Non-contact camera based methods to measure the pulse rate have been introduced in recent years. However, the previous research conducted experiments only for adults and/or sleeping infants, not for awake infants. In this paper, we compare the principal non-contact camera based methods and identify a suitable method for awake infants. We measured the pulse rate of five adults and three infants and obtained the success rate of setting the measurement region and RMSE of estimated pulse rates for several existing methods. The color based method and is the Independent component analysis are the most suitable methods for setting the measurement region and signal processing, respectively.