C#图片处理类
转载來源：简书
转载作者：幻凌风
转载来源：https://www.jianshu.com/p/e1bab83e87ce
using System; using System.Collections; using System.IO; using System.Drawing; using System.Drawing.Imaging; using System.Drawing.Drawing2D; namespace StudyCommon { public class ImageClass { public ImageClass() { } #region 缩略图 /// <summary> /// 生成缩略图 /// </summary> /// <param name="originalImagePath">源图路径（物理路径）</param> /// <param name="thumbnailPath">缩略图路径（物理路径）</param> /// <param name="width">缩略图宽度</param> /// <param name="height">缩略图高度</param> /// <param name="mode">生成缩略图的方式</param> public static void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode) { System.Drawing.Image originalImage = System.Drawing.Image.FromFile(originalImagePath); int towidth = width; int toheight = height; int x = 0; int y = 0; int ow = originalImage.Width; int oh = originalImage.Height; switch (mode) { case "HW": //指定高宽缩放（可能变形） break; case "W": //指定宽，高按比例 toheight = originalImage.Height * width / originalImage.Width; break; case "H": //指定高，宽按比例 towidth = originalImage.Width * height / originalImage.Height; break; case "Cut": //指定高宽裁减（不变形） if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight) { oh = originalImage.Height; ow = originalImage.Height * towidth / toheight; y = 0; x = (originalImage.Width - ow) / 2; } else { ow = originalImage.Width; oh = originalImage.Width * height / towidth; x = 0; y = (originalImage.Height - oh) / 2; } break; default: break; } //新建一个bmp图片 System.Drawing.Image bitmap = new System.Drawing.Bitmap(towidth, toheight); //新建一个画板 System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bitmap); //设置高质量插值法 g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; //设置高质量,低速度呈现平滑程度 g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; //清空画布并以透明背景色填充 g.Clear(System.Drawing.Color.Transparent); //在指定位置并且按指定大小绘制原图片的指定部分 //第一个：对哪张图片进行操作。 //二：画多么大。 //三：画那块区域。 g.DrawImage(originalImage, new System.Drawing.Rectangle(0, 0, towidth, toheight), new System.Drawing.Rectangle(x, y, ow, oh), System.Drawing.GraphicsUnit.Pixel); try { //以jpg格式保存缩略图 bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg); } catch (System.Exception e) { throw e; } finally { originalImage.Dispose(); bitmap.Dispose(); g.Dispose(); } } #endregion #region 图片水印 /// <summary> /// 图片水印处理方法 /// </summary> /// <param name="path">需要加载水印的图片路径（绝对路径）</param> /// <param name="waterpath">水印图片（绝对路径）</param> /// <param name="location">水印位置（传送正确的代码）</param> public static string ImageWatermark(string path, string waterpath, string location) { string kz_name = Path.GetExtension(path); if (kz_name == ".jpg" || kz_name == ".bmp" || kz_name == ".jpeg") { DateTime time = DateTime.Now; string filename = "" + time.Year.ToString() + time.Month.ToString() + time.Day.ToString() + time.Hour.ToString() + time.Minute.ToString() + time.Second.ToString() + time.Millisecond.ToString(); Image img = Bitmap.FromFile(path); Image waterimg = Image.FromFile(waterpath); Graphics g = Graphics.FromImage(img); ArrayList loca = GetLocation(location, img, waterimg); g.DrawImage(waterimg, new Rectangle(int.Parse(loca[0].ToString()), int.Parse(loca[1].ToString()), waterimg.Width, waterimg.Height)); waterimg.Dispose(); g.Dispose(); string newpath = Path.GetDirectoryName(path) + filename + kz_name; img.Save(newpath); img.Dispose(); File.Copy(newpath, path, true); if (File.Exists(newpath)) { File.Delete(newpath); } } return path; } /// <summary> /// 图片水印位置处理方法 /// </summary> /// <param name="location">水印位置</param> /// <param name="img">需要添加水印的图片</param> /// <param name="waterimg">水印图片</param> private static ArrayList GetLocation(string location, Image img, Image waterimg) { ArrayList loca = new ArrayList(); int x = 0; int y = 0; if (location == "LT") { x = 10; y = 10; } else if (location == "T") { x = img.Width / 2 - waterimg.Width / 2; y = img.Height - waterimg.Height; } else if (location == "RT") { x = img.Width - waterimg.Width; y = 10; } else if (location == "LC") { x = 10; y = img.Height / 2 - waterimg.Height / 2; } else if (location == "C") { x = img.Width / 2 - waterimg.Width / 2; y = img.Height / 2 - waterimg.Height / 2; } else if (location == "RC") { x = img.Width - waterimg.Width; y = img.Height / 2 - waterimg.Height / 2; } else if (location == "LB") { x = 10; y = img.Height - waterimg.Height; } else if (location == "B") { x = img.Width / 2 - waterimg.Width / 2; y = img.Height - waterimg.Height; } else { x = img.Width - waterimg.Width; y = img.Height - waterimg.Height; } loca.Add(x); loca.Add(y); return loca; } #endregion #region 文字水印 /// <summary> /// 文字水印处理方法 /// </summary> /// <param name="path">图片路径（绝对路径）</param> /// <param name="size">字体大小</param> /// <param name="letter">水印文字</param> /// <param name="color">颜色</param> /// <param name="location">水印位置</param> public static string LetterWatermark(string path, int size, string letter, Color color, string location) { #region string kz_name = Path.GetExtension(path); if (kz_name == ".jpg" || kz_name == ".bmp" || kz_name == ".jpeg") { DateTime time = DateTime.Now; string filename = "" + time.Year.ToString() + time.Month.ToString() + time.Day.ToString() + time.Hour.ToString() + time.Minute.ToString() + time.Second.ToString() + time.Millisecond.ToString(); Image img = Bitmap.FromFile(path); Graphics gs = Graphics.FromImage(img); ArrayList loca = GetLocation(location, img, size, letter.Length); Font font = new Font("宋体", size); Brush br = new SolidBrush(color); gs.DrawString(letter, font, br, float.Parse(loca[0].ToString()), float.Parse(loca[1].ToString())); gs.Dispose(); string newpath = Path.GetDirectoryName(path) + filename + kz_name; img.Save(newpath); img.Dispose(); File.Copy(newpath, path, true); if (File.Exists(newpath)) { File.Delete(newpath); } } return path; #endregion } /// <summary> /// 文字水印位置的方法 /// </summary> /// <param name="location">位置代码</param> /// <param name="img">图片对象</param> /// <param name="width">宽(当水印类型为文字时,传过来的就是字体的大小)</param> /// <param name="height">高(当水印类型为文字时,传过来的就是字符的长度)</param> private static ArrayList GetLocation(string location, Image img, int width, int height) { #region ArrayList loca = new ArrayList(); //定义数组存储位置 float x = 10; float y = 10; if (location == "LT") { loca.Add(x); loca.Add(y); } else if (location == "T") { x = img.Width / 2 - (width * height) / 2; loca.Add(x); loca.Add(y); } else if (location == "RT") { x = img.Width - width * height; } else if (location == "LC") { y = img.Height / 2; } else if (location == "C") { x = img.Width / 2 - (width * height) / 2; y = img.Height / 2; } else if (location == "RC") { x = img.Width - height; y = img.Height / 2; } else if (location == "LB") { y = img.Height - width - 5; } else if (location == "B") { x = img.Width / 2 - (width * height) / 2; y = img.Height - width - 5; } else { x = img.Width - width * height; y = img.Height - width - 5; } loca.Add(x); loca.Add(y); return loca; #endregion } #endregion #region 调整光暗 /// <summary> /// 调整光暗 /// </summary> /// <param name="mybm">原始图片</param> /// <param name="width">原始图片的长度</param> /// <param name="height">原始图片的高度</param> /// <param name="val">增加或减少的光暗值</param> public Bitmap LDPic(Bitmap mybm, int width, int height, int val) { Bitmap bm = new Bitmap(width, height);//初始化一个记录经过处理后的图片对象 int x, y, resultR, resultG, resultB;//x、y是循环次数，后面三个是记录红绿蓝三个值的 Color pixel; for (x = 0; x < width; x++) { for (y = 0; y < height; y++) { pixel = mybm.GetPixel(x, y);//获取当前像素的值 resultR = pixel.R + val;//检查红色值会不会超出[0, 255] resultG = pixel.G + val;//检查绿色值会不会超出[0, 255] resultB = pixel.B + val;//检查蓝色值会不会超出[0, 255] bm.SetPixel(x, y, Color.FromArgb(resultR, resultG, resultB));//绘图 } } return bm; } #endregion #region 反色处理 /// <summary> /// 反色处理 /// </summary> /// <param name="mybm">原始图片</param> /// <param name="width">原始图片的长度</param> /// <param name="height">原始图片的高度</param> public Bitmap RePic(Bitmap mybm, int width, int height) { Bitmap bm = new Bitmap(width, height);//初始化一个记录处理后的图片的对象 int x, y, resultR, resultG, resultB; Color pixel; for (x = 0; x < width; x++) { for (y = 0; y < height; y++) { pixel = mybm.GetPixel(x, y);//获取当前坐标的像素值 resultR = 255 - pixel.R;//反红 resultG = 255 - pixel.G;//反绿 resultB = 255 - pixel.B;//反蓝 bm.SetPixel(x, y, Color.FromArgb(resultR, resultG, resultB));//绘图 } } return bm; } #endregion #region 浮雕处理 /// <summary> /// 浮雕处理 /// </summary> /// <param name="oldBitmap">原始图片</param> /// <param name="Width">原始图片的长度</param> /// <param name="Height">原始图片的高度</param> public Bitmap FD(Bitmap oldBitmap, int Width, int Height) { Bitmap newBitmap = new Bitmap(Width, Height); Color color1, color2; for (int x = 0; x < Width - 1; x++) { for (int y = 0; y < Height - 1; y++) { int r = 0, g = 0, b = 0; color1 = oldBitmap.GetPixel(x, y); color2 = oldBitmap.GetPixel(x + 1, y + 1); r = Math.Abs(color1.R - color2.R + 128); g = Math.Abs(color1.G - color2.G + 128); b = Math.Abs(color1.B - color2.B + 128); if (r > 255) r = 255; if (r < 0) r = 0; if (g > 255) g = 255; if (g < 0) g = 0; if (b > 255) b = 255; if (b < 0) b = 0; newBitmap.SetPixel(x, y, Color.FromArgb(r, g, b)); } } return newBitmap; } #endregion #region 拉伸图片 /// <summary> /// 拉伸图片 /// </summary> /// <param name="bmp">原始图片</param> /// <param name="newW">新的宽度</param> /// <param name="newH">新的高度</param> public static Bitmap ResizeImage(Bitmap bmp, int newW, int newH) { try { Bitmap bap = new Bitmap(newW, newH); Graphics g = Graphics.FromImage(bap); g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic; g.DrawImage(bap, new Rectangle(0, 0, newW, newH), new Rectangle(0, 0, bap.Width, bap.Height), GraphicsUnit.Pixel); g.Dispose(); return bap; } catch { return null; } } #endregion #region 滤色处理 /// <summary> /// 滤色处理 /// </summary> /// <param name="mybm">原始图片</param> /// <param name="width">原始图片的长度</param> /// <param name="height">原始图片的高度</param> public Bitmap FilPic(Bitmap mybm, int width, int height) { Bitmap bm = new Bitmap(width, height);//初始化一个记录滤色效果的图片对象 int x, y; Color pixel; for (x = 0; x < width; x++) { for (y = 0; y < height; y++) { pixel = mybm.GetPixel(x, y);//获取当前坐标的像素值 bm.SetPixel(x, y, Color.FromArgb(0, pixel.G, pixel.B));//绘图 } } return bm; } #endregion #region 左右翻转 /// <summary> /// 左右翻转 /// </summary> /// <param name="mybm">原始图片</param> /// <param name="width">原始图片的长度</param> /// <param name="height">原始图片的高度</param> public Bitmap RevPicLR(Bitmap mybm, int width, int height) { Bitmap bm = new Bitmap(width, height); int x, y, z; //x,y是循环次数,z是用来记录像素点的x坐标的变化的 Color pixel; for (y = height - 1; y >= 0; y--) { for (x = width - 1, z = 0; x >= 0; x--) { pixel = mybm.GetPixel(x, y);//获取当前像素的值 bm.SetPixel(z++, y, Color.FromArgb(pixel.R, pixel.G, pixel.B));//绘图 } } return bm; } #endregion #region 上下翻转 /// <summary> /// 上下翻转 /// </summary> /// <param name="mybm">原始图片</param> /// <param name="width">原始图片的长度</param> /// <param name="height">原始图片的高度</param> public Bitmap RevPicUD(Bitmap mybm, int width, int height) { Bitmap bm = new Bitmap(width, height); int x, y, z; Color pixel; for (x = 0; x < width; x++) { for (y = height - 1, z = 0; y >= 0; y--) { pixel = mybm.GetPixel(x, y);//获取当前像素的值 bm.SetPixel(x, z++, Color.FromArgb(pixel.R, pixel.G, pixel.B));//绘图 } } return bm; } #endregion #region 压缩图片 /// <summary> /// 压缩到指定尺寸 /// </summary> /// <param name="oldfile">原文件</param> /// <param name="newfile">新文件</param> public bool Compress(string oldfile, string newfile) { try { System.Drawing.Image img = System.Drawing.Image.FromFile(oldfile); System.Drawing.Imaging.ImageFormat thisFormat = img.RawFormat; Size newSize = new Size(100, 125); Bitmap outBmp = new Bitmap(newSize.Width, newSize.Height); Graphics g = Graphics.FromImage(outBmp); g.CompositingQuality = CompositingQuality.HighQuality; g.SmoothingMode = SmoothingMode.HighQuality; g.InterpolationMode = InterpolationMode.HighQualityBicubic; g.DrawImage(img, new Rectangle(0, 0, newSize.Width, newSize.Height), 0, 0, img.Width, img.Height, GraphicsUnit.Pixel); g.Dispose(); EncoderParameters encoderParams = new EncoderParameters(); long[] quality = new long[1]; quality[0] = 100; EncoderParameter encoderParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality); encoderParams.Param[0] = encoderParam; ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders(); ImageCodecInfo jpegICI = null; for (int x = 0; x < arrayICI.Length; x++) if (arrayICI[x].FormatDescription.Equals("JPEG")) { jpegICI = arrayICI[x]; //设置JPEG编码 break; } img.Dispose(); if (jpegICI != null) outBmp.Save(newfile, System.Drawing.Imaging.ImageFormat.Jpeg); outBmp.Dispose(); return true; } catch { return false; } } #endregion #region 图片灰度化 public Color Gray(Color c) { int rgb = Convert.ToInt32((double)(((0.3 * c.R) + (0.59 * c.G)) + (0.11 * c.B))); return Color.FromArgb(rgb, rgb, rgb); } #endregion #region 转换为黑白图片 /// <summary> /// 转换为黑白图片 /// </summary> /// <param name="mybt">要进行处理的图片</param> /// <param name="width">图片的长度</param> /// <param name="height">图片的高度</param> public Bitmap BWPic(Bitmap mybm, int width, int height) { Bitmap bm = new Bitmap(width, height); int x, y, result; //x,y是循环次数，result是记录处理后的像素值 Color pixel; for (x = 0; x < width; x++) { for (y = 0; y < height; y++) { pixel = mybm.GetPixel(x, y);//获取当前坐标的像素值 result = (pixel.R + pixel.G + pixel.B) / 3;//取红绿蓝三色的平均值 bm.SetPixel(x, y, Color.FromArgb(result, result, result)); } } return bm; } #endregion #region 获取图片中的各帧 /// <summary> /// 获取图片中的各帧 /// </summary> /// <param name="pPath">图片路径</param> /// <param name="pSavePath">保存路径</param> public void GetFrames(string pPath, string pSavedPath) { Image gif = Image.FromFile(pPath); FrameDimension fd = new FrameDimension(gif.FrameDimensionsList[0]); int count = gif.GetFrameCount(fd); //获取帧数(gif图片可能包含多帧，其它格式图片一般仅一帧) for (int i = 0; i < count; i++) //以Jpeg格式保存各帧 { gif.SelectActiveFrame(fd, i); gif.Save(pSavedPath + "\\frame_" + i + ".jpg", ImageFormat.Jpeg); } } #endregion } } 作者：幻凌风 链接：https://www.jianshu.com/p/e1bab83e87ce 來源：简书 简书著作权归作者所有，任何形式的转载都请联系作者获得授权并注明出处。
