Nottinghamshire Police are looking for the men who hospitalised a 23-year-old man with a serious head injury.
The assault happened on Saturday 12 March at around 2.30am in Cranbrook Street near the city centre.
Nottinghamshire Police believe the men do not know the victim of the attack.
Detective Constable Chris Underwood said: “The intention of releasing this footage is to show the very violent nature of this unprovoked assault in hopes of appealing to someone’s conscience.
“As you can see, one of the men repeatedly stamps on the victim’s head, a man who we believe is a stranger to him.
“With such ferocious blows aimed at his head, this could easily have been a murder inquiry. If you recognise anyone in this footage please give a call on 101.”
If you know anyone in this footage contact us on 101 or call Crimestoppers anonymously on 0800 555 111.