Motion estimation method using adaptive mode decision
A motion estimation method using adaptive mode decision is disclosed. The method includes a motion vector difference value calculation step of calculating a motion vector difference value using an input motion vector estimation value x component for a current block and an input x offset corresponding to a current SAD. At the MVD Variable Length Coding (VLC) step, the length of a bit string, which is obtained by performing variable-length coding on an MVDx, is calculated. At a motion vector difference value calculation step, a motion vector difference value is calculated using an input motion vector estimation value y component for a current block and an input y offset corresponding to the current SAD. At an MVD VLC step, the length of a bit string, which is obtained by performing variable-length coding on an MVDy, is calculated. Thereafter, the amount of motion vector coding is produced by adding the MVDx and the MVDy. The amount of texture coding of a current block or a macro block is estimated using SAD values and quantization coefficients of previous macro blocks. A SAD correction coefficient is produced using the amount of motion vector coding and the texture vector coding amount. Finally, the SAD values are multiplied by the SAD correction coefficient, thus correcting the SAD values.
1. A motion estimation method using adaptive mode decision to remove temporal redundancy in moving picture compression, comprising:
a motion vector difference value calculation step of calculating a motion vector difference value using an input motion vector estimation value x component for a current block and an input x offset corresponding to a current Sum of Absolute Difference (SAD), and outputting a Motion Vector Difference x (MVDx) as a result of the calculation;
an MVD Variable Length Coding (VLC) step of calculating a length of a bit string that is obtained by performing variable-length coding on the MVDx, and outputting an MVDx coding length as a result of the calculation;
a motion vector difference value calculation step of calculating a motion vector difference value using an input motion vector estimation value y component for a current block and an input y offset corresponding to the current SAD, and outputting a Motion Vector Difference y (MVDy) as a result of the calculation;
an MVD VLC step of calculating the length of a bit string that is obtained by performing variable-length coding on the MVDy, and outputting an MVDy coding length as a result of the calculation;
a step of producing an amount of motion vector coding by adding the MVDx and the MVDy;
a step of estimating an amount of texture coding of a current block or a macro block using SAD values and quantization coefficients of previous macro blocks;
a step of producing a SAD correction coefficient using the amount of motion vector coding and the texture vector coding amount; and
a step of multiplying the SAD values by the SAD correction coefficient;
wherein the SAD values are corrected.
2. The motion estimation method set forth in claim 1 , wherein the generation of the SAD value is performed by controlling weight, which prefers macro block-based motion estimation, using the amount of motion vector coding and the amount of texture vector coding;
wherein a motion vector, in which a sum of the amount of texture coding and the amount of the motion vector coding, is minimized is found.