Apparatus and method of adaptively coding/decoding interlaced shape information

摘要

An apparatus and method of adaptively coding/decoding interlace shape information estimates the amount of motion with respect to the binary alpha block (BAB). A type of the BAB is determined according to the estimated amount of motion. When the BAB falls under a type which needs coding, differences between pixel pairs in each line pair comprising an odd and an adjacent even line are calculated and summed up to compute an error of the frame. Differences between pixel pairs in consecutive odd line pairs and differences between pixel pairs in consecutive even line pairs are calculated and summed up to compute an error of individual fields. When the error of the frame is larger than that of the separate fields, field type coding where coding is independently performed with respect to each field is selected. When the error of the separate fields is larger than that of the frame, frame type coding where coding is performed with respect to the frame is selected.