AutoLC: Search Lightweight and Top-Performing Architecture for Remote Sensing Image Land-Cover Classification

TL;DR

AutoLC introduces a novel neural architecture search method that efficiently designs lightweight yet high-performing models for high-resolution remote sensing land-cover classification, outperforming existing approaches.

Contribution

The paper proposes a hierarchical search space and a combined encoder-decoder search strategy to automatically generate efficient models tailored for HRS land-cover classification.

Findings

AutoLC achieves superior accuracy on LoveDA dataset.

It reduces computational cost compared to state-of-the-art methods.

AutoLC produces lightweight models suitable for practical deployment.

Abstract

Land-cover classification has long been a hot and difficult challenge in remote sensing community. With massive High-resolution Remote Sensing (HRS) images available, manually and automatically designed Convolutional Neural Networks (CNNs) have already shown their great latent capacity on HRS land-cover classification in recent years. Especially, the former can achieve better performance while the latter is able to generate lightweight architecture. Unfortunately, they both have shortcomings. On the one hand, because manual CNNs are almost proposed for natural image processing, it becomes very redundant and inefficient to process HRS images. On the other hand, nascent Neural Architecture Search (NAS) techniques for dense prediction tasks are mainly based on encoder-decoder architecture, and just focus on the automatic design of the encoder, which makes it still difficult to recover the refined mapping when confronting complicated HRS scenes. To overcome their defects and tackle the HRS land-cover classification problems better, we propose AutoLC which combines the advantages of two methods. First, we devise a hierarchical search space and gain the lightweight encoder underlying gradient-based search strategy. Second, we meticulously design a lightweight but top-performing decoder that is adaptive to the searched encoder of itself. Finally, experimental results on the LoveDA land-cover dataset demonstrate that our AutoLC method outperforms the state-of-art manual and automatic methods with much less computational consumption.