I connected a lib for cropping the picture, how can I upload the image to the site now?

Question

PHP

There are such libs

https://mattketmo.github.io/darkroomjs/
scottcheng.github.io/cropit

How to upload images to the server now?

So that you can pick them up in the $_FILES variable?

Answer 1

through $_FILES in any way.
see https://github.com/MattKetmo/darkroomjs
save: {
callback: function() {
this.darkroom.selfDestroy(); // Cleanup
var newImage = dkrm.canvas.toDataURL();
this variable contains the
string data:image/jpeg;base64,/9j/4AAQSkZJ
it can be passed to the server .
write a script that will accept it. parse and save to the right place,
but if you know js better than php, then you can
collect the correct post request to the server.