That horse is about to takeoff. As a showjumping rider, that horse looks very confident and leaning back on his hindquarters ready to jump. Those shields would look like any brightly coloured showjumping fence so to the horse, its just another obstacle. As long as the troops didnt move suddenly or stand up, you woudl be quite safe. Dont forget, horses have a sense of self preservation.
If he didnt want to jump those shields, trust me he would have put the brakes on, a long way away from where he is.
Unfortunately, that rider's position, ie holding the reins so tight that the horse cant lower his head and neck to judge the height, plus sitting back hard in the saddle is doing everything to prevent that horse jumping well, and true, risking the horse not getting his legs high enough or body for that matter.
Would have been interesting to see the rest of the jumping sequence to see just how much the horse actually cleared the top of those shields. My money is, it would have been quite low, if not touching a shield as his hind legs dragged over.
Here endeth the "how to showjump" lesson. Great shot though!
D D