ThemeForest has a nice feature; It allows the authors to upload zip files containing screenshots of their themes. A script then extracts these files and displays the images accordingly. NETTUS has shown us how to open zip files with PHP.

First of all, we create a simple upload form that allows the user to select a zip file. Ensure that the user chooses a zip file, and then save it to as a unique file. And then, extract the contents from the zip file and save them to a specific folder. And finally delete the zip file and echo out the contents.

Source: How to Open Zip Files with PHP