In one implementation, a method includes receiving pixel events output by an event sensor that correspond to a feature disposed within a field of view of the event sensor. Each respective pixel event is generated in response to a specific pixel within a pixel array of the event sensor detecting a change in light intensity that exceeds a comparator threshold. A characteristic of the feature is determined at a first time based on the pixel events and a previous characteristic of the feature at a second time that precedes the first time. Movement of the feature relative to the event sensor is tracked over time based on the characteristic and the previous characteristic.