A Quantitative Analysis of the Effect of Human Detection and Segmentation Quality in Person Re-identification Performance

Person re-identification, a problem of person identity association across camera views at different locations and times, is the second step in two-steps system for automatic video surveillance: person detection, tracking and person re-identification. However, most of the reported person Re-ID methods deal with the human regions of interest (ROIs) which are extracted manually with well-aligned bounding boxes. They mainly focus on designing discriminative feature descriptors and relevant metric learning on these manually-cropped human ROIs. This paper aims at answering two questions: (1) Do human detection and segmentation affect the performance of person re-identification?; (2) How to overcome the effect of human detection and segmentation with the state of the art method for person re-identification? To answer these two question, quantitative evaluations have been performed for both single-shot and multishot scenarios of person re-identification. Different state-of-the-art methods for human detection and segmentation have been evaluated on two benchmark datasets (VIPeR and PRID2011). The obtained results allow to give some suggestions for developing fully automatic video surveillance systems.