更换获取缩略图的方式，解决部分电脑无法生成缩略图的问题

XHWK.WKTool/App.config

     <!--参数是否加密 0不加密 1加密-->
     <add key="IsParameterEncryption" value="0" />
     <!--版本号-->
-    <add key="VersionCode" value="120" />
-    <add key="VersionName" value="3.9.3" />
+    <add key="VersionCode" value="121" />
+    <add key="VersionName" value="3.9.4" />
     <!--皮肤样式 0白 1蓝 2黑色 -->
     <add key="SkinStyle" value="0" />
     <!--是否输出视频记录日志：0否-->

XHWK.WKTool/MainWindow.xaml.cs

         /// </param>
         private void BtnScreenshot_Click(object sender, RoutedEventArgs e)
         {
+            if (_recordType == 4)
+            {
+                return;
+            }
             JietuAction();
         }
 
                             killProcess.Kill();
                         }
                         FFMpegConverter ffMpeg = new FFMpegConverter();
-                        FFMpegInput[] input = new FFMpegInput[]
+                        FFMpegInput[] input =
                         {
                             new FFMpegInput(_tempVideoPathName),
                             new FFMpegInput(_tempAudioPathName)
                         _videoInfo.Uploaded = 0;
                         try
                         {
-                            App.FFmpeg.GenerateThumbnails
-                            (
-                                _tempVideoPathName,
-                                thumbnailPathName,
-                                200,
-                                130
-                            );
+                            ZVideoRecordHelper.GetVideoPic(_tempVideoPathName, thumbnailPathName);
                         }
                         catch (Exception ex)
                         {

XHWK.WKTool/ScreenRecordingToolbarWindow.xaml.cs

                             _videoInfo.RSTime = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss");
                             _videoInfo.VideoPath = _videoSavePathName;
                             _videoInfo.ThumbnailPath = thumbnailPathName;
-                            App.FFmpeg.GenerateThumbnails
-                            (
-                                _videoSavePathName,
-                                thumbnailPathName,
-                                200,
-                                130
-                            );
+                            ZVideoRecordHelper.GetVideoPic(_tempVideoPathName, thumbnailPathName);
                             _videoInfo.FileGuid = Guid.NewGuid().ToString();
                             _videoInfo.IsUpload = false;
                             _videoInfo.Uploaded = 0;

XHWK.WKTool/Utils/ZVideoRecordHelper.cs

 using System;
+using System.Drawing.Imaging;
+using System.Drawing;
 using System.Runtime.InteropServices;
-
 using Accord.Video;
 using Accord.Video.FFMPEG;
 
 namespace XHWK.WKTool.Utils
 {
+    using System.Linq;
+
     public class ZVideoRecordHelper
     {
         public enum RecordState
         {
-            stop = 0,
-            start = 1,
-            pause = 2
+            Stop = 0,
+            Start = 1,
+            Pause = 2
         }
 
-        private RecordState _state = RecordState.stop;
+        private RecordState _state = RecordState.Stop;
 
-        private string _filePath = "";
-        private int _width = 0;
-        private int _height = 0;
+        private string _filePath;
+        private int _width;
+        private int _height;
 
         //录制帧率
         private int _rate = 5;
             _rate = rate;
             _quality = quality;
             _captureMouse = captureMouse;
-
-            _state = RecordState.pause;
+            _state = RecordState.Pause;
             try
             {
                 // 打开写入
         /// </summary>
         public bool StartRecordVideo()
         {
-            _state = RecordState.start;
+            _state = RecordState.Start;
             return true;
         }
 
         // 帧返回时绘制上鼠标
         private void VideoNewFrame(object sender, NewFrameEventArgs e)
         {
-            if (_state == RecordState.start)
+            if (_state == RecordState.Start)
             {
                 if (_captureMouse)
                 {
                     try
                     {
                         System.Windows.Forms.Cursor cur = new System.Windows.Forms.Cursor(pci.hCursor);
-                        cur.Draw(
+                        cur.Draw
+                        (
                             g,
-                            new System.Drawing.Rectangle(
+                            new System.Drawing.Rectangle
+                            (
                                 System.Windows.Forms.Cursor.Position.X - 10,
                                 System.Windows.Forms.Cursor.Position.Y - 10,
                                 cur.Size.Width,
                             )
                         );
                     }
-                    catch { }//打开任务管理器时会导致异常
+                    catch { } //打开任务管理器时会导致异常
                 }
                 videoWriter.WriteVideoFrame(e.Frame);
             }
         /// </summary>
         public void StopRecordVideo()
         {
-            _state = RecordState.stop;
+            _state = RecordState.Stop;
             // 停止
             videoStreamer.Stop();
 
         /// </summary>
         public void PauseRecordVideo()
         {
-            _state = RecordState.pause;
+            _state = RecordState.Pause;
         }
 
         /// <summary>
         /// </summary>
         public void ResumeRecordVideo()
         {
-            _state = RecordState.start;
+            _state = RecordState.Start;
+        }
+
+        /// <summary>
+        /// 生成缩略图
+        /// </summary>
+        /// <param name="mp4Path"></param>
+        /// <param name="picPath"></param>
+        public static void GetVideoPic(string mp4Path, string picPath)
+        {
+            using (var video = new VideoFileReader())
+            {
+                video.Open(mp4Path);
+                int frameNum = video.FrameCount > 3 ? 3 : 0;
+                using (var bmp = video.ReadVideoFrame(frameNum))
+                {
+                    SaveAsJpeg
+                    (
+                        bmp,
+                        picPath,
+                        90
+                    );
+                }
+                video.Close();
+            }
+        }
+
+        // 保存为jpeg格式，quality为图像质量（0-100）
+        public static void SaveAsJpeg
+        (
+            Bitmap bitmap,
+            string fileName,
+            int quality
+        )
+        {
+            var jpegEncoder = ImageCodecInfo.GetImageEncoders().First(codec => codec.FormatID == ImageFormat.Jpeg.Guid);
+            var encoderParameters = new EncoderParameters(1);
+            encoderParameters.Param[0] = new EncoderParameter(Encoder.Quality, quality);
+            bitmap.Save
+            (
+                fileName,
+                jpegEncoder,
+                encoderParameters
+            );
         }
     }
-}
+}

星火微课/星火微课-测试.iss

 
 #define MyAppName "星火微课测试版"  
 #define MyAppDir "xhwk_test"
-#define MyAppVersion "3.9.3"
+#define MyAppVersion "3.9.4"
 #define MyAppPublisher "河南星火燎原软件科技有限公司"
 #define MyAppURL "http://www.xhkjedu.com/"
 #define MySourcePath "D:\Project\CSharp\xh-wkclient\XHWK.WKTool\bin\x86\Debug\"