A method may include obtaining real-time image data relating to at least one scene acquired by a camera and identifying a plurality of real-time first features relating to a plurality of subjects from the real-time image data. The method may include determining one or more first estimated values corresponding to the plurality of real-time first features, the first estimated values being represented by a first coordinate system. The method may further include obtaining one or more first reference values corresponding to the plurality of real-time first features, the first reference values being represented by a second coordinate system, each of the first estimated values corresponding to one of the first reference values. The method may further include determining one or more real-time target parameters of the camera based on the first estimated values and the first reference values.