Histeq in old version worked with RGB
显示 更早的评论
Hi,
I am reusing some old code from a research project we did years ago, I used 'ImageEq=histeq(ImageOrg, counts)'
Now I noticed that histeq does not accepted RGB while it was no problem in the older version, so Did older version of Matlab accept RGB-images for the function histeq? and if yes, how did that work because it should act than on one of the three matrices ( R, G or B)?
thank for your help , regards J
1 个评论
bdcxns
2019-3-4
编辑：Image Analyst
2019-3-4
Your question has been here for several years, but I am curious about this, since there is no information on how Matlab implement the histeq on color images (in 2017a as I am using), until I tried out different possible ways.
It is actually reshape(histeq(rgbimage(:)),size(rgbimage)). For rgbimage being a colour image in rgb.
采纳的回答
Image Analyst
2012-5-13
0 个投票
If it did it, it either did it on each color channel independently, which would give color artifacts, or it converted to hsv and did it on the v channel, which would not give artifacts. However, in general, histogram equalization rarely gives nice looking images because of the non-linear mapping of the gray levels which makes the images look unnatural. Why do you think you want to use it, say, as opposed to a normal, linear contrast stretch?
更多回答（2 个）
Jürgen
2012-5-13
0 个投票
1 个评论
Image Analyst
2012-5-13
Histogram equalization is not needed at all to do extraction. It only brightens things up, but you can still threshold and extract the white objects just fine with the original image, it's just that the threshold is at a different level but the end result is identical. Unless you need it for some reason for visual purposes (or curiosity) you're just spending more time than necessary doing something that is not at all needed.
Jürgen
2012-5-14
0 个投票
2 个评论
Image Analyst
2012-5-14
It could work, but like I said it usually doesn't produce images as natural looking as if you had just done a linear contrast stretch, like you'd get with imadjust(). By the way, you should have put this as a "Comment on this Answer" rather than an original "Answer" to your question.
Jürgen
2012-5-14
类别
在 帮助中心 和 File Exchange 中查找有关 Image display and manipulation 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
