"Higher Resolution Global Land Cover Mapping"program requires the radiometric normalization of two sets of base-year（ 2000

2010） global coverage 30 m resolution remote sensing data. All data must be converted from Digital Number（ DN） v alues to surface reflectance. Landsat TM / ETM + and HJ-1A / B CCD data are used in this study. A number of these data are not suitable for absolute atmospheric correction. To ensure the global coverage of these data

we have designed an algorithm for automatic relative radiometric normalization and accuracy verification. By using overlapping areas of the adjacent data

the data are converted directly from DN values to surface reflectance by means of relative radiometric correction. The MODIS surface reflectance product（ MOD09GA） is used as reference data

and the relative consistency of the corresponding bands is measured. Image block processing and OpenMP acceleration technologies are used to improve the efficiency of the algorithm. Practical application shows that our algorithm can meet the projected radiometric normalization accuracy

speed

and automation requirements.