How to convert hsv to rgb in python?

Question

I don't know why, but it doesn't work.

I've tried the following code:

matplotlib.colors.hsv_to_rgb([[[220 / 255, 255 / 255, 255 / 255]]])

matplotlib.colors.hsv_to_rgb([[[(220 % 360) / 255, 255 / 255, 255 / 255]]])

matplotlib.colors.hsv_to_rgb([[[220, 255, 255]]])

# same with
cv2.cvtColor(np.uint8([[[120, 255, 255]]]), cv2.COLOR_HSV2RGB)

but when I plot it:

import matplotlib.pyplot as plt
plt.imshow(converted_color)
plt.show()

It's showing some random stuff

getting values from GIMP:

final result

h, s, v = 270, 100, 100
r, g, b = np.multiply((colorsys.hsv_to_rgb(h/360, s/100, v/100)), 255)
crop[mask == 0] = [r, g, b]

ex e len t!

here is fixed cv2 solution. h - having 180 maximum. opencv as usual doing thing on his own way... -___-

h, s, v = 270, 100, 100
r, g, b = cv2.cvtColor(np.uint8([[[h / 2, (s/100)*255, (v/100)*255]]]), cv2.COLOR_HSV2RGB)[0][0]
crop[mask == 0] = [r, g, b]

why 3 consecutive `[` ? The function expect an array-like object, so one is enough, and probably less confusing to matplotlib, about your intensions. It seems it doesn't matter. In any casem the second example: just divide by 360. The third: values should be in range 0 to 1 — Giacomo Catenazzi, Jul 24 '20 at 07:21

Mateo Lara · Accepted Answer · 2020-07-24T07:28:03.460

1

Try using colorsys:

import colorsys
colorsys.hsv_to_rgb(0.5, 0.5, 0.4)

Output:

(0.2, 0.4, 0.4)

Edit

An example could be:

import matplotlib
import matplotlib.pyplot as plt
import colorsys

h, s, v = 0.83, 1.0, 0.50
#RGB from 0 to 1 NO from 0 to 255
r, g, b = colorsys.hsv_to_rgb(h, s, v)
print(r, g, b)

rect1 = matplotlib.patches.Rectangle((-200, -100), 400, 200, color=[r, g, b])
plt.axes().add_patch(rect1)
plt.show()

To see why you may be having troubles in displaying color using imshow refer to: Printing one color using imshow

edited Jul 24 '20 at 07:28

answered Jul 24 '20 at 05:14

Mateo Lara

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Purple in hsv is (0.83, 1.0, 0.50) and in rgb is (0.50, 0.0, 0.50) @Oleg – Mateo Lara Jul 24 '20 at 06:19
For RGB in "255 format" just multiply by 255 -> (128, 0, 128) @Oleg – Mateo Lara Jul 24 '20 at 06:43
awesome! r, g, b = np.multiply((colorsys.hsv_to_rgb(h, s, v)), 255) - just one more thing - is there way to change input range from 0-1 to 0-360 ? – Yu Da Chi Jul 24 '20 at 07:42
1

Multiplying with 360? It is just scaling. Note: most programs requires angles from 0 to 1 – Giacomo Catenazzi Jul 24 '20 at 07:46
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dividing right!! fiiiinaaalllyyy oh gooood, it was extremely hard, thank you @MateoLara – Yu Da Chi Jul 24 '20 at 07:57
1

and @Giacomo Catenazzi – Yu Da Chi Jul 24 '20 at 07:57

How to convert hsv to rgb in python?

1 Answers1