High load image uploader/resizer in conjunction with Amazon S3

we are running a product oriented service, that requires us to daily download and resize thousands and thousands of photos from various web sources and then upload them to Amazon's S3 bucket and use Cloud Front to serve them...

now the proble开发者_开发技巧m is that downloading and resizing is really resource consuming and it would take a lot of hours to process them all...

What we are looking for is a service, that would do this for us fast and of course for a reasonable price...

anybody knows such a service? I tried to google it but don't really know how to form the search to get what I need