Saliency Enhancement using Superpixel Similarity

Saliency Object Detection (SOD) has several applications in image analysis. Deep-learning-based SOD methods are among the most effective, but they may miss foreground parts with similar colors. To circumvent the problem, we introduce a post-processing method, named \textit{Saliency Enhancement over Superpixel Similarity} (SESS), which executes two operations alternately for saliency completion: object-based superpixel segmentation and superpixel-based saliency estimation. SESS uses an input saliency map to estimate seeds for superpixel delineation and define superpixel queries in foreground and background. A new saliency map results from color similarities between queries and superpixels. The process repeats for a given number of iterations, such that all generated saliency maps are combined into a single one by cellular automata. Finally, post-processed and initial maps are merged using their average values per superpixel. We demonstrate that SESS can consistently and considerably improve the results of three deep-learning-based SOD methods on five image datasets.