This Stack Overflow question, which was originally ambiguous, has been clarified, and the intent is clearly to try to try to capture the frames of a video, presumably to make his own copy of it.
This sort of question could have dubious legal/moral applications, e.g. to capture copyrighted materials. (Admittedly, there could be legitimate reasons for it, too, but it strikes me that if the provider of the content wanted to provide a download feature, they would have.) For this reason, now that the intent is a little more clear, I have elected to remove my comments and my answer, as I personally don't want to help someone write an app that does this. Clearly, that's my personal choice and I'm not seeking feedback on that decision.
My question is this: Is it appropriate to flag a question for moderator attention on these grounds? The question is not explicitly asking something illegal, for example, "how do I make my own copies of copyrighted materials," but the answer could certainly be used for unscrupulous reasons. What is the appropriate action/answer for a question like this?
I see these sorts of issues occasionally. The other example I've seen periodically is, effectively, "how do I track a user's location without telling them". But that seems easier, as I can make my point and still provide a constructive answer (e.g. point out the approved methods and bring their attention to the relevant app store guideline that prohibits the unapproved behavior).
But this "can you help me with techniques that copy frames from a video" is more ambiguous.