Need help to apply camscanner's magic color effect on an existing PDF file

I am looking for an application or an online service that could basically apply the above mentioned filter or something like to to an existing PDF file ( I do not have the images ) so the document that i have looks like this and i want it to be converted to something like this later.

PS : I did try to find a service an app or a site that can do this for me, but could not find one I know I could do it using Open CV or some other library but i don’t want to code something that long just for this, any and all abstraction and help would be greatly appreciated

if you have an android device then use adobe scan

idk whether u can import pdf in it probably it will. If not convert the pdf to image using pdf utils

then select those images(in adobe scan app) tap colour option choose whichever colour u want save it

thats it