From lisby1's photostream on flickr; image made lighter by gogm.
Christie's auctioned this as, "Portrait of Louise de Kerouaille, Duchess of Portsmouth (1649-1734), three-quarter-length, in a red dress with a green cloak, beside an orange tree."
Keywords: Lely, Louise de Kérouaille, Duchess, mistress, Charles II, spy, curly coiffure, chemise, modesty piece, elbow length under-sleeves, cuffs, bodice, scoop neckline, over-sleeves, close skirt, clasps, wrap