How to use External USB Camera with Android Tablet

Questions & Answers
1

I am try to use External Webcam camera attached to android tablet via OTG cable.

External Camera is not showing in webcam array .
I have also added Permissions in Android Manifest. but still no luck
Build never asks for usb external camera permission.

 // Addition in Android Manifest
 //<uses-feature android:name="android.hardware.camera.external" android:required="true"/>
 //<uses-feature android:name="android.hardware.usb.host" />  
// Addition in Android Manifest

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class phoneCamera : MonoBehaviour
{

    private bool camAvailable;
    private WebCamTexture backCam;
    private Texture defaultBackground;

    public RawImage background;
    


    // Use this for initialization
    void Start()
    {

        defaultBackground = background.texture;
        WebCamDevice[] devices = WebCamTexture.devices;

        if (devices.Length == 0)
        {
            Debug.Log("No Camera Detected");
            camAvailable = false;
            return;
        }

        for (int i = 0; i < devices.Length; i++)
        {
            if (!devices*.isFrontFacing)*

{
backCam = new WebCamTexture(devices*.name, Screen.width, Screen.height);*
}
}

if (backCam == null)
{
Debug.Log(“Unable to Find Back Camera”);
return;
}

backCam.Play();
background.texture = backCam;

camAvailable = true;

}
}
// devices.Length is always 2, Camera 0 and Camera 1

2

The external cameras are not detected by default hardware.camera package in android. You’ll need some native plugin to access it and then expose that to unity.

I have found the following open source project which does just this: https://github.com/TimGroeneboom/libuvc_android_unity

Hope it helps, others looking for same,