Sergent of Voltigeurs 1810
French Army, Napoleonic Wars.
This sergent of Voltigeurs (single gold stripe on the forearm) is wearing the earlier, pre-1812 uniform and would appear to be in campaign dress for the Peninsular War.
He is wearing plumet, cords and flounders and white gloves so presumably the Emperor or a Marshal at least is present, as such a precious item would not normally have been worn in combat.
The yellow and green denotes a Voltigeur, and the bugle horn is the universal symbol for light troop.