Shane Mayer was fatally stabbed in the leg outside Gabba’s Bar in Forge Street, Darlaston, on July 24, 2019.
The 21-year-old, from Wolverhampton, collapsed in a nearby road following the attack between 11.13pm and 11.14pm and died in hospital three days later.
Expert witness John Kennedy, who was called to give evidence at Birmingham Town Court on Wednesday, has poured over the footage, which features thousands of individual frames.
Mr Kennedy has worked in the field of forensic video and audio analysis since he retired from the police force in 1984.
The court heard he has worked closely with security services on the development of covert image acquisition and analysis in England and Northern Ireland.
He has pioneered forensic procedures “all over the world” assisting the FBI in their development at its Quantico academy in Virginia, USA, as well as working on the inquiry into the Hillsborough disaster and the murder of Jamie Bulger.
“The CCTV has the potential to be the perfect witness,” said Mr Kennedy.
“It has no bias or preconceived ideas and is not subject to influence after the event.”
The court heard that one of the four alleged killers, Kamron Reid, 20, was identified as Profile 2 on the CCTV footage covering Forge Street prior to the incident.
Mr Kennedy, who has prepared a report for the trial, said that footage shown to the jury features 1,981 frames.
Paul Lewis QC, defending Reid said: “You are satisfied that Mr Reid has something in his right hand - his right hand which he appears to pass to his left hand.
“Can you see the transference?” asked Mr Lewis.
“No,” Mr Kennedy said.
“We don’t see with any degree of certainty whether something was passed from the right to left hand.”
The court heard that an object appears from the area of Reid’s trouser pocket.
“He appears to be holding a light coloured object in his hand,” said Mr Lewis.
“Is that consistent in your view of him having a mobile phone?
“Yes, my clear impression is that the actions of Reid are entirely consistent with him having a mobile phone, raising it to his face,” replied Mr Kennedy.
“More consistent with being a phone than of a knife? asked Mr Lewis.
“Yes,” replied Mr Kennedy.
“You agree with Mr Windsor (the Crown’s prosecution expert) that it is impossible to say what it is but it is consistent with being a mobile phone?” asked Mr Lewis?
“Yes,” said Mr Kennedy.
Questioning Mr Kennedy prosecutor Michael Burrows QC said: “You gave drawn jurors attention to other evidence in the frames.
“You told us something dark appears and is a different tone from the (Reid’s) hand.
“There is no reference to that in the report.”
“I don’t discuss every frame in the report,” said Mr Kennedy.
“If you thought it was important, why not refer to it in the report?” asked Mr Burrows.
“I did not say it was important,” replied Mr Kennedy.
“I just drew the jury’s attention to it.”
Mr Burrows said the court was looking at the CCTV imagery through an Infra red camera.
“Kamron Reid was wearing dark clothing wasn’t he?” asked Mr Burrows.
“Yes,” replied Mr Kennedy.
“Blocking infra red light would create a shadow,” said Mr Burrows.
“In certain circumstances, yes,” said Mr Kennedy.
Mr Burrows suggested that the dark object is “simply a shadow” of Reid’s hand.
“No, infra red light is not that intense,” said Mr Kennedy.
“I could not respectfully agree with that.”
Kamron Reid, 20, of Herberts Park Road, Bloxwich; Ramani Sanderson, 20, of Walsham Road, near Peckham, London; Joseph Till, 21, of Summer Street, Willenhall; and Lewis Green, 21, of Heathfield Lane West, Darlaston, all deny murder.
Sanderson also denies possessing a bladed article in a public place. Green has admitted carrying a hammer.
Sanderson is also standing trial accused of assaulting a taxi driver in a separate incident on April 29, 2019.
He is charged with wounding with intent, and possession of a bladed article in a public place. He denies both charges as well.
The trial continues.