Method and apparatus for predicting frequency transform coefficients in video codec, video encoder and decoder having the apparatus, and encoding and decoding method using the method

• Main Author: KIM SO-YOUNG,PARK JEONG-HOON,LEE SANG-RAE,PARK SEUNG-RAN,SOHN YU-MI
• Format: Patent
• Language: English
• Published: 26.07.2006
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; PICTORIAL COMMUNICATION, e.g. TELEVISION

Provided are a method and apparatus for predicting frequency transform coefficients in a video codec, a video encoder and decoder having the apparatus, and an encoding and decoding method using the method. The method of predicting the frequency transform coefficients in a frequency transform domain includes: calculating a cost between a DC coefficient of a current frequency transformed block that is to be predicted and DC coefficients of frequency transformed blocks adjacent in horizontal, vertical, and diagonal directions with respect to the current frequency transformed block; and selecting an adjacent block with the smallest calculated cost, and predicting DC and AC coefficients of the current frequency transformed block using coefficients of the selected adjacent block. Accordingly, compression efficiency can be improved, and video data can be effectively encoded reflecting the characteristics of various patterns by calculating prediction values of numerous patterns.