Based on a simple HVAC climate model, considered the effect of latitude, distributing of land and water, terrain and discrepancy on town and village, ascertained the parameter.

The spectrum-character-curve method is mainly based on spectrum similarity;and the waters spectrum curve is taken as the central criterion;when spectrum curve of target pixel accords with the criterion,the target pixel is classified to waters,otherwise,it belongs to land,so two-value segmenting of waters and land is realized.