【2010-12-16】基於GDI+的水印添加工具

這個是早之前寫下的一個程序，一直沒有整理，今天整理一下。

這裏主要把水印分爲兩種：字符和圖片。而GDI+都有相關的處理函數，可以說整個過程都是GDI+在幫你完成（其實GDI+可以幫你做很多事情），相關圖片就不放這裏了，QQ博客上有：http://user.qzone.qq.com/83172527/infocenter

這邊主要是上代碼：

private Boolean DoStrWMark( ref Bitmap BeasImg, C_WMarkInfo WMarkInfo,Boolean IsShow) { if (WMarkInfo.WMarkType != WMarkType.WM_Str) { return false; } Bitmap iBeasImg = new Bitmap(BeasImg.Width, BeasImg.Height, PixelFormat.Format24bppRgb); Graphics iBeasGr = Graphics.FromImage(iBeasImg); iBeasGr.SmoothingMode = SmoothingMode.AntiAlias; iBeasGr.InterpolationMode = InterpolationMode.HighQualityBicubic; iBeasGr.DrawImage(BeasImg, new Rectangle(0, 0, BeasImg.Width, BeasImg.Height)); Int32 iOriginX = 0, iOriginY = 0; if (WMarkInfo.Rotation) { GetOrigin(WMarkInfo.WMarkLocation, BeasImg.Width, BeasImg.Height, ref iOriginX, ref iOriginY); iBeasGr.TranslateTransform((float)iOriginX, (float)iOriginY); iBeasGr.RotateTransform(WMarkInfo.RotationValue); } StringFormat iStrFormat = new StringFormat(); iStrFormat.Alignment = StringAlignment.Center; GraphicsPath iStrStroke = new GraphicsPath(); iStrStroke.AddString(WMarkInfo.WMarkStr, WMarkInfo.WMarkStrFont.FontFamily, (Int32)WMarkInfo.WMarkStrFont.Style , WMarkInfo.WMarkStrFont.SizeInPoints, new Point(0, 0), iStrFormat); RectangleF iStrSize = iStrStroke.GetBounds(); float iWmX = 0.00f; float iWmY = 0.00f; GetLocation(WMarkInfo.WMarkLocation, iStrSize, (float)BeasImg.Width, (float)BeasImg.Height, iOriginX, iOriginY, ref iWmX, ref iWmY); iStrStroke.Reset(); iStrStroke.AddString(WMarkInfo.WMarkStr, WMarkInfo.WMarkStrFont.FontFamily, (Int32)WMarkInfo.WMarkStrFont.Style , WMarkInfo.WMarkStrFont.SizeInPoints, new Point((Int32)iWmX, (Int32)iWmY), iStrFormat); if (WMarkInfo.WMarkShadow) { GraphicsPath iStrShadow = new GraphicsPath(); iStrShadow.AddString(WMarkInfo.WMarkStr, WMarkInfo.WMarkStrFont.FontFamily, (Int32)WMarkInfo.WMarkStrFont.Style , WMarkInfo.WMarkStrFont.SizeInPoints, new Point((Int32)iWmX + 2, (Int32)iWmY + 2), iStrFormat); if (WMarkInfo.WMStrEntity) { SolidBrush iStrSbShadow; if (WMarkInfo.Transparent) { iStrSbShadow = new SolidBrush(Color.FromArgb(WMarkInfo.TransparentValue, 0, 0, 0)); } else { iStrSbShadow = new SolidBrush(Color.FromArgb(255, 0, 0, 0)); } iBeasGr.FillPath(iStrSbShadow, iStrShadow); } else { Int32 iPenShadowTransparentValue = 60; if (WMarkInfo.Transparent) { iPenShadowTransparentValue = (Int32)((Double)iPenShadowTransparentValue * ((Double)WMarkInfo.TransparentValue / 255)); } for (Int32 i = 1; i < 8; i++) { Pen iStrShadowePen = new Pen(Color.FromArgb(iPenShadowTransparentValue, 0, 0, 0)); iStrShadowePen.LineJoin = LineJoin.Round; iBeasGr.DrawPath(iStrShadowePen, iStrShadow); iStrShadowePen.Dispose(); } } iStrShadow.Dispose(); } if (WMarkInfo.WMStrStroke) { Int32 iPenTransparentValue = 80; if (WMarkInfo.Transparent) { iPenTransparentValue = (Int32)((Double)iPenTransparentValue * ((Double)WMarkInfo.TransparentValue / 255)); } for (Int32 i = 1; i < 8; i++) { Pen iStrStrokePen = new Pen(Color.FromArgb(iPenTransparentValue, WMarkInfo.WMStrStrokeColo)); iStrStrokePen.LineJoin = LineJoin.Round; iBeasGr.DrawPath(iStrStrokePen, iStrStroke); iStrStrokePen.Dispose(); } } if (WMarkInfo.WMStrEntity) { SolidBrush iStrSbFront; if (WMarkInfo.Transparent) { iStrSbFront = new SolidBrush(Color.FromArgb(WMarkInfo.TransparentValue, WMarkInfo.WMarkStrColor)); } else { iStrSbFront = new SolidBrush(Color.FromArgb(255, WMarkInfo.WMarkStrColor)); } iBeasGr.FillPath(iStrSbFront, iStrStroke); iStrSbFront.Dispose(); } if (IsShow) { if (picB_Img.Image != null) { picB_Img.Image.Dispose(); picB_Img.Image = null; } picB_Img.Image = (Image)iBeasImg; } BeasImg = iBeasImg; iStrStroke.Dispose(); iBeasGr.Dispose(); return true; } 

 

以上是字符水印的方法，用過GDI+的應該可以看出這裏沒有直接用DrawString方法，其實這個畫字符的首選，感覺用這個畫字符，即使不做其他設置，字符也會平滑好看很多，但是水印中的描邊功能一直不好解決，因爲描邊在GDI+中其實就是用DrawPath畫輪廓，但是用DrawPath所畫的字體輪廓與DrawString所畫的字體實體大小有差距，這個不知道爲什麼，或許是我沒有處理好。所以這裏我所使用的是DrawPath+FillPath來畫字符，這裏畫字符有一個更好的參考例子：http://www.codeproject.com/script/Articles/ArticleVersion.aspx?aid=42529&av=17207

 

 

private Boolean DoImgWMark(ref Bitmap BeasImg, C_WMarkInfo WMarkInfo, Boolean IsShow) { if (WMarkInfo.WMarkType != WMarkType.WM_Img) { return false; } if (System.IO.File.Exists(WMarkInfo.ImgPath) == false) { return false; } Image iWMarkImg = Image.FromFile(WMarkInfo.ImgPath); Bitmap iBeasImg = new Bitmap(BeasImg.Width, BeasImg.Height, PixelFormat.Format24bppRgb); //iBeasImg.SetResolution(BeasImg.HorizontalResolution, BeasImg.VerticalResolution); Graphics iBeasGr = Graphics.FromImage(iBeasImg); iBeasGr.SmoothingMode = SmoothingMode.AntiAlias; iBeasGr.InterpolationMode = InterpolationMode.HighQualityBicubic; iBeasGr.DrawImage(BeasImg, new Rectangle(0, 0, BeasImg.Width, BeasImg.Height)); Size iImgSize = new Size(); switch (WMarkInfo.ImgSizeMode) { case WMarkImageSizeMode.AutoSize: Int32 iWmImgWidth, iWmImgHeight; if (iWMarkImg.Width > (BeasImg.Width / 4)) { iWmImgWidth = BeasImg.Width / 4; } else { iWmImgWidth = iWMarkImg.Width; } if (iWMarkImg.Height > BeasImg.Height / 4) { iWmImgHeight = BeasImg.Height / 4; } else { iWmImgHeight = iWMarkImg.Height; } iImgSize = new Size(iWmImgWidth, iWmImgHeight); break; case WMarkImageSizeMode.OriginalSize: iImgSize = new Size(iWMarkImg.Width, iWMarkImg.Height); break; } Int32 iWmX = 0; Int32 iWmY = 0; GetLocationWmImg(WMarkInfo.WMarkLocation, iImgSize, BeasImg.Width, BeasImg.Height, ref iWmX, ref iWmY); ImageAttributes iImageAttributesToBack = new ImageAttributes(); //iImageAttributesToBack.SetThreshold(0.35f, ColorAdjustType.Bitmap); ColorMap iColorMapToBack = new ColorMap(); iColorMapToBack.OldColor = Color.FromArgb(255, 255, 255, 255); iColorMapToBack.NewColor = Color.FromArgb(0, 0, 0, 0); ColorMap[] iColorMapsToBack = { iColorMapToBack }; iImageAttributesToBack.SetRemapTable(iColorMapsToBack, ColorAdjustType.Bitmap); // 設置第4行、第4列的值爲0.3來不透明度的級別 float iTransparentValue = 0.0f; if (WMarkInfo.Transparent) { iTransparentValue = (float) (Math.Round((Double) WMarkInfo.TransparentValue / 255, 1)); } else { iTransparentValue = 1.0f; } float[][] iColorMatrixElements = { new float[] {1.0f, 0.0f, 0.0f, 0.0f, 0.0f}, new float[] {0.0f, 1.0f, 0.0f, 0.0f, 0.0f}, new float[] {0.0f, 0.0f, 1.0f, 0.0f, 0.0f}, new float[] {0.0f, 0.0f, 0.0f, iTransparentValue, 0.0f}, new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f} }; ColorMatrix iColorMartix = new ColorMatrix(iColorMatrixElements); iImageAttributesToBack.SetColorMatrix(iColorMartix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap); iBeasGr.DrawImage(iWMarkImg, new Rectangle(iWmX, iWmY, iImgSize.Width, iImgSize.Height) , 0, 0, iWMarkImg.Width, iWMarkImg.Height, GraphicsUnit.Pixel, iImageAttributesToBack); if (IsShow) { if (picB_Img.Image != null) { picB_Img.Image.Dispose(); picB_Img.Image = null; } picB_Img.Image = (Image)iBeasImg; } BeasImg = iBeasImg; iBeasGr.Dispose(); iWMarkImg.Dispose(); iImageAttributesToBack.Dispose(); return true; } 

 

以上是畫圖片水印的方法，圖片就沒什麼的都是用DrawImage，這裏我沒有研究要怎麼處理比較好，比如說用輕鬆水印做的圖片水印，透明背景色它可以做得很圓滑的，估計是畫的時候做過特殊的處理的，但是我這邊沒有做了。

 

項目源碼：http://download.csdn.net/source/2912277

注：這裏我只是實現水印基本功能，所以代碼結構和本身都沒有怎麼優化。