Comment by bayindirh

The images generated by SLR and mirrorless cameras are already signed with device embedded keys during EXIF embedding. Every manufacturer sells such verification systems to law enforcement or other institutions to verify such images.

Sometimes there are exploits which extract these keys from the cameras themselves, but I don't hear them nowadays.

One of the older products: https://imaging.nikon.com/lineup/software/img_auth/index.htm