Some examples of image preprocessing, including six sets of images showing the comparison between preprocessed images of different shapes of galaxies and the original image. The original image is on the left side of each group of images, in the middle is the image after CAE denoising, and on the right is the image after the polar coordinate unfolding. The data after CAE denoising effectively preserves the characteristics of galaxies while eliminating artifacts such as noise and artifacts in the image. The subsequent APCT processing, after polar coordinate unfolding, inverts the image up and down and concatenates it, enhancing the brightest area in the centre and highlighting the significant differences between different categories of galaxies, thereby enhancing the rotational invariance of the model. From the graph, we can see that galaxies with different morphologies exhibit significant differences after preprocessing.