Multi images upload

Hi there, I need to do a function which uploads unlimited number of images at once. The user have the ability to add as many images as he/she wants in one shot. This function should upload the images making two copies of each. One is a resized copy of the original one and the other is the same original size. Also, there are required fields like: title of the image, description and the category that it belongs to. The code should be written in PHP How much this will cost me and how long it takes to be ready? best regards, Hakeem