flutter_uvc_camera

A Flutter plugin based on AndroidUSBCamera to enable Flutter apps to use external cameras.

pub：flutter_uvc_camera

Preface

• Only supports Android
• Android 10 need to reduce targetSdkVersion to 27
• Discovering problematic models：Redmi Note 10

Getting Started

1. Add Dependency

Add the flutter_uvc_camera plugin dependency to your Flutter project's pubspec.yaml file:

dependencies:
  flutter_uvc_camera: last_version

2. Configure Android Project

Before using this plugin, some configurations are needed for the Android project.

Add Permissions

Add the following permissions to the AndroidManifest.xml file of your Android project:

   <uses-permission android:name="android.permission.USB_PERMISSION" />
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
    <uses-permission android:name="android.permission.CAMERA"/>
    <uses-permission android:name="android.permission.RECORD_AUDIO"/>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
    <uses-feature android:name="android.hardware.usb.host" />
    <uses-feature android:name="android.hardware.camera"/>
    <uses-feature android:name="android.hardware.camera.autofocus"/>
    <!-- Add other necessary permissions here -->

Add maven { url "https://jitpack.io" } in android/build.gradle:

allprojects {
    repositories {
        /// other repositories
        maven { url "https://jitpack.io" }
    }
}

Add Intent Filter and Meta-data for Device Insertion Detection, Plug-in Monitoring, and Recognition of Opening Applications

Android documents USB host overview

Add an action for USB device connection in the intent-filter of mainActivity, and reference the corresponding XML file in meta-data:

<intent-filter>
    <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
</intent-filter>
<meta-data
    android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
    android:resource="@xml/device_filter" />

<?xml version="1.0" encoding="utf-8"?>

<resources>
    <usb-device vendor-id="1234" product-id="5678" class="255" subclass="66" protocol="1" />
</resources>

3. Usage Example

import 'package:flutter/material.dart';
import 'package:flutter_uvc_camera/uvc_camera_controller.dart';
import 'package:flutter_uvc_camera/uvc_camera_view.dart';

class CameraTest extends StatefulWidget {
  const CameraTest({super.key});

  @override
  State<CameraTest> createState() => _CameraTestState();
}

class _CameraTestState extends State<CameraTest> {
  UVCCameraController? cameraController;
  
  @override
  void initState() {
    super.initState();
    cameraController = UVCCameraController();
    cameraController?.msgCallback = (state) {
      showCustomToast(state);
    };
  }
  
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('UVC Camera Example'),
        ),
        body: Center(
          child: UVCCameraView(
              cameraController: cameraController!,
              width: 300,
              height: 300),
        ),
      ),
    );
  }
}

Problems

add proguard-rules.pro

flutter run release encounters a NoSuchMethodError

• example/android/app/build.gradle

 buildTypes {
      release {
        <!--   ...-->
        proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        minifyEnabled true
    }
}

• example/android/app/proguard-rules.pro

 -keep class com.jiangdg.uvc.UVCCamera {
        native <methods>;
  long mNativePtr;
  }
  -keep class com.jiangdg.uvc.IStatusCallback {
  *;
  }
  -keep interface com.jiangdg.uvc.IButtonCallback {
  *;
  }

Notes

• Ensure that the required permissions are configured before using the plugin, otherwise the plugin may not function properly.
• The plugin currently supports using external cameras in Flutter projects but may have some limitations and compatibility issues. Please test and adjust the plugin according to your needs.

Issue Reporting

If you encounter any problems or have any suggestions during usage, please report them on GitHub Issues .