CLEVELAND -

Prosecutors in Ohio released a frame-by-frame analysis of the surveillance camera footage first made public a year ago that shows a white Cleveland police officer fatally shooting a black 12-year-old boy who had a pellet gun.

The additional images taken from surveillance video at a recreation center where Tamir Rice was shot and killed don't appear to contain any new or substantive information. The new footage was released in the "spirit of openness," said Cuyahoga County Prosecutor Tim McGinty.

The analysis also doesn't show whether Tamir, as police officials have maintained, was reaching into his waistband for the pellet gun when then-rookie patrolman Timothy Loehmann shot him less than two seconds after getting out of the car.

The enhancement by a video expert will be presented to a grand jury that will decide if Loehmann or his field-training officer should be charged criminally for Tamir's death. Loehmann shot Tamir outside Cudell Recreation Center on Nov. 22, 2014.

Saturday's release of the enhancement comes the same day that attorneys for the boy's family asked the prosecutor to allow their use-of-force experts to testify before the grand jury. The request follows the release of reports by use-of-force experts hired by prosecutors that concluded the shooting was justified because the officers had no way of knowing that Tamir's pellet gun wasn't a real firearm.

Loehmann and patrolman Frank Garmback were sent to a Cleveland recreation center after a man called 9-1-1 to report that a man was waving a gun and pointing it at people. The caller told the dispatcher that the gun might not be real. The call also said the man might be a juvenile, but that information wasn't passed on to the officers.