A method for extracting only a portion stained with a specific dye from a pathology slide stained with a mixed dye in which various types of dyes are mixed, training an artificial neural network, and determining a pathology image stained by using various staining techniques; and a computing system performing same. A neural network learning system generates and learns a learning data set including M pieces of individual learning data (where M is a natural number greater than or equal to 2).