IMAGE ENCODER, IMAGE DECODER, IMAGE ENCODING PROGRAM, AND IMAGE DECODING PROGRAM

摘要

PROBLEM TO BE SOLVED: To improve the accuracy of the predicted value of quantization parameters.SOLUTION: Provided is an image encoder for performing frequency conversion and quantization on each divided block of an image by using quantization parameters, the encoder comprising: a selection unit for selecting an encoded block in an image including blocks to be processed which have been subjected to inter-image prediction and a similar block resembling the encoded block in a reference image referenced by a motion vector for the blocks to be processed by considering the motion of the encoded block; and a prediction unit for adding, to quantization parameters for a block to be referenced by the motion vector for the blocks to be processed, a difference value between quantization parameters for the encoded block and similar block selected by the selection unit and defining the added value as a prediction value of quantization parameters for the blocks to be processed.