🌫️ 位图模糊（BMP 高斯模糊 / 方框模糊）Blur a Bitmap (Gaussian & Box Blur)
给位图（BMP）或其他图片加模糊效果：高斯模糊过渡自然，适合做背景、柔化细节；方框模糊（均值模糊）按设定半径取周围像素的平均值，计算结果可预测。半径从 0 到 50 像素可调，边缘按最近像素延伸、不会出现黑边，透明部分按预乘 Alpha 计算不会发灰。默认导出 24 位 BMP，也可以导出 PNG，支持批量，图片只在浏览器本地处理。Blur a bitmap (BMP) or any other image. Gaussian blur gives a smooth, natural softening — good for backgrounds and hiding detail — while box blur (mean blur) averages the pixels within the radius for a predictable result. Choose a radius from 0 to 50 pixels; edges are extended from the nearest pixel so no dark border appears, and transparency is handled with premultiplied alpha so edges do not go grey. The result is a 24-bit BMP by default, or PNG; works in bulk, and images are processed locally in your browser.
使用说明与常见问题How-to & FAQ
「位图模糊（BMP 高斯模糊 / 方框模糊）」是什么？What is the Blur a Bitmap (Gaussian & Box Blur) tool?
给位图（BMP）或其他图片加模糊效果：高斯模糊过渡自然，适合做背景、柔化细节；方框模糊（均值模糊）按设定半径取周围像素的平均值，计算结果可预测。半径从 0 到 50 像素可调，边缘按最近像素延伸、不会出现黑边，透明部分按预乘 Alpha 计算不会发灰。默认导出 24 位 BMP，也可以导出 PNG，支持批量，图片只在浏览器本地处理。Blur a bitmap (BMP) or any other image. Gaussian blur gives a smooth, natural softening — good for backgrounds and hiding detail — while box blur (mean blur) averages the pixels within the radius for a predictable result. Choose a radius from 0 to 50 pixels; edges are extended from the nearest pixel so no dark border appears, and transparency is handled with premultiplied alpha so edges do not go grey. The result is a 24-bit BMP by default, or PNG; works in bulk, and images are processed locally in your browser.
如何使用「位图模糊（BMP 高斯模糊 / 方框模糊）」？How do I use the Blur a Bitmap (Gaussian & Box Blur) tool?
在「位图模糊（BMP 高斯模糊 / 方框模糊）」中，选择或拖入文件，按需设置「模糊半径」、「方式」、「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 Blur a Bitmap (Gaussian & Box Blur): Choose or drop your files, set "Blur radius", "Type", "Format", then click the Download button next to each result (with several files, "Download all (ZIP)" saves them together).
高斯模糊和方框模糊有什么区别？What is the difference between Gaussian and box blur?
方框模糊把半径范围内的像素直接取平均，边界生硬、可能有方块感，但结果容易预测（例如半径 1 时，一个白点会变成 3×3 范围、亮度各为 1/9）；高斯模糊离中心越远权重越小，过渡更自然，是照片和背景虚化常用的方式。本工具的高斯模糊用三次方框模糊近似，速度快、效果与标准高斯模糊几乎一致。Box blur simply averages the pixels within the radius: edges can look blocky but the result is predictable (with radius 1 a single white dot becomes a 3×3 patch at 1/9 brightness). Gaussian blur gives pixels further from the centre less weight, for a smoother, more natural look — the usual choice for photos and backgrounds. Here it is approximated by three box blurs, which is fast and practically identical to a true Gaussian.
为什么边缘不会变黑？透明图片怎么处理？Why don't the edges go dark? What about transparent images?
图片外面没有像素，工具会按最近的边缘像素向外延伸，所以纯色图片模糊后仍是纯色，不会出现黑边或白边。带透明的图片按预乘 Alpha 计算，透明区域不会把颜色“拉灰”。导出 BMP 时由于 BMP 不支持透明，透明部分会填成白色；需要保留透明请选 PNG。There are no pixels outside the image, so the nearest edge pixel is extended outwards — a solid-colour image stays solid after blurring, with no dark or light border. Transparent images are blurred with premultiplied alpha, so transparent areas do not pull colours towards grey. BMP has no transparency, so transparent areas are filled with white in a BMP; choose PNG to keep transparency.
半径为 0 时输出和原图一样吗？Is radius 0 identical to the original?
是。半径 0 不做模糊；若输出格式与源文件相同（BMP→BMP 或 PNG→PNG），会原样复制文件字节，像素完全一致。若换了格式（例如 BMP→PNG），仍会经过画布编码，个别像素可能因色彩转换差 ±1。Yes. Radius 0 skips blurring; when the output format matches the source (BMP→BMP or PNG→PNG) the file bytes are copied unchanged so every pixel matches. If you change format (e.g. BMP→PNG) the image still goes through the canvas, so a few pixels may differ by ±1 from colour conversion.
有哪些选项可以调整？What options can I adjust?
「位图模糊（BMP 高斯模糊 / 方框模糊）」的设置：「模糊半径」默认 4，范围 0–50；「方式」可选 高斯模糊、方框模糊（均值）（默认 高斯模糊）；「输出格式」可选 BMP、PNG（默认 BMP）；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 Blur a Bitmap (Gaussian & Box Blur) — "Blur radius" default 4, range 0–50; "Type": Gaussian, Box (mean) (default Gaussian); "Format": BMP, PNG (default BMP); 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。「位图模糊（BMP 高斯模糊 / 方框模糊）」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 Blur a Bitmap (Gaussian & Box Blur) processes images locally with the browser Canvas API and the result downloads straight from your browser.
「位图模糊（BMP 高斯模糊 / 方框模糊）」免费吗？需要注册吗？Is the Blur a Bitmap (Gaussian & Box Blur) free? Do I need an account?
「位图模糊（BMP 高斯模糊 / 方框模糊）」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 Blur a Bitmap (Gaussian & Box Blur) is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.