  Traditional intra prediction usually utilizes the nearest reference line to
generate the predicted block when considering strong spatial correlation.
However, this kind of single line-based method does not always work well due to
at least two issues. One is the incoherence caused by the signal noise or the
texture of other object, where this texture deviates from the inherent texture
of the current block. The other reason is that the nearest reference line
usually has worse reconstruction quality in block-based video coding. Due to
these two issues, this paper proposes an efficient multiple line-based intra
prediction scheme to improve coding efficiency. Besides the nearest reference
line, further reference lines are also utilized. The further reference lines
with relatively higher quality can provide potential better prediction. At the
same time, the residue compensation is introduced to calibrate the prediction
of boundary regions in a block when we utilize further reference lines. To
speed up the encoding process, this paper designs several fast algorithms.
Experimental results show that, compared with HM-16.9, the proposed fast search
method achieves 2.0% bit saving on average and up to 3.7%, with increasing the
encoding time by 112%.
