如何在react native中加密SD卡中的视频文件

import CryptoJS from 'crypto-js';

const encryptFile = (filePath, key, iv) => {
  const fileContent = // 读取视频文件内容
  const encrypted = CryptoJS.AES.encrypt(fileContent, key, { iv });
  // 将加密后的内容写入文件
};

import { Platform, PermissionsAndroid } from 'react-native';
import RNFS from 'react-native-fs';

const encryptVideo = async () => {
  try {
    const granted = await PermissionsAndroid.request(
      PermissionsAndroid.PERMISSIONS.READ_EXTERNAL_STORAGE,
      {
        title: 'Permission',
        message: 'Allow access to your storage',
        buttonNeutral: 'Ask Me Later',
        buttonNegative: 'Cancel',
        buttonPositive: 'OK',
      },
    );
    if (granted === PermissionsAndroid.RESULTS.GRANTED) {
      const filePath = // 获取视频文件路径
      const key = // 生成密钥
      const iv = // 生成初始化向量
      encryptFile(filePath, key, iv);
    } else {
      console.log('Permission denied');
    }
  } catch (err) {
    console.warn(err);
  }
};