Curve data compression method and device based on envelope line

The invention provides a curve data compression method and device based on an envelope line, and relates to the technical field of data compression, and the method comprises the steps: carrying out the spline interpolation based on a local maximum value point in to-be-compressed curve data, and obtaining an upper peak value envelope line and a lower peak value envelope line; based on a preset difference threshold value, respectively identifying curve feature points and non-curve feature points in the upper and lower peak envelope curves, and obtaining an upper envelope feature curve and a lower envelope feature curve; based on a difference algorithm, respectively obtaining a feature segment of the upper envelope feature curve and a feature segment of the lower envelope feature curve; based on a region extreme value method, respectively extracting optimal feature points from data points of the curve data to be compressed corresponding to the feature segments of the upper and lower envelope feature curves; and