How to enlarge signature png in thesis?

[hongwai1920]

I attempted to insert my own signature png file into the thesis template.
However, the displayed image is too small.
How can I enlarge it?
I tried \includegraphic but it returns an error.

[Chen Wang]

I guess your signature png has a large white margin?
You'd better crop you png file to fit your signature.

You may enlarge the display by change L502, however, it will move down the dashed line and your name (unbalanced with the left date), which looks not good.

[hongwai1920]

I modified the L502 to just \makebox[4cm]{#4} so that I can control the scaling of image at the main tex file.
It suits my purpose after such changes.