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Questions tagged [hsv]

HSV is cylindrical color space that determines colors by hue (0°-360°), saturation (percentage of white) and value (percentage of black).

468 questions
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How to compare two colors for similarity/difference

I want to design a program that can help me assess between 5 pre-defined colors which one is more similar to a variable color, and with what percentage. The thing is that I don't know how to do that manually step by step. So it is even more…
Ana Fernandes
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Choosing the correct upper and lower HSV boundaries for color detection with`cv::inRange` (OpenCV)

I have an image of a coffee can with an orange lid position of which I want to find. Here is it . gcolor2 utility shows HSV at the center of the lid to be (22, 59, 100). The question is how to choose the limits of the color then? I tried min = (18,…
Student FourK
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How to Convert RGB Color to HSV?

How can I convert a RGB Color to HSV using C#? I've searched for a fast method without using any external library.
Tom Smykowski
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HSB vs HSL vs HSV

I am making a Color class as a part of a very basic graphics API in c++. So I decided to take a look at Microsoft's .NET framework and noticed that their Color class has functions for HSB. Then I started a research to determine whether I should…
Giwrgos Tsopanoglou
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Javascript convert HSB/HSV color to RGB accurately

I need to accurately convert HSB to RGB but I am not sure how to get around the problem of turning decimals into whole numbers without rounding. This is the current function I have out of a colorpicker library: HSBToRGB = function (hsb) { var…
that_guy
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HSV to RGB Color Conversion

Is there a way to convert HSV color arguments to RGB type color arguments using pygame modules in python? I tried the following code, but it returns ridiculous values. import colorsys test_color = colorsys.hsv_to_rgb(359, 100,…
AvZ
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Finding red color in image using Python & OpenCV

I am trying to extract red color from an image. I have code that applies threshold to leave only values from specified range: img=cv2.imread('img.bmp') img_hsv=cv2.cvtColor(img, cv2.COLOR_BGR2HSV) lower_red = np.array([0,50,50]) #example…
yolo77
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Tracking white color using python opencv

I would like to track white color using webcam and python opencv. I already have the code to track blue color. _, frame = cap.read() hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV) # define range of blue color in HSV lower_blue =…
user3429616
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From RGB to HSV in OpenGL GLSL

I need to pass from RGB color space to HSV .. I searched in internet and found two different implementations, but those give me different results: A: precision mediump float; vec3 rgb2hsv(float r, float g, float b) { float h = 0.0; float…
BQuadra
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Why is the range of hue 0-180° in opencv

Can anybody explain to me why the hue value of an HSV image in OpenCV only goes to 180° and not the full 360°? I have found somewhere that OpenCV uses a 180° cylinder, but I can not really visualize such a cylinder. Thanks in advance! J
JasperV
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How to change hue of a texture with GLSL?

Is there a way to efficiently change hue of a 2D OpenGL texture using GLSL (fragment shader)? Do someone have some code for it? UPDATE: This is the code resulting from user1118321 suggestion: uniform sampler2DRect texture; const mat3 rgb2yiq =…
Andrea3000
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RGB to HSV in PHP

In PHP, what is the most straightforward way to convert a RGB triplet to HSV values?
Alix Axel
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Why does greyscale work the way it does?

My original question I read that to convert a RGB pixel into greyscale RGB, one should use r_new = g_new = b_new = r_old * 0.3 + g_old * 0.59 + b_old * 0.11 I also read, and understand, that g has a higher weighting because the human eye is more…
Delan Azabani
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Convert RGB value to HSV

I've found a method on the Internet to convert RGB values to HSV values. Unfortunately, when the values are R=G=B, I'm getting a NaN, because of the 0/0 operation. Do you know if there is an implemented method for this conversion in Java, or what do…
marionmaiden
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Sorting a list of RGB triplets into a spectrum

I have a list of RGB triplets, and I'd like to plot them in such a way that they form something like a spectrum. I've converted them to HSV, which people seem to recommend. from PIL import Image, ImageDraw import colorsys def…
Jason Sundram
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