  The ever-growing multimedia traffic has underscored the importance of
effective multimedia codecs. Among them, the up-to-date lossy video coding
standard, Versatile Video Coding (VVC), has been attracting attentions of video
coding community. However, the gain of VVC is achieved at the cost of
significant encoding complexity, which brings the need to realize fast encoder
with comparable Rate Distortion (RD) performance. In this paper, we propose to
optimize the VVC complexity at intra-frame prediction, with a two-stage
framework of deep feature fusion and probability estimation. At the first
stage, we employ the deep convolutional network to extract the spatialtemporal
neighboring coding features. Then we fuse all reference features obtained by
different convolutional kernels to determine an optimal intra coding depth. At
the second stage, we employ a probability-based model and the spatial-temporal
coherence to select the candidate partition modes within the optimal coding
depth. Finally, these selected depths and partitions are executed whilst
unnecessary computations are excluded. Experimental results on standard
database demonstrate the superiority of proposed method, especially for High
Definition (HD) and Ultra-HD (UHD) video sequences.
