🖍️ 图片颜色简化（减少颜色数）Simplify Image Colors (Reduce Colors)

使用说明与常见问题How-to & FAQ

「图片颜色简化（减少颜色数）」是什么？What is the Simplify Image Colors (Reduce Colors) tool?

把图片减少到指定数量的颜色（2–256 种）：用中位切分加 K 均值聚类挑出最有代表性的颜色，可选抖动让渐变更平滑，并列出最终调色板的色值。适合做像素风、海报风、刺绣/拼豆底稿、减小 PNG 体积，支持批量，图片只在浏览器本地处理。Reduce an image to a set number of colours (2–256). The most representative colours are chosen with median cut refined by k-means, optional dithering keeps gradients smooth, and the final palette is listed with its hex codes. Great for pixel-art and poster looks, embroidery or bead patterns and smaller PNGs. Works in bulk, locally in your browser.

如何使用「图片颜色简化（减少颜色数）」？How do I use the Simplify Image Colors (Reduce Colors) tool?

在「图片颜色简化（减少颜色数）」中，选择或拖入文件，按需设置「颜色数」、「输出格式」等选项，然后点击每个结果旁的「下载」按钮即可；有多个文件时也可以点「全部下载（ZIP）」一次打包下载。In the Simplify Image Colors (Reduce Colors): Choose or drop your files, set "Colours", "Format", then click the Download button next to each result (with several files, "Download all (ZIP)" saves them together).

颜色是怎么挑出来的？How are the colours chosen?

先统计图片里所有颜色的分布，用“中位切分”把颜色空间反复一分为二，每次切分误差最大的那一组，直到得到所需数量；再用 K 均值聚类迭代微调，使每种颜色尽量接近它代表的那批像素的平均色。计算距离时绿色权重最高、蓝色最低，更接近人眼感觉。如果原图本来就不超过所选数量的颜色，会原样保留。All the colours in the image are counted, then median cut repeatedly splits the group with the largest error in two until there are as many groups as you asked for; k-means then fine-tunes them so each colour is as close as possible to the average of the pixels it stands for. Distances weight green most and blue least, which is closer to how we see colour. If the image already has no more colours than you chose, it is left as it is.

要不要开抖动？Should I turn on dithering?

照片和渐变颜色很少时会出现明显的色带，开启抖动（Floyd–Steinberg 误差扩散）会用相邻像素的颜色交错来模拟中间色，看起来更平滑，但近看是细小的颗粒点；做像素画、平面海报、拼豆或刺绣底稿时建议关闭，色块更干净。With few colours, photos and gradients show visible banding. Dithering (Floyd–Steinberg error diffusion) mixes neighbouring pixels to suggest the in-between colours, so it looks smoother but has fine grain up close. Leave it off for pixel art, flat posters and bead or embroidery patterns, where clean blocks of colour are better.

透明背景会怎样？能减小文件吗？What about transparency, and will files get smaller?

完全透明的像素保持透明，不参与选色；半透明像素的透明度保持不变，只简化颜色。颜色越少，PNG 通常压缩得越小，适合图标和插画；照片减色后也会变小，但画质损失明显。Fully transparent pixels stay transparent and are ignored when choosing colours; semi-transparent pixels keep their transparency and only their colour is simplified. Fewer colours usually make a PNG compress smaller, which suits icons and illustrations; photos also shrink, but the loss of quality is obvious.

有哪些选项可以调整？What options can I adjust?

「图片颜色简化（减少颜色数）」的设置：「颜色数」可选 2、3、4、6、8、12等（默认 16）；「输出格式」可选 PNG、JPG、WebP（默认 PNG）；「质量」默认 92，范围 40–100；可勾选：「抖动（渐变更平滑）」；可选文件：常见图片格式（含 HEIC、HEIF、AVIF、WEBP、BMP、JFIF）。改动任一选项后结果会按新设置重新生成。Settings in the Simplify Image Colors (Reduce Colors) — "Colours": 2, 3, 4, 6, 8, 12, etc. (default 16); "Format": PNG, JPG, WebP (default PNG); "Quality" default 92, range 40–100; tick boxes: "Dithering (smoother gradients)"; files: common image formats (including HEIC, HEIF, AVIF, WEBP, BMP, JFIF). Changing any option regenerates the result with the new setting.

图片会被上传到服务器吗？Are my images uploaded?

不会。「图片颜色简化（减少颜色数）」使用浏览器 Canvas 在本地处理图片，处理后的文件直接从你的浏览器下载。No. The Simplify Image Colors (Reduce Colors) processes images locally with the browser Canvas API and the result downloads straight from your browser.

「图片颜色简化（减少颜色数）」免费吗？需要注册吗？Is the Simplify Image Colors (Reduce Colors) free? Do I need an account?

「图片颜色简化（减少颜色数）」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Simplify Image Colors (Reduce Colors) is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.