media capture in mobile web and laptop

I don't know if I am in the right place but a friend recommanded this place. I am looking for a web page that opens laptop webcam or phone camera and allows to capture video stream then resize the capture

I have ound many examples that I tested but there is always something: sometimes it doesn't work on phones , most of the time I cant figure out how to add the crop option

so please could anyone help me here, it is for my internship and I am a noob

Thanks in andvance