  The existing still-static deep learning based saliency researches do not
consider the weighting and highlighting of extracted features from different
layers, all features contribute equally to the final saliency decision-making.
Such methods always evenly detect all "potentially significant regions" and
unable to highlight the key salient object, resulting in detection failure of
dynamic scenes. In this paper, based on the fact that salient areas in videos
are relatively small and concentrated, we propose a \textbf{key salient object
re-augmentation method (KSORA) using top-down semantic knowledge and bottom-up
feature guidance} to improve detection accuracy in video scenes. KSORA includes
two sub-modules (WFE and KOS): WFE processes local salient feature selection
using bottom-up strategy, while KOS ranks each object in global fashion by
top-down statistical knowledge, and chooses the most critical object area for
local enhancement. The proposed KSORA can not only strengthen the saliency
value of the local key salient object but also ensure global saliency
consistency. Results on three benchmark datasets suggest that our model has the
capability of improving the detection accuracy on complex scenes. The
significant performance of KSORA, with a speed of 17FPS on modern GPUs, has
been verified by comparisons with other ten state-of-the-art algorithms.
