In this paper, a non-contact respiratory rate measurement method based on RGB video information is proposed. The method is divided into four steps: first, perform spatial filtering and noise reduction on each frame image of the input video; then use the grayscale compensation algorithm to perform grayscale compensation on the denoised image. Set the magnitude of learning depth, from quantitative analysis and qualitative analysis. From two perspectives, quantitatively analyze the impact ability of the investment index; establish a judgment matrix, determine the weight coefficient of the grading evaluation index system, set the evaluation result consistency index, and test the evaluation results. A hardware interface circuit is designed by using a thermistor to detect the heat of each exhaled gas through a bridge. And the temperature information is transmitted to the receiving device by wireless transmission, and processed by the single chip microcomputer.