ENCODING METHOD AND DECODING METHOD

• Main Authors: CHUJOH TAKESHI, TANIZAWA AKIYUKI
• Format: Patent
• Language: English; Korean
• Published: 20.11.2018
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; PICTORIAL COMMUNICATION, e.g. TELEVISION

실시형태에 따른 암호화 방법은 인덱스 설정 단계, 예측 단계, 및 암호화 단계를 포함한다. 인덱스 설정 단계는 참조 화상 및 가중 계수의 정보를 나타내는 인덱스를 설정한다. 예측 단계는 적어도 하나의 참조 화상과 암호화될 대상 화상 간의 화소치 변화가 특정의 기준 이하일 때의 가중 계수의 기준치가 예측치로서 도출되도록 예측을 행한다. 암호화 단계는 상기 가중 계수와 상기 예측치 간의 차분치를 암호화한다. An encoding method, comprising:encoding a first denominator for a luma weighting factor;encoding a first difference value that is equal to a value of a difference between the first denominator and a second denominator for a chroma weighting factor;encoding a second difference value of the luma weighting factor, wherein the second difference value is equal to a value of a difference between the luma weighting factor and a first reference value, and the first reference value is equal to a value obtained by left shift of "1" by at least one binary digit specified by the first denominator;encoding a third difference value of the chroma weighting factor, wherein the third difference value is equal to a value of a difference between the chroma weighting factor and a second reference value, and the second reference value is equal to a value obtained by left shift of "1" by at least one binary digit specified by the second denominator; andencoding a fourth difference value of a chroma offset, wherein the fourth difference value is equal to a value of a difference between the chroma offset and a third reference value, and the third reference value is equal to a value obtained by subtracting a value obtained by both multiplying a median value of a maximum pixel value by the chroma weighting factor and shifting to right for the at least one binary digit specified by the second denominator, from the median value.