Infrared image grayscale data compression method and system

The invention discloses an infrared image grayscale data compression method, which comprises the following steps: firstly, obtaining a temperature value appointed by a user as a high-temperature threshold value and a temperature value appointed by the user as a low-temperature threshold value to determine a temperature interval appointed by the user; determining a gray value interval correspondingto the temperature interval by querying a mapping table, adjusting the gray value greater than the gray value interval in the original gray data to be a unified maximum gray value, and adjusting thegray value smaller than the gray value interval in the original gray data to be a unified minimum gray value; eliminating interference of images outside the temperature interval, and achieving compression of gray scale data. The gray value of the gray value interval is mapped to the interval between the maximum gray value and the minimum gray value, so that the contrast ratio of the image in the temperature interval can be