Colour picker

Read the exact colour of a single pixel — as hex, RGB and HSL.

Function

pick_colour(input, x, y) -> Colour

Language	Name
Rust	pick_colour
JavaScript	pickColour
Python	pick_colour
CLI	dusrelimage pick-colour <input> --x 120 --y 80

The Colour struct

type Colour = {
  hex: string;        // "#RRGGBB"
  r: number; g: number; b: number; a: number;  // 0–255 each
  hsl: [number, number, number];               // hue 0–360, saturation 0–1, lightness 0–1
};

Examples

import { pickColour } from 'dusrelimage';

const c = pickColour(input, 120, 80);
console.log(c.hex);  // "#3a7bd5"
console.log(c.r, c.g, c.b); // 58 123 213
console.log(c.hsl);  // [210, 0.6, 0.53]

from dusrelimage import pick_colour

c = pick_colour(data, 120, 80)
print(c["hex"], c["r"], c["g"], c["b"])

$ dusrelimage pick-colour photo.jpg --x 120 --y 80
{"hex":"#3A7BD5","r":58,"g":123,"b":213,"a":255,"hsl":[210.0,0.6,0.53]}

Out of bounds is an error, not a guess

Coordinates outside the image fail with PIXEL_OUT_OF_BOUNDS — the picker never wraps around or clamps to the edge. Coordinates are 0-based: (0, 0) is the top-left pixel.

Errors

Code	When
INVALID_IMAGE	Input is not a decodable image.
PIXEL_OUT_OF_BOUNDS	(x, y) is outside the image.
IMAGE_TOO_LARGE	Over max_pixels (default 120,000,000).
EMPTY_INPUT	Empty input bytes.