MediaRecorder

public class MediaRecorder
extends Object
java.lang.Object
↳
android.media.MediaRecorder

---

用来录制audio和vedio，录制控制是基于简单的状态机制如图。

MediaRecorder state diagram

通常使用录制的代码如下

MediaRecorder recorder = new MediaRecorder();
 recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
 recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP); 
recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB); 
recorder.setOutputFile(PATH_NAME);
 recorder.prepare();
 recorder.start();   // Recording is now started ... 
//your code
recorder.stop();
 recorder.reset();   // You can reuse the object by going back to setAudioSource() 
step recorder.release(); // Now the object cannot be reused

可以设置setOnInfoListener(OnInfoListener)setOnInfoListener 或者 setOnErrorListener(OnErrorListener)
setOnErrorListener）

注意：目前，MediaRecorder不会在模拟器上工作。

开发人员指南

For more information about how to use MediaRecorder for recording video, read the Camera developer guide. For more information about how to use MediaRecorder for recording sound, read the Audio Capture developer guide.

音频捕获

Android的多媒体框架包括用于捕获和编码多种常见的音频格式，让你可以轻松的音频集成到应用程序的支持。 使用您可以录制音频MediaRecorder
的API如果设备硬件支持。
本文向您介绍如何编写从设备麦克风捕获音频的应用，保存音频回放。

注意：Android模拟器不必捕获音频的能力，但实际的设备有可能提供这些功能。

执行音频捕获 从设备音频采集是有点比音频和视频播放更复杂，但仍然相当简单：

• 创建的新实例android.media.MediaRecorder

• 设置使用音频源MediaRecorder.setAudioSource() 你可能会想使用MediaRecorder.AudioSource.MIC

• 使用设置输出文件格式MediaRecorder.setOutputFormat()

• 使用设置输出文件名MediaRecorder.setOutputFile()

• 设置使用音频编码器MediaRecorder.setAudioEncoder()

• 调用MediaRecorder.prepare()在MediaRecorder实例。

• 要启动音频采集，调用MediaRecorder.start()

• 要停止音频采集，调用MediaRecorder.stop()

• 当你与MediaRecorder实例来完成，调用MediaRecorder.release()
  就可以了。 调用MediaRecorder.release()总是建议立即释放资源。

例如：录制音频和播放录制的音频
下面的例子说明了类如何设置，启动和停止音频采集和播放录制的音频文件。

/*
 * The application needs to have the permission to write to external storage
 * if the output file is written to the external storage, and also the
 * permission to record audio. These permissions must be set in the
 * application's AndroidManifest.xml file, with something like:
 *
 * 
 * 
 *
 */
package com.android.audiorecordtest;

import android.app.Activity;
import android.widget.LinearLayout;
import android.os.Bundle;
import android.os.Environment;
import android.view.ViewGroup;
import android.widget.Button;
import android.view.View;
import android.view.View.OnClickListener;
import android.content.Context;
import android.util.Log;
import android.media.MediaRecorder;
import android.media.MediaPlayer;

import java.io.IOException;


public class AudioRecordTest extends Activity
{
    private static final String LOG_TAG = "AudioRecordTest";
    private static String mFileName = null;

    private RecordButton mRecordButton = null;
    private MediaRecorder mRecorder = null;

    private PlayButton   mPlayButton = null;
    private MediaPlayer   mPlayer = null;

    private void onRecord(boolean start) {
        if (start) {
            startRecording();
        } else {
            stopRecording();
        }
    }

    private void onPlay(boolean start) {
        if (start) {
            startPlaying();
        } else {
            stopPlaying();
        }
    }

    private void startPlaying() {
        mPlayer = new MediaPlayer();
        try {
            mPlayer.setDataSource(mFileName);
            mPlayer.prepare();
            mPlayer.start();
        } catch (IOException e) {
            Log.e(LOG_TAG, "prepare() failed");
        }
    }

    private void stopPlaying() {
        mPlayer.release();
        mPlayer = null;
    }

    private void startRecording() {
        mRecorder = new MediaRecorder();
        mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
        mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
        mRecorder.setOutputFile(mFileName);
        mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);

        try {
            mRecorder.prepare();
        } catch (IOException e) {
            Log.e(LOG_TAG, "prepare() failed");
        }

        mRecorder.start();
    }

    private void stopRecording() {
        mRecorder.stop();
        mRecorder.release();
        mRecorder = null;
    }

    class RecordButton extends Button {
        boolean mStartRecording = true;

        OnClickListener clicker = new OnClickListener() {
            public void onClick(View v) {
                onRecord(mStartRecording);
                if (mStartRecording) {
                    setText("Stop recording");
                } else {
                    setText("Start recording");
                }
                mStartRecording = !mStartRecording;
            }
        };

        public RecordButton(Context ctx) {
            super(ctx);
            setText("Start recording");
            setOnClickListener(clicker);
        }
    }

    class PlayButton extends Button {
        boolean mStartPlaying = true;

        OnClickListener clicker = new OnClickListener() {
            public void onClick(View v) {
                onPlay(mStartPlaying);
                if (mStartPlaying) {
                    setText("Stop playing");
                } else {
                    setText("Start playing");
                }
                mStartPlaying = !mStartPlaying;
            }
        };

        public PlayButton(Context ctx) {
            super(ctx);
            setText("Start playing");
            setOnClickListener(clicker);
        }
    }

    public AudioRecordTest() {
        mFileName = Environment.getExternalStorageDirectory().getAbsolutePath();
        mFileName += "/audiorecordtest.3gp";
    }

    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);

        LinearLayout ll = new LinearLayout(this);
        mRecordButton = new RecordButton(this);
        ll.addView(mRecordButton,
            new LinearLayout.LayoutParams(
                ViewGroup.LayoutParams.WRAP_CONTENT,
                ViewGroup.LayoutParams.WRAP_CONTENT,
                0));
        mPlayButton = new PlayButton(this);
        ll.addView(mPlayButton,
            new LinearLayout.LayoutParams(
                ViewGroup.LayoutParams.WRAP_CONTENT,
                ViewGroup.LayoutParams.WRAP_CONTENT,
                0));
        setContentView(ll);
    }

    @Override
    public void onPause() {
        super.onPause();
        if (mRecorder != null) {
            mRecorder.release();
            mRecorder = null;
        }

        if (mPlayer != null) {
            mPlayer.release();
            mPlayer = null;
        }
    }
}