xhwkclient/Common/system/ImageHelper.cs

using System;
using System.Configuration;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Text;
using System.Threading;
using System.Windows;
using System.Windows.Media;
using System.Windows.Media.Imaging;

namespace Common.system
{
    /// <summary>
    /// 图片帮助类
    /// 创建人：赵耀
    /// 创建时间：2018年11月1日
    /// </summary>
    public class ImageHelper
    {
        /// <summary>
        /// 通过FileStream 来打开文件，这样就可以实现不锁定Image文件，到时可以让多用户同时访问Image文件
        /// </summary>
        /// <param name="path">图片位置</param>
        /// <returns></returns>
        public static Bitmap ReadBitmapFile(string path)
        {
            try
            {
                if (File.Exists(path))
                {
                    FileStream fs = File.OpenRead(path); //OpenRead
                    int filelength = 0;
                    filelength = (int)fs.Length; //获得文件长度 
                    Byte[] image = new Byte[filelength]; //建立一个字节数组 
                    fs.Read(image, 0, filelength); //按字节流读取 
                    System.Drawing.Image result = System.Drawing.Image.FromStream(fs);
                    fs.Close();
                    Bitmap bit = new Bitmap(result);
                    return bit;
                }
                else
                    return null;
            }
            catch (Exception)
            {
                return null;
            }
        }
        /// <summary>
        /// 通过FileStream 来打开文件，这样就可以实现不锁定Image文件，到时可以让多用户同时访问Image文件
        /// </summary>
        /// <param name="path">图片位置</param>
        /// <returns></returns>
        public static Image ReadImageFile(string path)
        {
            try
            {
                if (File.Exists(path))
                {
                    FileStream fs = File.OpenRead(path); //OpenRead
                    int filelength = 0;
                    filelength = (int)fs.Length; //获得文件长度 
                    Byte[] image = new Byte[filelength]; //建立一个字节数组 
                    fs.Read(image, 0, filelength); //按字节流读取 
                    System.Drawing.Image result = System.Drawing.Image.FromStream(fs);
                    fs.Close();
                    return result;
                }
                else
                    return null;
            }
            catch (Exception)
            {
                return null;
            }
        }
        #region 获取RGB

        private static Bitmap _Bitmap = null;
        private static StringBuilder sb = new StringBuilder();

        public static string GetRGB(int x, int y)
        {
            sb = new StringBuilder();
            try
            {
                System.Drawing.Color color = _Bitmap.GetPixel(x, y);

                sb.Append("RGB:（");
                sb.Append(color.R.ToString());
                sb.Append(",");
                sb.Append(color.G.ToString());
                sb.Append(",");
                sb.Append(color.B.ToString());
                sb.Append("）");
            }
            catch (Exception ex)
            {
                LogHelper.WriteErrLog("ImageHelper(GetRGB)" + ex.Message, ex);
            }

            return sb.ToString();
        }

        #endregion 获取RGB
        #region 截图统一方法
        /// <summary>
        /// 截图通用方法 创建人：赵耀 创建时间：2020年8月11日
        /// </summary>
        /// <param name="ScreenSize">截图的区域，设置new Rectangle(0, 0, 0, 0)为截全屏</param>
        /// <param name="ImageSavePath">图片存储路径，为空或null则保存到临时文件夹</param>
        /// <param name="level">压缩等级，0到100，0 最差质量，100 最佳</param>
        /// <returns></returns>
        public static BitmapImage GetScreenshot(Rectangle ScreenSize, string ImageSavePath, long level = -1)
        {
            try
            {
                System.Drawing.Size bounds = PrimaryScreen.DESKTOP;
                if (string.IsNullOrEmpty(ImageSavePath))
                {
                    ImageSavePath = GetTempImagePath();//如果为空则指定临时存储路径
                }
                double scaleWidth = (bounds.Width * 1.0) / SystemParameters.PrimaryScreenWidth;
                double scaleHeight = (bounds.Height * 1.0) / SystemParameters.PrimaryScreenHeight;
                int width = bounds.Width;
                int height = bounds.Height;
                if (ScreenSize.Size != new System.Drawing.Size(0, 0))
                {
                    width = (int)(ScreenSize.Size.Width * scaleWidth);
                    height = (int)(ScreenSize.Size.Height * scaleHeight);
                }
                int l = (int)(ScreenSize.X * scaleWidth);
                int t = (int)(ScreenSize.Y * scaleHeight);
                if (_Bitmap != null)
                {
                    _Bitmap.Dispose();
                }
                _Bitmap = new Bitmap(width, height, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
                using (Graphics g = Graphics.FromImage(_Bitmap))
                {
                    g.CopyFromScreen(l, t, 0, 0, _Bitmap.Size, CopyPixelOperation.SourceCopy);
                    Compress(_Bitmap, ImageSavePath, level);
                }
                Uri uri = new Uri(ImageSavePath, UriKind.Absolute);
                BitmapImage bimg = new BitmapImage(uri);
                GC.Collect();
                return bimg;
            }
            catch (Exception ex)
            {
                LogHelper.WriteErrLog("【截图】(GetBitmapSource)截图失败，" + ex.Message, ex);
                return null;
            }
        }
        /// <summary>
        /// 获取临时图片保存位置
        /// </summary>
        /// <returns></returns>
        public static string GetTempImagePath()
        {
            TimeSpan ts = DateTime.Now - new DateTime(1970, 1, 1, 0, 0, 0, 0);
            
            string TempPath=FileToolsCommon.GetFileAbsolutePath("/temp/Screenshot/");
            FileToolsCommon.CreateDirectory(TempPath);
            TempPath += Convert.ToInt64(ts.TotalMilliseconds).ToString() + ".jpg";
            return TempPath;
        }
        #endregion 截图统一方法

        #region 图片压缩

        /// <summary>
        /// 图片压缩(降低质量以减小文件的大小) 创建人：赵耀 创建时间：2020年8月11日
        /// </summary>
        /// <param name="srcBitMap">传入的Bitmap对象</param>
        /// <param name="destFile">压缩后的图片保存路径</param>
        /// <param name="level">压缩等级，-1为config配置的值，0到100，0 最差质量，100 最佳</param>
        public static void Compress(Bitmap srcBitMap, string destFile, long level)
        {
            if (level <= -1)
            {
                int ImageCompressionLevel = int.Parse(FileToolsCommon.GetConfigValue("ImageCompressionLevel"));
                level = ImageCompressionLevel;
            }
            Stream s = new FileStream(destFile, FileMode.Create);
            Compress(srcBitMap, s, level);
            s.Close();
        }

        /// <summary>
        /// 图片压缩(降低质量以减小文件的大小) 创建人：赵耀 创建时间：2020年8月11日
        /// </summary>
        /// <param name="srcBitmap">传入的Bitmap对象</param>
        /// <param name="destStream">压缩后的Stream对象</param>
        /// <param name="level">压缩等级，0到100，0 最差质量，100 最佳</param>
        public static void Compress(Bitmap srcBitmap, Stream destStream, long level)
        {
            ImageCodecInfo myImageCodecInfo;
            System.Drawing.Imaging.Encoder myEncoder;
            EncoderParameter myEncoderParameter;
            EncoderParameters myEncoderParameters;

            //获取表示jpeg编解码器的imagecodecinfo对象
            myImageCodecInfo = GetEncoderInfo("image/jpeg");

            myEncoder = System.Drawing.Imaging.Encoder.Quality;

            myEncoderParameters = new EncoderParameters(1);

            myEncoderParameter = new EncoderParameter(myEncoder, level);
            myEncoderParameters.Param[0] = myEncoderParameter;
            srcBitmap.Save(destStream, myImageCodecInfo, myEncoderParameters);
        }

        /// <summary>
        /// 获取解码器 创建人：赵耀 创建时间2020年8月11日
        /// </summary>
        /// <param name="mimeType"></param>
        /// <returns></returns>
        private static ImageCodecInfo GetEncoderInfo(string mimeType)
        {
            int j;
            ImageCodecInfo[] encoders;
            encoders = ImageCodecInfo.GetImageEncoders();
            for (j = 0; j < encoders.Length; ++j)
            {
                if (encoders[j].MimeType == mimeType)
                {
                    return encoders[j];
                }
            }
            return null;
        }

        /// <summary>
        /// 压缩图片 -测试方法 待完善 暂无用
        /// </summary>
        /// <param name="_bitmap">原图片</param>
        /// <param name="dFile">压缩后保存图片地址</param>
        /// <param name="flag">压缩质量（数字越小压缩率越高）1-100</param>
        /// <param name="size">压缩后图片的最大大小</param>
        /// <param name="sfsc">是否是第一次调用</param>
        /// <returns></returns>
        public static bool CompressImage(Bitmap _bitmap, string dFile, int flag = 90, int size = 300)
        {
            ////如果是第一次调用，原始图像的大小小于要压缩的大小，则直接复制文件，并且返回true
            //FileInfo firstFileInfo = new FileInfo(sFile);
            //if (sfsc == true && firstFileInfo.Length < size * 1024)
            //{
            //    firstFileInfo.CopyTo(dFile);
            //    return true;
            //}
            //Image iSource = Image.FromFile(sFile);
            Image iSource = _bitmap;
            ImageFormat tFormat = iSource.RawFormat;
            int dHeight = iSource.Height / 2;
            int dWidth = iSource.Width / 2;
            int sW, sH;
            //按比例缩放
            System.Drawing.Size tem_size = new System.Drawing.Size(iSource.Width, iSource.Height);
            if (tem_size.Width > dHeight || tem_size.Width > dWidth)
            {
                if ((tem_size.Width * dHeight) > (tem_size.Width * dWidth))
                {
                    sW = dWidth;
                    sH = (dWidth * tem_size.Height) / tem_size.Width;
                }
                else
                {
                    sH = dHeight;
                    sW = (tem_size.Width * dHeight) / tem_size.Height;
                }
            }
            else
            {
                sW = tem_size.Width;
                sH = tem_size.Height;
            }

            Bitmap ob = new Bitmap(dWidth, dHeight);
            Graphics g = Graphics.FromImage(ob);

            g.Clear(System.Drawing.Color.WhiteSmoke);
            g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

            g.DrawImage(iSource, new Rectangle((dWidth - sW) / 2, (dHeight - sH) / 2, sW, sH), 0, 0, iSource.Width, iSource.Height, GraphicsUnit.Pixel);

            g.Dispose();

            //以下代码为保存图片时，设置压缩质量
            EncoderParameters ep = new EncoderParameters();
            long[] qy = new long[1];
            qy[0] = flag;//设置压缩的比例1-100
            EncoderParameter eParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, qy);
            ep.Param[0] = eParam;

            try
            {
                ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders();
                ImageCodecInfo jpegICIinfo = null;
                for (int x = 0; x < arrayICI.Length; x++)
                {
                    if (arrayICI[x].FormatDescription.Equals("JPEG"))
                    {
                        jpegICIinfo = arrayICI[x];
                        break;
                    }
                }
                if (jpegICIinfo != null)
                {
                    if (flag > 0)
                    {
                        ob.Save(dFile, jpegICIinfo, ep);//dFile是压缩后的新路径
                        FileInfo fi = new FileInfo(dFile);
                        if (fi.Length > 1024 * size)
                        {
                            flag -= 10;
                            CompressImage(_bitmap, dFile, flag, size);
                        }
                    }
                    //ob.Save(dFile, jpegICIinfo, ep);
                    //FileInfo fi = new FileInfo(dFile);
                    //bool IsAgain = false;
                    //if (fi.Length > 1024 * size)
                    //{
                    //    fi.CopyTo(dFile + fi.Length);
                    //    fi.Delete();
                    //    Bitmap newbitmap = ReadImageFile(dFile + fi.Length);
                    //    CompressImage(newbitmap, dFile, flag, size);
                    //    FileToolsCommon.DeleteFile(dFile + fi.Length);
                    //}
                }
                else
                {
                    ob.Save(dFile, tFormat);
                }
                return true;
            }
            catch
            {
                return false;
            }
            finally
            {
                iSource.Dispose();
                ob.Dispose();
            }
        }
        #endregion 图片压缩

        #region 截屏指定UI控件
        /// <summary>
        /// 保存图片
        /// </summary>
        /// <param name="ui">需要截图的UI控件</param>
        /// <param name="filePathName">图片保存地址 命名 1.png</param>
        /// <param name="width">保存宽</param>
        /// <param name="height">保存高</param>
        public static void SaveUIToImage(FrameworkElement ui, string filePathName, int width, int height)
        {
            try
            {
                System.IO.FileStream fs = new System.IO.FileStream(filePathName, System.IO.FileMode.Create);
                //在位图中呈现UI元素
                RenderTargetBitmap bmp = new RenderTargetBitmap(width, height, 96d, 96d,
                PixelFormats.Pbgra32);
                bmp.Render(ui);
                BitmapEncoder encoder = new PngBitmapEncoder();
                encoder.Frames.Add(BitmapFrame.Create(bmp));
                encoder.Save(fs);
                fs.Close();
                new Thread(new ThreadStart(new Action(() =>
                {
                    Bitmap bitmap = CutImageWhitePart(filePathName);
                    FileToolsCommon.DeleteFile(filePathName);
                    bitmap.Save(filePathName);
                }))).Start();
            }
            catch (Exception ex)
            {
                LogHelper.WriteErrLog("【UI生成图片】（SaveUIToImage）" + ex.Message, ex);
                //Console.WriteLine(ex.Message);
            }
        }
        #endregion

        #region 去掉白边
        /// <summary>
        /// 裁剪图片（去掉白边）
        /// </summary>
        /// <param name="FilePath"></param>
        public static Bitmap CutImageWhitePart(string FilePath)
        {
            Bitmap bmp = new Bitmap(FilePath);
            //上左右下
            int top = 0, left = 0, right = bmp.Width, bottom = bmp.Height;

            //寻找最上面的标线,从左(0)到右，从上(0)到下
            for (int i = 0; i < bmp.Height; i++)//行
            {
                bool find = false;
                for (int j = 0; j < bmp.Width; j++)//列
                {
                    System.Drawing.Color c = bmp.GetPixel(j, i);
                    if (!IsWhite(c))
                    {
                        top = i;
                        find = true;
                        break;
                    }
                }
                if (find)
                    break;
            }
            //寻找最左边的标线，从上（top位）到下，从左到右
            for (int i = 0; i < bmp.Width; i++)//列
            {
                bool find = false;
                for (int j = top; j < bmp.Height; j++)//行
                {
                    System.Drawing.Color c = bmp.GetPixel(i, j);
                    if (!IsWhite(c))
                    {
                        left = i;
                        find = true;
                        break;
                    }
                }
                if (find)
                    break;
            }
            //寻找最下边标线，从下到上，从左到右
            for (int i = bmp.Height - 1; i >= 0; i--)//行
            {
                bool find = false;
                for (int j = left; j < bmp.Width; j++)//列
                {
                    System.Drawing.Color c = bmp.GetPixel(j, i);
                    if (!IsWhite(c))
                    {
                        bottom = i;
                        find = true;
                        break;
                    }
                }
                if (find)
                    break;
            }
            //寻找最右边的标线，从上到下，从右往左
            for (int i = bmp.Width - 1; i >= 0; i--)//列
            {
                bool find = false;
                for (int j = 0; j <= bottom; j++)//行
                {
                    System.Drawing.Color c = bmp.GetPixel(i, j);
                    if (!IsWhite(c))
                    {
                        right = i;
                        find = true;
                        break;
                    }
                }
                if (find)
                    break;
            }

            //克隆位图对象的一部分。
            System.Drawing.Rectangle cloneRect = new System.Drawing.Rectangle(left, top, right - left, bottom - top);
            Bitmap cloneBitmap = bmp.Clone(cloneRect, bmp.PixelFormat);
            bmp.Dispose();
            //cloneBitmap.Save(@"d:\123.png", ImageFormat.Png);
            return cloneBitmap;
        }

        /// <summary>
        /// 判断是否白色和纯透明色（10点的容差）
        /// </summary>
        public static bool IsWhite(System.Drawing.Color c)
        {
            //纯透明也是白色,RGB都为255为纯白
            if (c.A < 10 || (c.R > 245 && c.G > 245 && c.B > 245))
                return true;

            return false;
        }
        #endregion
    }
}