CODED VIDEO CUT DETECTING METHOD

摘要

PROBLEM TO BE SOLVED: To correctly detect a cut at high speed even in the case of a coded video mixing intra-picture and inter-picture coded frames by estimating a block, where the cut can exist, and discriminating the presence/absence of cut in the inter-picture coded frame included in that block. SOLUTION: The DC component of a DCT coefficient is extracted from an I picture It for each block and defined as it (x, y) (S100). Next, the difference dt (x, y)=it (x, y)-it-1 (x, y) from a DC component it-1 (x, y) of a preceding I picture It-1 is calculated (S101) and a number Dt of picture elements, for which an absolute value|dt (x, y)|of difference is larger than a threshold value T1 , is counted (S102). Then, the number Dt of picture elements is compared with a threshold value T2 (S103). When the number Dt is larger than the threshold value, it is judged the possibility of cut existence between It and It-1 is high, and a subroutine Pro (b) is called (S104). In the other case, 'cut absence' is discriminated and when it is not the final frame of video (S106), processing is moved to the step 100.