How to edit photos in DNG format?

Question

Image processing

How can I edit a DNG photo? With saving either in RAW or in DNG
Any program is interesting, except for adobe photoshop and lightroom.
I need to apply only watermark to the output dng file from the camera. You can edit in Lightroom, but you can't apply a watermark. You can open it in Photoshop and apply a watermark there, but how do you save it to DNG from there?

It is possible to convert a raw file from photoshop to dng, but these are crutches, and Canon's Digital Photo Professional does not understand this file.

Answer 1

Recommend this method:
But this will not help if the task is to fake a picture, as if it had already come from the camera with a watermark.
Most likely you have a misunderstanding with the customer: it is understood that the transfer of raw files always occurs without watermarks. If you want to protect your work, give away JPEGs or other traditional bitmap format. finally TIFF.