Abstract: Several methods and a system to perform determination of a field referencing pattern are disclosed. In one aspect, a method is disclosed. A motion vector of a previously coded frame is analyzed using a processor and a memory. A statistic is updated based on whether the motion vector includes one or more of a fractional pel vertical component, a half pel vertical component, and an integer pel vertical component. A field referencing pattern of a target field is determined based on the statistic and an exception protocol.

Abstract: This invention enables determination of the best video encoding mode for a macroblock in the SKIP mode and comparing this cost with other modes. This invention avoids sub-pixel interpolations for fractional pixels. This invention models the cost function in a quadratic model and computes the cost for a nearest integer pel and plural adjacent integer pels. This permits determination of the coefficients of the quadratic model. An estimated cost is obtained using the actual fractional pel position in the quadratic model. This method can be used for obtaining the cost of a P Skip mode. This method can be used for the decision of B direct or B skip modes in B frames.