I got the headers by right-clicking on some image links and seeing what I got. Can't reproduce it right now. Apologies if there was a brain freeze moment.
I've been thinking about how to best do this over the weekend and the approach I cam up with is this: Use Cloudfront (Amazon's CDN) and use custom CNAMES for S3 buckets. An S3 bucket would be an image library (say tango.stdicon.com) and so the subdirectories of this Cloudfront subdomain would be the images sizes (tango.stdicon.com/48/foo).
This sets up a nice CDN with proper headers and a scalable way to add more libraries (just add subdomains).
This also has the "very advanced use-case" advantage: website owners can CNAME to the same library subdomain multiple times (say assets1.mysite.com assets2.mysite.com and assets3.mysite.com) and let the browser download images in parallel. See these two refs:
I've been thinking about how to best do this over the weekend and the approach I cam up with is this: Use Cloudfront (Amazon's CDN) and use custom CNAMES for S3 buckets. An S3 bucket would be an image library (say tango.stdicon.com) and so the subdirectories of this Cloudfront subdomain would be the images sizes (tango.stdicon.com/48/foo).
This sets up a nice CDN with proper headers and a scalable way to add more libraries (just add subdomains).
This also has the "very advanced use-case" advantage: website owners can CNAME to the same library subdomain multiple times (say assets1.mysite.com assets2.mysite.com and assets3.mysite.com) and let the browser download images in parallel. See these two refs:
1. http://www.stevesouders.com/blog/2008/03/20/roundup-on-paral...
2. http://www.websiteoptimization.com/speed/tweak/parallel/
Would love to talk more if you're interested. Email address "encoded" in my profile page.