The invention provides an AVS intra-frame prediction mode fast
selection algorithm, and the process of the fast
selection algorithm is shown in the attached figure. According to the AVS intra-frame prediction mode fast
selection algorithm, the correlation of optimal
modes of adjacent blocks and the
directivity of brightness variations in the blocks are utilized for mode anticipation so as to shrink the range of candidate
modes; the number of the candidate
modes of brightness blocks is reduced to three at most from original five; an optimal intra-frame prediction mode is selected for one
macro block, and calculation of
rate distortion cost J of the brightness blocks needs to be conducted for 20 times in optimized
reference software rm52j-new. By means of the AVS intra-frame prediction mode fast selection
algorithm, the calculation needs to be conducted for 12 times at the maximum and only 8 times at the minimum; compared with an rm52j-new
algorithm, the average brightness
signal to
noise ratio of the fast selection
algorithm is reduced to be less than 0.09dB, the
code rate is increased to be less than 1.52%, and total coding time can be saved by 17.3%-29.5%; moreover, the anticipation of the modes by the fast selection algorithm is completely based on the characteristics of an image, and therefore effects can be guaranteed when the fast selection algorithm is applied to different sequences.