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Self-supervised monocular depth estimation has been widely investigated and applied in previous works. However, existing methods suffer from texture-copy, depth drift, and incomplete structure. It is difficult for normal CNN networks to completely understand the relationship between the object and its surrounding environment. Moreover, it is hard to design the depth smoothness loss to balance depth smoothness and sharpness. To address these issues, we propose a coarse-to-fine method with a normalized convolutional block attention module (NCBAM). In the coarse estimation stage, we incorporate the NCBAM into depth and pose networks to overcome the texture-copy and depth drift problems. Then, we use a new network to refine the coarse depth guided by the color image and produce a structure-preserving depth result in the refinement stage. Our method can produce results competitive with state-of-the-art methods. Comprehensive experiments prove the effectiveness of our two-stage method using the NCBAM.


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Self-supervised coarse-to-fine monocular depth estimation using a lightweight attention module

Show Author's information Yuanzhen Li1Fei Luo1( )Chunxia Xiao1( )
School of Computer Science, Wuhan University, Wuhan 430072, China

Abstract

Self-supervised monocular depth estimation has been widely investigated and applied in previous works. However, existing methods suffer from texture-copy, depth drift, and incomplete structure. It is difficult for normal CNN networks to completely understand the relationship between the object and its surrounding environment. Moreover, it is hard to design the depth smoothness loss to balance depth smoothness and sharpness. To address these issues, we propose a coarse-to-fine method with a normalized convolutional block attention module (NCBAM). In the coarse estimation stage, we incorporate the NCBAM into depth and pose networks to overcome the texture-copy and depth drift problems. Then, we use a new network to refine the coarse depth guided by the color image and produce a structure-preserving depth result in the refinement stage. Our method can produce results competitive with state-of-the-art methods. Comprehensive experiments prove the effectiveness of our two-stage method using the NCBAM.

Keywords: monocular depth estimation, texture copy, depth drift, attention module

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Publication history

Received: 07 January 2022
Accepted: 22 February 2022
Published: 16 June 2022
Issue date: December 2022

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© The Author(s) 2022.

Acknowledgements

This work is partially supported by the Key Technological Innovation Projects of Hubei Province (2018AAA062), National Natural Science Foundation of China (61972298), Wuhan University-Huawei GeoInformatics Innovation Lab.

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