Fatal error Gallery

I activated the watermark for photos and when I want to upload or ERASE a photo I get this error:

Fatal error: Allowed memory size of 8388608 bytes exhausted (tried to allocate 1082881 bytes) in /home/macprop/public_html/mac-app/administrator/components/com_domus/assets/PHPImageWorkshop/Core/ImageWorkshopLib.php on line 121

From already thank you for your help !
Thanks

I went to: System Information -> PHP Info and search for "memory_limit". But I have no information there. It's blank.
There is another place where you can see?

Good afternoon, I spoke with my hosting provider, but I said the memory limit I can not change unless you change to a much more expensive plan.
Anyway, I wanted to try to upload photos and me two things happen:
When active the watermark, I skip the error that I said earlier and turn off when not out any errors, but I did not save any photo.
I do???
Greetings.