fix 前端实时人脸检测在win10上的效果不佳

src/features/OnlineExam/Examing/FaceTracking.vue

@@ -6,11 +6,34 @@
 import * as faceapi from "face-api.js";
 import { FACE_API_MODEL_PATH } from "@/constants/constants";
 
+const os = (function() {
+  const ua = navigator.userAgent.toLowerCase();
+  return {
+    isWin2K: /windows nt 5.0/.test(ua),
+    isXP: /windows nt 5.1/.test(ua),
+    isVista: /windows nt 6.0/.test(ua),
+    isWin7: /windows nt 6.1/.test(ua),
+    isWin8: /windows nt 6.2/.test(ua),
+    isWin81: /windows nt 6.3/.test(ua),
+    isWin10: /windows nt 10.0/.test(ua),
+  };
+})();
+
+// if (os.isWin7) alert("是win7");
+
+// if (os.isWin10) alert("是win10");
+
 function getFaceDetectorOptions() {
+  let inputSize = 320;
+  if (os.isWin7) {
+    inputSize = 256; // 在win7上无bug，速度快，效果较好
+  } else if (os.isWin10) {
+    inputSize = 320; // 在win10上，效果较好
+  }
   window.____hideMe =
     window.____hideMe ||
     new faceapi.TinyFaceDetectorOptions({
-      inputSize: 256,
+      inputSize: inputSize,
       scoreThreshold: 0.5,
     });
   return window.____hideMe;