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Displaying the current time

When rendering a <Player> in your app, special considerations must be taken to prevent constant re-renders of the app or <Player> if the time changes.

This is why the useCurrentFrame() hook does not work outside a composition.

danger

Do not put this hook into the same component in which the <Player> is rendered, otherwise you'll see constant re-renders. Instead, put it inside a component that is rendered adjacent to the component in which the Player is rendered.

Synchronizing a component with the Player time

If you want to display a component that synchronizes with the time of the player, for example the cursor of a timeline component or a custom time display, you can use the following hook:

use-current-player-frame.ts
tsx
import { CallbackListener, PlayerRef } from "@remotion/player";
import { useCallback, useSyncExternalStore } from "react";
 
export const useCurrentPlayerFrame = (ref: React.RefObject<PlayerRef>) => {
const subscribe = useCallback(
(onStoreChange: (newVal: number) => void) => {
const { current } = ref;
if (!current) {
return () => undefined;
}
const updater: CallbackListener<"frameupdate"> = ({ detail }) => {
onStoreChange(detail.frame);
};
current.addEventListener("frameupdate", updater);
return () => {
current.removeEventListener("frameupdate", updater);
};
},
[ref]
);
 
const data = useSyncExternalStore<number>(
subscribe,
() => ref.current?.getCurrentFrame() ?? 0,
() => 0
);
 
return data;
};
use-current-player-frame.ts
tsx
import { CallbackListener, PlayerRef } from "@remotion/player";
import { useCallback, useSyncExternalStore } from "react";
 
export const useCurrentPlayerFrame = (ref: React.RefObject<PlayerRef>) => {
const subscribe = useCallback(
(onStoreChange: (newVal: number) => void) => {
const { current } = ref;
if (!current) {
return () => undefined;
}
const updater: CallbackListener<"frameupdate"> = ({ detail }) => {
onStoreChange(detail.frame);
};
current.addEventListener("frameupdate", updater);
return () => {
current.removeEventListener("frameupdate", updater);
};
},
[ref]
);
 
const data = useSyncExternalStore<number>(
subscribe,
() => ref.current?.getCurrentFrame() ?? 0,
() => 0
);
 
return data;
};

Usage example

Add a ref to a React Player and pass it to another component:

tsx
import { Player, PlayerRef } from "@remotion/player";
import { useRef } from "react";
import { MyVideo } from "./remotion/MyVideo";
import { TimeDisplay } from "./remotion/TimeDisplay";
 
export const App: React.FC = () => {
const playerRef = useRef<PlayerRef>(null);
 
return (
<>
<Player
ref={playerRef}
component={MyVideo}
durationInFrames={120}
compositionWidth={1920}
compositionHeight={1080}
fps={30}
/>
<TimeDisplay playerRef={playerRef} />
</>
);
};
tsx
import { Player, PlayerRef } from "@remotion/player";
import { useRef } from "react";
import { MyVideo } from "./remotion/MyVideo";
import { TimeDisplay } from "./remotion/TimeDisplay";
 
export const App: React.FC = () => {
const playerRef = useRef<PlayerRef>(null);
 
return (
<>
<Player
ref={playerRef}
component={MyVideo}
durationInFrames={120}
compositionWidth={1920}
compositionHeight={1080}
fps={30}
/>
<TimeDisplay playerRef={playerRef} />
</>
);
};

This is how a component could access the current time:

TimeDisplay.tsx
tsx
import React from "react";
import { PlayerRef } from "@remotion/player";
import { useCurrentPlayerFrame } from "./use-current-player-frame";
 
export const TimeDisplay: React.FC<{
playerRef: React.RefObject<PlayerRef>;
}> = ({ playerRef }) => {
const frame = useCurrentPlayerFrame(playerRef);
 
return <div>current frame: {frame}</div>;
};
TimeDisplay.tsx
tsx
import React from "react";
import { PlayerRef } from "@remotion/player";
import { useCurrentPlayerFrame } from "./use-current-player-frame";
 
export const TimeDisplay: React.FC<{
playerRef: React.RefObject<PlayerRef>;
}> = ({ playerRef }) => {
const frame = useCurrentPlayerFrame(playerRef);
 
return <div>current frame: {frame}</div>;
};

This approach is efficient, because only the video itself and the component relying on the time are re-rendering, but the <App> component is not.