using System;
using System.IO;
using System.Collections;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;

namespace Imag_writer
{
/// <summary>
/// 水印的類型
/// </summary>
public enum WaterMarkType
{
?? /// <summary>
?? /// 文字水印
?? /// </summary>
?? TextMark,
?? /// <summary>
?? /// 圖片水印
?? /// </summary>
?? //ImageMark // 暫時只能添加文字水印
};

/// <summary>
/// 水印的位置
/// </summary>
public enum WaterMarkPosition
{
?? /// <summary>
?? /// 左上角
?? /// </summary>
?? WMP_Left_Top,
?? /// <summary>
?? /// 左下角
?? /// </summary>
?? WMP_Left_Bottom,
?? /// <summary>
?? /// 右上角
?? /// </summary>
?? WMP_Right_Top,
?? /// <summary>
?? /// 右下角
?? /// </summary>
?? WMP_Right_Bottom
};

/// <summary>
/// 處理圖片的類（包括加水印，生成縮略圖）
/// </summary>
public class ImageWaterMark
{
?? public ImageWaterMark()
?? {
??? //
??? // TODO: 在此處添加構造函數邏輯
??? //
?? }

?? #region 給圖片加水印
?? /// <summary>
?? /// 添加水印(分圖片水印與文字水印兩種)
?? /// </summary>
?? /// <param name="oldpath">原圖片絕對地址</param>
?? /// <param name="newpath">新圖片放置的絕對地址</param>
?? /// <param name="wmtType">要添加的水印的類型</param>
?? /// <param name="sWaterMarkContent">水印內容，若添加文字水印，此即為要添加的文字；
?? /// 若要添加圖片水印，此為圖片的路徑</param>
?? public void addWaterMark(string oldpath, string newpath,
??? WaterMarkType wmtType, string sWaterMarkContent)
?? {
??? try
??? {
???? Image image = Image.FromFile(oldpath);

???? Bitmap b = new Bitmap(image.Width, image.Height,
????? PixelFormat.Format24bppRgb);

???? Graphics g = Graphics.FromImage(b);
???? g.Clear(Color.White);
???? g.SmoothingMode = SmoothingMode.HighQuality;
???? g.InterpolationMode = InterpolationMode.High;

???? g.DrawImage(image, 0, 0, image.Width, image.Height);

???? switch (wmtType)
???? {
????? /*case WaterMarkType.ImageMark:
?????? //圖片水印
?????? this.addWatermarkImage(g,
??????? Page.Server.MapPath(Watermarkimgpath),
??????? WatermarkPosition,image.Width,image.Height);
?????? break;*/
????? case WaterMarkType.TextMark:
?????? //文字水印
?????? this.addWatermarkText(g, sWaterMarkContent, "WM_BOTTOM_RIGHT",
??????? image.Width, image.Height);
?????? break;
???? }

???? b.Save(newpath);
???? b.Dispose();
???? image.Dispose();
??? }
??? catch
??? {
???? if(File.Exists(oldpath))
???? {
????? File.Delete(oldpath);
???? }
??? }
??? finally
??? {
???? if(File.Exists(oldpath))
???? {
????? File.Delete(oldpath);
???? }
??? }??
?? }

?? /// <summary>
?? ///?? 加水印文字
?? /// </summary>
?? /// <param name="picture">imge 對象</param>
?? /// <param name="_watermarkText">水印文字內容</param>
?? /// <param name="_watermarkPosition">水印位置</param>
?? /// <param name="_width">被加水印圖片的寬</param>
?? /// <param name="_height">被加水印圖片的高</param>
?? ******* void addWatermarkText(Graphics picture, string _watermarkText,
??? string _watermarkPosition, int _width, int _height)
?? {
??? // 確定水印文字的字體大小
??? int[] sizes = new int[]{32, 30, 28, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4};
??? Font crFont = null;
??? SizeF crSize = new SizeF();
??? for (int i = 0;i < sizes.Length; i++)
??? {
???? crFont = new Font("Arial Black", sizes[i], FontStyle.Bold);
???? crSize = picture.MeasureString(_watermarkText, crFont);

???? if((ushort)crSize.Width < (ushort)_width)
???? {
????? break;
???? }
??? }

??? // 生成水印圖片（將文字寫到圖片中）
??? Bitmap floatBmp = new Bitmap((int)crSize.Width + 3,
????????? (int)crSize.Height + 3, PixelFormat.Format32bppArgb);
??? Graphics fg=Graphics.FromImage(floatBmp);
??? PointF pt=new PointF(0,0);

??? // 畫陰影文字
??? Brush TransparentBrush0 = new SolidBrush(Color.FromArgb(255, Color.Black));
??? Brush TransparentBrush1 = new SolidBrush(Color.FromArgb(255, Color.Black));
??? fg.DrawString(_watermarkText,crFont,TransparentBrush0, pt.X, pt.Y + 1);
??? fg.DrawString(_watermarkText,crFont,TransparentBrush0, pt.X + 1, pt.Y);

??? fg.DrawString(_watermarkText,crFont,TransparentBrush1, pt.X + 1, pt.Y + 1);
??? fg.DrawString(_watermarkText,crFont,TransparentBrush1, pt.X, pt.Y + 2);
??? fg.DrawString(_watermarkText,crFont,TransparentBrush1, pt.X + 2, pt.Y);

??? TransparentBrush0.Dispose();
??? TransparentBrush1.Dispose();

??? // 畫文字
??? fg.SmoothingMode=System.Drawing.Drawing2D.SmoothingMode.HighQuality;
??? fg.DrawString(_watermarkText,
???? crFont, new SolidBrush(Color.White),
???? pt.X, pt.Y, StringFormat.GenericDefault);

??? // 保存剛才的操作
??? fg.Save();
??? fg.Dispose();
??? // floatBmp.Save("d:\\WebSite\\DIGITALKM\\ttt.jpg");

??? // 將水印圖片加到原圖中
??? this.addWatermarkImage(
???? picture,
???? new Bitmap(floatBmp),
???? "WM_BOTTOM_RIGHT",
???? _width,
???? _height);
?? }

?? /// <summary>
?? ///?? 加水印圖片
?? /// </summary>
?? /// <param name="picture">imge 對象</param>
?? /// <param name="iTheImage">Image對象（以此圖片為水印）</param>
?? /// <param name="_watermarkPosition">水印位置</param>
?? /// <param name="_width">被加水印圖片的寬</param>
?? /// <param name="_height">被加水印圖片的高</param>
?? ******* void addWatermarkImage( Graphics picture,Image iTheImage,
??? string _watermarkPosition,int _width,int _height)
?? {
??? Image watermark = new Bitmap(iTheImage);

??? ImageAttributes imageAttributes = new ImageAttributes();
??? 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, ColorAdjustType.Bitmap);

??? 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, 0.3f, 0.0f},
???????????? new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f}
??????????? };

??? ColorMatrix colorMatrix = new ColorMatrix(colorMatrixElements);

??? imageAttributes.SetColorMatrix(colorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);

??? int xpos = 0;
??? int ypos = 0;
??? int WatermarkWidth = 0;
??? int WatermarkHeight = 0;
??? double bl = 1d;

??? //計算水印圖片的比率
??? //取背景的1/4寬度來比較
??? if ((_width > watermark.Width * 4) && (_height > watermark.Height * 4))
??? {
???? bl = 1;
??? }
??? else if ((_width > watermark.Width * 4) && (_height<watermark.Height * 4))
??? {
???? bl = Convert.ToDouble(_height / 4) / Convert.ToDouble(watermark.Height);
????????????
??? }
??? else if ((_width < watermark.Width * 4) && (_height > watermark.Height * 4))
??? {
???? bl = Convert.ToDouble(_width / 4) / Convert.ToDouble(watermark.Width);
??? }
??? else
??? {
???? if ((_width * watermark.Height) > (_height * watermark.Width))
???? {
????? bl = Convert.ToDouble(_height / 4) / Convert.ToDouble(watermark.Height);
????????????????????
???? }
???? else
???? {
????? bl = Convert.ToDouble(_width / 4) / Convert.ToDouble(watermark.Width);
????????????????????
???? }
????????????
??? }

??? WatermarkWidth = Convert.ToInt32(watermark.Width * bl);
??? WatermarkHeight = Convert.ToInt32(watermark.Height * bl);

??? switch (_watermarkPosition)
??? {
???? case "WM_TOP_LEFT":
????? xpos = 10;
????? ypos = 10;
????? break;
???? case "WM_TOP_RIGHT":
????? xpos = _width - WatermarkWidth - 10;
????? ypos = 10;
????? break;
???? case "WM_BOTTOM_RIGHT":
????? xpos = _width - WatermarkWidth - 10;
????? ypos = _height -WatermarkHeight - 10;
????? break;
???? case "WM_BOTTOM_LEFT":
????? xpos = 10;
????? ypos = _height - WatermarkHeight - 10;
????? break;
??? }

??? picture.DrawImage(
???? watermark,
???? new Rectangle(xpos, ypos, WatermarkWidth, WatermarkHeight),
???? 0,
???? 0,
???? watermark.Width,
???? watermark.Height,
???? GraphicsUnit.Pixel,
???? imageAttributes);

??? watermark.Dispose();
??? imageAttributes.Dispose();
?? }

?? /// <summary>
?? ///?? 加水印圖片
?? /// </summary>
?? /// <param name="picture">imge 對象</param>
?? /// <param name="WaterMarkPicPath">水印圖片的地址</param>
?? /// <param name="_watermarkPosition">水印位置</param>
?? /// <param name="_width">被加水印圖片的寬</param>
?? /// <param name="_height">被加水印圖片的高</param>
?? ******* void addWatermarkImage( Graphics picture,string WaterMarkPicPath,
??? string _watermarkPosition,int _width,int _height)
?? {
??? Image watermark = new Bitmap(WaterMarkPicPath);

??? this.addWatermarkImage(picture, watermark, _watermarkPosition, _width,
???? _height);
?? }
?? #endregion

?? #region 生成縮略圖
?? /// <summary>
?? /// 保存圖片
?? /// </summary>
?? /// <param name="image">Image 對象</param>
?? /// <param name="savePath">保存路徑</param>
?? /// <param name="ici">指定格式的編解碼參數</param>
?? ******* void SaveImage(Image image, string savePath, ImageCodecInfo ici)
?? {
??? //設置 原圖片 對象的 EncoderParameters 對象
??? EncoderParameters parameters = new EncoderParameters(1);
??? parameters.Param[0] = new EncoderParameter(
???? System.Drawing.Imaging.Encoder.Quality, ((long) 90));
??? image.Save(savePath, ici, parameters);
??? parameters.Dispose();
?? }

?? /// <summary>
?? /// 獲取圖像編碼解碼器的所有相關信息
?? /// </summary>
?? /// <param name="mimeType">包含編碼解碼器的多用途網際郵件擴充協議 (MIME) 類型的字符串</param>
?? /// <returns>返回圖像編碼解碼器的所有相關信息</returns>
?? ******* ImageCodecInfo GetCodecInfo(string mimeType)
?? {
??? ImageCodecInfo[] CodecInfo = ImageCodecInfo.GetImageEncoders();
??? foreach(ImageCodecInfo ici in CodecInfo)
??? {
???? if(ici.MimeType == mimeType)
????? return ici;
??? }
??? return null;
?? }

?? /// <summary>
?? /// 生成縮略圖
?? /// </summary>
?? /// <param name="sourceImagePath">原圖片路徑(相對路徑)</param>
?? /// <param name="thumbnailImagePath">生成的縮略圖路徑,如果為空則保存為原圖片路徑(相對路徑)</param>
?? /// <param name="thumbnailImageWidth">縮略圖的寬度（高度與按源圖片比例自動生成）</param>
?? public void ToThumbnailImages(
??? string SourceImagePath,
??? string ThumbnailImagePath,
??? int ThumbnailImageWidth)
?? {
??? Hashtable htmimes = new Hashtable();
??? htmimes[".jpeg"] = "image/jpeg";
??? htmimes[".jpg"] = "image/jpeg";???
??? htmimes[".png"] = "image/png";???
??? htmimes[".tif"] = "image/tiff";
??? htmimes[".tiff"] = "image/tiff";
??? htmimes[".bmp"] = "image/bmp";
??? htmimes[".gif"] = "image/gif";

??? // 取得原圖片的后綴
??? string sExt = SourceImagePath.Substring(
???? SourceImagePath.LastIndexOf(".")).ToLower();

??? //從 原圖片 創建 Image 對象
??? Image image = Image.FromFile(SourceImagePath);??
??? int num = ((ThumbnailImageWidth / 4) * 3);
??? int width = image.Width;
??? int height = image.Height;

??? //計算圖片的比例
??? if ((((double) width) / ((double) height)) >= 1.3333333333333333f)
??? {
???? num = ((height * ThumbnailImageWidth) / width);
??? }
??? else
??? {
???? ThumbnailImageWidth = ((width * num) / height);
??? }
??? if ((ThumbnailImageWidth < 1) || (num < 1))
??? {
???? return;
??? }

??? //用指定的大小和格式初始化 Bitmap 類的新實例
??? Bitmap bitmap = new Bitmap(ThumbnailImageWidth, num,
???? PixelFormat.Format32bppArgb);

??? //從指定的 Image 對象創建新 Graphics 對象
??? Graphics graphics = Graphics.FromImage(bitmap);

??? //清除整個繪圖面并以透明背景色填充
??? graphics.Clear(Color.Transparent);

??? graphics.SmoothingMode = SmoothingMode.HighQuality;
??? graphics.InterpolationMode = InterpolationMode.High;

??? //在指定位置并且按指定大小繪制 原圖片 對象
??? graphics.DrawImage(image, new Rectangle(0, 0, ThumbnailImageWidth, num));
??? image.Dispose();
???
??? try
??? {???
???? //將此 原圖片 以指定格式并用指定的編解碼參數保存到指定文件
???? SaveImage(bitmap, ThumbnailImagePath,
????? GetCodecInfo((string)htmimes[sExt]));
??? }
??? catch(System.Exception e)
??? {
???? throw e;
??? }
?? }
?? #endregion
}
}

?

轉載于:https://www.cnblogs.com/hackpig/archive/2010/02/15/1668379.html

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