Advancing Sika deer detection and distance estimation through comprehensive camera calibration and distortion analysis

IF 5.8 2区环境科学与生态学 Q1 ECOLOGY Ecological Informatics Pub Date : 2025-02-14 DOI:10.1016/j.ecoinf.2025.103064

Sandhya Sharma , Stefan Baar , Bishnu P. Gautam , Shinya Watanabe , Satoshi Kondo , Kazuhiko Sato

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引用次数: 0

Abstract

Commercial camera traps are widely used in global wildlife monitoring, but their effectiveness is often compromised by oversights in specifications and technical considerations. This study evaluates the performance of three camera trap models, including the Solar Powered 4K-trail, HC-801A-Pro and HC-801A, by analysing their resolution limits and lens distortion correction capabilities. To determine the resolution limits, A4-sized templates with red circles of varying diameters were placed within the cameras’ field of view at various distances, with measurements taken using a measuring tape and verified with GPS. Using the cv2.TM_CCOEFF_NORMED template matching algorithm with templates scaled from 0.01 to 2.0 and a confidence threshold of 0.6, the resolution threshold was defined as the distance at which the observed circle size deviated from the expected size. Among the models, the Solar Powered 4K Trail camera had the highest resolution threshold at 17.29 m, while the HC 801A had the lowest at 15.3 m. Lens distortion coefficients were derived by analysing checkerboard pattern images taken at different distances and angles. All three camera models exhibited lens distortion. The Solar Powered 4K-trail and HC-801A-Pro exhibited barrel distortion, while the HC-801A exhibited pincushion distortion. The calculated coefficients successfully corrected these distortions, improving image accuracy. The derived coefficients effectively corrected these distortions, improving image accuracy. This practical and reproducible calibration method, which does not require expensive optical equipment, offers significant improvements in camera trap optimisation, enabling conservationists and researchers to obtain more reliable ecological data.

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来源期刊

Ecological Informatics 环境科学-生态学

CiteScore

8.30

自引率

11.80%

发文量

346

审稿时长

46 days

期刊介绍： The journal Ecological Informatics is devoted to the publication of high quality, peer-reviewed articles on all aspects of computational ecology, data science and biogeography. The scope of the journal takes into account the data-intensive nature of ecology, the growing capacity of information technology to access, harness and leverage complex data as well as the critical need for informing sustainable management in view of global environmental and climate change. The nature of the journal is interdisciplinary at the crossover between ecology and informatics. It focuses on novel concepts and techniques for image- and genome-based monitoring and interpretation, sensor- and multimedia-based data acquisition, internet-based data archiving and sharing, data assimilation, modelling and prediction of ecological data.