Automatic label generation systems, which are capable to generate huge amounts of labels with limited human efforts, enjoy lots of potential in the deep learning era. These easy-to-come-by labels inevitably bear label noises due to a lack of human supervision and can bias model training to some inferior solutions. However, models can still learn some plausible features, before they start to overfit on noisy patterns. Inspired by this phenomenon, we propose a new Peaks fusion assisted EArly-Stopping (PEAS) approach for imagery segmentation with noisy labels, which is mainly composed of two parts. First, a fitting based early-stopping criterion is used to detect the turning phase from which models are about to mimic noise details. After that, a peaks fusion strategy is applied to select reliable models in the detection zone to generate final fusion results. Here, validation accuracies are utilized as indicators in model selection. The proposed method was evaluated on New York City dataset whose labels were automatically collected by a rule-based label generation system, thus noisy to some extent due to a lack of human supervision. The experimental results showed that the proposed PEAS method can achieve both promising statistical and visual results when trained with noisy labels.

Discovering ancient agricultural terraces in desert regions is important for the monitoring of long-term climate changes on the Earth’s surface. However, traditional ground surveys are both costly and limited in scale. With the increasing accessibility of aerial and satellite data, machine learning techniques bear large potential for the automatic detection and recognition of archaeological landscapes. In this paper, we propose a deep semantic model fusion method for ancient agricultural terrace detection. The input data includes aerial images and LiDAR generated terrain features in the Negev desert. Two deep semantic segmentation models, namely DeepLabv3+ and UNet, with EfficientNet backbone, are trained and fused to provide segmentation maps of ancient terraces and walls. The proposed method won the first prize in the International AI Archaeology Challenge. Codes are available at https://github.com/wangyi111/international-archaeologyai-challenge.