An explosion of cellphone videos has brought renewed attention to police practices, provoking criticism, indictments and talk of criminal justice overhaul. Courtroom videos of judges in action, however, are far rarer.

But one surreptitious video in a small-town Georgia court has led to an overhaul of court practices there. The video showed the judge threatening to jail traffic violators who could not come up with an immediate payment toward their fines.

“You can pay what you have, you can call whoever you need to call, go to an A.T.M. if you need to, do what you need to do,” Judge Richard A. Diment of Bowdon Municipal Court said to one defendant. “Call friends, call family, call your employer. But until you get $300 here tonight, you won’t be able to leave.” The defendant said she had recently begun working at a supermarket and had $150 with her.

To another defendant, a man who said he had been unemployed for two years and received food stamps, Judge Diment said: “You’re going to have to figure out a way to get this paid, do you understand me? Or you’re going to go to jail. One or the other. You understand?”