关于imread和rgb2gray的数组值

问题描述

对于给定的图像，如果我使用imread读取图像，则三个通道中的值是否会在[0,255]的范围内?如果我使用rgb2gray传输此图像，该值是否在[0,1]范围内?

For a given image, if I read it using imread, will the values in the three channels be in the range of [0,255]? If I transfer this image using rgb2gray, will the value be in the range of [0,1]?

基于 skimage文档，rgb2gray的计算结果为

based on the skimage doc, the calculation of rgb2gray is

Y = 0.2125 R + 0.7154 G + 0.0721 B

在我看来，这不能保证rgb2gray的结果将始终属于[0,1].这有点困惑.

It seems to me that it cannot guarantee the result of rgb2gray will always belong to [0,1]. This is a bit confused.

推荐答案

当scikit-image中的图像转换为浮点(即非整数)类型时，它们将转换为[0，1]范围.因此，rgb2gray中的管道首先要除以255，然后再乘以该公式.有关更多信息，请参阅此页面:

Images in scikit-image are converted to the range [0, 1] when they are converted to floating point (ie non-integer) types. So the pipeline in rgb2gray is to first divide by 255, then multiply by that formula. For more information, see this page:

https://scikit-image.org/docs/dev/user_guide/data_types.html

这篇关于关于imread和rgb2gray的数组值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！