Methods, apparatuses, systems, and storage mediums for correcting distortion of a spectrally encoded endoscopy (SEE) image are provided. A first reference pattern comprising a plurality of radial lines is scanned with an SEE spectral line to obtain a first image. Signs of a tangential shift and/or of a radial shift of the spectral line may be determined, and magnitudes of the tangential shift and of the radial shift may be computed. A second reference pattern comprising at least a circle with the SEE spectral line may be scanned to obtain a second image in a case where the radial shift is positive. The magnitude of the radial shift may be computed based on the magnitude of the tangential shift and a radius of the circle. The tangential shift and the radial shift may then be applied for correcting distortion.