Camouflage

@article{barbour1911concealing,
    author = "Barbour, Thomas and Phillips, John C.",
    title = "Concealing Coloration Again",
    year = "1911",
    journal = "The Auk",
    url = "https://doi.org/10.2307/4071434",
    doi = "10.2307/4071434",
    number = "2",
    pages = "179-188",
    volume = "28"
}

@article{crossref1911concealing,
    title = "Concealing Coloration",
    year = "1911",
    journal = "The Auk",
    url = "https://doi.org/10.2307/4071537",
    doi = "10.2307/4071537",
    number = "1",
    pages = "146-148",
    volume = "28"
}

In this book, he says: "The doctrine of concealing coloration as an explanation of almost every kind of coloration in the animal kingdom has received its widest application....In its extreme form as stated by these gentlemen, the doctrine seems to me to be pushed to such a fantastic extreme and to include such wild absurdities as to call for the application of common sense thereto.The Messrs. Thayer state their position in the most positive form.Fundamentally it is that, in the first place, all or practically all animals are concealingly colored, and in the next place, that while their patterns in all cases help thus to conceal them the chief factor in their concealment is the countergradation of shades, their inconspicuousness being due, not to their color being like that of the surrounding objects, but to this countergradation causing them to escape being seen at all.In order to

@article{doi1023074071167,
    author = "Allen, J. A.",
    title = "Roosevelt's 'Revealing and Concealing Coloration in Birds and Mammals'",
    year = "1911",
    journal = "The Auk",
    abstract = {In this book, he says: "The doctrine of concealing coloration as an explanation of almost every kind of coloration in the animal kingdom has received its widest application....In its extreme form as stated by these gentlemen, the doctrine seems to me to be pushed to such a fantastic extreme and to include such wild absurdities as to call for the application of common sense thereto.The Messrs. Thayer state their position in the most positive form.Fundamentally it is that, in the first place, all or practically all animals are concealingly colored, and in the next place, that while their patterns in all cases help thus to conceal them the chief factor in their concealment is the countergradation of shades, their inconspicuousness being due, not to their color being like that of the surrounding objects, but to this countergradation causing them to escape being seen at all.In order to},
    url = "https://doi.org/10.2307/4071167",
    doi = "10.2307/4071167",
    openalex = "W2006843254"
}

Concealing Coloration in Birds and Mammals'!makes an attack on the work of Messrs.

@article{doi1023074071782,
    author = "Allen, Francis H.",
    title = "Remarks on the Case of Roosevelt vs. Thayer, with a Few Independent Suggestions on the Concealing Coloration Question",
    year = "1912",
    journal = "The Auk",
    abstract = "Concealing Coloration in Birds and Mammals'!makes an attack on the work of Messrs.",
    url = "https://doi.org/10.2307/4071782",
    doi = "10.2307/4071782",
    openalex = "W2314655709"
}

@article{bement1917camouflage,
    author = "Bement, Alon",
    title = "Camouflage",
    year = "1917",
    journal = "Teachers College Record: The Voice of Scholarship in Education",
    url = "https://doi.org/10.1177/016146811701800501",
    doi = "10.1177/016146811701800501",
    number = "5",
    pages = "1-3",
    volume = "18"
}

@book{benson1933concealing1,
    author = "Benson, S. B",
    title = "Concealing coloration among some desert rodents of the southwestern United States",
    year = "1933",
    publisher = "University of California Publications in Zoology, v. 40, p. 1-70",
    note = "talkorigins\_source = {true}; raw\_reference = {Benson, S. B., 1933, Concealing coloration among some desert rodents of the southwestern United States: University of California Publications in Zoology, v. 40, p. 1-70.}"
}

@article{cornes1937attitude,
    author = "CORNES, J. J. S.",
    title = "Attitude and Concealing Coloration",
    year = "1937",
    journal = "Nature",
    url = "https://doi.org/10.1038/140684a0",
    doi = "10.1038/140684a0",
    number = "3546",
    pages = "684-684",
    volume = "140"
}

@inproceedings{denton1972the2,
    author = "Denton, E. J. and Nicol, J. A. C. and Gilpin-Brown, J. B. and Wright, P. G",
    title = "The angular distribution of the light produced by some mesopelagic fish in relation to their camouflage",
    year = "1972",
    booktitle = "Proceedings of the Royal Society, London B, v. 182, p. 145-158",
    note = "talkorigins\_source = {true}; raw\_reference = {Denton, E. J., Nicol, J. A. C., Gilpin-Brown, J. B., and Wright, P. G., 1972, The angular distribution of the light produced by some mesopelagic fish in relation to their camouflage: Proceedings of the Royal Society, London B, v. 182, p. 145-158.}"
}

Assessment of camouflage, concealment, and deception (CCD) methodologies is not a trivial problem; conventionally the only method has been to carry out field trials, which are both expensive and subject to the vagaries of the weather. In recent years computing power has increased, such that there are now many research programs using synthetic environments for CCD assessments. Such an approach is at- tractive; the user has complete control over the environment parameters and many more scenarios can be investigated. The UK Ministry of De- fence is currently developing a synthetic scene generation tool for as- sessing the effectiveness of air vehicle camouflage schemes. The soft- ware is sufficiently flexible to allow it to be used in a broader range of applications, including full CCD assessment. The synthetic scene simu- lation system (CAMEO-SIM) has been developed, as an extensible sys- tem, to provide imagery within the 0.4 to 14 mm spectral band with as high a physical fidelity as possible. It consists of a scene design tool, an image generator, that incorporates both radiosity and ray-tracing pro- cesses, and an experimental trials tool. The scene design tool allows the user to develop a three-dimensional representation of the scenario of interest from a fixed viewpoint. Target(s) of interest can be placed any- where within this 3-D representation and may be either static or moving. Different illumination conditions and effects of the atmosphere can be modeled together with directional reflectance effects. The user has com- plete control over the level of fidelity of the final image. The output from the rendering tool is a sequence of radiance maps, which may be used by sensor models or for experimental trials in which observers carry out target acquisition tasks. The software also maintains an audit trail of all data selected to generate a particular image, both in terms of material properties used and the rendering options chosen. A range of verification tests has shown that the software computes the correct values for ana- lytically tractable scenarios. Validation tests using simple scenes have also been undertaken. More complex validation tests using observer tri- als are planned. The current version of CAMEO-SIM and how its images are used for camouflage assessment is described. The verification and validation tests undertaken are discussed. In addition, example images will be used to demonstrate the significance of different effects, such as spectral rendering and shadows. Planned developments of CAMEO-SIM are also outlined. © 2001 Society of Photo-Optical Instrumentation Engineers.

@article{doi10111711390298,
    author = "Gilmore, Marilyn A.",
    title = "CAMEO-SIM: a physics-based broadband scene simulation tool for assessment of camouflage, concealment, and deception methodologies",
    year = "2001",
    journal = "Optical Engineering",
    abstract = "Assessment of camouflage, concealment, and deception (CCD) methodologies is not a trivial problem; conventionally the only method has been to carry out field trials, which are both expensive and subject to the vagaries of the weather. In recent years computing power has increased, such that there are now many research programs using synthetic environments for CCD assessments. Such an approach is at- tractive; the user has complete control over the environment parameters and many more scenarios can be investigated. The UK Ministry of De- fence is currently developing a synthetic scene generation tool for as- sessing the effectiveness of air vehicle camouflage schemes. The soft- ware is sufficiently flexible to allow it to be used in a broader range of applications, including full CCD assessment. The synthetic scene simu- lation system (CAMEO-SIM) has been developed, as an extensible sys- tem, to provide imagery within the 0.4 to 14 mm spectral band with as high a physical fidelity as possible. It consists of a scene design tool, an image generator, that incorporates both radiosity and ray-tracing pro- cesses, and an experimental trials tool. The scene design tool allows the user to develop a three-dimensional representation of the scenario of interest from a fixed viewpoint. Target(s) of interest can be placed any- where within this 3-D representation and may be either static or moving. Different illumination conditions and effects of the atmosphere can be modeled together with directional reflectance effects. The user has com- plete control over the level of fidelity of the final image. The output from the rendering tool is a sequence of radiance maps, which may be used by sensor models or for experimental trials in which observers carry out target acquisition tasks. The software also maintains an audit trail of all data selected to generate a particular image, both in terms of material properties used and the rendering options chosen. A range of verification tests has shown that the software computes the correct values for ana- lytically tractable scenarios. Validation tests using simple scenes have also been undertaken. More complex validation tests using observer tri- als are planned. The current version of CAMEO-SIM and how its images are used for camouflage assessment is described. The verification and validation tests undertaken are discussed. In addition, example images will be used to demonstrate the significance of different effects, such as spectral rendering and shadows. Planned developments of CAMEO-SIM are also outlined. © 2001 Society of Photo-Optical Instrumentation Engineers.",
    url = "https://doi.org/10.1117/1.1390298",
    doi = "10.1117/1.1390298",
    openalex = "W2013478137"
}

@incollection{bährlerapp2007camouflage,
    author = "Bährle-Rapp, Marina",
    title = "Camouflage",
    year = "2007",
    booktitle = "Springer Lexikon Kosmetik und Körperpflege",
    url = "https://doi.org/10.1007/978-3-540-71095-0\_1584",
    doi = "10.1007/978-3-540-71095-0\_1584",
    pages = "86-86"
}

We present a new method to derive a multiscale urban camouflage pattern from a given set of background image samples. We applied this method to design a camouflage pattern for a given (semi-arid) urban environment. We performed a human visual search experiment and a computational evaluation study to assess the effectiveness of this multiscale camouflage pattern relative to the performance of 10 other (multiscale, disruptive and monotonous) patterns that were also designed for deployment in the same operating theater. The results show that the pattern combines the overall lowest detection probability with an average mean search time. We also show that a frequency-tuned saliency metric predicts human observer performance to an appreciable extent. This computational metric can therefore be incorporated in the design process to optimize the effectiveness of camouflage patterns derived from a set of background samples.

@article{doi1011171oe524041103,
    author = "Toet, Alexander and Hogervorst, Maarten A.",
    title = "Urban camouflage assessment through visual search and computational saliency",
    year = "2012",
    journal = "Optical Engineering",
    abstract = "We present a new method to derive a multiscale urban camouflage pattern from a given set of background image samples. We applied this method to design a camouflage pattern for a given (semi-arid) urban environment. We performed a human visual search experiment and a computational evaluation study to assess the effectiveness of this multiscale camouflage pattern relative to the performance of 10 other (multiscale, disruptive and monotonous) patterns that were also designed for deployment in the same operating theater. The results show that the pattern combines the overall lowest detection probability with an average mean search time. We also show that a frequency-tuned saliency metric predicts human observer performance to an appreciable extent. This computational metric can therefore be incorporated in the design process to optimize the effectiveness of camouflage patterns derived from a set of background samples.",
    url = "https://doi.org/10.1117/1.oe.52.4.041103",
    doi = "10.1117/1.oe.52.4.041103",
    openalex = "W2102640070",
    references = "doi10100797894009383355, doi101016jneunet200610001, doi101016s0042698901002504, doi10110934730558, doi101109cvpr20095206596, doi1011678732, doi1023071437762, doi107551mitpress75030030073, openalexw2139047169, openalexw85152245"
}

@misc{diamond2013concealing,
    author = "Diamond, Judy and Bond, Alan B.",
    title = "Concealing Coloration in Animals",
    year = "2013",
    url = "https://doi.org/10.4159/harvard.9780674074200",
    doi = "10.4159/harvard.9780674074200"
}

A spatial color-mixing model based on tricolor angular frequencies is proposed in consideration that the design theory falls behind the application of digital camouflage pattern. The model is based on Fourier transform and Gaussian low-pass filter (LPF). In the model, the tricolor angular frequencies are introduced to the spatial frequency response function of human color vision, and the effects of atmospheric attenuation and air screen brightness on color mixture are considered. The field test shows that the model can simulate the color-mixing process in the aspects of color-mixing order, and shape and position of color-mixing spot. But the color-mixing spot color is not perfect, which can be improved by optimizing the atmospheric parameters and tricolor cut-off angular frequencies. The model provides a tool for the research on digital camouflage pattern.

@article{doi101016jdt201309015,
    author = "Zhang, Yong and Shi-qiang, Xue and Jiang, Xiaojun and Mu, Jing-yang and Yang, Yi",
    title = "The Spatial Color Mixing Model of Digital Camouflage Pattern",
    year = "2013",
    journal = "Defence Technology",
    abstract = "A spatial color-mixing model based on tricolor angular frequencies is proposed in consideration that the design theory falls behind the application of digital camouflage pattern. The model is based on Fourier transform and Gaussian low-pass filter (LPF). In the model, the tricolor angular frequencies are introduced to the spatial frequency response function of human color vision, and the effects of atmospheric attenuation and air screen brightness on color mixture are considered. The field test shows that the model can simulate the color-mixing process in the aspects of color-mixing order, and shape and position of color-mixing spot. But the color-mixing spot color is not perfect, which can be improved by optimizing the atmospheric parameters and tricolor cut-off angular frequencies. The model provides a tool for the research on digital camouflage pattern.",
    url = "https://doi.org/10.1016/j.dt.2013.09.015",
    doi = "10.1016/j.dt.2013.09.015",
    openalex = "W1500261488"
}

Camouflage is perhaps the most widespread anti-predator defense in nature, with many different types thought to exist. Of these, resembling the general color and pattern of the background (background matching) is likely to be the most common. Background matching can be achieved by adaptation of individual appearance to different habitats or substrates, behavioral choice, and color change. Although the ability to change coloration for camouflage over a period of hours or days is likely to be widely found among animals, few studies have quantified this against different backgrounds. Here, we test whether juvenile shore crabs (Carcinus maenas) are capable of color change for camouflage by placing them on either black or white (experiment 1) or red and green (experiment 2) backgrounds. We find that crabs are capable of significant changes in brightness, becoming lighter on white backgrounds and darker on black backgrounds. Using models of predator (avian) vision, we show that these differences are large enough in many individuals to lead to perceptible changes in appearance. Furthermore, comparisons of crabs with the backgrounds show that changes are likely to lead to significant improvements in camouflage and potentially reduced detection probabilities. Crabs underwent some changes on the red and green backgrounds, but visual modeling indicated that these changes were very small and unlikely to be detectable. Our experiment shows that crabs are able to adjust their camouflage by changes in brightness over a period of hours, and that this could influence detection probability by predators.

@article{doi103389fevo201400014,
    author = "Stevens, Martin and Lown, Alice E. and Wood, Louisa E.",
    title = "Color change and camouflage in juvenile shore crabs Carcinus maenas",
    year = "2014",
    journal = "Frontiers in Ecology and Evolution",
    abstract = "Camouflage is perhaps the most widespread anti-predator defense in nature, with many different types thought to exist. Of these, resembling the general color and pattern of the background (background matching) is likely to be the most common. Background matching can be achieved by adaptation of individual appearance to different habitats or substrates, behavioral choice, and color change. Although the ability to change coloration for camouflage over a period of hours or days is likely to be widely found among animals, few studies have quantified this against different backgrounds. Here, we test whether juvenile shore crabs (Carcinus maenas) are capable of color change for camouflage by placing them on either black or white (experiment 1) or red and green (experiment 2) backgrounds. We find that crabs are capable of significant changes in brightness, becoming lighter on white backgrounds and darker on black backgrounds. Using models of predator (avian) vision, we show that these differences are large enough in many individuals to lead to perceptible changes in appearance. Furthermore, comparisons of crabs with the backgrounds show that changes are likely to lead to significant improvements in camouflage and potentially reduced detection probabilities. Crabs underwent some changes on the red and green backgrounds, but visual modeling indicated that these changes were very small and unlikely to be detectable. Our experiment shows that crabs are able to adjust their camouflage by changes in brightness over a period of hours, and that this could influence detection probability by predators.",
    url = "https://doi.org/10.3389/fevo.2014.00014",
    doi = "10.3389/fevo.2014.00014",
    openalex = "W1984049103",
    references = "doi101098rstb20080211, doi101371journalpone0087153"
}

Abstract Camouflage is ubiquitous in the natural world and benefits both predators and prey. Amongst the range of concealment strategies, disruptive coloration is thought to visually fragment an animal’s’ outline, thereby reducing its rate of discovery. Here, I propose two non-mutually exclusive hypotheses for how disruptive camouflage functions, and describe the visual mechanisms that might underlie them. (1) The local edge disruption hypothesis states that camouflage is achieved by breaking up edge information. (2) The global feature disruption hypothesis states camouflage is achieved by breaking up the characteristic features of an animal (e.g., overall shape or facial features). Research clearly shows that putatively disruptive edge markings do increase concealment; however, few tests have been undertaken to determine whether this survival advantage is attributable to the distortion of features, so the global feature disruption hypothesis is under studied. In this review the evidence for global feature disruption is evaluated. Further, I address if object recognition processing provides a feasible mechanism for animals’ features to influence concealment. This review concludes that additional studies are needed to test if disruptive camouflage operates through the global feature disruption and proposes future research directions.

@article{doi101093czoolo614708,
    author = "Webster, Richard",
    title = "Does disruptive camouflage conceal edges and features?",
    year = "2015",
    journal = "Current Zoology",
    abstract = "Abstract Camouflage is ubiquitous in the natural world and benefits both predators and prey. Amongst the range of concealment strategies, disruptive coloration is thought to visually fragment an animal’s’ outline, thereby reducing its rate of discovery. Here, I propose two non-mutually exclusive hypotheses for how disruptive camouflage functions, and describe the visual mechanisms that might underlie them. (1) The local edge disruption hypothesis states that camouflage is achieved by breaking up edge information. (2) The global feature disruption hypothesis states camouflage is achieved by breaking up the characteristic features of an animal (e.g., overall shape or facial features). Research clearly shows that putatively disruptive edge markings do increase concealment; however, few tests have been undertaken to determine whether this survival advantage is attributable to the distortion of features, so the global feature disruption hypothesis is under studied. In this review the evidence for global feature disruption is evaluated. Further, I address if object recognition processing provides a feasible mechanism for animals’ features to influence concealment. This review concludes that additional studies are needed to test if disruptive camouflage operates through the global feature disruption and proposes future research directions.",
    url = "https://doi.org/10.1093/czoolo/61.4.708",
    doi = "10.1093/czoolo/61.4.708",
    openalex = "W2471864214",
    references = "doi101371journalpone0087153"
}

Abstract The assessment of military camouflage is a key consideration in the modern military field. Traditionally, the assessment relies on traditional human visual detection tests because a large scale multi‐level and multi‐factor experiments are time‐ and resource‐consuming. One aspect of camouflage assessment, to which this current study pertains, entails improving upon or “enhancing” an existing or “selected” design. The current study presents a new and practical approach for enhancing the selected military camouflage by utilizing response surface methodology (RSM) of % L *, % a *, and % b * in CIELAB color space. Ten participants were recruited to evaluate 35 variations of % L *, % a *, and % b * on camouflage similarity index (CSI) and reaction time (RT). Based on RSM, the optimum combination occurs at L *: 61.4966, a *: −5.6505, and b *: 10.5114. In addition, a predictive algorithm to calculate the optimum shift of % L *, % a *, and % b * from the original camouflage to the improved camouflage derived from RSM is also proposed. The optimum shift occurs at −25% L *, −55% a *, and + 80% b *. In the end, a new design guideline is proposed for the enhancement of selected military camouflage, which adopts the present study's research findings.

@article{doi101002col22352,
    author = "Lin, Chiuhsiang Joe and Prasetyo, Yogi Tri and Siswanto, Nio Dolly and Jiang, Bernard C.",
    title = "Optimization of color design for military camouflage in CIELAB color space",
    year = "2019",
    journal = "Color Research \& Application",
    abstract = "Abstract The assessment of military camouflage is a key consideration in the modern military field. Traditionally, the assessment relies on traditional human visual detection tests because a large scale multi‐level and multi‐factor experiments are time‐ and resource‐consuming. One aspect of camouflage assessment, to which this current study pertains, entails improving upon or “enhancing” an existing or “selected” design. The current study presents a new and practical approach for enhancing the selected military camouflage by utilizing response surface methodology (RSM) of \% L *, \% a *, and \% b * in CIELAB color space. Ten participants were recruited to evaluate 35 variations of \% L *, \% a *, and \% b * on camouflage similarity index (CSI) and reaction time (RT). Based on RSM, the optimum combination occurs at L *: 61.4966, a *: −5.6505, and b *: 10.5114. In addition, a predictive algorithm to calculate the optimum shift of \% L *, \% a *, and \% b * from the original camouflage to the improved camouflage derived from RSM is also proposed. The optimum shift occurs at −25\% L *, −55\% a *, and + 80\% b *. In the end, a new design guideline is proposed for the enhancement of selected military camouflage, which adopts the present study's research findings.",
    url = "https://doi.org/10.1002/col.22352",
    doi = "10.1002/col.22352",
    openalex = "W2912615365"
}

Abstract Enhancing an existing military camouflage is an important component during the assessment of military camouflage. The current study proposed a new and practical approach to enhancing the undetectability of a military camouflage using particle swarm optimization (PSO). Eight different locations (20 × 50 pixels) in the one swamp background were selected to be the place of a human‐shaped target. The PSO would generate newly proposed camouflage as an empirical parameter based on the lower and the upper bounds from selected four different colors in swamp background. The predictive algorithm was applied to adjust the optimum shift of % L *, % a *, and % b * from the original to the empirical parameter. Thirty participants were recruited to evaluate the original and newly proposed camouflages. Paired sample t test indicates that the newly proposed military camouflage had a significant lower camouflage similarity index value and a longer detection time. The PSO shows to be a method with good results; however, a comprehensive study using multiple backgrounds and patterns would be required to generalize the methodology to other background environments or camouflage patterns.

@article{doi101002col22404,
    author = "Lin, Chiuhsiang Joe and Prasetyo, Yogi Tri",
    title = "A metaheuristic‐based approach to optimizing color design for military camouflage using particle swarm optimization",
    year = "2019",
    journal = "Color Research \& Application",
    abstract = "Abstract Enhancing an existing military camouflage is an important component during the assessment of military camouflage. The current study proposed a new and practical approach to enhancing the undetectability of a military camouflage using particle swarm optimization (PSO). Eight different locations (20 × 50 pixels) in the one swamp background were selected to be the place of a human‐shaped target. The PSO would generate newly proposed camouflage as an empirical parameter based on the lower and the upper bounds from selected four different colors in swamp background. The predictive algorithm was applied to adjust the optimum shift of \% L *, \% a *, and \% b * from the original to the empirical parameter. Thirty participants were recruited to evaluate the original and newly proposed camouflages. Paired sample t test indicates that the newly proposed military camouflage had a significant lower camouflage similarity index value and a longer detection time. The PSO shows to be a method with good results; however, a comprehensive study using multiple backgrounds and patterns would be required to generalize the methodology to other background environments or camouflage patterns.",
    url = "https://doi.org/10.1002/col.22404",
    doi = "10.1002/col.22404",
    openalex = "W2954985942",
    references = "doi101016japergo201901004"
}

Avoiding detection can provide significant survival advantages for prey, predators, or the military; conversely, maximizing visibility would be useful for signalling. One simple determinant of detectability is an animal's colour relative to its environment. But identifying the optimal colour to minimize (or maximize) detectability in a given natural environment is complex, partly because of the nature of the perceptual space. Here for the first time, using image processing techniques to embed targets into realistic environments together with psychophysics to estimate detectability and deep neural networks to interpolate between sampled colours, we propose a method to identify the optimal colour that either minimizes or maximizes visibility. We apply our approach in two natural environments (temperate forest and semi-arid desert) and show how a comparatively small number of samples can be used to predict robustly the most and least effective colours for camouflage. To illustrate how our approach can be generalized to other non-human visual systems, we also identify the optimum colours for concealment and visibility when viewed by simulated red-green colour-blind dichromats, typical for non-human mammals. Contrasting the results from these visual systems sheds light on why some predators seem, at least to humans, to have colouring that would appear detrimental to ambush hunting. We found that for simulated dichromatic observers, colour strongly affected detection time for both environments. In contrast, trichromatic observers were more effective at breaking camouflage.

@article{doi101098rsif20190183,
    author = "Fennell, John and Tálas, László and Baddeley, Roland and Cuthill, Innes C. and Scott‐Samuel, Nicholas E.",
    title = "Optimizing colour for camouflage and visibility using deep learning: the effects of the environment and the observer's visual system",
    year = "2019",
    journal = "Journal of The Royal Society Interface",
    abstract = "Avoiding detection can provide significant survival advantages for prey, predators, or the military; conversely, maximizing visibility would be useful for signalling. One simple determinant of detectability is an animal's colour relative to its environment. But identifying the optimal colour to minimize (or maximize) detectability in a given natural environment is complex, partly because of the nature of the perceptual space. Here for the first time, using image processing techniques to embed targets into realistic environments together with psychophysics to estimate detectability and deep neural networks to interpolate between sampled colours, we propose a method to identify the optimal colour that either minimizes or maximizes visibility. We apply our approach in two natural environments (temperate forest and semi-arid desert) and show how a comparatively small number of samples can be used to predict robustly the most and least effective colours for camouflage. To illustrate how our approach can be generalized to other non-human visual systems, we also identify the optimum colours for concealment and visibility when viewed by simulated red-green colour-blind dichromats, typical for non-human mammals. Contrasting the results from these visual systems sheds light on why some predators seem, at least to humans, to have colouring that would appear detrimental to ambush hunting. We found that for simulated dichromatic observers, colour strongly affected detection time for both environments. In contrast, trichromatic observers were more effective at breaking camouflage.",
    url = "https://doi.org/10.1098/rsif.2019.0183",
    doi = "10.1098/rsif.2019.0183",
    openalex = "W2947647869",
    references = "doi1010079781489945419, doi101098rstb20080217, doi101111j109583121990tb00839x, doi101111j251761611995tb02031x, doi1011171oe524041103, doi1011453065386, doi101163156856897x00357, doi1012019780429246593, doi107551mitpress32060010001, openalexw2025175823, openalexw2923742357"
}

Abstract Color selection for a camouflage pattern is a substantial part in designing an effective camouflage pattern. Current color selection methods are often based on the prevailing colors of digital images captured from a scene. However, color extraction from digital images has shown a major difference between the pattern color and the real environment colors. In this article, we present a more precise approach to camouflage color selection based on the spectrophotometric data of dominant objects in a scene. To this end, the dominant objects of a grassland scene were identified. The spectral reflectance of the dominant objects was measured and the percentage of each of them occurred in the scene was estimated. Then, the chromatic values of dominant objects were inserted into an existing camouflage pattern based on the occurrence of each dominant object in the scene. The performance of the obtained colors was assessed by calculating the color difference between the printed camouflage pattern and the dominant objects of the scene. The results showed that using a portable spectrophotometer instead of using a digital camera is more accurate for camouflage color selection and reduces the color difference from the surrounding environment. Furthermore, our method guarantees the absolute similarity between camouflage colors and terrain colors without using camouflage evaluation indexes or photo‐simulation assessment.

@article{doi101002col22587,
    author = "Daneshvar, Elaheh and Tehran, Mohammad Amani",
    title = "Optimal camouflage colors determination using spectral reflectance of real‐scene objects",
    year = "2020",
    journal = "Color Research \& Application",
    abstract = "Abstract Color selection for a camouflage pattern is a substantial part in designing an effective camouflage pattern. Current color selection methods are often based on the prevailing colors of digital images captured from a scene. However, color extraction from digital images has shown a major difference between the pattern color and the real environment colors. In this article, we present a more precise approach to camouflage color selection based on the spectrophotometric data of dominant objects in a scene. To this end, the dominant objects of a grassland scene were identified. The spectral reflectance of the dominant objects was measured and the percentage of each of them occurred in the scene was estimated. Then, the chromatic values of dominant objects were inserted into an existing camouflage pattern based on the occurrence of each dominant object in the scene. The performance of the obtained colors was assessed by calculating the color difference between the printed camouflage pattern and the dominant objects of the scene. The results showed that using a portable spectrophotometer instead of using a digital camera is more accurate for camouflage color selection and reduces the color difference from the surrounding environment. Furthermore, our method guarantees the absolute similarity between camouflage colors and terrain colors without using camouflage evaluation indexes or photo‐simulation assessment.",
    url = "https://doi.org/10.1002/col.22587",
    doi = "10.1002/col.22587",
    openalex = "W3092752473",
    references = "doi101002col22352, doi101016jneucom201412108, doi101038nature03312, doi101098rspb20063615, doi101098rstb20080216, doi101098rstb20080218, doi1011112041210x12439, doi1011112041210x13328, doi101111jzo12682, doi1011171oe524041103, doi1023071936109"
}

Camouflage helps animals to hide from predators and is therefore key to survival. Although widespread convergence of animal phenotypes to their natural environment is well-established, there is a lack of knowledge about how species compromise camouflage accuracy across different background types in their habitat. Here we tested how background matching has responded to top-down selection by avian and mammalian predators using Sahara-Sahel desert rodents in North Africa. We show that the fur colouration of several species has become an accurate match to different types of desert habitats. This is supported by a correlation analysis of colour and pattern metrics, investigation of animal-to-background similarities at different spatial scales and is confirmed by modelling of two predator vision systems. The background match was closest across large (or global) spatial scales, suggesting a generalist camouflage tactic for many background types. Some species, may have a better match to the background over small (or focal) spatial scales, which could be the result of habitat choices or differential predation. Nevertheless, predicted discrimination distances of fur colouration were virtually indistinguishable for mammalian and low for avian vision model, which implies effective camouflage. Our study provides one of the best documented cases of multilevel camouflage accuracy in geographically widespread taxa. We conclude that background matching has become an effective and common adaptation against predatory threat in Sahara-Sahelian desert rodents.

@article{doi1011111365265613225,
    author = "Nokelainen, Ossi and Brito, José Carlos and Scott‐Samuel, Nicholas E. and Valkonen, Janne K. and Boratyński, Zbyszek",
    title = "Camouflage accuracy in Sahara–Sahel desert rodents",
    year = "2020",
    journal = "Journal of Animal Ecology",
    abstract = "Camouflage helps animals to hide from predators and is therefore key to survival. Although widespread convergence of animal phenotypes to their natural environment is well-established, there is a lack of knowledge about how species compromise camouflage accuracy across different background types in their habitat. Here we tested how background matching has responded to top-down selection by avian and mammalian predators using Sahara-Sahel desert rodents in North Africa. We show that the fur colouration of several species has become an accurate match to different types of desert habitats. This is supported by a correlation analysis of colour and pattern metrics, investigation of animal-to-background similarities at different spatial scales and is confirmed by modelling of two predator vision systems. The background match was closest across large (or global) spatial scales, suggesting a generalist camouflage tactic for many background types. Some species, may have a better match to the background over small (or focal) spatial scales, which could be the result of habitat choices or differential predation. Nevertheless, predicted discrimination distances of fur colouration were virtually indistinguishable for mammalian and low for avian vision model, which implies effective camouflage. Our study provides one of the best documented cases of multilevel camouflage accuracy in geographically widespread taxa. We conclude that background matching has become an effective and common adaptation against predatory threat in Sahara-Sahelian desert rodents.",
    url = "https://doi.org/10.1111/1365-2656.13225",
    doi = "10.1111/1365-2656.13225",
    openalex = "W3013479376",
    references = "doi101098rsif20190183"
}

Camouflage plays an indispensable role in modern military. Generally, a camouflage pattern includes a plurality of shapes units, which are split by elemental colors. The fixed camouflage pattern is low adaptability and concealability for changeable battlefields. Moreover, the conventionally camouflage design is time and resource consuming for manual drawing. In this paper, we propose a dynamic camouflage synthesizing method. Firstly, the texture patterns of one class of battlefield images is extracted using convolutional transfer network. We use 3*3 convolution kernels to extract texture features. And the covariance matrix is used as loss function to calculate the loss of different image texture features. Colors construction and their distribution of the specified battlefield images is extracted according to a clustering-based algorithm. Finally, the statistical color units are embedded into the texture patterns. We assess the adaptability and the concealability of synthesized camouflage using Eye Tracking based criteria. Comparing to the People's Liberation Army Type 87 woodland pattern and the digital camouflage pattern synthesized using our previous method, testing results of our synthesized camouflage patterns were better in different saccade indicators. This demonstrates camouflage pattern synthesize proposed got better concealment and the validity of proposed method. Besides, we also compared our method with local binary pattern for extracting texture features. The experiments results indicated the method proposed had better consistency to the scene images.

@article{doi101109access20213077258,
    author = "Wei, Xinjian and Li, Guangxu and Wang, Kaidi",
    title = "A Novel Method for Automatic Camouflage Pattern Synthesize",
    year = "2021",
    journal = "IEEE Access",
    abstract = "Camouflage plays an indispensable role in modern military. Generally, a camouflage pattern includes a plurality of shapes units, which are split by elemental colors. The fixed camouflage pattern is low adaptability and concealability for changeable battlefields. Moreover, the conventionally camouflage design is time and resource consuming for manual drawing. In this paper, we propose a dynamic camouflage synthesizing method. Firstly, the texture patterns of one class of battlefield images is extracted using convolutional transfer network. We use 3*3 convolution kernels to extract texture features. And the covariance matrix is used as loss function to calculate the loss of different image texture features. Colors construction and their distribution of the specified battlefield images is extracted according to a clustering-based algorithm. Finally, the statistical color units are embedded into the texture patterns. We assess the adaptability and the concealability of synthesized camouflage using Eye Tracking based criteria. Comparing to the People's Liberation Army Type 87 woodland pattern and the digital camouflage pattern synthesized using our previous method, testing results of our synthesized camouflage patterns were better in different saccade indicators. This demonstrates camouflage pattern synthesize proposed got better concealment and the validity of proposed method. Besides, we also compared our method with local binary pattern for extracting texture features. The experiments results indicated the method proposed had better consistency to the scene images.",
    url = "https://doi.org/10.1109/access.2021.3077258",
    doi = "10.1109/access.2021.3077258",
    openalex = "W3161260479"
}

Evolutionary biologists frequently wish to measure the fitness of alternative phenotypes using behavioral experiments. However, many phenotypes are complex. One example is coloration: camouflage aims to make detection harder, while conspicuous signals (e.g., for warning or mate attraction) require the opposite. Identifying the hardest and easiest to find patterns is essential for understanding the evolutionary forces that shape protective coloration, but the parameter space of potential patterns (colored visual textures) is vast, limiting previous empirical studies to a narrow range of phenotypes. Here, we demonstrate how deep learning combined with genetic algorithms can be used to augment behavioral experiments, identifying both the best camouflage and the most conspicuous signal(s) from an arbitrarily vast array of patterns. To show the generality of our approach, we do so for both trichromatic (e.g., human) and dichromatic (e.g., typical mammalian) visual systems, in two different habitats. The patterns identified were validated using human participants; those identified as the best for camouflage were significantly harder to find than a tried-and-tested military design, while those identified as most conspicuous were significantly easier to find than other patterns. More generally, our method, dubbed the "Camouflage Machine," will be a useful tool for identifying the optimal phenotype in high dimensional state spaces.

@article{doi101111evo14162,
    author = "Fennell, John and Tálas, László and Baddeley, Roland and Cuthill, Innes C. and Scott‐Samuel, Nicholas E.",
    title = "The Camouflage Machine: Optimizing protective coloration using deep learning with genetic algorithms",
    year = "2021",
    journal = "Evolution",
    abstract = {Evolutionary biologists frequently wish to measure the fitness of alternative phenotypes using behavioral experiments. However, many phenotypes are complex. One example is coloration: camouflage aims to make detection harder, while conspicuous signals (e.g., for warning or mate attraction) require the opposite. Identifying the hardest and easiest to find patterns is essential for understanding the evolutionary forces that shape protective coloration, but the parameter space of potential patterns (colored visual textures) is vast, limiting previous empirical studies to a narrow range of phenotypes. Here, we demonstrate how deep learning combined with genetic algorithms can be used to augment behavioral experiments, identifying both the best camouflage and the most conspicuous signal(s) from an arbitrarily vast array of patterns. To show the generality of our approach, we do so for both trichromatic (e.g., human) and dichromatic (e.g., typical mammalian) visual systems, in two different habitats. The patterns identified were validated using human participants; those identified as the best for camouflage were significantly harder to find than a tried-and-tested military design, while those identified as most conspicuous were significantly easier to find than other patterns. More generally, our method, dubbed the "Camouflage Machine," will be a useful tool for identifying the optimal phenotype in high dimensional state spaces.},
    url = "https://doi.org/10.1111/evo.14162",
    doi = "10.1111/evo.14162",
    openalex = "W3119202755",
    references = "doi101098rsif20190183"
}

Carotenoids are pigments responsible for most bright yellow, red, and orange hues in birds. Their distribution has been investigated in avian plumage, but the evolution of their expression in skin and other integumentary structures has not been approached in detail. Here, we investigate the expression of carotenoid-consistent coloration across tissue types in all extant, nonpasserine species (n = 4022) and archelosaur outgroups in a phylogenetic framework. We collect dietary data for a subset of birds and investigate how dietary carotenoid intake may relate to carotenoid expression in various tissues. We find that carotenoid-consistent expression in skin or nonplumage keratin has a 50% probability of being present in the most recent common ancestor of Archosauria. Skin expression has a similar probability at the base of the avian crown clade, but plumage expression is unambiguously absent in that ancestor and shows hundreds of independent gains within nonpasserine neognaths, consistent with previous studies. Although our data do not support a strict sequence of tissue expression in nonpasserine birds, we find support that expression of carotenoid-consistent color in nonplumage integument structures might evolve in a correlated manner and feathers are rarely the only region of expression. Taxa with diets high in carotenoid content also show expression in more body regions and tissue types. Our results may inform targeted assays for carotenoids in tissues other than feathers, and expectations of these pigments in nonavian dinosaurs. In extinct groups, bare-skin regions and the rhamphotheca, especially in species with diets rich in plants, may express these pigments, which are not expected in feathers or feather homologues.

@article{doi101111evo14393,
    author = "Davis, Sarah N. and Clarke, Julia A.",
    title = "Estimating the distribution of carotenoid coloration in skin and integumentary structures of birds and extinct dinosaurs",
    year = "2021",
    journal = "Evolution",
    abstract = "Carotenoids are pigments responsible for most bright yellow, red, and orange hues in birds. Their distribution has been investigated in avian plumage, but the evolution of their expression in skin and other integumentary structures has not been approached in detail. Here, we investigate the expression of carotenoid-consistent coloration across tissue types in all extant, nonpasserine species (n = 4022) and archelosaur outgroups in a phylogenetic framework. We collect dietary data for a subset of birds and investigate how dietary carotenoid intake may relate to carotenoid expression in various tissues. We find that carotenoid-consistent expression in skin or nonplumage keratin has a 50\% probability of being present in the most recent common ancestor of Archosauria. Skin expression has a similar probability at the base of the avian crown clade, but plumage expression is unambiguously absent in that ancestor and shows hundreds of independent gains within nonpasserine neognaths, consistent with previous studies. Although our data do not support a strict sequence of tissue expression in nonpasserine birds, we find support that expression of carotenoid-consistent color in nonplumage integument structures might evolve in a correlated manner and feathers are rarely the only region of expression. Taxa with diets high in carotenoid content also show expression in more body regions and tissue types. Our results may inform targeted assays for carotenoids in tissues other than feathers, and expectations of these pigments in nonavian dinosaurs. In extinct groups, bare-skin regions and the rhamphotheca, especially in species with diets rich in plants, may express these pigments, which are not expected in feathers or feather homologues.",
    url = "https://doi.org/10.1111/evo.14393",
    doi = "10.1111/evo.14393",
    openalex = "W3209373684",
    references = "doi107717peerj5831"
}

@incollection{crossref2022concealing,
    title = "Concealing Coloration",
    year = "2022",
    booktitle = "Encyclopedia of Animal Cognition and Behavior",
    url = "https://doi.org/10.1007/978-3-319-55065-7\_300461",
    doi = "10.1007/978-3-319-55065-7\_300461",
    pages = "1602-1602"
}

Abstract Optical stealth technology is being developed to cope with high‐sensitivity infrared image detectors and various guided detectors. Infrared stealth technology has remarkable performance; however, future advancements in multi‐band stealth technology covering the entire optical frequency range, from visible to wide infrared, are key challenges regarding unmanned surveillance systems. Thus, a metal–semiconductor–metal (MSM) metasurface with Fabry–Pérot (F–P) and multiple plasmonic resonant modes is introduced to realize multiband stealth technology. Different colors are obtained for printing camouflage patterns in the visible range using localized surface plasmon modes in Al disks on an opaque Ge layer. The F–P resonance of the Ge layer induces a strong absorption of >92% at 1.06 µm, reducing the guidance signal of the infrared laser‐guided detector. With an additional plasmonic resonance in the MSM metasurface, infrared signature reductions of >34%, >94.4%, and >97.7% are obtained for short‐wave, mid‐wave, and long‐wave infrared bands, respectively.

@article{doi101002adom202101930,
    author = "Kim, Jagyeong and Park, Changhoon and Hahn, Jae W.",
    title = "Metal–Semiconductor–Metal Metasurface for Multiband Infrared Stealth Technology Using Camouflage Color Pattern in Visible Range",
    year = "2022",
    journal = "Advanced Optical Materials",
    abstract = "Abstract Optical stealth technology is being developed to cope with high‐sensitivity infrared image detectors and various guided detectors. Infrared stealth technology has remarkable performance; however, future advancements in multi‐band stealth technology covering the entire optical frequency range, from visible to wide infrared, are key challenges regarding unmanned surveillance systems. Thus, a metal–semiconductor–metal (MSM) metasurface with Fabry–Pérot (F–P) and multiple plasmonic resonant modes is introduced to realize multiband stealth technology. Different colors are obtained for printing camouflage patterns in the visible range using localized surface plasmon modes in Al disks on an opaque Ge layer. The F–P resonance of the Ge layer induces a strong absorption of >92\% at 1.06 µm, reducing the guidance signal of the infrared laser‐guided detector. With an additional plasmonic resonance in the MSM metasurface, infrared signature reductions of >34\%, >94.4\%, and >97.7\% are obtained for short‐wave, mid‐wave, and long‐wave infrared bands, respectively.",
    url = "https://doi.org/10.1002/adom.202101930",
    doi = "10.1002/adom.202101930",
    openalex = "W4206914954",
    references = "doi101016jmattod202011013"
}

≈ 0.143). Due to its flexibility and scalability, the compatible camouflage film can be applied in practical applications and exhibits desirable visible and infrared camouflage performance in different battlefield backgrounds.

@article{doi101002advs202303452,
    author = "Xiong, Yuqin and Zhou, Yitong and Tian, Junlong and Wang, Wanlin and Zhang, Wang and Zhang, Di",
    title = "Scalable, Color‐Matched, Flexible Plasmonic Film for Visible–Infrared Compatible Camouflage",
    year = "2023",
    journal = "Advanced Science",
    abstract = "≈ 0.143). Due to its flexibility and scalability, the compatible camouflage film can be applied in practical applications and exhibits desirable visible and infrared camouflage performance in different battlefield backgrounds.",
    url = "https://doi.org/10.1002/advs.202303452",
    doi = "10.1002/advs.202303452",
    openalex = "W4387966386",
    references = "doi101002adma202004754, doi101002adom201801006, doi101002advs202303452, doi101016jinfrared201811001, doi101016jmattod202011013, doi101016jnanoen2020104449, doi101021nl061851t, doi101038ncomms7368, doi101038s4137701902311, doi101038s4137702003005, doi101038s41467017026788, doi101038s41467021220510"
}

Color and pattern are integral parts of the visual characteristics of camouflage. These means, taking into account the experience of military operations during the Russian-Ukrainian war, can significantly increase the survivability and safety of personnel, weapons and military equipment, by eliminating the characteristic unmasking signs of these military facilities and hiding them on vegetative, desert-steppe, snowy and urbanized areas background. The paper considers the first stage in the design of camouflage means of concealment - the identification of the characteristic colors of the area. The identification of characteristic colors is proposed to be carried out using clustering related to unsupervised machine learning methods. The number of clusters determines the number of colors that will be displayed on the masking surface. It was determined that it is advisable to analyze terrain images stored in the digital JPEG format, and the colors are represented in the RGB additive color model. When conducting research, such a clustering method for image analysis as k-means was used, which has an advantage over other clustering methods in ease of implementation, unpretentiousness in resources and sufficient computational speed. Other clustering methods, such as hierarchical or density-based, have not proven to be suitable for image clustering. The comparison was made with the most common clustering methods: c-means, DBSCAN, OPTICS, agglomerative, spectral biclustering, etc. Various algorithmic approaches to choosing the number of clusters were tested, according to the results of the experiments, the “elbow” method was chosen as the most optimal one. Mathematical algorithms were taken from open sources, their implementation was carried out using common software libraries for machine learning of the Python programming language. The results of the work made it possible to choose mathematical algorithms for determining the number of colors of camouflage means of concealment. This will allow to analyze the terrain of all natural zones of Ukraine and design effective camouflage coverings for the Armed Forces of Ukraine.

@article{doi103357723124458282023114123,
    author = "Tsybulia, Serhii",
    title = "Determination of the characteristic colors of the terrain in the development of camouflage means",
    year = "2023",
    journal = "Military Technical Collection",
    abstract = "Color and pattern are integral parts of the visual characteristics of camouflage. These means, taking into account the experience of military operations during the Russian-Ukrainian war, can significantly increase the survivability and safety of personnel, weapons and military equipment, by eliminating the characteristic unmasking signs of these military facilities and hiding them on vegetative, desert-steppe, snowy and urbanized areas background. The paper considers the first stage in the design of camouflage means of concealment - the identification of the characteristic colors of the area. The identification of characteristic colors is proposed to be carried out using clustering related to unsupervised machine learning methods. The number of clusters determines the number of colors that will be displayed on the masking surface. It was determined that it is advisable to analyze terrain images stored in the digital JPEG format, and the colors are represented in the RGB additive color model. When conducting research, such a clustering method for image analysis as k-means was used, which has an advantage over other clustering methods in ease of implementation, unpretentiousness in resources and sufficient computational speed. Other clustering methods, such as hierarchical or density-based, have not proven to be suitable for image clustering. The comparison was made with the most common clustering methods: c-means, DBSCAN, OPTICS, agglomerative, spectral biclustering, etc. Various algorithmic approaches to choosing the number of clusters were tested, according to the results of the experiments, the “elbow” method was chosen as the most optimal one. Mathematical algorithms were taken from open sources, their implementation was carried out using common software libraries for machine learning of the Python programming language. The results of the work made it possible to choose mathematical algorithms for determining the number of colors of camouflage means of concealment. This will allow to analyze the terrain of all natural zones of Ukraine and design effective camouflage coverings for the Armed Forces of Ukraine.",
    url = "https://doi.org/10.33577/2312-4458.28.2023.114-123",
    doi = "10.33577/2312-4458.28.2023.114-123",
    openalex = "W4379161185",
    references = "doi101016jdt202010002"
}

-based nanocavity structure offers a competitive strategy for visible-compatible adaptive thermal camouflage in practice.

@article{doi101021acsami5c07199,
    author = "Wu, Zuoxu and Ai, Xun and Wang, Jian and Sun, Xiaoyu and Li, Derun and Mao, Jun and Wang, Xinyu and Zhang, Qian and Cao, Feng",
    title = "W x V 1– x O 2 -Based Nanocavity for Adaptive Thermal Camouflage with Visual Coloration",
    year = "2025",
    journal = "ACS Applied Materials \& Interfaces",
    abstract = "-based nanocavity structure offers a competitive strategy for visible-compatible adaptive thermal camouflage in practice.",
    url = "https://doi.org/10.1021/acsami.5c07199",
    doi = "10.1021/acsami.5c07199",
    openalex = "W4412772082",
    references = "doi101016jcej2024156128"
}

The multimodal detection system has gradually been perfected, essentially covering the entire optical spectrum, posing a significant threat to the survival of objects. To counter this escalating detection threat, the demand for multispectral-compatible camouflage (MCC) is increasingly urgent. However, there are inherent conflicts in the principles of camouflage for visible light, infrared (IR), and lasers, necessitating spectrally selective design to reconcile these conflicting requirements. Here, we propose a multilayer film structure with heterostructure coupling, utilizing resonant cavities, destructive interference, and double-metal defect layers to achieve MCC, integrating IR, laser, and visible light. These MCC films exhibit low emissivity in the dual IR bands (∼0.2 at 3-5 μm and ∼0.4 at 7.5-13 μm) for high-temperature thermal camouflage, low reflectance at 10.6 μm (∼0.3) for reducing laser signal, and demonstrate excellent insensitivity to angles and polarization. By varying the thickness of the resonant cavity, a wide color gamut in the visible light range is achieved, maintaining efficient IR and laser compatibility while integrating diverse structural colors. This work offers a promising and pattern-free method for MCC design, holding great potential in thermal management and camouflage.

@article{doi101515nanoph20250303,
    author = "Wang, Wenhao and Wang, Long and Liu, Tonghao and Cui, Yina and Wang, Liuying and Liu, Gu and Pang, Yan and Wu, Xiao and Zhu, Xinyu and Chi, Xiaochun and Yang, Haoke and Wu, Xiaohu",
    title = "Structural‐color‐enabled multispectral heterostructure for infrared and laser camouflage",
    year = "2025",
    journal = "Nanophotonics",
    abstract = "The multimodal detection system has gradually been perfected, essentially covering the entire optical spectrum, posing a significant threat to the survival of objects. To counter this escalating detection threat, the demand for multispectral-compatible camouflage (MCC) is increasingly urgent. However, there are inherent conflicts in the principles of camouflage for visible light, infrared (IR), and lasers, necessitating spectrally selective design to reconcile these conflicting requirements. Here, we propose a multilayer film structure with heterostructure coupling, utilizing resonant cavities, destructive interference, and double-metal defect layers to achieve MCC, integrating IR, laser, and visible light. These MCC films exhibit low emissivity in the dual IR bands (∼0.2 at 3-5 μm and ∼0.4 at 7.5-13 μm) for high-temperature thermal camouflage, low reflectance at 10.6 μm (∼0.3) for reducing laser signal, and demonstrate excellent insensitivity to angles and polarization. By varying the thickness of the resonant cavity, a wide color gamut in the visible light range is achieved, maintaining efficient IR and laser compatibility while integrating diverse structural colors. This work offers a promising and pattern-free method for MCC design, holding great potential in thermal management and camouflage.",
    url = "https://doi.org/10.1515/nanoph-2025-0303",
    doi = "10.1515/nanoph-2025-0303",
    openalex = "W4413943200",
    references = "doi101364oe515968"
}

Increasing pressure on the Amazon rainforest from illegal mining and deforestation threatens biodiversity. Monitoring such vast and remote territories remains challenging, and the performance of technological monitoring systems largely depends on their ability to withstand harsh environmental conditions and operate unattended for long periods. This article presents the deployment of a Remote Monitoring System (RMS) in the Colombian Amacayacu National Natural Park designed to detect unauthorized entries into the park via waterways. It addresses two critical operational challenges frequently underreported in the literature: equipment protection against environmental conditions and strategies to reduce vandalism or theft. The results demonstrate that appropriate enclosure design, material selection, and camouflage strategies can improve the operational robustness of RMS deployed in humid tropical environments. This experience provides practical design insights and recommendations to support future deployments of long-term outdoor monitoring technologies.

@article{doi101002ece373491,
    author = "Barajas, María and Torres, Jorge and Ortiz, Paula and Triana, Andrés and Varon, Margarita",
    title = "Enclosure and Camouflage Design of a Prototype Remote Monitoring System for the Protection and Conservation of Territories in the Colombian Amazon Rainforest.",
    year = "2026",
    journal = "Ecology and evolution",
    abstract = "Increasing pressure on the Amazon rainforest from illegal mining and deforestation threatens biodiversity. Monitoring such vast and remote territories remains challenging, and the performance of technological monitoring systems largely depends on their ability to withstand harsh environmental conditions and operate unattended for long periods. This article presents the deployment of a Remote Monitoring System (RMS) in the Colombian Amacayacu National Natural Park designed to detect unauthorized entries into the park via waterways. It addresses two critical operational challenges frequently underreported in the literature: equipment protection against environmental conditions and strategies to reduce vandalism or theft. The results demonstrate that appropriate enclosure design, material selection, and camouflage strategies can improve the operational robustness of RMS deployed in humid tropical environments. This experience provides practical design insights and recommendations to support future deployments of long-term outdoor monitoring technologies.",
    url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC13096577/",
    doi = "10.1002/ece3.73491",
    pmcid = "PMC13096577",
    pmid = "42023037"
}

Canal construction activities alter the visual characteristics of natural habitats, which in turn impairs the camouflage effectiveness of resident animals. To explore the impacts of habitat degradation induced by anthropogenic engineering on the camouflage strategies of sympatric crab species, this study investigated the camouflage performance of Chiromantes haematocheir and Orisarma dehaani in natural estuarine habitats and canal-modified estuarine habitats of the Pinglu Canal. The Chromatic Just Noticeable Difference (CJND) of C. haematocheir in canal-modified habitats was 16.272 ± 9.503, significantly higher than the value of 12.911 ± 7.982 in natural estuaries (Z = -6.514, p < 0.001). Within the same habitat type, the CJND value of O. dehaani was consistently and significantly lower than that of C. haematocheir, with significant differences observed in both natural estuaries (Z = -11.572, p < 0.001) and canal-modified habitats (Z = -13.413, p < 0.001). Meanwhile, the pattern energy difference (PED) of O. dehaani in canal-modified habitats (0.744 ± 0.119) was significantly higher than that in natural estuaries (0.726 ± 0.107; Z = -2.390, p = 0.017), and the PED of C. haematocheir in canal-modified habitats (0.750 ± 0.133) was significantly higher than that in natural estuaries (0.731 ± 0.122; Z = -2.742, p = 0.006). The Pinglu Canal's construction significantly exacerbated the reduction in background-matching camouflage effectiveness of both crab species. This study provides empirical evidence for evaluating the impacts of anthropogenic engineering activities on the camouflage adaptability of estuarine benthic animals, and offers a scientific reference for the conservation of benthic biological resources in canal-modified estuarine ecosystems.

@article{doi103390biology15080651,
    author = "Zhai, Binyu and Lai, Fuxi and Lu, Sichen and Deng, Xinglai and Li, Wenjie and Yang, Lin and Deng, Changyin and Wu, Zhihong and Huang, Yiran and Wang, Haitao and Liao, Yuhao and Bu, Rongping",
    title = "Effects of Pinglu Canal Construction on Camouflage in Two Sesarmid Crab Species.",
    year = "2026",
    journal = "Biology",
    abstract = "Canal construction activities alter the visual characteristics of natural habitats, which in turn impairs the camouflage effectiveness of resident animals. To explore the impacts of habitat degradation induced by anthropogenic engineering on the camouflage strategies of sympatric crab species, this study investigated the camouflage performance of Chiromantes haematocheir and Orisarma dehaani in natural estuarine habitats and canal-modified estuarine habitats of the Pinglu Canal. The Chromatic Just Noticeable Difference (CJND) of C. haematocheir in canal-modified habitats was 16.272 ± 9.503, significantly higher than the value of 12.911 ± 7.982 in natural estuaries (Z = -6.514, p < 0.001). Within the same habitat type, the CJND value of O. dehaani was consistently and significantly lower than that of C. haematocheir, with significant differences observed in both natural estuaries (Z = -11.572, p < 0.001) and canal-modified habitats (Z = -13.413, p < 0.001). Meanwhile, the pattern energy difference (PED) of O. dehaani in canal-modified habitats (0.744 ± 0.119) was significantly higher than that in natural estuaries (0.726 ± 0.107; Z = -2.390, p = 0.017), and the PED of C. haematocheir in canal-modified habitats (0.750 ± 0.133) was significantly higher than that in natural estuaries (0.731 ± 0.122; Z = -2.742, p = 0.006). The Pinglu Canal's construction significantly exacerbated the reduction in background-matching camouflage effectiveness of both crab species. This study provides empirical evidence for evaluating the impacts of anthropogenic engineering activities on the camouflage adaptability of estuarine benthic animals, and offers a scientific reference for the conservation of benthic biological resources in canal-modified estuarine ecosystems.",
    url = "https://pubmed.ncbi.nlm.nih.gov/42041931/",
    doi = "10.3390/biology15080651",
    pmid = "42041931"
}