Was James Files captured on camera?

This picture shows a figure walking behind the retaining wall in front of the Texas School Book Depository. He appears to be wearing a hat and he looks to be walking towards the Daltex building. His elbow looks to be in an angle, consistent with someoone who has his hand in his jacket-pocket. The other arm seems to be stretched along the body as if he is carrying something.

“I know that after I had put the Fireball away, I know I had a Colt 45 inside my pocket on the left side of me…my briefcase was in right hand and I was prepared to shoot my way out of there if it came down to that…. I did not look back over my shoulder…I did not run…I did not stand around…I just carried a natural gait and proceeded to exit….just like a business man walking away from lunch.”

And here is a fragment of the Nix film at the time of the shots. It appears there is movement behind the picket fence on the grassy knoll. This could well be the head of James Files.

Is this a puff of smoke coming from the picket fence?