I was asigned a duty to make a design for T-shirts for the end of elementary/junior high school and I had to put our signatures on the back, so I took a graphic tablet and saved all people’s signatures as png. Now some of them have too narrow font and if I want it to be visible when printed on the shirts I have to make them more thick. Does anyone know how to make lines more thick (not necessary in krita) and would help me with this?
Hello @TheJupiterOne and welcome to the forum 
Try these replies to a similar topic:
Thickness of stroke - #5 by AhabGreybeard
Thickness of stroke - #7 by djwaterman
(You don’t need to install G’MIC nowadays. It’s included in krita.)
If they don’t help, explain why they don’t help and upload a full screen screenshot of a signature image opened in krita to give people a better idea of the nature of the problem.
Edit:Add: I’ve just remembered, there’s the Stroke layer style that can be used with lines on a transparent background and can turn this:
into this:
So, what is your initial situation with the signature images?
What do they look like?
@AhabGreybeard Thank you very much for your help! I finished the project before you told me about the other option which works with transparent background - that would’ve been usefull since all signatures were all just black ink on an alpha layer. But I worked it out anyway, I transformed them all from png to jpg with white background and then proceeded with the solution using filters that you suggested. It worked and our shirts are now ready for printing! I really am thankful for people like you on the forums, you DO know how to save lives! Appreciate the help and continue with your work!
Here are some pictures of before and after:
Our design was music-themed and the qr code only leads to our spotify playlist which is still under construction.
All the signatures you see on the bottom picture are already enhanced.