title: Lossless crop n drop (cut and paste) for JPEGs
body: <p>I'm looking for examples/blog posts/etc of lossless jpeg operations (crop n drop = cut and paste). I know there is a program <code>jpegtran</code> (http://jpegclub.org/jpegtran) which can perform lossless cropping (in certain situations), but there seems to be a lack of good documentation.   Yes, I have tried the google.</p>
  
  <p><code>jpegtran</code> also has an experimental branch that allows lossless dropping (= pasting) in certain situations, but the documentation of this seems to be even worse.</p>
  
  <p>What about jpegtran's <code>drop</code> switch is experimental? Does it have known issues? Do people use it?</p>
  
  <p><code>drop</code> seems like a really cool and useful feature, and I find it odd that it's been experimental for over 10 years...</p>
  
  <p>And yes, one could use lossless formats such as PNG for such operations, but I'm specifically interested in JPEGs.</p>
  
  <p>Thanks!</p>