要保护Android原始文件夹中的视频，可以使用以下代码示例：

1. 首先，在AndroidManifest.xml文件中添加以下权限：

2. 创建一个名为FileUtils.java的工具类，其中包含以下方法：

import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Build;
import android.os.Environment;
import android.provider.MediaStore;

import androidx.core.content.FileProvider;

import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;

public class FileUtils {
    public static final int REQUEST_CODE_VIDEO_CAPTURE = 1001;

    public static File createVideoFile(Context context) throws IOException {
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss", Locale.getDefault()).format(new Date());
        String videoFileName = "VIDEO_" + timeStamp + ".mp4";
        File storageDir = context.getExternalFilesDir(Environment.DIRECTORY_MOVIES);
        return File.createTempFile(videoFileName, ".mp4", storageDir);
    }

    public static void captureVideo(Activity activity) {
        Intent takeVideoIntent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);
        if (takeVideoIntent.resolveActivity(activity.getPackageManager()) != null) {
            File videoFile = null;
            try {
                videoFile = createVideoFile(activity);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (videoFile != null) {
                Uri videoUri;
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
                    videoUri = FileProvider.getUriForFile(activity, activity.getPackageName() + ".fileprovider", videoFile);
                } else {
                    videoUri = Uri.fromFile(videoFile);
                }
                takeVideoIntent.putExtra(MediaStore.EXTRA_OUTPUT, videoUri);
                activity.startActivityForResult(takeVideoIntent, REQUEST_CODE_VIDEO_CAPTURE);
            }
        }
    }

    public static void deleteVideoFile(Context context, Uri videoUri) {
        File videoFile = new File(videoUri.getPath());
        if (videoFile.exists()) {
            videoFile.delete();
        }
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            context.getContentResolver().delete(videoUri, null, null);
        } else {
            context.getContentResolver().delete(MediaStore.Video.Media.EXTERNAL_CONTENT_URI, MediaStore.Video.Media.DATA + "=?", new String[]{videoFile.getAbsolutePath()});
        }
    }
}

3. 在需要捕获视频的Activity中，调用FileUtils.captureVideo(this)方法以调起系统摄像机应用程序。例如：

public class MainActivity extends AppCompatActivity {
    private Uri videoUri;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button captureButton = findViewById(R.id.capture_button);
        captureButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                FileUtils.captureVideo(MainActivity.this);
            }
        });
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == FileUtils.REQUEST_CODE_VIDEO_CAPTURE && resultCode == RESULT_OK) {
            if (data != null && data.getData() != null) {
                videoUri = data.getData();
                // 处理视频文件
            }
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();

        if (videoUri != null) {
            FileUtils.deleteVideoFile(this, videoUri);
        }
    }
}

这些代码将允许您在Android设备上捕获视频，并在捕获完成后处理视频文件。请注意，这些代码将视频文件存储在应用程序的私有目录中，并在Activity销毁时删除视频文件。