  With the progress of Mars exploration, numerous Mars image data are collected
and need to be analyzed. However, due to the imbalance and distortion of
Martian data, the performance of existing computer vision models is
unsatisfactory. In this paper, we introduce a semi-supervised framework for
machine vision on Mars and try to resolve two specific tasks: classification
and segmentation. Contrastive learning is a powerful representation learning
technique. However, there is too much information overlap between Martian data
samples, leading to a contradiction between contrastive learning and Martian
data. Our key idea is to reconcile this contradiction with the help of
annotations and further take advantage of unlabeled data to improve
performance. For classification, we propose to ignore inner-class pairs on
labeled data as well as neglect negative pairs on unlabeled data, forming
supervised inter-class contrastive learning and unsupervised similarity
learning. For segmentation, we extend supervised inter-class contrastive
learning into an element-wise mode and use online pseudo labels for supervision
on unlabeled areas. Experimental results show that our learning strategies can
improve the classification and segmentation models by a large margin and
outperform state-of-the-art approaches.
