✍️ 手写签名提取（去白底透明）Signature Extractor (Transparent Background)

使用说明与常见问题How-to & FAQ

「手写签名提取（去白底透明）」是什么？What is the Signature Extractor (Transparent Background) tool?

把纸上手写签名的照片变成透明背景的 PNG：自动去掉白纸和阴影，可调节阈值、改成黑色或蓝色墨迹、自动裁掉空白，生成的电子签名可直接放进 Word、PDF 或合同。Turn a photo of a handwritten signature into a transparent PNG: paper and shadows are removed automatically, you can tune the threshold, recolour the ink black or blue and auto-crop the margins — ready for Word, PDF or contracts.

如何使用「手写签名提取（去白底透明）」？How do I use the Signature Extractor (Transparent Background)?

在白纸上用深色笔签名，拍照或扫描后上传。工具会自动计算阈值去掉背景，如果笔画断开就调低阈值、背景残留就调高。选择墨迹颜色并勾选自动裁剪，然后下载透明 PNG。Sign on white paper with a dark pen, photograph or scan it and upload. The threshold is chosen automatically; lower it if strokes break up or raise it if background remains. Pick the ink colour, keep auto-crop on and download the transparent PNG.

怎样拍出效果最好的签名？How do I get the best result?

用黑色或深蓝色签字笔在干净的白纸上签，光线均匀、避免手机投下阴影，正对纸面拍摄并让签名占满画面大部分。工具会自动减弱阴影，但原图越干净效果越好。Sign with a black or dark-blue pen on clean white paper, use even light without phone shadows, shoot straight on and let the signature fill most of the frame. Shadows are reduced automatically, but a clean photo always works best.

电子签名有法律效力吗？Is an image signature legally binding?

签名图片本身只是图像，是否有效取决于具体场景和当地法律；正式合同建议使用依法设立的电子认证服务（可靠电子签名）。本工具只在本地处理图片，不会上传你的签名。A signature image is just a picture; whether it is binding depends on the context and local law — for formal contracts use a certified e-signature service. This tool processes everything locally and never uploads your signature.

「手写签名提取（去白底透明）」免费吗？数据会上传吗？Is the Signature Extractor (Transparent Background) free? Is my data uploaded?

「手写签名提取（去白底透明）」完全免费，无需注册或安装，手机和电脑都能用；所有处理都在你的浏览器本地完成，输入的内容和文件不会上传到服务器。The Signature Extractor (Transparent Background) is completely free with no sign-up or install and works on phones and desktops; everything runs locally in your browser and nothing you enter is uploaded.