Populated urban environments are very important in many applications such as urban planning and entertainment. Techniques that populate a 3D virtual city with hundreds of pedestrians walking in real-time have previously been developed using image based rendering techniques. However, when visualising these avatars nearby the viewpoint, such methods provide a poor rendering quality. In this paper, we propose a method based on three rendering techniques used as levels of details. We provide continuous transitions between them by maintaining a similar dynamic lighting on each level. For closed objects, we use a polygonal representation. At the intermediate level, we adapt the existing layered impostor technique to animated objects and we add a dynamic lighting. As the object gets further, this layered representation is used with a decreasing number of layers to reach the third level, a one-polygon impostor. Our technique contributes to improve the realism of virtual humans in a crowd while maintaining an interactive frame rate.