Render the JSMPEG spinner until the last possible moment.

package.json

@@ -22,7 +22,7 @@
     "@material/rtl": "^13.0.0",
     "custom-card-helpers": "^1.8.0",
     "dayjs": "^1.10.7",
-    "embla-carousel": "^5.0.1",
+    "embla-carousel": "^6.1.0",
     "home-assistant-js-websocket": "^5.11.1",
     "lit": "^2.0.2",
     "lodash-es": "^4.17.21",

src/components/live.ts

@@ -754,46 +754,46 @@ export class FrigateCardLiveJSMPEG extends LitElement {
 
   /**
    * Create a JSMPEG player.
+   * @param url The URL for the player to connect to.
    * @returns A JSMPEG player.
    */
-  protected _createJSMPEGPlayer(url: string): JSMpeg.VideoElement {
-    let videoDecoded = false;
-
-    const jsmpegOptions = {
-      pauseWhenHidden: false,
-      protocols: [],
-      audio: false,
-      videoBufferSize: 1024 * 1024 * 4,
-      onVideoDecode: () => {
-        // This is the only callback that is called after the dimensions
-        // are available. It's called on every frame decode, so just
-        // ignore any subsequent calls.
-        if (!videoDecoded && this._jsmpegCanvasElement) {
-          videoDecoded = true;
-          dispatchMediaShowEvent(this, this._jsmpegCanvasElement);
-        }
-      },
-    };
-
-    // Override with user-specified options.
-    Object.assign(jsmpegOptions, this.jsmpegConfig?.options);
-
-    return new JSMpeg.VideoElement(
-      this,
-      url,
-      {
-        canvas: this._jsmpegCanvasElement,
-        hooks: {
-          play: () => {
-            dispatchPlayEvent(this);
-          },
-          pause: () => {
-            dispatchPauseEvent(this);
+  protected async _createJSMPEGPlayer(url: string): Promise<JSMpeg.VideoElement> {
+    return new Promise<JSMpeg.VideoElement>((resolve) => {
+      let videoDecoded = false;
+      const player = new JSMpeg.VideoElement(
+        this,
+        url,
+        {
+          canvas: this._jsmpegCanvasElement,
+          hooks: {
+            play: () => {
+              dispatchPlayEvent(this);
+            },
+            pause: () => {
+              dispatchPauseEvent(this);
+            },
           },
         },
-      },
-      jsmpegOptions,
-    );
+        {
+          pauseWhenHidden: false,
+          protocols: [],
+          audio: false,
+          videoBufferSize: 1024 * 1024 * 4,
+          // Override with user-specified options.
+          ...this.jsmpegConfig?.options,
+          onVideoDecode: () => {
+            // This is the only callback that is called after the dimensions
+            // are available. It's called on every frame decode, so just
+            // ignore any subsequent calls.
+            if (!videoDecoded && this._jsmpegCanvasElement) {
+              videoDecoded = true;
+              dispatchMediaShowEvent(this, this._jsmpegCanvasElement);
+              resolve(player);
+            }
+          },
+        },
+      );
+    });
   }
 
   /**
@@ -856,8 +856,7 @@ export class FrigateCardLiveJSMPEG extends LitElement {
 
     const url = await this._getURL();
     if (url) {
-      this._jsmpegVideoPlayer = this._createJSMPEGPlayer(url);
-
+      this._jsmpegVideoPlayer = await this._createJSMPEGPlayer(url);
       this._refreshPlayerTimerID = window.setTimeout(() => {
         this.requestUpdate();
       }, (URL_SIGN_EXPIRY_SECONDS - URL_SIGN_REFRESH_THRESHOLD_SECONDS) * 1000);

src/components/media-carousel.ts

@@ -110,7 +110,7 @@ export class FrigateCardMediaCarousel extends FrigateCardCarousel {
     if (!this._carousel) {
       return;
     }
-    this._carousel.containerNode().style.removeProperty('max-height')
+    this._carousel.containerNode().style.removeProperty('max-height');
   }
 
   /**
@@ -119,20 +119,24 @@ export class FrigateCardMediaCarousel extends FrigateCardCarousel {
    * different aspect ratios).
    */
   protected _adaptiveHeightSetHandler(): void {
-    if (!this._carousel) {
-      return;
-    }
-    const slides = this._carousel.slideNodes();
-    const heights = this._carousel.slidesInView(true).map((index) => {
-      const firstChild = slides[index].querySelector("*");
-      return firstChild ? firstChild.getBoundingClientRect().height : 0;
-    })
-    const targetHeight = Math.max(...heights);
-    if (targetHeight > 0) {
-      this._carousel.containerNode().style.maxHeight = `${targetHeight}px`;
-    } else {
-      this._carousel.containerNode().style.removeProperty('max-height')
-    }
+    // Don't gather slide heights until the next browser re-paint to ensure the
+    // measured heights are correct on the media that has (potentially) just
+    // loaded.
+    window.requestAnimationFrame(() => {
+      if (!this._carousel) {
+        return;
+      }
+      const slides = this._carousel.slideNodes();
+      const heights = this._carousel.slidesInView(true).map((index) => {
+        return slides[index].getBoundingClientRect().height;
+      });
+      const targetHeight = Math.max(...heights);
+      if (targetHeight > 0) {
+        this._carousel.containerNode().style.maxHeight = `${targetHeight}px`;
+      } else {
+        this._carousel.containerNode().style.removeProperty('max-height');
+      }
+    });
   }
 
   /**

src/scss/media-carousel.scss

@@ -2,6 +2,12 @@
   --video-max-height: none;
 }
 
+
+.embla__container {
+  // To support adaptive height animations.
+  transition: max-height 0.5s ease;
+}
+
 .embla__slide {
   flex: 0 0 100%;
 }