调色板提取

复制from PIL import Image
import numpy as np
from sklearn.cluster import KMeans

# 加载图片并降采样（加速聚类）
img = Image.open("photo.jpg").resize((150, 150))
pixels = np.array(img).reshape(-1, 3)

# KMeans 提取 5 种主色
kmeans = KMeans(n_clusters=5, random_state=0, n_init='auto').fit(pixels)
colors = kmeans.cluster_centers_.astype(int)

# 按出现频率排序
counts = np.bincount(kmeans.labels_)
sorted_idx = np.argsort(-counts)

print("主色 (R,G,B)：")
for i in sorted_idx:
    r, g, b = colors[i]
    print(f"  #{r:02x}{g:02x}{b:02x}  ({r},{g},{b})")

复制package main

import (
	"fmt"
	"image"
	_ "image/jpeg"
	"os"
	"sort"
)

func main() {
	f, _ := os.Open("photo.jpg")
	defer f.Close()
	img, _, _ := image.Decode(f)
	bounds := img.Bounds()

	// 统计所有像素颜色出现次数
	colorCount := make(map[[3]uint8]int)
	for y := bounds.Min.Y; y < bounds.Max.Y; y += 2 { // 隔行采样加速
		for x := bounds.Min.X; x < bounds.Max.X; x += 2 {
			r, g, b, _ := img.At(x, y).RGBA()
			key := [3]uint8{uint8(r >> 8), uint8(g >> 8), uint8(b >> 8)}
			colorCount[key]++
		}
	}

	// 按频率排序取前 5
	type kv struct {
		k [3]uint8
		v int
	}
	var sorted []kv
	for k, v := range colorCount {
		sorted = append(sorted, kv{k, v})
	}
	sort.Slice(sorted, func(i, j int) bool { return sorted[i].v > sorted[j].v })

	fmt.Println("主色 (R,G,B)：")
	for i := 0; i < 5 && i < len(sorted); i++ {
		r, g, b := sorted[i].k[0], sorted[i].k[1], sorted[i].k[2]
		fmt.Printf("  #%02x%02x%02x  (%d,%d,%d)\n", r, g, b, r, g, b)
	}
}

复制const { createCanvas, loadImage } = require('canvas');

async function extractPalette(imagePath, n = 5) {
  const img = await loadImage(imagePath);
  const canvas = createCanvas(150, 150);
  const ctx = canvas.getContext('2d');
  ctx.drawImage(img, 0, 0, 150, 150);

  const data = ctx.getImageData(0, 0, 150, 150).data;
  const colorMap = new Map();

  // 统计每个像素颜色
  for (let i = 0; i < data.length; i += 16) { // 每 4 像素采样一次
    const r = data[i], g = data[i+1], b = data[i+2];
    const key = `${r},${g},${b}`;
    colorMap.set(key, (colorMap.get(key) || 0) + 1);
  }

  // 按频率排序
  const sorted = [...colorMap.entries()]
    .sort((a, b) => b[1] - a[1])
    .slice(0, n);

  console.log('主色 (R,G,B)：');
  sorted.forEach(([key]) => {
    const [r, g, b] = key.split(',');
    console.log(`  #${(+r).toString(16).padStart(2,'0')}${(+g).toString(16).padStart(2,'0')}${(+b).toString(16).padStart(2,'0')}  (${r},${g},${b})`);
  });
}

extractPalette('photo.jpg').catch(console.error);