Colour to grey scale and related transforms

每年，数以百万计的彩色图像的灰度复制品。通过我们的研究，我们的目标是使数以百万计的更好的灰度打印。现在，使用彩色数码相机拍摄图像并将其显示在彩色显示器或彩色喷墨打印机上越来越普遍。然而，仍有许多情况下，彩色图像以灰度再现。使用黑白白色打印机、复印机和传真机仍然是每天发生的事情。不幸的是，通过这些设备或通过其他手段将彩色图像转换为它们的灰度等效物通常导致图像的差的再现。我们的研究的目的是开发一种方法，以获得最佳的灰度再现的彩色图像，通过仔细考虑我们自己的视觉系统的局限性，并通过利用彩色图像形成的基本物理。通常，给定图像点处的颜色由三个数字编码，并且在灰度变换中，这三个数字被减少为仅一个灰度值。更一般地，颜色信息可以使用N（其中N>3）个数字来编码，并且在这种情况下，能够导出将这N个数字减少到3或更少的方法是有用的，使得所记录的N维信息可以在常规成像技术上显示。我们将扩大我们的研究，也考虑这样的情况。我们的研究将导致改进灰度设备上的图像复制（例如改进的复印和传真），以及为我们提供更好地可视化包含在例如卫星图像中的信息的能力。我们还希望有可能利用我们开发的技术来制作彩色图像，这些图像可以被色盲观察者无错误或混淆地观看。此外，这项工作将导致现有图像处理算法的改进，并更好地了解我们自己的视觉系统如何感知颜色和亮度信息。

Every year, millions of poor grey scale reproductions of colour images are made. Through our research we aim to make millions more good grey scale prints.It is now increasingly common to capture images using colour digital cameras and display them on colour monitors or using colour inkjet printers. However, there are still many occasions when colour images are reproduced in greyscale. The use of black and white printers, photocopiers and fax machines is still an every day occurrence. Unfortunately, the conversion of colour images to their greyscale equivalent, either by these devices, or through other means, often results in a poor reproduction of the images. The aim of our research is to develop a method to derive the best possible greyscale reproduction of a colour image, by a careful consideration of the limitations of our own visual system, and by exploiting the underlying physics of colour image formation. Usually, the colour at a given image point is coded by three numbers, and in the greyscale transformation these three numbers are reduced to just one grey value. More generally, colour information might be coded using N (where N>3) numbers, and in this case it is useful to be able to derive methods to reduce these N numbers to 3, or fewer, so that the N-dimensional information recorded can be displayed on conventional imaging technology. We will extend our research to also consider such cases. Our research will lead to the improved reproduction of images on greyscale devices (e.g. improved photocopying and faxing) as well as providing us with the ability to better visualise the information contained in, for example, satellite images. We also expect that it will be possible to exploit the technology we develop to make colour images that can be viewed without error or confusion, by colour-blind observers. In addition, the work will lead to improvements in existing image processing algorithms, and to a better understanding of how our own visual system perceives colour and brightness information.