"Cunning, ferocious and frightened of nothing on land or in water."

This is how the Top End's crocodiles were described by a British-accented narrator in a black-and-white 1940s Government film unearthed by the National Film and Sound Archive (NFSA).

Directed by prolific Australian director Lee Robinson, the 1949 short documentary depicts both gun-wielding groups and traditional hunters from Daly River's Brinkin tribe pursuing the region's infamous apex predator.

In one scene, three Brinkin men are seen stalking a crocodile's air bubbles from a canoe before launching steel barbed harpoons and jumping into the water to wrestle the dying reptile.

Indigenous hunters stalked crocodiles in canoes with spears and wrestled their prey underwater. ( Supplied: NFSA )

In another scene, a group of non-Indigenous hunters, guided by a man named Donkey, haul a 13-foot specimen into a boat.

"That's the scene that sticks with you the most," NFSA production coordinator Richard Carter told 105.7 ABC Darwin.

"Better them than you."

The 1949 film had been stored in Government archives for decades, but this month the NFSA decided to digitise and upload it online in the lead up to the 30th anniversary of the release of the Australian classic Crocodile Dundee.

Unlike Paul Hogan's weathered Mick Dundee, the crocodile hunters in Robinson's film were a long way from Hollywood and would have spent about six months a year on the job.

"Sometimes it's a lonely life and sometimes dangerous but, for a man with the courage to do battle with the man-eaters, there are rich rewards," the film's narrator said.

For the Brinkin hunters depicted, the pay-off was mostly meat, while the non-Indigenous hunters depict the beginnings of the Northern Territory's now-booming crocodile leather industry.

Non-Indigenous hunters stalked crocodiles for their skins and were often guided by knowledgeable Indigenous tribesmen. ( Supplied: NFSA )

"It's an interesting contrast," Mr Carter said.

"For a film so early, you don't always get that complete picture of what's going on, but in this you get to see all sides."

Mr Carter said the film would have likely been commissioned by the NT Government as part of a broader showcase of industries across Australia, and that it would have aired before feature films at cinemas across the country.

Apart from the rare glimpse at pre-1950s crocodile hunting techniques, Mr Carter said the film was a good example of Robinson's early work.

The director later went on to produce films with actor Chips Rafferty and in 1966 formed a production company with John McCallum to produce the now legendary children's show Skippy The Bush Kangaroo.

"He was a big fan of the outback," Mr Carter said.

Later this month, the NFSA will release other gems relating to the theme of Crocodile Dundee, including unedited footage from the 1986 film and an interview with the man who made Dundee's famous knife.