1. A method for generating a triggering signal for a pedestrian protection device in which sensor data are ascertained and analyzed, the method comprising: analyzing the sensor data for ascertaining an object mass and an object hardness; and generating, after a collision with an object has been recognized, features from the sensor data, the triggering signal for the pedestrian protection device if the ascertained object mass and the ascertained object hardness are within, a triggering range which represents a collision with a pedestrian, wherein the sensor data include acceleration information, wherein the object hardness is ascertained by determining a frequency from a period of the acceleration information; and, wherein the object hardness is derived from an integral of the absolute values of the acceleration information, the calculated integral being a measure of the object hardness and the integral being greater for higher frequencies of the vibrations.