Patent ID: 6208688
Filing Date: 2001-03-27
Classification: H04N

Abstract:
A method of selecting a requantization step size, comprising:(a) deciding a minimum value of a requantization step size Q2, satisfying 2.multidot.Q1+nint(p.multidot.Q2/q)<2.multidot.Q2 for a quantization step size Q1 of a coded image block of a video image, as quantization step size information;(b) determining a minimum value of a requantization step size Q2, satisfying 4.multidot.Q1+nint(p.multidot.Q2/q)<2.multidot.Q2 for the quantization step size Q1 of the coded image block, as the requantization step size information;(c) taking a minimum value of a requantization step size Q2, satisfying 3.multidot.Q1<2.multidot.Q2 for the quantization step size Q1 of the coded image block, as the requantization step size information; and(d) choosing a minimum value of a requantization step size Q2, satisfying 5.multidot.Q1<2.multidot.Q2 for the quantization step size Q1 of the coded image block, as the requantization step size information, wherein nint(.multidot.) is a nearest integer operator and p and q represent positive integers, respectively.