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Author Topic: Rec 709 Complex?  (Read 1661 times)

GrizzlyAK

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Rec 709 Complex?
« on: December 01, 2016, 08:16:37 PM »
Can anyone point me to instructions on the definition of the Rec 709 Complex Source Color option? Is it Rec 1886?

Thanks,
Shane

Terrence Meiczinger

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Re: Rec 709 Complex?
« Reply #1 on: December 02, 2016, 02:35:07 PM »
Rec 709 Complex uses the full calculation rather than approximation. Most application use the approximation method and you can't intermix. I haven't seen the specs on BT-1886 and am not familiar with it.

GrizzlyAK

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Re: Rec 709 Complex?
« Reply #2 on: December 05, 2016, 10:51:47 PM »
Thanks Terrence. When you say "you can't intermix", what exactly does that mean? If you encode one way you MUST decode using the same method?

BT 1886 can be found http://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.1886-0-201103-I!!PDF-E.pdf.

It is, basically, Rec 709 color space with a gamma of 2.4, although it somehow allows for the true increased black levels of real monitors. So, since my monitor is calibrated that way, I'm trying to understand how I can use OpenDCP to convert my footage into XYZ. Just assuming a gamma of 2.2 with Rec 709, I suspect, will not be what I ultimately want, but I don't know that for sure.

Shane

Terrence Meiczinger

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Re: Rec 709 Complex?
« Reply #3 on: December 15, 2016, 08:54:47 PM »
Yes, if you encode with approximated (simple) formula, you need to decode the same way. Otherwise, you will get a slight shift in gamma.

dcinemaforum.com

Re: Rec 709 Complex?
« Reply #3 on: December 15, 2016, 08:54:47 PM »