The application discloses an open set image classification field self-adaption method based on self-step learning, first, the original image is preprocessed to obtain an image set, then a
feature extraction module and a double multi-class classifier module are constructed and trained to align shared class features of source domain images and target domain images and separate target domain private class features, a multi-criteria cross-domain
hybrid module is further constructed and trained, cross-domain
hybrid images are generated by using the source domain images and the target domain images, and the shared class features are self-learned, and finally, a
classification result of the target domain image is output. Compared with the existing open set image classification field self-adaption method, the application covers smooth and non-smooth class distribution, and does not need to empirically adjust the threshold for distinguishing common class images and private class images in the
inference stage, so that the model has good robustness under different hyperparameters and experimental settings.