In a mandarin tone recognition system, the parameter is usually pitch contour. But the tone can also be partly characterized by pitch difference, energy and energy difference.
普通话声调识别参数除常用的基音轮廓外，基音的一阶差分、能量及能量的一阶差分等也具一定的声调特征。
2
Improves uneven skin tone, reduces yellowish skin and carves out a sharp and beautiful face contour while prevents melanin formation and blocks environmental irritation.