Cops are furious about this “joint” operation.

Two “knuckleheads” recorded a brazen prank video in which one of them weighs out marijuana — on the trunk of a marked NYPD patrol car.

“Even if it is a prank, the fact that they feel comfortable doing it there shows that there’s no respect for police,” one cop source said, noting that the pot and scale seen in the clip looked real.

“Are you kidding me?”

Said another police source, “I suspect it’s a couple knuckleheads who are trying to make a video because cops aren’t around.”

The 18-second video shows a man pulling weed from a plastic baggie and placing a cluster of buds on a scale on top of the back of a Brooklyn-based 83rd Precinct cop car.

The unmanned car was parked outside a park in Bushwick, with no sign of the officers assigned to it.

“Yo, you want an eighth?” the man asks, referring to one eighth of an ounce.

“Yeah, I want an eighth, bro,” the cameraman replies.

“That’s three point six for you,” the marijuana handler says, pointing to the nearly 4 grams of weed.

The videographer turns the camera away and says, “Yo, let’s get the f- -k out of here!”

The video was credited to David Jimenez Jr., 29, of Bushwick, who told The Post that he recorded it only “as a joke.”

“I don’t think police should be offended because there was no money exchanged,” he said. “I’m more of a weed activist than a dealer. I was basically giving the weed away.”

“It was just supposed to be a funny joke,” he added. “[But] I could see how people would infer it was a drug deal.”

“I respect police officers, and I respect everything they do for our community,” Jimenez said.

“Someone was killed in the park before, a gang shooting, and everyone had been scared to go in the park, and I just thought that it would lighten up the mood in the area, to be completely honest. I didn’t mean for it to get out.”

But the video was picked up by the Instagram account @NewYorkCityUncut, which says it features the city’s best “pranks, fights and fails.”

The video, shot on July 31 at Bushwick Playground on Knickerbocker Avenue and Madison Street, had racked up more than 6,000 views on Saturday.

A police spokesman said cops were investigating the incident as a possible crime — criminal possession of marijuana.