From 487a4d5c05de08753fd1605d7b38423011e7f569 Mon Sep 17 00:00:00 2001 From: sinvo Date: Thu, 19 Mar 2026 17:17:28 +0800 Subject: [PATCH] =?UTF-8?q?=E4=BF=AE=E5=A4=8D=E5=A4=A7=E7=89=87=E5=BA=95?= =?UTF-8?q?=E8=89=B2=EF=BC=9A=E5=8A=A0=E5=A4=A7=E5=BD=A2=E6=80=81=E5=AD=A6?= =?UTF-8?q?=E9=97=AD=E8=BF=90=E7=AE=97=E7=AD=89=E6=95=88=E6=A0=B8=E5=B0=BA?= =?UTF-8?q?=E5=AF=B8?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 单次小核(图像/25)闭运算不够大，文字密集区域背景估计被文字 拉低产生灰色底色。改为41x41核多次迭代(3-N次)，等效核尺寸 远大于文字行间距，确保背景估计不被文字污染。 后续高斯模糊也加大消除块状伪影。 Co-Authored-By: Claude Opus 4.6 --- CamScanner.cs | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/CamScanner.cs b/CamScanner.cs index 5fb7085..de0ca89 100644 --- a/CamScanner.cs +++ b/CamScanner.cs @@ -332,22 +332,24 @@ public static class DocumentScanner Cv2.CvtColor(src, gray, ColorConversionCodes.BGR2GRAY); // --- b: 背景估计（形态学闭运算）--- - // 闭运算 = 先膨胀后腐蚀，效果是填平暗区域（文字），保留亮区域（背景） - // 比高斯模糊更好：不会把远处的亮区域扩散到阴影处 - int morphSize = Math.Max(gray.Width, gray.Height) / 25; - if (morphSize < 25) morphSize = 25; - if (morphSize % 2 == 0) morphSize++; + // 闭运算 = 先膨胀后腐蚀，填平暗区域（文字），保留亮区域（背景） + // 核要足够大，能完全覆盖文字笔画和行间距，否则文字密集区域背景被拉低 + // 用多次迭代小核代替单次超大核（性能更好） + int morphSize = 41; + int iterations = Math.Max(gray.Width, gray.Height) / 200; + if (iterations < 3) iterations = 3; Mat morphKernel = Cv2.GetStructuringElement(MorphShapes.Ellipse, new OpenCvSharp.Size(morphSize, morphSize)); Mat background = new Mat(); - Cv2.MorphologyEx(gray, background, MorphTypes.Close, morphKernel); + Cv2.MorphologyEx(gray, background, MorphTypes.Close, morphKernel, + null, iterations); morphKernel.Dispose(); - // 对背景估计做轻度模糊，消除形态学的块状伪影 - int smoothSize = morphSize / 2; + // 对背景估计做模糊，消除形态学的块状伪影 + int smoothSize = morphSize * iterations / 2; if (smoothSize % 2 == 0) smoothSize++; - if (smoothSize < 3) smoothSize = 3; + if (smoothSize < 21) smoothSize = 21; Cv2.GaussianBlur(background, background, new OpenCvSharp.Size(smoothSize, smoothSize), 0); // --- c: 减法提取墨迹 ---