Extracting Fractional Vegetation Cover from Digital Photographs: A Comparison of In Situ, SamplePoint, and Image Classification Methods
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area
2.2. Field Experiment Design
2.3. Image Analysis
3. Results and Discussion
3.1. Comparison of SamplePoint Estimation and In Situ Assessment
3.2. Comparison of Image Analysis Methods and In Situ Assessments
3.3. Differences between In Situ Assessment, Visual Classification with SamplePoint Software, and Image Classification Methods
4. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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SamplePoint | Unsupervised Classification | Supervised Classification | OBIA | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
PV | NPV | BS | PV | NPV | BS | PV | NPV | BS | PV | NPV | BS | |
Mean (%) | 0.45 | −0.37 | −0.52 | −4.39 | −9.22 | 14.06 | −2.64 | −5.36 | 8.08 | 1.31 | −2.75 | 1.75 |
SD (%) | 8.76 | 12.90 | 11.78 | 15.35 | 16.83 | 17.92 | 8.22 | 11.70 | 11.65 | 7.59 | 9.41 | 8.72 |
Mean ± 1.96SD | −16.7 ~ +17.6 | −25.7 ~ +24.9 | −23.6 ~ +22.6 | −34.5 ~ +25.7 | −42.2 ~ +23.8 | −21.1 ~ +49.2 | −18.8 ~ +13.5 | −28.3 ~ +17.6 | −14.8 ~ +30.9 | −13.6 ~ +16.2 | −21.2 ~ +15.7 | −15.3 ~ +18.8 |
Mean ± 3SD | −25.8 ~ +26.7 | −39.1 ~ +38.3 | −35.9 ~ +34.8 | −50.4 ~ +41.7 | −59.7 ~ +44.5 | −39.7 ~ +67.8 | −27.3 ~ +22.0 | −40.5 ~ +29.7 | −26.9 ~ +43.0 | −21.5 ~ +24.1 | −31.0 ~ +25.5 | −24.4 ~ +27.9 |
SamplePoint 1 | Unsupervised Classification 2 | Supervised Classification 2 | OBIA 2 | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
PV | NPV | BS | PV | NPV | BS | PV | NPV | BS | PV | NPV | BS | |
p-value (%) | 0.25 | 0.33 | 0.071 | 0.11 | 0.003 * | 0.0002 * | 0.08 | 0.10 | 0.0005 * | 0.17 | 0.06 | 0.089 |
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Yu, X.; Guo, X. Extracting Fractional Vegetation Cover from Digital Photographs: A Comparison of In Situ, SamplePoint, and Image Classification Methods. Sensors 2021, 21, 7310. https://doi.org/10.3390/s21217310
Yu X, Guo X. Extracting Fractional Vegetation Cover from Digital Photographs: A Comparison of In Situ, SamplePoint, and Image Classification Methods. Sensors. 2021; 21(21):7310. https://doi.org/10.3390/s21217310
Chicago/Turabian StyleYu, Xiaolei, and Xulin Guo. 2021. "Extracting Fractional Vegetation Cover from Digital Photographs: A Comparison of In Situ, SamplePoint, and Image Classification Methods" Sensors 21, no. 21: 7310. https://doi.org/10.3390/s21217310
APA StyleYu, X., & Guo, X. (2021). Extracting Fractional Vegetation Cover from Digital Photographs: A Comparison of In Situ, SamplePoint, and Image Classification Methods. Sensors, 21(21), 7310. https://doi.org/10.3390/s21217310