A video decoding method includes receiving video data and transforming the video data from a Huffman tree to at least one full tree and at least one one-side tree. One microcode corresponding to the video coding standard that has encoded the received video data is read where a format of the read microcode is determined. The method further includes reading video data from the transformed video data according to the consuming length of the read microcode if the format of the read microcode is a leaf, and decoding the read video data according to the decoding field of the read microcode to output a decoding result.