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Real-time body pose detection for React Native & Expo using Google MediaPipe. 33 body landmarks, VisionCamera frame processors, GPU acceleration, photo detection and an Expo config plugin. New Architecture (TurboModules).

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react-native-mediapipe-posedetection

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High-performance pose detection for React Native using Google's MediaPipe models with optimized frame processing for smooth real-time tracking.

You can find the package on npm: react-native-mediapipe-posedetection

📖 Read the full documentation →

⚠️ New Architecture Required

This library only supports React Native's New Architecture (Turbo Modules). You must enable the New Architecture in your app to use this library.

Features

  • ✨ Real-time pose detection via react-native-vision-camera
  • 🎯 33 pose landmarks per detected person
  • 🚀 Optimized for performance (configurable FPS limit, built-in event throttling on iOS)
  • 📱 iOS & Android support
  • 🔥 GPU acceleration support
  • 🎨 Static image detection support
  • 🪝 Easy-to-use React hooks

Requirements

  • React Native: 0.74.0 or higher
  • New Architecture: Must be enabled
  • iOS: the minimum iOS version supported by your React Native version
  • Android: API 24+
  • Dependencies:
    • react-native-vision-camera ^4.0.0 (for real-time detection)
    • react-native-worklets-core ^1.0.0 (for frame processing)

Installation

npm install react-native-mediapipe-posedetection react-native-vision-camera react-native-worklets-core
# or
yarn add react-native-mediapipe-posedetection react-native-vision-camera react-native-worklets-core

Expo Configuration

If you are using Expo, you can use the built-in config plugin to automatically copy your MediaPipe model files to the native Android and iOS projects during prebuild.

  1. Add your model files (e.g., pose_landmarker_lite.task) to a directory in your project (e.g., ./assets/models/).
  2. Update your app.json or app.config.js:
{
  "expo": {
    "plugins": [
      [
        "react-native-mediapipe-posedetection",
        {
          "assetsPaths": ["./assets/models/"]
        }
      ]
    ]
  }
}

This plugin will copy all files from the specified assetsPaths to:

  • Android: android/app/src/main/assets/
  • iOS: The root of the Xcode project (and add them to the build resources).

Note: The assetsPaths are relative to your project root. You can also pass ignoredPattern (a regex string) to skip files, e.g. "\\.md$".

Enable New Architecture

If you haven't already enabled the New Architecture in your React Native app:

Android

In your android/gradle.properties:

newArchEnabled=true

iOS

In your ios/Podfile:

use_frameworks! :linkage => :static
$RNNewArchEnabled = true

Then reinstall pods:

cd ios && pod install

iOS Setup

  1. Download the MediaPipe pose landmarker model (e.g., pose_landmarker_lite.task)
  2. Add it to your Xcode project
  3. Ensure it's included in "Copy Bundle Resources" build phase

Android Setup

The MediaPipe dependencies are automatically included. Place your model file in android/app/src/main/assets/.

Usage

Real-time Pose Detection with Camera

import {
  usePoseDetection,
  RunningMode,
  Delegate,
  KnownPoseLandmarks,
} from 'react-native-mediapipe-posedetection';
import { Camera, useCameraDevice } from 'react-native-vision-camera';

function PoseDetectionScreen() {
  const device = useCameraDevice('back');

  const poseDetection = usePoseDetection(
    {
      onResults: (result) => {
        // result.results[0].landmarks is an array of people, each with 33 landmarks
        const people = result.results[0]?.landmarks ?? [];
        console.log('Number of poses:', people.length);
        const firstPerson = people[0];
        if (firstPerson) {
          const nose = firstPerson[KnownPoseLandmarks.nose];
          console.log('Nose position:', nose.x, nose.y);
        }
      },
      onError: (error) => {
        console.error('Detection error:', error.message);
      },
    },
    RunningMode.LIVE_STREAM,
    'pose_landmarker_lite.task',
    {
      numPoses: 1,
      minPoseDetectionConfidence: 0.5,
      minPosePresenceConfidence: 0.5,
      minTrackingConfidence: 0.5,
      delegate: Delegate.GPU,
    }
  );

  if (!device) return null;

  return (
    <Camera
      style={{ flex: 1 }}
      device={device}
      isActive={true}
      pixelFormat="rgb"
      frameProcessor={poseDetection.frameProcessor}
      onLayout={poseDetection.cameraViewLayoutChangeHandler}
      onOutputOrientationChanged={poseDetection.cameraOrientationChangedHandler}
    />
  );
}

Static Image Detection

import {
  PoseDetectionOnImage,
  Delegate,
} from 'react-native-mediapipe-posedetection';

async function detectPoseInImage(imagePath: string) {
  const result = await PoseDetectionOnImage(
    imagePath,
    'pose_landmarker_lite.task',
    {
      numPoses: 2, // Detect up to 2 people
      minPoseDetectionConfidence: 0.5,
      delegate: Delegate.GPU,
    }
  );

  console.log('Detected poses:', result.results[0]?.landmarks.length ?? 0);
  console.log('Inference time:', result.inferenceTime, 'ms');
}

Using the MediapipeCamera Component

For a simpler setup, pass the result of usePoseDetection to the provided MediapipeCamera component. It wires up the frame processor, layout, orientation and camera device handlers for you:

import {
  MediapipeCamera,
  usePoseDetection,
  RunningMode,
} from 'react-native-mediapipe-posedetection';

function App() {
  const solution = usePoseDetection(
    {
      onResults: (result) => {
        console.log('Pose detected:', result.results[0]?.landmarks);
      },
      onError: (error) => console.warn(error.message),
    },
    RunningMode.LIVE_STREAM,
    'pose_landmarker_lite.task',
    { numPoses: 1, minPoseDetectionConfidence: 0.5 }
  );

  return (
    <MediapipeCamera
      style={{ flex: 1 }}
      solution={solution}
      activeCamera="back" // 'front' (default) | 'back'
      resizeMode="cover" // 'cover' (default) | 'contain'
    />
  );
}

API Reference

usePoseDetection(callbacks, runningMode, model, options)

Hook for real-time pose detection.

Parameters:

  • callbacks: DetectionCallbacks<PoseDetectionResultBundle>

    • onResults: (result: PoseDetectionResultBundle, viewCoordinator: ViewCoordinator) => void - Called when poses are detected. viewCoordinator converts normalized landmarks to screen coordinates
    • onError: (error: DetectionError) => void - Called on detection errors
  • runningMode: RunningMode

    • RunningMode.LIVE_STREAM - For camera/video input
    • RunningMode.VIDEO - For video file processing
    • RunningMode.IMAGE - For static images (use PoseDetectionOnImage instead)
  • model: string - Path to MediaPipe model file (e.g., 'pose_landmarker_lite.task')

  • options: Partial<PoseDetectionOptions> (optional)

    • numPoses: number - Maximum number of poses to detect (default: 1)
    • minPoseDetectionConfidence: number - min confidence threshold (default: 0.5)
    • minPosePresenceConfidence: number - min presence threshold (default: 0.5)
    • minTrackingConfidence: number - min tracking threshold (default: 0.5)
    • shouldOutputSegmentationMasks: boolean - Include segmentation masks (default: false)
    • delegate: Delegate.CPU | Delegate.GPU - Processing delegate (default: GPU)
    • mirrorMode: 'no-mirror' | 'mirror' | 'mirror-front-only' - Camera mirroring (default: 'mirror-front-only' on Android, 'no-mirror' on iOS)
    • forceCameraOrientation / forceOutputOrientation: ImageOrientation - Override detected orientations
    • fpsMode: 'none' | number - Additional FPS throttling (default: 'none')

Returns: MediaPipeSolution

  • frameProcessor: VisionCamera frame processor
  • cameraViewLayoutChangeHandler: Layout change handler
  • cameraDeviceChangeHandler: Camera device change handler
  • cameraOrientationChangedHandler: Orientation change handler
  • resizeModeChangeHandler: Resize mode handler
  • cameraViewDimensions: Current camera view dimensions

PoseDetectionOnImage(imagePath, model, options)

Detect poses in a static image.

Parameters:

  • imagePath: string - Path to the image file
  • model: string - Path to MediaPipe model file
  • options: Same as usePoseDetection options

Returns: Promise<PoseDetectionResultBundle>

Result Structure

interface PoseDetectionResultBundle {
  results: PoseLandmarkerResult[]; // One entry for live camera frames and single images
  inferenceTime: number; // Milliseconds
  inputImageWidth: number;
  inputImageHeight: number;
}

interface PoseLandmarkerResult {
  landmarks: Landmark[][]; // [person][landmarkIndex], 33 landmarks per person, normalized
  worldLandmarks: Landmark[][]; // [person][landmarkIndex], 3D world coordinates in meters
  segmentationMasks: Mask[];
}

interface Landmark {
  x: number; // Normalized 0-1
  y: number; // Normalized 0-1
  z: number; // Depth (relative)
  visibility?: number; // Confidence 0-1
  presence?: number; // Presence confidence 0-1
}

Landmark Indices

Use KnownPoseLandmarks for easy landmark access:

import { KnownPoseLandmarks } from 'react-native-mediapipe-posedetection';

const landmarks = result.results[0]?.landmarks[0]; // first person
const nose = landmarks[KnownPoseLandmarks.nose];
const leftShoulder = landmarks[KnownPoseLandmarks.leftShoulder];
const rightWrist = landmarks[KnownPoseLandmarks.rightWrist];

Available landmarks:

  • Face: nose, leftEye, rightEye, leftEar, rightEar, mouthLeft, mouthRight
  • Upper body: leftShoulder, rightShoulder, leftElbow, rightElbow, leftWrist, rightWrist
  • Hands: leftPinky, rightPinky, leftIndex, rightIndex, leftThumb, rightThumb
  • Lower body: leftHip, rightHip, leftKnee, rightKnee, leftAnkle, rightAnkle
  • Feet: leftHeel, rightHeel, leftFootIndex, rightFootIndex

Performance Optimizations

This library includes critical performance optimizations for React Native's new architecture:

⚡ Event Throttling on iOS

On iOS, the native module caps result events sent to JavaScript at ~15 per second to keep memory stable during long sessions. This needs no configuration. Android delivers every result, so setting fpsMode (below) matters more there.

🎯 FPS Control

Limit how many frames are sent to MediaPipe with the fpsMode option. 10–15 FPS is enough for smooth tracking in most apps and saves battery:

usePoseDetection(callbacks, RunningMode.LIVE_STREAM, 'model.task', {
  fpsMode: 10, // Process frames at 10 FPS
});

Migration from Old Architecture

If you were using a previous version that supported the Bridge architecture:

  1. Upgrade React Native to 0.74.0 or higher

  2. Enable New Architecture (see installation instructions)

  3. Rebuild your app completely:

    # iOS
    cd ios && pod install && cd ..
    
    # Android
    cd android && ./gradlew clean && cd ..

The API remains the same, so your application code shouldn't need changes.

Troubleshooting

"MediapipePosedetection TurboModule is not available"

Cause: New Architecture is not enabled or not properly configured.

Solution:

  1. Verify newArchEnabled=true in android/gradle.properties
  2. Verify $RNNewArchEnabled = true in ios/Podfile
  3. Clean and rebuild your app
  4. Ensure you're using React Native 0.74.0+

"Failed to create detector"

Cause: Model file not found or invalid configuration.

Solution:

  1. Verify the model file path is correct
  2. Ensure the model file is included in your app bundle
  3. Check that the model file is a valid MediaPipe pose landmarker model

Memory Warnings / Crashes on iOS

Solution:

  1. Ensure you're on the latest version
  2. Set fpsMode: 15 (or lower)
  3. Reduce numPoses to 1
  4. Set shouldOutputSegmentationMasks: false
  5. Use Delegate.CPU instead of Delegate.GPU if GPU memory is limited

Poor Performance

Solutions:

  1. Use pose_landmarker_lite.task instead of pose_landmarker_full.task
  2. Set fpsMode: 10 for lower frame processing
  3. Reduce numPoses if you don't need to detect multiple people
  4. Enable GPU acceleration: delegate: Delegate.GPU

Example App

Check out the example directory for a complete working app demonstrating:

  • Real-time pose detection
  • Pose landmark visualization
  • Camera controls
  • Performance optimization

Run the example:

cd example
yarn install
yarn ios  # or yarn android

Contributing

See the contributing guide to learn how to contribute to the repository and the development workflow.

Credits

This library is based on the work from react-native-mediapipe by cdiddy77. The pose detection module codes were taken from this repository and upgraded to support React Native's New Architecture (Turbo Modules).

License

MIT © EndLess728


Made with create-react-native-library

About

Real-time body pose detection for React Native & Expo using Google MediaPipe. 33 body landmarks, VisionCamera frame processors, GPU acceleration, photo detection and an Expo config plugin. New Architecture (TurboModules).

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