The photograph showed part of the dealer's hand "and there was potentially a fingerprint," the BBC reported late on Sudnay.
The scientific support unit scanned the image into its system but could not find a match because the photograph contained just parts of the middle and bottom of a finger visible while records only keep the top part.
However, other evidence was enough for the police to guess who was behind the drugs operation.
"While the scale and quality of the photograph proved a challenge, the small bits were enough to prove he was the dealer," Dave Thomas from South Wales Police's scientific support unit was quoted as saying.
"There was the photograph of the hand holding pills that seemed like it was sent to potential customers saying 'these are my wares, I'm selling these'," Thomas said.
"It has now opened the floodgates and when there is part of a hand on a photograph, officers are sending them in," he added.
According to the police officer, the dealers are using the technology not to get caught and the police need to keep up with advancements.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)