A computer-implemented method for predicting a scattered signal of an X-ray for an examination object, the method comprising: scanning each phantom in a scanning manner in which a scattering degree of each phantom in a plurality of phantoms is less than a reference scattering degree, so as to obtain first projection data of each phantom; scanning each phantom in a scanning manner in which the scattering degree of each phantom in the plurality of phantoms is equal to the reference scattering degree, so as to obtain second projection data of each phantom; obtaining a real scattered signal (Sr) of each phantom by subtracting the first projection data of the phantom from the second projection data of the phantom; training a learning model based on the second projection data of each phantom and the real scattered signal (Sr) of each phantom to obtain a trained learning model; and applying the trained learning model to projection data of the X-ray for the examination object to predict the scattered signal in the projection data of the X-ray; wherein the scanning each phantom in a scanning manner in which a scattering degree of each phantom in a plurality of phantoms is less than a reference scattering degree, so as to obtain first projection data of each phantom comprises: performing segmented scanning on each of the plurality of phantoms with a first width less than a reference scanning width under a plurality of different scanning conditions to collect projection data of each first segment of each phantom with the first width under each scanning condition, wherein the reference scanning width is a width used when standard clinical scanning is performed; and obtaining the first projection data of each phantom under each scanning condition by connecting the projection data of each first segment of each phantom collected under each scanning condition; wherein the scanning each phantom in a scanning manner in which the scattering degree of each phantom in the plurality of phantoms is equal to the reference scattering degree, so as to obtain second projection data of each phantom comprises: scanning each of the plurality of phantoms with the reference scanning width under the plurality of different scanning conditions to collect the second projection data of each phantom under each scanning condition. scanning each phantom in a scanning manner in which a scattering degree of each phantom in a plurality of phantoms is less than a reference scattering degree, so as to obtain first projection data of each phantom; scanning each phantom in a scanning manner in which the scattering degree of each phantom in the plurality of phantoms is equal to the reference scattering degree, so as to obtain second projection data of each phantom; obtaining a real scattered signal (Sr) of each phantom by subtracting the first projection data of the phantom from the second projection data of the phantom; training a learning model based on the second projection data of each phantom and the real scattered signal (Sr) of each phantom to obtain a trained learning model; and applying the trained learning model to projection data of the X-ray for the examination object to predict the scattered signal in the projection data of the X-ray; wherein the scanning each phantom in a scanning manner in which a scattering degree of each phantom in a plurality of phantoms is less than a reference scattering degree, so as to obtain first projection data of each phantom comprises: performing segmented scanning on each of the plurality of phantoms with a first width less than a reference scanning width under a plurality of different scanning conditions to collect projection data of each first segment of each phantom with the first width under each scanning condition, wherein the reference scanning width is a width used when standard clinical scanning is performed; and obtaining the first projection data of each phantom under each scanning condition by connecting the projection data of each first segment of each phantom collected under each scanning condition; performing segmented scanning on each of the plurality of phantoms with a first width less than a reference scanning width under a plurality of different scanning conditions to collect projection data of each first segment of each phantom with the first width under each scanning condition, wherein the reference scanning width is a width used when standard clinical scanning is performed; and obtaining the first projection data of each phantom under each scanning condition by connecting the projection data of each first segment of each phantom collected under each scanning condition; wherein the scanning each phantom in a scanning manner in which the scattering degree of each phantom in the plurality of phantoms is equal to the reference scattering degree, so as to obtain second projection data of each phantom comprises: scanning each of the plurality of phantoms with the reference scanning width under the plurality of different scanning conditions to collect the second projection data of each phantom under each scanning condition.