1. An apparatus for estimating a location of a mobile body and generating a map of a mobile body environment using an upper image of the mobile body environment, the apparatus comprising: a landmark generating unit to observe corner points from the upper image obtained by photographing in an upper vertical direction in the mobile body environment and to respectively generate landmarks from the observed corner points; and a location and map operation unit to estimate the location of the mobile body and to generate the map of the mobile body environment from the landmarks, wherein the landmark generating unit selects one or more landmarks and one or more landmark candidates that belong to a previous upper image, among previously registered landmarks and landmark candidates, predicts locations of the selected landmarks and the selected landmark candidates in a current upper image, and searches for corner points that have been used to respectively generate landmarks or landmark candidates that belong to the previous upper image, among the observed corner points by using coordinates of the corner points that have been observed at the current upper image and local feature descriptors that classify the corner points, and registers the landmark candidate that has been observed as the corner point more than a predetermined number of times among the landmark candidates as a landmark, wherein the landmark candidate is distinguished from the corner point, the landmark and the landmark candidate, wherein the landmark candidate is registered among the corner points that have not been used to generate both the landmark and the landmark candidate in the previous upper image by using the predicted locations of the selected landmarks and the selected landmark candidates, wherein the corner point is registered as the landmark candidate when a distance from the corner point to the landmark or the landmark candidate is greater than a first predetermined distance or when a distance from the local feature descriptor of the corner point and the local feature descriptor of the landmark or the landmark candidate is greater than a second predetermined distance, and wherein the current upper image is an upper image that has been obtained currently and the previous upper image is an upper image that has been obtained previously.