  Almost all previous works on saliency detection have been dedicated to
conventional images, however, with the outbreak of panoramic images due to the
rapid development of VR or AR technology, it is becoming more challenging,
meanwhile valuable for extracting salient contents in panoramic images.
  In this paper, we propose a novel bottom-up salient object detection
framework for panoramic images. First, we employ a spatial density estimation
method to roughly extract object proposal regions, with the help of region
growing algorithm. Meanwhile, an eye fixation model is utilized to predict
visually attractive parts in the image from the perspective of the human visual
search mechanism. Then, the previous results are combined by the maxima
normalization to get the coarse saliency map. Finally, a refinement step based
on geodesic distance is utilized for post-processing to derive the final
saliency map.
  To fairly evaluate the performance of the proposed approach, we propose a
high-quality dataset of panoramic images (SalPan). Extensive evaluations
demonstrate the effectiveness of our proposed method on panoramic images and
the superiority of the proposed method against other methods.
