Method for compressing/decompressing video information

A method for decompressing video information in a video sequence (It, It+1) comprising:

• considering a first video frame (Bt) containing image data;
• segmenting said first video frame (Bt) into segments (St,i);
• for each segment (St,i) of the first video frame (Bt), defining a projected segment (St+1,ip) by applying to the segment (St,i) of the first video frame (Bt), a raw set of motion parameters (Mt,ip) describing the motion between the segment (St,i) of the first video frame (Bt) and the corresponding projected segment (St+1,ip) and
• for each corresponding projected segment (St+1,ip):
• finding in the first video frame (Bt) a corresponding improved segment (St,ib) using both the raw set of motion parameters (Mt,ip) and a motion parameters correction (ΔMt,ip), the corresponding improved segment (St,ib) being the segment of the first video frame (Bt) that would be projected on the corresponding projected segment (St+1,ip) by applying to it the raw set of motion parameters (Mt,ip) corrected by the motion parameters correction (ΔMt,ip);
• and
• defining a corrected projected segment (St+1,ip,o,c) by applying the raw set of motion parameters (Mt,ip) corrected by the motion parameters correction (ΔMt,ip) to the corresponding improved segment (St,ib).

A device for compressing video information in a video sequence (It, It+1) comprising:

• means for segmenting the first video frame (Bt) containing image data into segments (St,i);
• means for searching, in a second video frame (It+1) following the first video frame (Bt) in the video sequence, a corresponding predicted segment (St+1,ip,forward) which matches with the segment (St,i) of the first video frame (Bt) according to a predetermined similarity measure, for each segment (St,i) of the first video frame (Bt);
• means for calculating a raw set of motion parameters (Mt,ip) describing the motion between the segment (St,i) of the first video frame (Bt) and the corresponding predicted segment (St+1,ip,forward) of the second video frame (It+1), for each segment (St,i) of the first video frame (Bt);
• means for searching, in the first video frame (Bt), a corresponding segment (St,ip,backward) that matches with the predicted segment (St+1,ip,forward) of the second video frame (It+1) according to a predetermined similarity measure, for each corresponding predicted segment (St+1,ip,forward) of the second video frame (It+1);
• means for calculating a best set of motion parameters (Mt,ip+ΔMt,ip) describing the motion between the corresponding segment (St,ip,backward) of the first video frame (Bt) and the predicted segment (St+1,ip,forward) of the second video frame (It+1), said best set of motion parameters consisting in the raw set of motion parameters (Mt,ip) corrected by a motion parameter correction (ΔMt,ip), for each corresponding predicted segment (St+1,ip,forward) of the second video frame (It+1).

A device for decompressing video information in a video sequence (It, It+1) comprising:

• means for segmenting said first video frame (Bt) containing image data into segments (St,i);
• means for defining a projected segment (St+1,ip) for each segment (St,i) of the first video frame (Bt), by applying to the segment (St,i) of the first video frame (Bt), a raw set of motion parameters (Mt,ip) describing the motion between the segment (St,i) of the first video frame (Bt) and the corresponding projected segment (St+1,ip);
• means for finding, in the first video frame (Bt), a corresponding improved segment (St,ib) using both the raw set of motion parameters (Mt+1,ip) and a motion parameters correction (ΔMt,ip), the corresponding improved segment (St,ib) being the segment of Bt that would be projected on the corresponding projected segment (St+1,ip) by applying to it the raw set of motion parameters (Mt,ip) corrected by the motion parameters correction (ΔMt,ip), for each corresponding projected segment (St+1,ip);
• and
• means for defining a corrected projected segment (St+1,ip,o,c) by applying the raw set of motion parameters (Mt,ip) corrected by the motion parameters correction (ΔMt,ip) to the corresponding improved segment (St,i b), for each corresponding projected segment (St+1,ip).