A large number of visual data were obtained by a set of observers assessing colour-differences of sample pairs presented under 16 groups of parameters with grey-scale method.
由一组观察者采用灰标法判断以16组不同参数显示的色样对的色差，获取了大量的观察数据。
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He has found that their brains remodel to use variations in pitch, tone and volume - in the same way sighted people use differences in light and colour - to build up a picture of their surroundings.