VIDEO SCALABLE ENCODING METHOD AND DECODING METHOD AND APPARATUSES THEREFOR

摘要

A video scalable encoding method calculates a weight coefficient which includes a proportional coefficient and an offset coefficient and indicates brightness variation between an encoding target image region and a reference image region in an upper layer, calculates a motion vector by applying the weight coefficient to an image signal of a reference image region as a search target and executing motion estimation, and generates a prediction signal by applying the weight coefficient to a decoded -signal of a reference image region indicated by the motion vector and executing motion compensation. Based on encoding information of an immediately-lower image region in an immediately-lower layer, which is present at spatially the same position as the encoding target image region, a data structure of the weight coefficient is determined. When the immediately-lower image region performed interframe prediction in the immediately-lower layer, the method identifies an immediately-lower layer reference image region that the immediately-lower image region used as a prediction reference for motion prediction, and calculates the weight coefficient by applying a weight coefficient that the immediately-lower image region used in weighted motion prediction to a DC component of an image region in the upper layer, which is present at spatially the same position as the immediately-lower layer reference image region, and assuming a result of the application as a DC component of the immediately-lower image region.