Coding method for realizing high degree of parallelism rewriting of scalable video bitstream

The invention discloses a coding method for realizing high degree of parallelism rewriting of scalable video bitstream. The method comprises the steps of detecting that whether the decoded image information in a reference queue is used when the motion vector predicted value of a current macro block is obtained when the macro block of a bidirectional prediction piece in the basic layer of a certain access unit is in a Direct or Skip mode; if yes, changing the mode of the current macro block to be a normal prediction mode and computing the motion vector difference of the current macro block under the normal prediction mode; and utilizing the normal prediction mode to perform entropy coding processing on the residual difference information and texture information when the current macro block is in the Direct or Skip mode so as to obtain the bitstream, capable of being rewritten in a parallelism mode, of the current macro block. By the coding method disclosed by the invention, the degree of parallelism and rewriting speed during rewriting are improved, thus meeting the use requirements under the environment with higher real time degree.