要在Android上播放URL图像的增强现实（AR）视频，可以使用Google的ARCore库结合Google ExoPlayer库。下面是一个简单的代码示例：

1. 首先，确保在项目的build.gradle文件中添加以下依赖项：

dependencies {
    // ARCore库
    implementation 'com.google.ar:core:1.26.0'
    
    // ExoPlayer库
    implementation 'com.google.android.exoplayer:exoplayer:2.15.0'
}

2. 在你的Activity类中，实现ARCore的ArFragment.OnViewCreatedListener接口，并在onViewCreated()方法中初始化ExoPlayer。这里假设你已经有一个用于显示AR内容的ArFragment：

import android.net.Uri;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import androidx.annotation.NonNull;
import androidx.fragment.app.Fragment;

import com.google.ar.core.ArCoreApk;
import com.google.ar.sceneform.AnchorNode;
import com.google.ar.sceneform.FrameTime;
import com.google.ar.sceneform.rendering.ModelRenderable;
import com.google.ar.sceneform.ux.ArFragment;
import com.google.ar.sceneform.ux.TransformableNode;
import com.google.android.exoplayer2.ExoPlayer;
import com.google.android.exoplayer2.SimpleExoPlayer;
import com.google.android.exoplayer2.source.MediaSource;
import com.google.android.exoplayer2.source.ProgressiveMediaSource;
import com.google.android.exoplayer2.ui.PlayerView;
import com.google.android.exoplayer2.upstream.DefaultDataSourceFactory;
import com.google.android.exoplayer2.util.Util;

public class ARVideoFragment extends Fragment implements ArFragment.OnViewCreatedListener {
    private ArFragment arFragment;
    private SimpleExoPlayer player;
    private PlayerView playerView;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_ar_video, container, false);
        playerView = rootView.findViewById(R.id.player_view);
        return rootView;
    }

    @Override
    public void onViewCreated(@NonNull View view, @NonNull Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        arFragment = (ArFragment) getChildFragmentManager().findFragmentById(R.id.ar_fragment);
        arFragment.setOnViewCreatedListener(this);
    }

    @Override
    public void onViewCreated(ArFragment arFragment, ArSceneView arSceneView) {
        // 加载AR内容
        loadARContent(arSceneView);

        // 初始化并播放视频
        initializePlayer();
        playVideo();
    }

    @Override
    public void onPause() {
        super.onPause();
        if (player != null) {
            player.setPlayWhenReady(false);
        }
    }

    @Override
    public void onResume() {
        super.onResume();
        if (player != null) {
            player.setPlayWhenReady(true);
        }
    }

    private void loadARContent(ArSceneView arSceneView) {
        // 加载AR模型等内容
        // ...
    }

    private void initializePlayer() {
        // 创建ExoPlayer实例
        player = new SimpleExoPlayer.Builder(getContext()).build();
        playerView.setPlayer(player);
    }

    private void playVideo() {
        // 视频URL
        String videoUrl = "YOUR_VIDEO_URL";

        // 创建数据源工厂
        DefaultDataSourceFactory dataSourceFactory = new DefaultDataSourceFactory(getContext(), Util.getUserAgent(getContext(), getString(R.string.app_name)));

        // 创建媒体源
        MediaSource videoSource = new ProgressiveMediaSource.Factory(dataSourceFactory).createMediaSource(Uri.parse(videoUrl));

        // 准备播放器
        player.prepare(videoSource);
        player.setPlayWhenReady(true);
    }
}

3. 在布局文件fragment_ar_video.xml中，添加一个ArFragment和一个PlayerView用于显示视频：

请确保将YOUR_VIDEO_URL替换为实际的视频