Print Page - QuickTime Color Representation in AVIFs/HEIFs

Title: QuickTime Color Representation in AVIFs/HEIFs
Post by: blue-j on July 12, 2022, 06:50:52 PM

Hey there,

I have a decoding for this field, if useful. Presently, the field quicktime:colorrepresentation outputs values like this:

quicktime:colorrepresentation nclx 9 16 10

Those 4 values are independent. They are kind of part of a struct, with a cardinality of 1.

So, "Color Profiles" in these files are

nclx
rICC
prof

or not present.

Then the three integers following signify "Color Primaries," "Transfer Characteristics" and "Matrix Coefficients."

Please find attached the decoding key.

References:

https://aomediacodec.github.io/av1-spec/av1-spec.pdf (https://aomediacodec.github.io/av1-spec/av1-spec.pdf)

https://www.digikam.org/api/heif_8h_source.html (https://www.digikam.org/api/heif_8h_source.html)
Lines 573 - 702

Title: Re: QuickTime Color Representation in AVIFs/HEIFs
Post by: Phil Harvey on July 25, 2022, 08:06:14 AM

Thanks. ExifTool 12.45 will add a set of conversions for these tags.

- Phil

ExifTool Forum

General => Metadata => Topic started by: blue-j on July 12, 2022, 06:50:52 PM