison
Is there a difference between a quicktime uncompressed 10 bit 422 file created on a mac, and an uncompressed 10 bit yuv 422 file created with a quicktime wrapper in after effects or premiere? I know there have been gamma issues between the computers, but is this the same codec or different?
Another question if you will, If you take an uncompressed 422 timeline, and render out an uncompressed file set to none, will the file be hurt in the process? I know it won’t gain any colorspace or anything(because the file is 422, and won’t get back the extra color info), but could there be a possible hit on the quality because it’s being changed?
-
4 Replies
-
[brett stumpp] “Is there a difference between a quicktime uncompressed 10 bit 422 file created on a mac, and an uncompressed 10 bit yuv 422 file created with a quicktime wrapper in after effects or premiere”
Sometimes, yes, since all “uncompressed” codecs are not created equal … for example, I work on both platforms so, if I render from AE on a Win machine using a Blackmagic “uncompressed” codec, I’d have to re-render in FCP since (in my case) the Mac uses an AJA “uncompressed” codec. So, I download an AJA uncompressed codec for Win from their website and install it on the Win machine, use it to render from AE and the file exactly matches the Mac’s AJA uncompressed codec.
I’m not sure I understand the second part, but I think the answer is no … despite the misleading term “none”, there is no such thing as using no codec at all so rendering an “uncompressed” codec timeline from your NLE to an “uncompressed” codec file shouldn’t lose anything unless the two use different “uncompressed” codecs. But as you already noted, you won’t regain anything either.
In other words, the bottom line is that what matters are the details of the “uncompressed” codecs you’re using and whether they are in fact the same regardless of their common “uncompressed” names.
-
Thanks David. Yeah, I wasn’t sure how to word that second question. I was trying to say If you have an uncompressed 10bit 422 file from mac, and render it in after effects as a quicktime file with the compressor set to none, is there going to be a hit to the file? My intuition is that it wouldn’t but wanted to hear other people’s thoughts on the matter.
-
There are a lot of resources on the web. Here’s one: https://www.crccheck.com/blog/2008/03/uncompressed-quicktime-plz/
Tip: when comparing two nearly-identical videos, drop one over the other in a comp, and set the transfer mode of the top one to Difference. If they are identical, you will see pure black, and when you move your mouse over the comp, there will be no activity in the info window: RGB values will all be 0,0,0.
The higher the values, the greater the difference between the two videos.
-
Thganks steve, I appreciate the help. I suspected there was going to be a bit of a difference, but wanted to hear what others had to say.
Still would love to know If I make a quicktime with none set as the compressor if it screws with my image, or just makes a larger file with the 422 information. Any ideas guys?
Reply to this Discussion! Login or Sign Up