US 6,983,021 B2
Method of encoding a sequence of frames
Beatrice Pesquet-Popescu, Fontenay-Sous-Bois (France); and Vincent Bottreau, Paris (France)
Assigned to Koninklijke Philips Electronics N.V., Eindhoven (Netherlands)
Filed on Apr. 05, 2002, as Appl. No. 10/117,591.
Claims priority of application No. 01400919 (EP), filed on Apr. 10, 2001; and application No. 01400941 (EP), filed on Apr. 12, 2001.
Prior Publication US 2003/0026339 A1, Feb. 06, 2003
Int. Cl. H04N 7/12 (2006.01); H04N 11/02 (2006.01)
U.S. Cl. 375—240.16 4 Claims
 
1. A method for encoding a sequence of frames by means of a three-dimensional (3D) subband decomposition involving a spatial and temporal filtering step applied to the 3D spatio-temporal data which correspond to said sequence of frames considered as a 3D volume, said decomposition being applied to successive groups of frames only after the implementation, on the frames of each group, of block-based motion estimation and compensation operations in the low frequency temporal subbands at each level of the temporal decomposition, and this compensation operation leading, among the filtered pixels, to double-connected pixels corresponding in the current frame to regions of the reference frame becoming uncovered during motion, said method further comprising a decision step based on a minimization criterion and provided for choosing in the current frame, for the temporal filtering of a double-connected pixel of the reference frame, the pixel that leads to a minimum energy of the detail subband, the considered energy being an average energy around said double-connected pixel in the high frequency temporal subband, and said average energy being computed by means of a low-pass filtering operation.