A data processing apparatus includes a SNR distribution data generating unit, a filter processing unit, a weighting function generating unit and a corrected data generating unit. The SNR distribution data generating unit generates SNR distribution data of processing target data based on the processing target data. The filter processing unit generates filter processed data obtained by performing filter processing to the processing target data to improve a SNR of the processing target data. The weighting function generating unit generates a weighting function based on the SNR distribution data. The corrected data generating unit generates corrected data by performing weighted calculation between the processing target data and the filter processed data using the weighting function.