是Android 2.2的HTTP渐进式流= HTTP实时流？ [英] Is Android 2.2 HTTP progressive streaming = HTTP Live Streaming?

问题描述

该Stagefrigh媒体框架（安卓2.2），支持HTTP渐进式流。
那是什么意思？即这是一个HTTP实时流协议的实现？

The Stagefrigh media framework (Android 2.2) supports HTTP progressive streaming.
What's that means? I.e. is this an HTTP Live Streaming protocol realization?

和如何使用HTTP实时流媒体在Android上，我的意思是什么客户端 - 网页浏览器，MediaPlayer的或只是在-SDK的实现，我不得不从一些类继承？

And how to use HTTP Live Streaming on Android, I mean what's the client - web browser, MediaPlayer or just "in-SDK" realization and I have to inherit from some class?

推荐答案

一大实用diffrence是Stagefright媒体框架支持MPEG3流，这是旧引擎没有。所以，你可以使用（Shoutcast一样）mp3streams为例。

One big practical diffrence is that Stagefright media Framework supports mpeg3 streaming, which the old engine didn't. So you can use (shoutcast) mp3streams for example.

下面是执行一个简单的例子，其中一个流Shoutcast的URL： http://fr3.ah.fm:9000 。请注意，这只能在Android 2.2及更高版本。

Here is a simple example of implementation, which streams a shoutcast URL: http://fr3.ah.fm:9000. Note that this only works on Android 2.2 and up.

import android.app.Activity;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;

public class SimpleMusicStream extends Activity implements
  MediaPlayer.OnCompletionListener, MediaPlayer.OnPreparedListener,
  MediaPlayer.OnErrorListener, MediaPlayer.OnBufferingUpdateListener {

 private String TAG = getClass().getSimpleName();
 private MediaPlayer mp = null;

 private Button play;
 private Button pause;
 private Button stop;

 @Override
 public void onCreate(Bundle icicle) {
  super.onCreate(icicle);
  setContentView(R.layout.main);

  play = (Button) findViewById(R.id.play);
  pause = (Button) findViewById(R.id.pause);
  stop = (Button) findViewById(R.id.stop);

  play.setOnClickListener(new View.OnClickListener() {
   public void onClick(View view) {
    play();
   }
  });

  pause.setOnClickListener(new View.OnClickListener() {
   public void onClick(View view) {
    pause();
   }
  });

  stop.setOnClickListener(new View.OnClickListener() {
   public void onClick(View view) {
    stop();
   }
  });
 }

 private void play() {
  Uri myUri = Uri.parse("http://fr3.ah.fm:9000/");
  try {
   if (mp == null) {
    this.mp = new MediaPlayer();
   } else {
    mp.stop();
    mp.reset();
   }
   mp.setDataSource(this, myUri); // Go to Initialized state
   mp.setAudioStreamType(AudioManager.STREAM_MUSIC);
   mp.setOnPreparedListener(this);
   mp.setOnBufferingUpdateListener(this);

   mp.setOnErrorListener(this);
   mp.prepareAsync();

   Log.d(TAG, "LoadClip Done");
  } catch (Throwable t) {
   Log.d(TAG, t.toString());
  }
 }

 @Override
 public void onPrepared(MediaPlayer mp) {
  Log.d(TAG, "Stream is prepared");
  mp.start();
 }

 private void pause() {
  mp.pause();
 }

 private void stop() {
  mp.stop();

 }

 @Override
 public void onDestroy() {
  super.onDestroy();
  stop();

 }

 public void onCompletion(MediaPlayer mp) {
  stop();
 }

 public boolean onError(MediaPlayer mp, int what, int extra) {
  StringBuilder sb = new StringBuilder();
  sb.append("Media Player Error: ");
  switch (what) {
  case MediaPlayer.MEDIA_ERROR_NOT_VALID_FOR_PROGRESSIVE_PLAYBACK:
   sb.append("Not Valid for Progressive Playback");
   break;
  case MediaPlayer.MEDIA_ERROR_SERVER_DIED:
   sb.append("Server Died");
   break;
  case MediaPlayer.MEDIA_ERROR_UNKNOWN:
   sb.append("Unknown");
   break;
  default:
   sb.append(" Non standard (");
   sb.append(what);
   sb.append(")");
  }
  sb.append(" (" + what + ") ");
  sb.append(extra);
  Log.e(TAG, sb.toString());
  return true;
 }

 public void onBufferingUpdate(MediaPlayer mp, int percent) {
  Log.d(TAG, "PlayerService onBufferingUpdate : " + percent + "%");
 }

    }

main.xml中：

main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
 xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="fill_parent"
 android:layout_height="fill_parent">
 <Button
  android:text="Play"
  android:id="@+id/play"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"></Button>
 <Button
  android:text="Pause"
  android:id="@+id/pause"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"></Button>
 <Button
  android:text="Stop"
  android:id="@+id/stop"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"></Button>
</LinearLayout>

了解更多 <一href="http://developer.android.com/guide/topics/media/index.html">http://developer.android.com/guide/topics/media/index.html检查异步preparation

Read more http://developer.android.com/guide/topics/media/index.html check Asynchronous Preparation

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