It is an object to improve coding efficiency by suitably setting, with respect to input information in moving image coding, a parameter for quantization calculation at the time of quantization. Various parameters for quantization calculation are set by a parameter setter 103, quantization is performed with the set parameters for quantization calculation by a quantizer 102, a coding cost J is calculated from a generated code amount R and a quantization distortion amount R obtained as a result thereof, and a parameter judgment unit 107 for quantization calculation selects, as a parameter for quantization calculation having highest coding efficiency, a parameter by which the coding cost J becomes minimum.