AWS storage is cheap as chips, unlike a lot of their other services which can really mount up. We moved tens of thousands of images from one server to AWS using the AWS CLI. Simply pointed it to the images we wanted to move, the full contents of the directory in this case, pointed it to the AWS Bucket we had set-up, and hit enter. Took a few minutes to transfer the entire directory contents. A simpler option is to do it locally (example link on how to do this here, but there are many guides available on this subject), so download the images to your local machine, this avoids some issues with various hosts and permissions/security/firewall rules/policies etc. We then used a simple Cloud Formation script on AWS to carry out the re-sizing of images on the fly, video here which will guide you through, and explain, the process and what is going on…
Advantages of this is that storage is very cheap. No need for complex operations in re-sizing images, and you can maintain the integrity of the original image. The use of the script is free, and the processing doesn’t cost a penny.