Ajax Image Upload

The task might be very simple for a professional. 1) I want a button "Select Images To Upload", and the invisible "file" input. Example: <button>Upload Images</button><input type='file' style='visibility:hidden' multiple> 2) Once I click on the button - JQuery should trigger the click on the input field (to let me select multiple files to upload). 3) Once I'm done selecting - it should upload the files to the PHP script on my server (can be same file). Example: $('myinputfield').change(form ajax) 4) The file submission should happen WITHOUT page reload (Real jQuery AJAX, no fake AJAX like target="invisible_iFrame" stuff, and no external scripts or finished open source solutions). On the PHP side received the files - for each file it should do following: - test if it is a valid image (gif, png, jpg, bmp etc); - test if size is less than 5Mb - save FULL SIZE version to folder "upload/files/" with original name - save THUMBNAIL (max width: 100px; max height: 86px) to folder "upload/thumbnails/" with same original name That's it. I'm mostly interested in the AJAX jQuery script, and the PHP script that will accept and process the files, as I don't know how to do it. Everything else should be pretty simple. No CSS needed. Thanks for your time.