Review Reports

Round 1

Reviewer 1 Report

The Authors present a cryptanalysis of a 1D chaotic map encryption for color images [9]. The attack is based on a chosen plaintext approach which allows the recovering of the original image.

I think the paper is interesting and well focused, although I have some concerns.

I would suggest the Authors to better explain the previously existing attacks based on chaotic map image encryption. The presented state of the art can be greatly improved by adding a few more up-to-date references since there are only 3 references from the last 5 years. I think Section 3 can be enhance to help the reader through the proposed chosen plaintext attack, especially regarding motivation and contextualization. Why these plaintexts and no others? I would encourage the Authors to provide some numerical results on the computational costs of carrying out the presented attack with respect to, for instance, the encryption itself.

Minor issues:
- Section 2, line 53, "where u and k are initial values". What are u and k? They have not appeared yet nor have been defined.
- Make sure all the used variables have been previously defined.
- Please correct English/notation typos.

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

The paper presents a color image encryption algorithm. The general idea is interesting but the structure of the paper must be improved:

-there is no state of the art

-the paper doesn’t present the novelty of the paper / progress beyond the state of the art

-experiments should be more elaborated (it is not sufficient to evaluate the method with only one image); also it must included compared results with other existing methods: advantages and drawbacks.

-figures must appear in text after they are referred in the text (eg. Figure 1)

-check Figure 3 for a) b), …

 

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

I am satisfied with the enhanced version of the manuscript and answers to my concerns. I thank the Authors for their effort on improving the quality of the article according to Reviewer's suggestions.  

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

The paper was updated according with my comments. Also the results section must be detailed including:

-Results from Figure 3 must be explained more clearly - how was verified that the resulted image is the same as the original one? The evaluation was made only using visual based? it is not clearly if the resulted image is the same.

-Results from table 2 must be interpreted - what is the increasing performance? Both methods were tested on the same computer (or computers with similar resources)?

-In case of Pepper image please explain why the total time is higher that in case of the other two images.

Author Response

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Author Response File: Author Response.docx

Round 3

Reviewer 2 Report

All my comments were addressed. Therefore, in my opinion, the paper can be accepted for publishing.