Non-concept density estimation via kernel regression for concept ranking in weakly labelled data
Automatic object annotation for weakly labelled images/videos has attracted great research interests. In the literature, the idea of negative mining has been proposed for the task. Following existing works, the authors start with image/video over-segmentation. With the assumption that the noisy segments in the concept images and the strongly labelled non-concept segments are drawn from the same distribution, the authors plan to estimate the non-concept distribution and apply it to the ambiguous segments to generate a concept ranking. Although this idea was proposed in existing work and was shown ineffective when combined with a naive kernel density estimation strategy, in this study, the authors explore improved density estimation techniques for the ranking and propose a kernel regression model whose parameters are estimated by a maximum likelihood estimation. Experimental results validate the effectiveness of their method.