VARIABLE RESOLUTION MPEG DECODER

摘要

PROBLEM TO BE SOLVED: To make it possible to change a resolution and a pixel size of an output picture with a simple structure without needing low pass filtering processing by selecting a DCT coefficient needed for obtaining a desired frequency characteristics and performing an inverse DCT conversion by using only the selected DCT coefficient. SOLUTION: An inverse DCE conversion means 103 uses a specified DCT coefficient obtained at an inverse quantization means 102 and performs inverse DCT conversion. A motion compensation means 106 performs motion compensation by an image signal inputted from an accumulation means 105 and a motion vector obtained from an inverse Huffman decoding means 101. A switch means 107 switches between an output of the inverse DCT conversion means 103 and the output of an adding means 104 in accordance with frame kinds of I, P or B and outputs an output picture. The DCT coefficient control means 108 selects a desired DCT coefficient in accordance with the demanded resolution of the output picture and controls the DCT coefficient used by the inverse quantization means 102 and the inverse DCT conversion means 103.