hatarist · June 30, 2023 16:45 · Jun 30, 2023
diff --git a/README.md b/README.md
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+# RGB to color name converter using Python
+
+## Dependencies
+
+Oops, I was too lazy to implement the RGB to HSL conversion myself, hence you need the [colormath](https://python-colormath.readthedocs.io/en/latest/).
+
+## Usage example
+
+```python
+get_color_name((241, 95, 188))  # 'pink'
+get_color_name((241, 0, 0))  # 'red'
+get_color_name((60, 60, 0))  # 'darkyellow'
+```
+
+### Disclaimer / License
+
+The algorithm is shamelessly taken from Microsoft PowerToys Color Picker (uses MIT license)
+
+Source: https://github.com/microsoft/PowerToys/blob/main/src/common/ManagedCommon/ColorNameHelper.cs
+
+This piece-of-poop code is published under WTFPL or whatever else license lol.
diff --git a/rgb_to_color_name.py b/rgb_to_color_name.py
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+from colormath.color_objects import sRGBColor, HSLColor
+from colormath.color_conversions import convert_color
+
+
+HUE_LIMITS_FOR_SAT = (
+    (8,  0,  0, 44,  0,  0,  0, 63,  0,   0, 122,   0, 134,   0,   0,   0,   0, 166, 176, 241,   0, 256,   0),  # Sat: 20-75
+    (0, 10,  0, 32, 46,  0,  0,  0, 61,   0, 106,   0, 136, 144,   0,   0,   0, 158, 166, 241,   0,   0, 256),  # Sat: 75-115
+    (0,  8,  0,  0, 39, 46,  0,  0,  0,  71, 120,   0, 131, 144,   0,   0, 163,   0, 177, 211, 249,   0, 256),  # Sat: 115-150
+    (0, 11, 26,  0,  0, 38, 45,  0,  0,  56, 100, 121, 129,   0, 140,   0, 180,   0,   0, 224, 241,   0, 256),  # Sat: 150-240
+    (0, 13, 27,  0,  0, 36, 45,  0,  0,  59, 118,   0, 127, 136, 142,   0, 185,   0,   0, 216, 239,   0, 256),  # Sat: 240-255
+)
+
+LUM_LIMITS_FOR_HUE = (
+    (130, 100, 115, 100, 100, 100, 110,  75, 100,  90, 100, 100, 100, 100,  80, 100, 100, 100, 100, 100, 100, 100, 100),
+    (170, 170, 170, 155, 170, 170, 170, 170, 170, 115, 170, 170, 170, 170, 170, 170, 170, 170, 150, 150, 170, 140, 165)
+)
+
+
+COLOR_NAMES = (
+    # light
+    ("coral", "rose", "lightorange", "tan", "tan", "lightyellow", "lightyellow", "tan", "lightgreen", "lime", "lightgreen", "lightgreen", "aqua", "skyblue", "lightturquoise", "paleblue", "lightblue", "iceblue", "periwinkle", "lavender", "pink", "tan", "rose"),
+
+    # mid
+    ("coral", "red", "orange", "brown", "tan", "gold", "yellow", "olivegreen", "olivegreen", "green", "green", "brightgreen", "teal", "aqua", "turquoise", "paleblue", "blue", "bluegray", "indigo", "purple", "pink", "brown", "red"),
+
+    # dark
+    ("brown", "darkred", "brown", "brown", "brown", "darkyellow", "darkyellow", "brown", "darkgreen", "darkgreen", "darkgreen", "darkgreen", "darkteal", "darkteal", "darkteal", "darkblue", "darkblue", "bluegray", "indigo", "darkpurple", "plum", "brown", "darkred"),
+)
+
+
+def rgb_to_hsl(r, g, b):
+    rgb = sRGBColor(r, g, b, is_upscaled=True)
+    hsl = convert_color(rgb, HSLColor, target_illuminant='d50')
+    return hsl.get_value_tuple()
+
+
+def get_color_name(rgb):
+    hsl = rgb_to_hsl(*rgb)
+    hue, sat, lum = hsl
+
+    hue = (0 if hue == 0 else hue / 360) * 255  # using normalization to 0-255 instead of 0-360°
+    sat = sat * 255
+    lum = lum * 255
+
+    if lum > 240:
+        return "white"
+    elif lum < 20:
+        return "black"
+
+    if sat <= 20:
+        if (lum > 170):
+            return "lightgray"
+        elif (lum > 100):
+            return "gray"
+        else:
+            return "darkgray"
+
+    if (sat > 20 and sat <= 75):
+        pHueLimits = HUE_LIMITS_FOR_SAT[0]
+    elif (sat > 75 and sat <= 115):
+        pHueLimits = HUE_LIMITS_FOR_SAT[1]
+    elif (sat > 115 and sat <= 150):
+        pHueLimits = HUE_LIMITS_FOR_SAT[2]
+    elif (sat > 150 and sat <= 240):
+        pHueLimits = HUE_LIMITS_FOR_SAT[3]
+    else:
+        pHueLimits = HUE_LIMITS_FOR_SAT[4]
+
+    colorIndex = -1
+    for i in range(0, len(COLOR_NAMES[1])):
+        if hue < pHueLimits[i]:
+            colorIndex = i
+            break
+
+    if colorIndex != -1:
+        if (lum > LUM_LIMITS_FOR_HUE[1][colorIndex]):
+            return COLOR_NAMES[0][colorIndex]  # light
+        elif (lum < LUM_LIMITS_FOR_HUE[0][colorIndex]):
+            return COLOR_NAMES[2][colorIndex]  # dark
+        else:
+            return COLOR_NAMES[1][colorIndex]  # mid
+
+    return ''
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