The automatic segmentation and classification of skin lesions are two essential tasks in computer-aided skin cancer diagnosis. Segmentation aims to detect the location and boundary of the skin lesion area, while classification is used to evaluate the type of skin lesion. The location and contour information of lesions provided by segmentation is essential for the classification of skin lesions, while the skin disease classification helps generate target localization maps to assist the segmentation task. Although the segmentation and classification are studied independently in most cases, we find meaningful information can be explored using the correlation of dermatological segmentation and classification tasks, especially when the sample data are insufficient. In this paper, we propose a collaborative learning deep convolutional neural networks (CL-DCNN) model based on the teacher–student learning method for dermatological segmentation and classification. To generate high-quality pseudo-labels, we provide a self-training method. The segmentation network is selectively retrained through classification network screening pseudo-labels. Specially, we obtain high-quality pseudo-labels for the segmentation network by providing a reliability measure method. We also employ class activation maps to improve the location ability of the segmentation network. Furthermore, we provide the lesion contour information by using the lesion segmentation masks to improve the recognition ability of the classification network. Experiments are carried on the ISIC 2017 and ISIC Archive datasets. The CL-DCNN model achieved a Jaccard of 79.1% on the skin lesion segmentation task and an average AUC of 93.7% on the skin disease classification task, which is superior to the advanced skin lesion segmentation methods and classification methods.

Training a generalized reliable model is a great challenge since sufficiently labeled data are unavailable in some open application scenarios. Few-shot learning (FSL) aims to learn new problems with only a few examples that can tackle this problem and attract extensive attention. This paper proposes a novel few-shot learning method based on double pooling squeeze and excitation attention (dSE) for the purpose of improving the discriminative ability of the model by proposing a novel feature expression. Specifically, the proposed dSE module adopts two types of pooling to emphasize features responding to foreground object channels. We employed both the pixel descriptor and channel descriptor to capture locally identifiable channel features and pixel features of an image (as opposed to traditional few-shot learning methods). Additionally, in order to improve the robustness of the model, we designed a new loss function. To verify the performance of the method, a large number of experiments were performed on multiple standard few-shot image benchmark datasets, showing that our framework can outperform several existing approaches. Moreover, we performed extensive experiments on three more challenging fine-grained few-shot datasets, the experimental results demonstrate that the proposed method achieves state-of-the-art performances. In particular, this work achieves 92.36% accuracy under the 5-way–5-shot classification setting of the Stanford Cars dataset.