unity 调用外部相机拍照

using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using UnityEngine;

public class TakePhotoCamera : MonoBehaviour
{
    public static TakePhotoCamera instance;
    public byte[] imageTytes;
    //摄像头图像类，继承自texture
    public WebCamTexture tex;
    /// <summary>
    /// 图片保存路径
    /// </summary>
    public string picPath = "";
    private void Awake()
    {
        instance = this;
    }

    // Start is called before the first frame update
    void Start()
    {
        StartCoroutine(OpenCamera());
    }

    IEnumerator OpenCamera()
    {
        //等待用户允许访问
        yield return Application.RequestUserAuthorization(UserAuthorization.WebCam);
        //如果用户允许访问，开始获取图像        
        if (Application.HasUserAuthorization(UserAuthorization.WebCam))
        {
            //先获取设备
            WebCamDevice[] device = WebCamTexture.devices;
            string deviceName = device[0].name;
            //然后获取图像
            tex = new WebCamTexture(deviceName);
            //将获取的图像赋值
            // ma.material.mainTexture = tex;
            //开始实施获取
            tex.Play();
        }
    }

    public void TakingPhoto(string pictureType)
    {     
        Save(tex,pictureType);
    }
    
    public void Save(WebCamTexture t,string pictureType)
    {
        Texture2D t2d = new Texture2D(t.width, t.height, TextureFormat.ARGB32, true);
        //将WebCamTexture 的像素保存到texture2D中
        t2d.SetPixels(t.GetPixels());
        t2d.Apply();  
         imageTytes = t2d.EncodeToJPG();      
        picPath = Application.persistentDataPath + "/" + DateTime.Now.ToString("yyyy-MM-dd-hh-mm-ss") + ".jpg";
        File.WriteAllBytes(picPath, imageTytes);
    }
    void StopCamera()
    {
        //等待用户允许访问
        //Application.RequestUserAuthorization(UserAuthorization.WebCam);
        //如果用户允许访问，开始获取图像        
        if (Application.HasUserAuthorization(UserAuthorization.WebCam))
        {
            //先获取设备
            WebCamDevice[] device = WebCamTexture.devices;
            string deviceName = device[0].name;         
            tex.Stop();
        }
    }

    private void OnDisable()
    {
        StopCamera();
    }  
}