Crop and Resize Images Plugin allows you to easily modify WordPress uploaded images.

Allows you to use Timthumb easy and regenerate your thumbnails after changing the thumbnail sizes.

Automatically optimizes responsive images for each visitor's screen using Pixtulate's servers and delivers them worldwide over CDN.

This plugin resize the image which is already uploaded and it is updating image at run time

Manually Crop and Resize thumbnail images that are uploaded in the Media section.

WPImager is an image editor you can use to create visual content for your blog.