JSFiddle - React, Tailwind, and code Playground
JavaScript
var sUrl = "http://ip_or_url:4773/image_renderer.service?action=resize&from_format=png&from_url=http://ip_or_url:4773/my_file.user.file&to_format=jpg&w=1920&h=1200";
var sFromUrl = sUrl.match(/from_url=[^&]*/)[0];
alert(sFromUrl);
var sBasename = sFromUrl.match(/[^\/]*$/)[0];
alert(sBasename);