打印摄像头设备能力

src/components/FaceRecognition/FaceRecognition.vue

@@ -105,6 +105,11 @@ export default {
       if (navigator.mediaDevices && navigator.mediaDevices.getUserMedia) {
         try {
           console.log("启动摄像头");
+          console.log({
+            getSupportedConstraints:
+              navigator.mediaDevices.getSupportedConstraints &&
+              navigator.mediaDevices.getSupportedConstraints(),
+          });
           const stream = await navigator.mediaDevices.getUserMedia({
             video: {
               facingMode: "user",
@@ -115,6 +120,12 @@ export default {
             },
           });
           if (stream) {
+            const vt0 = stream.getVideoTracks()[0];
+            console.log({
+              getCapabilities: vt0.getCapabilities && vt0.getCapabilities(),
+              getConstraints: vt0.getConstraints && vt0.getConstraints(),
+              getSettings: vt0.getSettings && vt0.getSettings(),
+            });
             video.srcObject = stream;
             try {
               await video.play();
@@ -324,7 +335,7 @@ export default {
         var context = canvas.getContext("2d");
         context.drawImage(video, 0, 0, 220, 165);
 
-        canvas.toBlob(resolve, "image/jpeg", 0.95);
+        canvas.toBlob(resolve, "image/png", 0.95);
       });
     },
     async uploadToServer(captureBlob) {
@@ -350,7 +361,7 @@ export default {
         console.log(fileMd5);
 
         const params = new URLSearchParams();
-        params.append("fileSuffix", "jpg");
+        params.append("fileSuffix", "png");
         params.append("fileMd5", fileMd5);
         const res = await this.$http.get(
           "/api/ecs_oe_student/examControl/getCapturePhotoUpYunSign?" + params