[RESOLVED] Colorimetry values in a dgi file

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mparade
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[RESOLVED] Colorimetry values in a dgi file

Post by mparade » Sat Aug 18, 2018 4:25 am

I had some problem reading out the colorimetry values from a dgi file. It is not clear to me without assignments to the corresponding numbers.

E.g. Colorimetry 2 2 2 means undef/unknown for all three parameter or bt709?

Please help. I would like to feed the encoder with the correct parameters.

Thank you very much!

mparade

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admin
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Re: Colormetry values in a dgi file

Post by admin » Sat Aug 18, 2018 7:59 am

From the manual:

COLORIMETRY 2 2 2
The numbers on this line give the coded values for matrix_coefficients, transfer_characteristics, and colour_primaries, in that order.

For the meaning of the values, get the AVC spec:

https://www.itu.int/rec/T-REC-H.264-201704-I/en

and refer to tables E-3, E-4, and E-5.

So 2 2 2 means everything is unspecified. In practice if the video has HD resolution assume 709; if it has SD resolution assume 601.

I will update the DGIndexNV document to include this explanation.

mparade
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Joined: Mon Oct 13, 2014 7:45 am

Re: Colorimetry values in a dgi file

Post by mparade » Sat Aug 18, 2018 9:04 am

Thank you very much!

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admin
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Re: Colorimetry values in a dgi file

Post by admin » Sat Aug 18, 2018 10:42 am

You're welcome. Good luck with your projects.

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