The purpose of camouflage is to be inconspicuous against a given background. Colour is an important component of camouflage, and the task of designing a single camouflage pattern for use against multiple different backgrounds is particularly challenging. As it is impossible to match the colour gamut of each background exactly, the question arises which colours from the different backgrounds should be incorporated in a camouflage pattern to achieve optimal concealment. Here, we used a visual search paradigm to address this question. Observers searched multi-coloured continuous textures for target regions defined by either the presence or absence of additional hues. Targets could be either a combination of five hues against a four-hued background (“patches”), or a combination of four hues against a five-hued background (“holes”). In Experiment 1, a search asymmetry was observed for the different targets, as observers were less accurate and slower at detecting holes than patches. Additionally, we observed a linear separability effect: search for a target was more difficult when the hue that defined the target was within the gamut of distractor colours (e.g. orange amongst reds and yellows). In Experiment 2, we further investigated “hole” targets designed for two different backgrounds and found that optimal concealment against both backgrounds was achieved by including intermediate colours that represented a compromise between the common colours and the unique colours of each background. The findings provide insights into how search asymmetries can be extended to complex texture properties and help inform the design process of camouflage for multiple backgrounds.

伪装的目的是在给定的背景下不显眼。颜色是伪装的重要组成部分，设计用于多种不同背景的单一伪装图案的任务尤其具有挑战性。由于不可能精确匹配每个背景的色域，因此出现了一个问题，即应该将来自不同背景的哪些颜色结合到迷彩图案中以实现最佳隐藏效果。在这里，我们使用视觉搜索范式来解决这个问题。观察者在多色连续纹理中搜索由是否存在附加色调定义的目标区域。目标可以是四种色调背景的五种色调组合（“补丁”），也可以是五种色调背景的四种色调的组合（“孔”）。在实验 1 中，观察到不同目标的搜索不对称性，因为与补丁相比，观察者检测漏洞的准确度较低且速度较慢。此外，我们观察到线性可分性效应：当定义目标的色调在干扰色域内（例如红色和黄色之间的橙色）时，搜索目标会更加困难。在实验 2 中，我们进一步研究了为两种不同背景设计的“洞”目标，发现对两种背景都是通过包括中间色来实现的，中间色代表了每个背景的常见颜色和独特颜色之间的折衷。这些发现提供了有关如何将搜索不对称扩展到复杂纹理属性的见解，并有助于为多种背景的伪装设计过程提供信息。