Hello,
Since this is my first message on the forum, I would like to thank you for the brilliant LibRaw library that has enabled a bunch of different great uses.

On of them is developing Adobe DNGs, produced by smartphones.

However, many, if not all phones, use something that is called a "GainMap", basically a per-channel lens correction, that gains the data based on the embedded 2D image. This helps tremendously with strong Vignetting and hue shifts produced by the tiny lenses in smartphones.

I would love to have a way to either 'enable' or 'disable' it, or, worst case, extract it somehow. Could this be considered?

Page 115 of the Adobe DNG spec:
https://helpx.adobe.com/content/dam/help/en/photoshop/pdf/DNG_Spec_1_7_1...

It comes up as Opcode List# in Exif info.

Thank you very much in advance.