Data from: Image Calibration and Analysis Toolbox – a free software suite for measuring reflectance, colour, and pattern objectively and to animal vision

1. Quantitative measurements of colour, pattern, and morphology are vital to a growing range of disciplines. Digital cameras are readily available and already widely used for making these measurements, having numerous advantages over other techniques, such as spectrometry. However, off-the-shelf consumer cameras are designed to produce images for human viewing, meaning that their uncalibrated photographs cannot be used for making reliable, quantitative measurements. Many studies still fail to appreciate this, and of those scientists who are aware of such issues, many are hindered by a lack usable tools for making objective measurements from photographs. 2. We have developed an image processing toolbox that generates images that are linear with respect to radiance from the RAW files of numerous camera brands, and can combine image channels from multispectral cameras, including additional ultraviolet photographs. Images are then normalised using one or more grey standards to control for lighting conditions. This enables objective measures of reflectance and colour using a wide range of consumer cameras. Furthermore, if the camera's spectral sensitivities are known, the software can convert images to correspond to the visual system (cone-catch values) of a wide range of animals, enabling human and non-human visual systems to be modelled. The toolbox also provides image analysis tools that can extract luminance (lightness), colour, and pattern information. Furthermore, all processing is performed on 32-bit floating point images rather than commonly used 8-bit images. This increases precision and reduces the likelihood of data loss through rounding error or saturation of pixels, while also facilitating the measurement of objects with shiny or fluorescent properties. 3. All cameras tested using this software were found to demonstrate a linear response within each image and across a range of exposure times. Cone-catch mapping functions were highly robust, converting images to several animal visual systems and yielding data that agreed closely with spectrometer-based estimates. 4. Our imaging toolbox is freely available as an addition to the open source ImageJ software. We believe that it will considerably enhance the appropriate use of digital cameras across multiple areas of biology, in particular researchers aiming to quantify animal and plant visual signals.

1. 颜色、图案与形态学的定量测量，对日益增多的学科领域至关重要。数码相机易于获取且已被广泛用于此类测量，相较光谱法等其他技术具备诸多优势。然而，市售消费级数码相机（off-the-shelf consumer cameras）的设计初衷是为人类视觉呈现图像，因此其未经过校准的照片无法用于可靠的定量测量。当前仍有大量研究未意识到这一局限，而即便知晓该问题的研究者，也常因缺乏可从照片中获取客观测量结果的可用工具而受阻。
2. 我们开发了一款图像处理工具箱，可基于多款相机品牌的RAW格式文件（RAW files）生成与辐亮度（radiance）呈线性关系的图像，还可整合多光谱相机（multispectral cameras）的图像通道，包括额外的紫外拍摄图像。随后可通过一个或多个灰度校准标准对图像进行归一化处理，以控制光照条件的影响。这使得我们能够借助各类消费级数码相机，实现反射率与颜色的客观测量。此外，若已知相机的光谱灵敏度参数，该软件可将图像转换为对应多种动物视觉系统的锥细胞捕获值（cone-catch values），从而实现人类与非人类视觉系统的建模。该工具箱还提供图像分析工具，可提取亮度（明度）、颜色与图案信息。值得注意的是，所有处理均基于32位浮点图像（而非常用的8位图像）完成，这提升了计算精度，降低了因像素舍入误差或像素饱和导致的数据丢失风险，同时也便于测量具有光泽或荧光特性的物体。
3. 使用该软件测试的所有相机，均在单幅图像内部以及不同曝光时长范围内表现出线性响应特性。锥细胞捕获值映射函数具备极强的鲁棒性，可将图像转换为多种动物的视觉系统对应数据，所得结果与基于光谱法的估算值高度吻合。
4. 我们的成像工具箱可作为开源ImageJ软件的扩展插件免费获取。我们相信，该工具箱将大幅提升数码相机在多个生物学领域的合理应用，尤其有助于致力于量化动植物视觉信号的研究人员开展相关工作。