Radiometric Compensation for Occluded Crops Imaged Using High-Spatial-Resolution Unmanned Aerial Vehicle System

Round 1

Reviewer 1 Report

Abstract: Numerical results of the accuracy analysis need to be presented.

 

Line 76: the word “modeling” is repeated twice?

 

Line 78 states a third  approach, while line 72 states there are two approaches?

 

 

Lines 79-80: This is very important statement. It needs to be supported by a reference.

 

 

Line 82: But authors said  “thresholding approach” has disadvantages in lines 72-75, 79-80? 

 

Objectives need to be stated more clearly.

 

Line 97: Names what irrigation systems are used?

 

Line 98: List these crops.

 

Figure in line 100 has no number, no caption, and it is not referred to in the manuscript. Moreover, What is the large black spot in the top middle of the figure? Is it a shadow? How this large spot of shadow was created?

 

Section 2.4: More clear technical description is needed on how georeferencing was done. Moreover, make clear connection between georeferencing and image stretching.

 

Provide description of each parameter used in each equation.

 

Not clear what software was/were used in this study?

 

Figure 5, Figure 8, Figure 9 and Figure 11. Add to the caption the labels of the letters used in the figure.

 

The major drawback of this study is the lack of validation of the obtained results.

At least minor English check is needed

Author Response

Please see the attachment

Reviewer 2 Report

The authors proposed a simple and reliable approach for compensating radiometric distortions in crops under total occlusion using brightness-based compensation and thresholding methods. However, there is a need for significant revisions in terms of the presentation, experiments, and rewriting certain sections.

1-      The first paragraph of the introduction and abstract is same, which is not correct way to present. Please paraphrase this.

 

2-      In the introduction, it is important to clearly define radiometric distortions and their impact on crop mapping using UAV (Unmanned Aerial Vehicle) images. The authors can begin by highlighting the undesired effects of radiometric errors in multispectral remote sensing UAV images, caused by factors such as atmospheric conditions, variations in solar radiation, sensor viewing angles, and sensor calibration errors. They can provide references [x], [xx] and [xxx] to support these statements. Subsequently, specific radiometric errors commonly encountered in UAV images, such as shadows, can be discussed, which motivates the authors to propose a shadow compensation approach. The introduction should conclude by addressing the effects of these errors on crop mapping and estimation.

 

[x] https://doi.org/10.1080/01431168608948958

[xx] https://doi.org/10.1080/01431161.2022.2102951

[xxx] https://doi.org/10.1016/j.measurement.2015.08.003

 

3-      In the final part of the introduction, it is essential to provide a clear explanation of the novelties introduced in the study and address the limitations of existing works. The authors can highlight the unique contributions of their approach, such as the utilization of brightness-based compensation and thresholding methods for radiometric compensation in crops under total occlusion. They can emphasize how their method differs from previous approaches and offers improved accuracy and reliability in compensating radiometric distortions.

Additionally, the authors should address the limitations of existing works in radiometric compensation for crops. They can discuss the challenges faced by previous methods, such as the inability to effectively handle total occlusion scenarios and the lack of simplicity and reliability in the compensation process. By clearly articulating the novelties of their approach and addressing the limitations of existing works, the authors can highlight the significance and value of their research.

4-      In the materials and methods section, it is important to accurately cite the relevant references for each formula presented. Correct citation enhances the credibility and clarity of the methodology.

 

5-      Providing a workflow or flowchart for the presented work would greatly assist in understanding the methodology. It would allow readers to follow the step-by-step process of the proposed approach, which is currently difficult to comprehend.

 

6-      It is crucial to explicitly discuss the limitations of the presented work and provide possible solutions for future research. Identifying the shortcomings of the proposed approach and suggesting potential avenues for improvement will enhance the quality and impact of the study.

 

 

 

 

 

 

1-      I strongly recommend that the manuscript undergo thorough proofreading to rectify any potential grammar errors and ensure the cohesiveness and coherence of the text. It is crucial to present the research findings in a clear and organized manner, and a comprehensive proofreading process will help achieve this goal. By addressing any grammatical inconsistencies or discontinuities in the manuscript, the authors can enhance the overall quality and readability of their work.

Author Response

Please see the attachment

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The paper discusses an important topic. However, lack of ground truthing data for validation makes it difficult to support obtained results.

Reviewer 2 Report

The authors have satisfactorily addressed most of my concerns.