如何在 android 设备中录制内部音频 [root/no root]

Posted 2023-02-25

【中文标题】如何在 android 设备中录制内部音频 [root/no root]

【英文标题】：How to record internal audio [root/no root] in android devices

【发布时间】：2020-01-27 07:44:43

【问题描述】：

我在录制屏幕表面时使用并尝试过 MediaRecorder.Audiosource.REMOTE_SUBMIX，由于权限问题，应用程序崩溃，在 HTC 10 中测试[根植于 superSu 中]。

虽然它适用于以下输入：

mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.DEFAULT);

我想在不使用麦克风的情况下录制系统的内部/输出音频。 要求： 我需要记录屏幕的活动以及音频（不使用麦克风）， 当屏幕录像机打开时，如果播放 youtube，我需要记录它的音频以及屏幕活动（不使用麦克风）。我只面临音频部分的挑战，请建议

private void initRecorder() 
        try 
            mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.REMOTE_SUBMIX);
            mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.SURFACE);
            mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
            mMediaRecorder.setOutputFile(Environment
                    .getExternalStoragePublicDirectory(Environment
                            .DIRECTORY_DOWNLOADS) + "/video.mp4");
            mMediaRecorder.setVideoSize(DISPLAY_WIDTH, DISPLAY_HEIGHT);
            mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264);
            mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
            mMediaRecorder.setVideoEncodingBitRate(512 * 1000);
            mMediaRecorder.setVideoFrameRate(30);
            int rotation = getWindowManager().getDefaultDisplay().getRotation();
            int orientation = ORIENTATIONS.get(rotation + 90);
            mMediaRecorder.setOrientationHint(orientation);
            mMediaRecorder.prepare();
         catch (IOException e) 
            e.printStackTrace();
        
    

开始录制会弹出一个权限对话框，同时创建以下Logcat条目

2020-01-27 12:38:19.463 3958-3958/com.truiton.screencapture E/MediaRecorder: prepare failed: -2147483648

单击立即开始（用户权限）会使应用程序崩溃并显示以下 logcat 输出

2020-01-27 12:55:09.174 12787-12787/com.truiton.screencapture E/MediaRecorder: start called in an invalid state: 0
2020-01-27 12:55:09.178 12787-12787/com.truiton.screencapture E/MediaRecorder: Failed to start recording
java.lang.IllegalStateException
at android.media.MediaRecorder._start(Native Method)
at android.media.MediaRecorder.start(MediaRecorder.java:1063)
at com.truiton.screencapture.MainActivity.onActivityResult(MainActivity.java:122)
at android.app.Activity.dispatchActivityResult(Activity.java:7246)
at android.app.ActivityThread.deliverResults(ActivityThread.java:4577)
at android.app.ActivityThread.handleSendResult(ActivityThread.java:4631)
at android.app.ActivityThread.-wrap19(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1699)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:180)
at android.app.ActivityThread.main(ActivityThread.java:6944)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:835)
2020-01-27 12:55:09.183 12787-12787/com.truiton.screencapture E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.truiton.screencapture, PID: 12787
java.lang.RuntimeException: Failure delivering result ResultInfowho=null, request=1000, result=-1, data=Intent  (has extras)  to activity com.truiton.screencapture/com.truiton.screencapture.MainActivity: java.lang.IllegalStateException
at android.app.ActivityThread.deliverResults(ActivityThread.java:4581)
at android.app.ActivityThread.handleSendResult(ActivityThread.java:4631)
at android.app.ActivityThread.-wrap19(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1699)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:180)
at android.app.ActivityThread.main(ActivityThread.java:6944)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:835)
Caused by: java.lang.IllegalStateException
at android.media.MediaRecorder._start(Native Method)
at android.media.MediaRecorder.start(MediaRecorder.java:1063)
at com.truiton.screencapture.MainActivity.onActivityResult(MainActivity.java:122)
at android.app.Activity.dispatchActivityResult(Activity.java:7246)
at android.app.ActivityThread.deliverResults(ActivityThread.java:4577)
at android.app.ActivityThread.handleSendResult(ActivityThread.java:4631) 
at android.app.ActivityThread.-wrap19(Unknown Source:0) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1699) 
at android.os.Handler.dispatchMessage(Handler.java:105) 
at android.os.Looper.loop(Looper.java:180) 
at android.app.ActivityThread.main(ActivityThread.java:6944) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:835) 

【参考方案1】：

是否添加权限： android.Manifest.permission.CAPTURE_AUDIO_