How to detect blue color object using opencv
blob, colors, detect, opencv
Solution
For `blue`, it can be used as HSV values : `[120,255,255]`
I calculated it from `GIMP`, an open-source image processing tool like Photoshop. Similarly you can use any tools to do so.
But remember in OpenCV, Hue ranges from 0-180, S = 0-255, V = 0-255
But in GIMP, it is H = 0-360, S = 0-100, V = 0-100. So you have to apply scaling according to that.
A lot of interactive sites are available on googling. You can try that.
- To know how they convert these values, check its wikipedia page.
- Or you can check out the OpenCV docs to see how it works in OpenCV : cvtColor()
I just pasted the relation for you here:
Problem
i'm using that guide to detect blobs of a certain color. On that guide, it check for orange's blob and it use this values: ``` int orange[3] = {200, 250, 10}; ``` On the guide it says that this values represents the orange in HSV. I don't know how they calculate this values but i try to check for blue value converting from rgb to hsv but it doesn't work. What i have to detect is this color: Any ideas on how to determinate HSV values to detect colors? thanks!!