The best photo resizer plugin ?

Hello. I’m in an urgent need of a good wordpress plugin to resize images. I want it to resize images for me and allow me to place the resized images in certain positions.

For example if I upload the photo named picture.jpg to be able to place a 150×150 version of it on the homepage and a 500×200 version inside posts. Basically I want it to call the resize function for certain values I want.