From d0ad840ef40aea9575aa89904bc77a08d51e7de8 Mon Sep 17 00:00:00 2001
From: Nicolas Mowen <nickmowen213@gmail.com>
Date: Fri, 20 Dec 2024 08:17:51 -0600
Subject: [PATCH] Enable temporary caching of camera images to improve
 responsiveness of UI (#15614)

---
 .../api/defs/query/media_query_parameters.py  |  1 +
 frigate/api/media.py                          | 18 ++++++++++----
 .../camera/AutoUpdatingCameraImage.tsx        | 24 +++++++++++++++++--
 web/src/components/player/LivePlayer.tsx      |  3 ++-
 4 files changed, 39 insertions(+), 7 deletions(-)

diff --git a/frigate/api/defs/query/media_query_parameters.py b/frigate/api/defs/query/media_query_parameters.py
index b7df85d30..bcccb99bf 100644
--- a/frigate/api/defs/query/media_query_parameters.py
+++ b/frigate/api/defs/query/media_query_parameters.py
@@ -20,6 +20,7 @@ class MediaLatestFrameQueryParams(BaseModel):
     regions: Optional[int] = None
     quality: Optional[int] = 70
     height: Optional[int] = None
+    store: Optional[int] = None
 
 
 class MediaEventsSnapshotQueryParams(BaseModel):
diff --git a/frigate/api/media.py b/frigate/api/media.py
index b5f3ba703..6cd11b30e 100644
--- a/frigate/api/media.py
+++ b/frigate/api/media.py
@@ -182,11 +182,16 @@ def latest_frame(
 
         frame = cv2.resize(frame, dsize=(width, height), interpolation=cv2.INTER_AREA)
 
-        ret, img = cv2.imencode(f".{extension}", frame, quality_params)
+        _, img = cv2.imencode(f".{extension}", frame, quality_params)
         return Response(
             content=img.tobytes(),
             media_type=f"image/{mime_type}",
-            headers={"Content-Type": f"image/{mime_type}", "Cache-Control": "no-store"},
+            headers={
+                "Content-Type": f"image/{mime_type}",
+                "Cache-Control": "no-store"
+                if not params.store
+                else "private, max-age=60",
+            },
         )
     elif camera_name == "birdseye" and request.app.frigate_config.birdseye.restream:
         frame = cv2.cvtColor(
@@ -199,11 +204,16 @@ def latest_frame(
 
         frame = cv2.resize(frame, dsize=(width, height), interpolation=cv2.INTER_AREA)
 
-        ret, img = cv2.imencode(f".{extension}", frame, quality_params)
+        _, img = cv2.imencode(f".{extension}", frame, quality_params)
         return Response(
             content=img.tobytes(),
             media_type=f"image/{mime_type}",
-            headers={"Content-Type": f"image/{mime_type}", "Cache-Control": "no-store"},
+            headers={
+                "Content-Type": f"image/{mime_type}",
+                "Cache-Control": "no-store"
+                if not params.store
+                else "private, max-age=60",
+            },
         )
     else:
         return JSONResponse(
diff --git a/web/src/components/camera/AutoUpdatingCameraImage.tsx b/web/src/components/camera/AutoUpdatingCameraImage.tsx
index ee0f6eccc..d97a9214a 100644
--- a/web/src/components/camera/AutoUpdatingCameraImage.tsx
+++ b/web/src/components/camera/AutoUpdatingCameraImage.tsx
@@ -1,4 +1,4 @@
-import { useCallback, useEffect, useRef, useState } from "react";
+import { useCallback, useEffect, useMemo, useRef, useState } from "react";
 import CameraImage from "./CameraImage";
 
 type AutoUpdatingCameraImageProps = {
@@ -8,6 +8,7 @@ type AutoUpdatingCameraImageProps = {
   className?: string;
   cameraClasses?: string;
   reloadInterval?: number;
+  periodicCache?: boolean;
 };
 
 const MIN_LOAD_TIMEOUT_MS = 200;
@@ -19,6 +20,7 @@ export default function AutoUpdatingCameraImage({
   className,
   cameraClasses,
   reloadInterval = MIN_LOAD_TIMEOUT_MS,
+  periodicCache = false,
 }: AutoUpdatingCameraImageProps) {
   const [key, setKey] = useState(Date.now());
   const [fps, setFps] = useState<string>("0");
@@ -42,6 +44,8 @@ export default function AutoUpdatingCameraImage({
   }, [reloadInterval]);
 
   const handleLoad = useCallback(() => {
+    setIsCached(true);
+
     if (reloadInterval == -1) {
       return;
     }
@@ -66,12 +70,28 @@ export default function AutoUpdatingCameraImage({
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [key, setFps]);
 
+  // periodic cache to reduce loading indicator
+
+  const [isCached, setIsCached] = useState(false);
+
+  const cacheKey = useMemo(() => {
+    let baseParam = "";
+
+    if (periodicCache && !isCached) {
+      baseParam = "store=1";
+    } else {
+      baseParam = `cache=${key}`;
+    }
+
+    return `${baseParam}${searchParams ? `&${searchParams}` : ""}`;
+  }, [isCached, periodicCache, key, searchParams]);
+
   return (
     <div className={className}>
       <CameraImage
         camera={camera}
         onload={handleLoad}
-        searchParams={`cache=${key}${searchParams ? `&${searchParams}` : ""}`}
+        searchParams={cacheKey}
         className={cameraClasses}
       />
       {showFps ? <span className="text-xs">Displaying at {fps}fps</span> : null}
diff --git a/web/src/components/player/LivePlayer.tsx b/web/src/components/player/LivePlayer.tsx
index 8038812db..abf908baa 100644
--- a/web/src/components/player/LivePlayer.tsx
+++ b/web/src/components/player/LivePlayer.tsx
@@ -294,10 +294,11 @@ export default function LivePlayer({
       >
         <AutoUpdatingCameraImage
           className="size-full"
+          cameraClasses="relative size-full flex justify-center"
           camera={cameraConfig.name}
           showFps={false}
           reloadInterval={stillReloadInterval}
-          cameraClasses="relative size-full flex justify-center"
+          periodicCache
         />
       </div>