新增 Mjpegplayer 用来播放 Web 流

SHH.MjpegPlayer/Core/ImageChannels.cs

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+using Core.WcfProtocol;
+using System.Collections.Concurrent;
+
+namespace SHH.MjpegPlayer
+{
+    /// <summary>图片通道集合</summary>
+    public class ImageChannels
+    {
+        #region Channels
+
+        /// <summary>
+        /// 通道信息 (线程安全版本)
+        /// </summary>
+        // [修复] 使用 ConcurrentDictionary 替代 Dictionary，防止多线程读写（如推流和接收图片同时进行）时崩溃
+        public ConcurrentDictionary<string, ImageChannel> Channels { get; set; }
+            = new ConcurrentDictionary<string, ImageChannel>();
+
+        #endregion
+
+        #region Do
+
+        /// <summary>
+        /// 处置图片
+        /// </summary>
+        /// <param name="req"></param>
+        /// <param name="key"></param>
+        public ImageChannel? Do(UploadImageRequest req, string key)
+        {
+            // [修复] 使用 GetOrAdd 原子操作，无需 lock，彻底解决并发冲突
+            // 如果 key 不存在，则创建新通道；如果存在，则返回现有通道
+            var chn = Channels.GetOrAdd(key, k => new ImageChannel
+            {
+                DeviceId = req.Id,
+                Name = req.Name,
+                Type = req.Type,
+            });
+
+            // 更新指定信息 (直接属性赋值是原子性的，无需锁)
+            chn.IpAddress = req.IpAddress;
+            chn.ProcId = req.ProcId;
+            chn.ImageWidth = req.ImageWidth;
+            chn.ImageHeight = req.ImageHeight;
+            chn.UpdateTime = req.Time;
+
+            return chn;
+        }
+
+        #endregion
+
+        #region Get
+
+        /// <summary>
+        /// 获取通道信息
+        /// </summary>
+        /// <param name="deviceId"></param>
+        /// <param name="aiTypeCode"></param>
+        /// <returns></returns>
+        public ImageChannel? Get(string deviceId, string aiTypeCode)
+        {
+            string key = $"{deviceId}#{aiTypeCode}";
+
+            // [修复] ConcurrentDictionary 读取原本就是线程安全的
+            if (Channels.TryGetValue(key, out var val))
+            {
+                return val;
+            }
+            return null;
+        }
+
+        #endregion
+    }
+}