Abstract

The deep-learning-network performance depends on the accuracy of the training samples. The training samples are commonly labeled by human visual investigation or inherited from historical land-cover or land-use maps, which usually contain label noise, depending on subjective knowledge and the time of the historical map. Helping the network to distinguish noisy labels during the training process is a prerequisite for applying the model for training across time and locations. This study proposes an antinoise framework, the Weight Loss Network (WLN), to achieve this goal. The WLN contains three main parts: (1) the segmentation subnetwork, which any state-of-the-art segmentation network can replace; (2) the attention subnetwork (λ); and (3) the class-balance coefficient (α). Four types of label noise (an insufficient label, redundant label, missing label and incorrect label) were simulated by dilate and erode processing to test the network’s antinoise ability. The segmentation task was set to extract buildings from the Inria Aerial Image Labeling Dataset, which includes Austin, Chicago, Kitsap County, Western Tyrol and Vienna. The network’s performance was evaluated by comparing it with the original U-Net model by adding noisy training samples with different noise rates and noise levels. The result shows that the proposed antinoise framework (WLN) can maintain high accuracy, while the accuracy of the U-Net model dropped. Specifically, after adding 50% of dilated-label samples at noise level 3, the U-Net model’s accuracy dropped by 12.7% for OA, 20.7% for the Mean Intersection over Union (MIOU) and 13.8% for Kappa scores. By contrast, the accuracy of the WLN dropped by 0.2% for OA, 0.3% for the MIOU and 0.8% for Kappa scores. For eroded-label samples at the same level, the accuracy of the U-Net model dropped by 8.4% for OA, 24.2% for the MIOU and 43.3% for Kappa scores, while the accuracy of the WLN dropped by 4.5% for OA, 4.7% for the MIOU and 0.5% for Kappa scores. This result shows that the antinoise framework proposed in this paper can help current segmentation models to avoid the impact of noisy training labels and has the potential to be trained by a larger remote sensing image set regardless of the inner label error.

Highlights

  • With the ability to unify features at different image levels, deep-learning networks have achieved great success in the remote sensing field

  • With a noise rate of 50%, the accuracy of U-Net drops significantly, and at noise level 2, OA decreases by 4.4%, Mean Intersection over Union (MIOU) by 7.7%, and Kappa by 2.0%; at noise level 3, OA decreases by 12.7%, MIOU by 20.7%, and Kappa by 13.8%

  • Weight Loss Network (WLN) can still maintain high accuracy even when the noise rate increases; with a noise rate of 50%, OA decreases by 1.2%, MIOU decreases by 2.1%, and

Read more

Summary

Introduction

With the ability to unify features at different image levels, deep-learning networks have achieved great success in the remote sensing field. A deep-learning network’s performance mainly depends on (1) the size and variety of the training data and (2) the accuracy of the training labels. Compared to the former factor, errors in training labels are usually hard to identify and correct. Unlike the nature-image dataset in the computer-science field, noisy labels are more likely to occur in remote-sensed image. The main reasons are that the land-cover and land-use type characteristics may vary depending on different times, locations and sensors. The historic land-cover/land-use maps are usually used in automatic-labeling processing. Designing a framework to intensify deep-learning networks to reduce the impact of these erroneous samples is a much greater challenge

Results
Discussion
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call