Plugin to Automatically resize original uploaded image?

When uploading a large image I would like the original image to be automatically resized to a width of let’s say 500px. I use a lot of photos thumbnails linked to the original images, so it’s rather annoying to go through each one to find out the medium size image link for each photo.

I tried using the resize feature in the library but it doesn’t resize the original photo but instead creates a new one and – again – it’s annoying to do this for every photo.

Thank you!