Inverse transforming method and device for transform scanning table in video decoding

The present invention relates to the field of multimedia video technology, and discloses an AVS inter-frame forecasting pixel generating device, including a main state controller, a dual-port FIFO, a data cache register pile, a brightness forecasting pixel generating unit, chrominance forecasting pixel generating unit and a weighting forecasting unit. The device integrates a dual-port memory, can simultaneously read data, store the input predicted data and calculate 1/4 or 1/8 accuracy forecasting pixel; 1/4 pixel accuracy forecast adopts a three-stage flowing water structure, 1/8 pixel accuracy forecast adopts a two-stage flowing water structure; each clock period produces a forecast pixel generating result; the adoption of the three-stage flowing water pixel generating structure improves the performance frequency; and a three-stage multiplexed filtering unit is adopted to calculate 1/4 pixel forecast. The inter-frame forecast pixel generating structure and method, which has high-performance performance and smaller area, is applied to 1/4 accuracy and 1/8 accuracy inter-frame forecast pixel generating process in other video standards.