First writte by Hannah Bast on 16.10.2019
Without further ado, scanned signatures usually look very bad in PDF files. There are two problems, both of which make it painfully obvious that the signature was pasted.
1. The background is not transparent and one can clearly see the pasted rectangle containing the signature.
2. The resolution is bad and when zooming in a little (or even without zooming) one can clearly see the pixel.
These two problems can be solved as follows:
@1: This has to be solved while scanning, TODO: explain how
@2: This has to be solved when producing the PDF, TODO: explain how