本文实例讲述了C#给图片添加水印的方法。分享给大家供大家参考，具体如下：
using System; using System.Data; using System.Configuration; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; using System.Drawing; using System.IO; using System.Drawing.Imaging; /// <summary> ///ImgWater 的摘要说明 /// </summary> public class ImgWater { public ImgWater() { // //TODO: 在此处添加构造函数逻辑 // } /// <summary> /// 图片水印 /// </summary> /// <param name="ImgFile">原图文件地址</param> /// <param name="WaterImg">水印图片地址</param> /// <param name="sImgPath">水印图片保存地址</param> /// <param name="Alpha">水印透明度设置</param> /// <param name="iScale">水印图片在原图上的显示比例</param> /// <param name="intDistance">水印图片在原图上的边距确定,以图片的右边和下边为准,当设定的边距超过一定大小后参数会自动失效</param> public bool zzsImgWater( string ImgFile , string WaterImg , string sImgPath , float Alpha , float iScale , int intDistance ) { try { //装载图片 FileStream fs = new FileStream(ImgFile, FileMode.Open); BinaryReader br = new BinaryReader(fs); byte[] bytes = br.ReadBytes((int)fs.Length); br.Close(); fs.Close(); MemoryStream ms = new MemoryStream(bytes); System.Drawing.Image imgPhoto = System.Drawing.Image.FromStream(ms); //System.Drawing.Image imgPhoto = System.Drawing.Image.FromFile(ImgFile); int imgPhotoWidth = imgPhoto.Width; int imgPhotoHeight = imgPhoto.Height; System.Drawing.Image imgWatermark = new Bitmap(WaterImg); int imgWatermarkWidth = imgWatermark.Width; int imgWatermarkHeight = imgWatermark.Height; //计算水印图片尺寸 decimal aScale = Convert.ToDecimal(iScale); decimal pScale = 0.05M; decimal MinScale = aScale - pScale; decimal MaxScale = aScale + pScale; int imgWatermarkWidthNew = imgWatermarkWidth; int imgWatermarkHeightNew = imgWatermarkHeight; if (imgPhotoWidth >= imgWatermarkWidth && imgPhotoHeight >= imgWatermarkHeight && imgPhotoWidth >= imgPhotoHeight) if (imgWatermarkWidth > imgWatermarkHeight) if ((MinScale <= Math.Round((Convert.ToDecimal(imgWatermarkWidth) / Convert.ToDecimal(imgPhotoWidth)), 7)) && (Math.Round((Convert.ToDecimal(imgWatermarkWidth) / Convert.ToDecimal(imgPhotoWidth)), 7) <= MaxScale)) { } else { imgWatermarkWidthNew = Convert.ToInt32(imgPhotoWidth * aScale); imgWatermarkHeightNew = Convert.ToInt32((imgPhotoWidth * aScale / imgWatermarkWidth) * imgWatermarkHeight); } else if ((MinScale <= Math.Round((Convert.ToDecimal(imgWatermarkHeight) / Convert.ToDecimal(imgPhotoHeight)), 7)) && (Math.Round((Convert.ToDecimal(imgWatermarkHeight) / Convert.ToDecimal(imgPhotoHeight)), 7) <= MaxScale)) { } else { imgWatermarkHeightNew = Convert.ToInt32(imgPhotoHeight * aScale); imgWatermarkWidthNew = Convert.ToInt32((imgPhotoHeight * aScale / imgWatermarkHeight) * imgWatermarkWidth); } if (imgWatermarkWidth >= imgPhotoWidth && imgWatermarkHeight >= imgPhotoHeight && imgWatermarkWidth >= imgWatermarkHeight) { imgWatermarkWidthNew = Convert.ToInt32(imgPhotoWidth * aScale); imgWatermarkHeightNew = Convert.ToInt32(((imgPhotoWidth * aScale) / imgWatermarkWidth) * imgWatermarkHeight); } if (imgWatermarkWidth >= imgPhotoWidth && imgWatermarkHeight <= imgPhotoHeight && imgPhotoWidth >= imgPhotoHeight) { imgWatermarkWidthNew = Convert.ToInt32(imgPhotoWidth * aScale); imgWatermarkHeightNew = Convert.ToInt32(((imgPhotoWidth * aScale) / imgWatermarkWidth) * imgWatermarkHeight); } if (imgWatermarkWidth <= imgPhotoWidth && imgWatermarkHeight >= imgPhotoHeight && imgPhotoWidth >= imgPhotoHeight) { imgWatermarkHeightNew = Convert.ToInt32(imgPhotoHeight * aScale); imgWatermarkWidthNew = Convert.ToInt32(((imgPhotoHeight * aScale) / imgWatermarkHeight) * imgWatermarkWidth); } if (imgPhotoWidth >= imgWatermarkWidth && imgPhotoHeight >= imgWatermarkHeight && imgPhotoWidth <= imgPhotoHeight) if (imgWatermarkWidth > imgWatermarkHeight) if ((MinScale <= Math.Round((Convert.ToDecimal(imgWatermarkWidth) / Convert.ToDecimal(imgPhotoWidth)), 7)) && (Math.Round((Convert.ToDecimal(imgWatermarkWidth) / Convert.ToDecimal(imgPhotoWidth)), 7) <= MaxScale)) { } else { imgWatermarkWidthNew = Convert.ToInt32(imgPhotoWidth * aScale); imgWatermarkHeightNew = Convert.ToInt32(((imgPhotoWidth * aScale) / imgWatermarkWidth) * imgWatermarkHeight); } else if ((MinScale <= Math.Round((Convert.ToDecimal(imgWatermarkHeight) / Convert.ToDecimal(imgPhotoHeight)), 7)) && (Math.Round((Convert.ToDecimal(imgWatermarkHeight) / Convert.ToDecimal(imgPhotoHeight)), 7) <= MaxScale)) { } else { imgWatermarkHeightNew = Convert.ToInt32(imgPhotoHeight * aScale); imgWatermarkWidthNew = Convert.ToInt32(((imgPhotoHeight * aScale) / imgWatermarkHeight) * imgWatermarkWidth); } if (imgWatermarkWidth >= imgPhotoWidth && imgWatermarkHeight >= imgPhotoHeight && imgWatermarkWidth <= imgWatermarkHeight) { imgWatermarkHeightNew = Convert.ToInt32(imgPhotoHeight * aScale); imgWatermarkWidthNew = Convert.ToInt32(((imgPhotoHeight * aScale) / imgWatermarkHeight) * imgWatermarkWidth); } if (imgWatermarkWidth >= imgPhotoWidth && imgWatermarkHeight <= imgPhotoHeight && imgPhotoWidth <= imgPhotoHeight) { imgWatermarkWidthNew = Convert.ToInt32(imgPhotoWidth * aScale); imgWatermarkHeightNew = Convert.ToInt32(((imgPhotoWidth * aScale) / imgWatermarkWidth) * imgWatermarkHeight); } if (imgWatermarkWidth <= imgPhotoWidth && imgWatermarkHeight >= imgPhotoHeight && imgPhotoWidth <= imgPhotoHeight) { imgWatermarkHeightNew = Convert.ToInt32(imgPhotoHeight * aScale); imgWatermarkWidthNew = Convert.ToInt32(((imgPhotoHeight * aScale) / imgWatermarkHeight) * imgWatermarkWidth); } //将原图画出来 Bitmap bmPhoto = new Bitmap(imgPhotoWidth, imgPhotoHeight, System.Drawing.Imaging.PixelFormat.Format24bppRgb); bmPhoto.SetResolution(72, 72); Graphics gbmPhoto = Graphics.FromImage(bmPhoto); gbmPhoto.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; gbmPhoto.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; gbmPhoto.Clear(Color.White); gbmPhoto.DrawImage( imgPhoto , new Rectangle(0, 0, imgPhotoWidth, imgPhotoHeight) , 0 , 0 , imgPhotoWidth , imgPhotoHeight , GraphicsUnit.Pixel ); Bitmap bmWatermark = new Bitmap(bmPhoto); bmWatermark.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution); Graphics gWatermark = Graphics.FromImage(bmWatermark); //指定高质量显示水印图片质量 gWatermark.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; gWatermark.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; ImageAttributes imageAttributes = new ImageAttributes(); //设置两种颜色,达到合成效果 ColorMap colorMap = new ColorMap(); colorMap.OldColor = Color.FromArgb(255, 0, 255, 0); colorMap.NewColor = Color.FromArgb(0, 0, 0, 0); ColorMap[] remapTable = { colorMap }; imageAttributes.SetRemapTable(remapTable, System.Drawing.Imaging.ColorAdjustType.Bitmap); //用矩阵设置水印图片透明度 float[][] colorMatrixElements = { 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, Alpha, 0.0f}, new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f} }; System.Drawing.Imaging.ColorMatrix wmColorMatrix = new System.Drawing.Imaging.ColorMatrix(colorMatrixElements); imageAttributes.SetColorMatrix(wmColorMatrix, System.Drawing.Imaging.ColorMatrixFlag.Default, System.Drawing.Imaging.ColorAdjustType.Bitmap); //确定水印边距 int xPos = imgPhotoWidth - imgWatermarkWidthNew; int yPos = imgPhotoHeight - imgWatermarkHeightNew; int xPosOfWm = 0; int yPosOfWm = 0; if (xPos > intDistance) xPosOfWm = xPos - intDistance; else xPosOfWm = xPos; if (yPos > intDistance) yPosOfWm = yPos - intDistance; else yPosOfWm = yPos; gWatermark.DrawImage( imgWatermark , new Rectangle(xPosOfWm, yPosOfWm, imgWatermarkWidthNew, imgWatermarkHeightNew) , 0 , 0 , imgWatermarkWidth , imgWatermarkHeight , GraphicsUnit.Pixel , imageAttributes ); imgPhoto = bmWatermark; //以jpg格式保存图片 imgPhoto.Save(sImgPath, System.Drawing.Imaging.ImageFormat.Jpeg); //销毁对象 gbmPhoto.Dispose(); gWatermark.Dispose(); imgPhoto.Dispose(); imgWatermark.Dispose(); return true; } catch { return false ; } } /**//// <summary> /// 文字水印 /// </summary> /// <param name="ImgFile">原图文件地址</param> /// <param name="TextFont">水印文字</param> /// <param name="sImgPath">文字水印图片保存地址</param> /// <param name="hScale">高度位置</param> /// <param name="widthFont">文字块在图片中所占宽度比例</param> /// <param name="Alpha">文字透明度 其数值的范围在0到255</param> public bool zzsTextWater( string ImgFile , string TextFont , string sImgPath , float hScale , float widthFont , int Alpha ) { try { FileStream fs = new FileStream(ImgFile, FileMode.Open); BinaryReader br = new BinaryReader(fs); byte[] bytes = br.ReadBytes((int)fs.Length); br.Close(); fs.Close(); MemoryStream ms = new MemoryStream(bytes); System.Drawing.Image imgPhoto = System.Drawing.Image.FromStream(ms); //System.Drawing.Image imgPhoto = System.Drawing.Image.FromFile(ImgFile); int imgPhotoWidth = imgPhoto.Width; int imgPhotoHeight = imgPhoto.Height; Bitmap bmPhoto = new Bitmap(imgPhotoWidth, imgPhotoHeight, System.Drawing.Imaging.PixelFormat.Format24bppRgb); bmPhoto.SetResolution(72, 72); Graphics gbmPhoto = Graphics.FromImage(bmPhoto); gbmPhoto.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; gbmPhoto.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; gbmPhoto.DrawImage( imgPhoto , new Rectangle(0, 0, imgPhotoWidth, imgPhotoHeight) , 0 , 0 , imgPhotoWidth , imgPhotoHeight , GraphicsUnit.Pixel ); //建立字体大小的数组,循环找出适合图片的水印字体 //int[] sizes = new int[] { 1000, 800, 700, 650, 600, 560, 540, 500, 450, 400, 380, 360, 340, 320, 300, 280, 260, 240, 220, 200, 180, 160, 140, 120, 100, 80, 72, 64, 48, 32, 28, 26, 24, 20, 28, 16, 14, 12, 10, 8, 6, 4, 2 }; int[] sizes = new int[] { 28, 26, 24, 20, 16, 14, 12 }; System.Drawing.Font crFont = null; System.Drawing.SizeF crSize = new SizeF(); for (int i = 0; i < 7; i++) { crFont = new Font("微软雅黑", sizes[i], FontStyle.Bold); crSize = gbmPhoto.MeasureString(TextFont, crFont); if ((ushort)crSize.Width < (ushort)imgPhotoWidth * widthFont) break; } //设置水印字体的位置 //int yPixlesFromBottom = (int)(imgPhotoHeight * hScale); //float yPosFromBottom = ((imgPhotoHeight - yPixlesFromBottom) - (crSize.Height / 2)); //float xCenterOfImg = (imgPhotoWidth * 1 / 2); float yPosFromBottom = imgPhotoHeight *0.85f; float xCenterOfImg = imgPhotoWidth * 0.8f; //if (xCenterOfImg<crSize.Height) // xCenterOfImg = (imgPhotoWidth * (1 - (crSize.Height)/ imgPhotoWidth)); System.Drawing.StringFormat StrFormat = new System.Drawing.StringFormat(); StrFormat.Alignment = System.Drawing.StringAlignment.Center; // System.Drawing.SolidBrush semiTransBrush2 = new System.Drawing.SolidBrush(Color.FromArgb(Alpha, 0, 0, 0)); gbmPhoto.DrawString( TextFont , crFont , semiTransBrush2 , new System.Drawing.PointF(xCenterOfImg + 1, yPosFromBottom + 1) , StrFormat ); System.Drawing.SolidBrush semiTransBrush = new System.Drawing.SolidBrush(Color.FromArgb(Alpha, 255, 255, 255)); //gbmPhoto.FillRectangle(semiTransBrush2, new RectangleF(new PointF(xCenterOfImg - crSize.Width / 2, yPosFromBottom - 4), crSize)); gbmPhoto.DrawString( TextFont , crFont , semiTransBrush , new System.Drawing.PointF(xCenterOfImg, yPosFromBottom) , StrFormat ); bmPhoto.Save(sImgPath, System.Drawing.Imaging.ImageFormat.Jpeg); gbmPhoto.Dispose(); imgPhoto.Dispose(); bmPhoto.Dispose(); return true; } catch { return false; } } /**//// <summary> /// 文字和Logo图片水印 /// </summary> /// <param name="ImgFile">原图文件地址</param> /// <param name="WaterImg">水印图片地址</param> /// <param name="TextFont">水印文字信息</param> /// <param name="sImgPath">生存水印图片后的保存地址</param> /// <param name="ImgAlpha">水印图片的透明度</param> /// <param name="imgiScale">水印图片在原图上的显示比例</param> /// <param name="intimgDistance">水印图片在原图上的边距确定,以图片的右边和下边为准,当设定的边距超过一定大小后参数会自动失效</param> /// <param name="texthScale">水印文字高度位置,从图片底部开始计算，0－1</param> /// <param name="textwidthFont">文字块在图片中所占宽度比例 0－1</param> /// <param name="textAlpha">文字透明度 其数值的范围在0到255</param> public void zzsImgTextWater( string ImgFile , string WaterImg , string TextFont , string sImgPath , float ImgAlpha , float imgiScale , int intimgDistance , float texthScale , float textwidthFont , int textAlpha ) { try { FileStream fs = new FileStream(ImgFile, FileMode.Open); BinaryReader br = new BinaryReader(fs); byte[] bytes = br.ReadBytes((int)fs.Length); br.Close(); fs.Close(); MemoryStream ms = new MemoryStream(bytes); System.Drawing.Image imgPhoto = System.Drawing.Image.FromStream(ms); //System.Drawing.Image imgPhoto = System.Drawing.Image.FromFile(ImgFile); int imgPhotoWidth = imgPhoto.Width; int imgPhotoHeight = imgPhoto.Height; Bitmap bmPhoto = new Bitmap(imgPhotoWidth, imgPhotoHeight, System.Drawing.Imaging.PixelFormat.Format24bppRgb); bmPhoto.SetResolution(72, 72); Graphics gbmPhoto = Graphics.FromImage(bmPhoto); gbmPhoto.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; gbmPhoto.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; gbmPhoto.DrawImage( imgPhoto , new Rectangle(0, 0, imgPhotoWidth, imgPhotoHeight) , 0 , 0 , imgPhotoWidth , imgPhotoHeight , GraphicsUnit.Pixel ); //建立字体大小的数组,循环找出适合图片的水印字体 int[] sizes = new int[] { 1000, 800, 700, 650, 600, 560, 540, 500, 450, 400, 380, 360, 340, 320, 300, 280, 260, 240, 220, 200, 180, 160, 140, 120, 100, 80, 72, 64, 48, 32, 28, 26, 24, 20, 28, 16, 14, 12, 10, 8, 6, 4, 2 }; System.Drawing.Font crFont = null; System.Drawing.SizeF crSize = new SizeF(); for (int i = 0; i < 43; i++) { crFont = new Font("arial", sizes[i], FontStyle.Bold); crSize = gbmPhoto.MeasureString(TextFont, crFont); if ((ushort)crSize.Width < (ushort)imgPhotoWidth * textwidthFont) break; } //设置水印字体的位置 int yPixlesFromBottom = (int)(imgPhotoHeight * texthScale); float yPosFromBottom = ((imgPhotoHeight - yPixlesFromBottom) - (crSize.Height / 2)); float xCenterOfImg = (imgPhotoWidth * 1 / 2); System.Drawing.StringFormat StrFormat = new System.Drawing.StringFormat(); StrFormat.Alignment = System.Drawing.StringAlignment.Center; // System.Drawing.SolidBrush semiTransBrush2 = new System.Drawing.SolidBrush(Color.FromArgb(textAlpha, 0, 0, 0)); gbmPhoto.DrawString( TextFont , crFont , semiTransBrush2 , new System.Drawing.PointF(xCenterOfImg + 1, yPosFromBottom + 1) , StrFormat ); System.Drawing.SolidBrush semiTransBrush = new System.Drawing.SolidBrush(Color.FromArgb(textAlpha, 255, 255, 255)); gbmPhoto.DrawString( TextFont , crFont , semiTransBrush , new System.Drawing.PointF(xCenterOfImg, yPosFromBottom) , StrFormat ); System.Drawing.Image imgWatermark = new Bitmap(WaterImg); int imgWatermarkWidth = imgWatermark.Width; int imgWatermarkHeight = imgWatermark.Height; //计算水印图片尺寸 decimal aScale = Convert.ToDecimal(imgiScale); decimal pScale = 0.05M; decimal MinScale = aScale - pScale; decimal MaxScale = aScale + pScale; int imgWatermarkWidthNew = imgWatermarkWidth; int imgWatermarkHeightNew = imgWatermarkHeight; if (imgPhotoWidth >= imgWatermarkWidth && imgPhotoHeight >= imgWatermarkHeight && imgPhotoWidth >= imgPhotoHeight) if (imgWatermarkWidth > imgWatermarkHeight) if ((MinScale <= Math.Round((Convert.ToDecimal(imgWatermarkWidth) / Convert.ToDecimal(imgPhotoWidth)), 7)) && (Math.Round((Convert.ToDecimal(imgWatermarkWidth) / Convert.ToDecimal(imgPhotoWidth)), 7) <= MaxScale)) { } else { imgWatermarkWidthNew = Convert.ToInt32(imgPhotoWidth * aScale); imgWatermarkHeightNew = Convert.ToInt32((imgPhotoWidth * aScale / imgWatermarkWidth) * imgWatermarkHeight); } else if ((MinScale <= Math.Round((Convert.ToDecimal(imgWatermarkHeight) / Convert.ToDecimal(imgPhotoHeight)), 7)) && (Math.Round((Convert.ToDecimal(imgWatermarkHeight) / Convert.ToDecimal(imgPhotoHeight)), 7) <= MaxScale)) { } else { imgWatermarkHeightNew = Convert.ToInt32(imgPhotoHeight * aScale); imgWatermarkWidthNew = Convert.ToInt32((imgPhotoHeight * aScale / imgWatermarkHeight) * imgWatermarkWidth); } if (imgWatermarkWidth >= imgPhotoWidth && imgWatermarkHeight >= imgPhotoHeight && imgWatermarkWidth >= imgWatermarkHeight) { imgWatermarkWidthNew = Convert.ToInt32(imgPhotoWidth * aScale); imgWatermarkHeightNew = Convert.ToInt32(((imgPhotoWidth * aScale) / imgWatermarkWidth) * imgWatermarkHeight); } if (imgWatermarkWidth >= imgPhotoWidth && imgWatermarkHeight <= imgPhotoHeight && imgPhotoWidth >= imgPhotoHeight) { imgWatermarkWidthNew = Convert.ToInt32(imgPhotoWidth * aScale); imgWatermarkHeightNew = Convert.ToInt32(((imgPhotoWidth * aScale) / imgWatermarkWidth) * imgWatermarkHeight); } if (imgWatermarkWidth <= imgPhotoWidth && imgWatermarkHeight >= imgPhotoHeight && imgPhotoWidth >= imgPhotoHeight) { imgWatermarkHeightNew = Convert.ToInt32(imgPhotoHeight * aScale); imgWatermarkWidthNew = Convert.ToInt32(((imgPhotoHeight * aScale) / imgWatermarkHeight) * imgWatermarkWidth); } if (imgPhotoWidth >= imgWatermarkWidth && imgPhotoHeight >= imgWatermarkHeight && imgPhotoWidth <= imgPhotoHeight) if (imgWatermarkWidth > imgWatermarkHeight) if ((MinScale <= Math.Round((Convert.ToDecimal(imgWatermarkWidth) / Convert.ToDecimal(imgPhotoWidth)), 7)) && (Math.Round((Convert.ToDecimal(imgWatermarkWidth) / Convert.ToDecimal(imgPhotoWidth)), 7) <= MaxScale)) { } else { imgWatermarkWidthNew = Convert.ToInt32(imgPhotoWidth * aScale); imgWatermarkHeightNew = Convert.ToInt32(((imgPhotoWidth * aScale) / imgWatermarkWidth) * imgWatermarkHeight); } else if ((MinScale <= Math.Round((Convert.ToDecimal(imgWatermarkHeight) / Convert.ToDecimal(imgPhotoHeight)), 7)) && (Math.Round((Convert.ToDecimal(imgWatermarkHeight) / Convert.ToDecimal(imgPhotoHeight)), 7) <= MaxScale)) { } else { imgWatermarkHeightNew = Convert.ToInt32(imgPhotoHeight * aScale); imgWatermarkWidthNew = Convert.ToInt32(((imgPhotoHeight * aScale) / imgWatermarkHeight) * imgWatermarkWidth); } if (imgWatermarkWidth >= imgPhotoWidth && imgWatermarkHeight >= imgPhotoHeight && imgWatermarkWidth <= imgWatermarkHeight) { imgWatermarkHeightNew = Convert.ToInt32(imgPhotoHeight * aScale); imgWatermarkWidthNew = Convert.ToInt32(((imgPhotoHeight * aScale) / imgWatermarkHeight) * imgWatermarkWidth); } if (imgWatermarkWidth >= imgPhotoWidth && imgWatermarkHeight <= imgPhotoHeight && imgPhotoWidth <= imgPhotoHeight) { imgWatermarkWidthNew = Convert.ToInt32(imgPhotoWidth * aScale); imgWatermarkHeightNew = Convert.ToInt32(((imgPhotoWidth * aScale) / imgWatermarkWidth) * imgWatermarkHeight); } if (imgWatermarkWidth <= imgPhotoWidth && imgWatermarkHeight >= imgPhotoHeight && imgPhotoWidth <= imgPhotoHeight) { imgWatermarkHeightNew = Convert.ToInt32(imgPhotoHeight * aScale); imgWatermarkWidthNew = Convert.ToInt32(((imgPhotoHeight * aScale) / imgWatermarkHeight) * imgWatermarkWidth); } //将原图画出来 Bitmap bmWatermark = new Bitmap(bmPhoto); bmWatermark.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution); Graphics gWatermark = Graphics.FromImage(bmWatermark); //指定高质量显示水印图片质量 gWatermark.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; gWatermark.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; System.Drawing.Imaging.ImageAttributes imageAttributes = new System.Drawing.Imaging.ImageAttributes(); //设置两种颜色,达到合成效果 System.Drawing.Imaging.ColorMap colorMap = new System.Drawing.Imaging.ColorMap(); colorMap.OldColor = Color.FromArgb(255, 0, 255, 0); colorMap.NewColor = Color.FromArgb(0, 0, 0, 0); System.Drawing.Imaging.ColorMap[] remapTable = { colorMap }; imageAttributes.SetRemapTable(remapTable, System.Drawing.Imaging.ColorAdjustType.Bitmap); //用矩阵设置水印图片透明度 float[][] colorMatrixElements = { 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, ImgAlpha, 0.0f}, new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f} }; System.Drawing.Imaging.ColorMatrix wmColorMatrix = new System.Drawing.Imaging.ColorMatrix(colorMatrixElements); imageAttributes.SetColorMatrix(wmColorMatrix, System.Drawing.Imaging.ColorMatrixFlag.Default, System.Drawing.Imaging.ColorAdjustType.Bitmap); //确定水印边距 int xPos = imgPhotoWidth - imgWatermarkWidthNew; int yPos = imgPhotoHeight - imgWatermarkHeightNew; int xPosOfWm = 0; int yPosOfWm = 0; if (xPos > intimgDistance) xPosOfWm = xPos - intimgDistance; else xPosOfWm = xPos; if (yPos > intimgDistance) yPosOfWm = yPos - intimgDistance; else yPosOfWm = yPos; gWatermark.DrawImage( imgWatermark , new Rectangle(xPosOfWm, yPosOfWm, imgWatermarkWidthNew, imgWatermarkHeightNew) , 0 , 0 , imgWatermarkWidth , imgWatermarkHeight , GraphicsUnit.Pixel , imageAttributes ); imgPhoto = bmWatermark; //以jpg格式保存图片 imgPhoto.Save(sImgPath, System.Drawing.Imaging.ImageFormat.Jpeg); //销毁对象 gbmPhoto.Dispose(); gWatermark.Dispose(); bmPhoto.Dispose(); imgPhoto.Dispose(); imgWatermark.Dispose(); } catch { } } /**//// <summary> /// 缩略图 /// </summary> /// <param name="ImgFile">原图文件地址</param> /// <param name="sImgPath">缩略图保存地址</param> /// <param name="ResizeWidth">缩略图宽度</param> /// <param name="ResizeHeight">缩略图高度</param> /// <param name="BgColor">缩略图背景颜色,注意,背景颜色只能指定KnownColor中的值,如blue,red,green等</param> public bool zzsResizeImg( string ImgFile , string sImgPath , int ResizeWidth , int ResizeHeight , string BgColor ) { try { FileStream fs = new FileStream(ImgFile, FileMode.Open); BinaryReader br = new BinaryReader(fs); byte[] bytes = br.ReadBytes((int)fs.Length); br.Close(); fs.Close(); MemoryStream ms = new MemoryStream(bytes); System.Drawing.Image imgPhoto = System.Drawing.Image.FromStream(ms); //System.Drawing.Image imgPhoto = System.Drawing.Image.FromFile(ImgFile); int imgPhotoWidth = imgPhoto.Width; int imgPhotoHeight = imgPhoto.Height; int startX = 0; int StartY = 0; int NewWidth = 0; int NewHeight = 0; if (imgPhotoWidth >= ResizeWidth && imgPhotoHeight >= ResizeHeight) { NewWidth = ResizeWidth; NewHeight = Convert.ToInt32(imgPhotoHeight * Math.Round(Convert.ToDecimal(ResizeWidth) / Convert.ToDecimal(imgPhotoWidth), 10)); startX = 0; StartY = (ResizeHeight - NewHeight) / 2; } if (ResizeWidth > imgPhotoWidth && ResizeHeight < imgPhotoHeight) { NewHeight = ResizeHeight; NewWidth = Convert.ToInt32(imgPhotoWidth * Math.Round(Convert.ToDecimal(ResizeHeight) / Convert.ToDecimal(imgPhotoHeight), 10)); startX = (ResizeWidth - NewWidth) / 2; StartY = 0; } if (ResizeWidth < imgPhotoWidth && ResizeHeight > imgPhotoHeight) { NewWidth = ResizeWidth; NewHeight = Convert.ToInt32(imgPhotoHeight * Math.Round(Convert.ToDecimal(ResizeWidth) / Convert.ToDecimal(imgPhotoWidth), 10)); startX = 0; StartY = (ResizeHeight - NewHeight) / 2; } if (imgPhotoWidth < ResizeWidth && imgPhotoHeight < ResizeHeight) { NewWidth = imgPhotoWidth; NewHeight = imgPhotoHeight; startX = (ResizeWidth - imgPhotoWidth) / 2; StartY = (ResizeHeight - imgPhotoHeight) / 2; } //计算缩放图片尺寸 Bitmap bmPhoto = new Bitmap(ResizeWidth, ResizeHeight, System.Drawing.Imaging.PixelFormat.Format24bppRgb); bmPhoto.SetResolution(72, 72); Graphics gbmPhoto = Graphics.FromImage(bmPhoto); gbmPhoto.Clear(Color.FromName(BgColor)); gbmPhoto.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; gbmPhoto.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; gbmPhoto.DrawImage( imgPhoto , new Rectangle(startX, StartY, NewWidth, NewHeight) , new Rectangle(0, 0, imgPhotoWidth, imgPhotoHeight) , GraphicsUnit.Pixel ); bmPhoto.Save(sImgPath, System.Drawing.Imaging.ImageFormat.Jpeg); imgPhoto.Dispose(); gbmPhoto.Dispose(); bmPhoto.Dispose(); ms.Close(); return true; } catch { return false; } } /**//// <summary> /// 图片剪切 /// </summary> /// <param name="ImgFile">原图文件地址</param> /// <param name="sImgPath">缩略图保存地址</param> /// <param name="PointX">剪切起始点 X坐标</param> /// <param name="PointY">剪切起始点 Y坐标</param> /// <param name="CutWidth">剪切宽度</param> /// <param name="CutHeight">剪切高度</param> public bool zzsCutImg(string ImgFile, string sImgPath, int PointX, int PointY, int CutWidth, int CutHeight) { FileStream fs = new FileStream(ImgFile, FileMode.Open); BinaryReader br = new BinaryReader(fs); try { byte[] bytes = br.ReadBytes((int)fs.Length); br.Close(); fs.Close(); MemoryStream ms = new MemoryStream(bytes); System.Drawing.Image imgPhoto = System.Drawing.Image.FromStream(ms); //System.Drawing.Image imgPhoto = System.Drawing.Image.FromFile(ImgFile); //此处只能用filestream，用 System.Drawing.Image则会报多过进程访问文件的错误，会锁定文件 Bitmap bmPhoto = new Bitmap(CutWidth, CutHeight, System.Drawing.Imaging.PixelFormat.Format24bppRgb); bmPhoto.SetResolution(72, 72); Graphics gbmPhoto = Graphics.FromImage(bmPhoto); gbmPhoto.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; gbmPhoto.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; gbmPhoto.DrawImage( imgPhoto , new Rectangle(0, 0, CutWidth, CutHeight) , new Rectangle(PointX, PointY, CutHeight, CutHeight) , GraphicsUnit.Pixel ); bmPhoto.Save(sImgPath, System.Drawing.Imaging.ImageFormat.Jpeg); imgPhoto.Dispose(); gbmPhoto.Dispose(); bmPhoto.Dispose(); ms.Close(); return true; } catch { return false; } finally { } } }
希望本文所述对大家C#程序设计有所帮助。
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