Question

我试图将使用android mediarecorder的音频记录拆分为多个文件，但是每当设置下一个输出文件时，我都会收到一个非法状态异常。

代码如下：

    private void getMediaRecorderReady(String filePath, FileDescriptor nextFile) {
    bufferSize = 88200;
    recorder = new MediaRecorder();
    recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
    recorder.setOutputFormat(MediaRecorder.OutputFormat.AAC_ADTS);
    recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AAC);
    recorder.setAudioEncodingBitRate(64000);
    recorder.setAudioSamplingRate(44100);
    recorder.setAudioChannels(1);
    recorder.setOutputFile(filePath);
    recorder.setMaxDuration(1000);
    recorder.setMaxFileSize(100000);
    try {
        recorder.prepare();
        recorder.setNextOutputFile(nextFile);
    } catch (IOException e) {
        e.printStackTrace();
    }
}

这是错误：

E/MediaRecorder: setNextOutputFile failed: -38
E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #1
              Process: com.example.a49164.teachmi, PID: 31554
              java.lang.RuntimeException: An error occurred while executing doInBackground()
                  at android.os.AsyncTask$3.done(AsyncTask.java:353)
                  at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:383)
                  at java.util.concurrent.FutureTask.setException(FutureTask.java:252)
                  at java.util.concurrent.FutureTask.run(FutureTask.java:271)
                  at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:245)
                  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)
                  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)
                  at java.lang.Thread.run(Thread.java:764)
               Caused by: java.lang.IllegalStateException
                  at android.media.MediaRecorder._setNextOutputFile(Native Method)
                  at android.media.MediaRecorder.setNextOutputFile(MediaRecorder.java:878)
                  at com.example.a49164.teachmi.ExComThread.getMediaRecorderReady(ExComThread.java:189)
                  at com.example.a49164.teachmi.ExComThread.soundTransfer(ExComThread.java:211)
                  at com.example.a49164.teachmi.ExComThread.doInBackground(ExComThread.java:82)
                  at com.example.a49164.teachmi.ExComThread.doInBackground(ExComThread.java:46)
                  at android.os.AsyncTask$2.call(AsyncTask.java:333)
                  at java.util.concurrent.FutureTask.run(FutureTask.java:266)
                  at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:245) 
                  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162) 
                  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636) 
                  at java.lang.Thread.run(Thread.java:764)

因此，在进行一些挖掘之后，错误-38等于“ -ENOSYS”或“ INVALID_OPERATION”，如果记录器为null或未调用prepare似乎会发生（但我确实先调用prepare（））。

这是一些本地android代码：

enum {
OK                = 0,    // Everything's swell.
NO_ERROR          = 0,    // No errors.

UNKNOWN_ERROR       = 0x80000000,
NO_MEMORY           = -ENOMEM,
INVALID_OPERATION   = -ENOSYS,
BAD_VALUE           = -EINVAL,
BAD_TYPE            = 0x80000001,
NAME_NOT_FOUND      = -ENOENT,
PERMISSION_DENIED   = -EPERM,
NO_INIT             = -ENODEV,
ALREADY_EXISTS      = -EEXIST,
DEAD_OBJECT         = -EPIPE,
FAILED_TRANSACTION  = 0x80000002,
JPARKS_BROKE_IT     = -EPIPE,
#if !defined(HAVE_MS_C_RUNTIME)
BAD_INDEX           = -EOVERFLOW,
NOT_ENOUGH_DATA     = -ENODATA,
WOULD_BLOCK         = -EWOULDBLOCK, 
TIMED_OUT           = -ETIMEDOUT,
UNKNOWN_TRANSACTION = -EBADMSG,
#else    
BAD_INDEX           = -E2BIG,
NOT_ENOUGH_DATA     = 0x80000003,
WOULD_BLOCK         = 0x80000004,
TIMED_OUT           = 0x80000005,
UNKNOWN_TRANSACTION = 0x80000006,
#endif    
FDS_NOT_ALLOWED     = 0x80000007,
};

native nextoutputfile：

status_t MediaRecorder::setNextOutputFile(int fd)
{
ALOGV("setNextOutputFile(%d)", fd);
if (mMediaRecorder == NULL) {
    ALOGE("media recorder is not initialized yet");
    return INVALID_OPERATION;
}
// It appears that if an invalid file descriptor is passed through
// binder calls, the server-side of the inter-process function call
// is skipped. As a result, the check at the server-side to catch
// the invalid file descritpor never gets invoked. This is to workaround
// this issue by checking the file descriptor first before passing
// it through binder call.
int flags = fcntl(fd, F_GETFL);
if (flags == -1) {
    ALOGE("Fail to get File Status Flags err: %s", strerror(errno));
}
// fd must be in read-write mode or write-only mode.
if ((flags & (O_RDWR | O_WRONLY)) == 0) {
    ALOGE("File descriptor is not in read-write mode or write-only mode");
    return BAD_VALUE;
}
status_t ret = mMediaRecorder->setNextOutputFile(fd);
if (OK != ret) {
    ALOGE("setNextOutputFile failed: %d", ret);
}
return ret;
}

关于-38等于-ENOSYS的事实，我可能是错的，但是我仍然不知道为什么它不起作用，因为我要传递文件描述符，并在准备后调用它，如android文档中所述

我非常欢迎您的帮助，谢谢！

编辑：我试图在准备好之后立即删除setNextOutputFile（nextFile），只保留其中一个：

    recorder.setOnInfoListener(new MediaRecorder.OnInfoListener() {
        @Override
        public void onInfo(MediaRecorder mr, int infoCode, int extra) {
            System.out.println("----------------------------------------onMaxFileSizeApproaching " + infoCode);
            if (infoCode == MediaRecorder.MEDIA_RECORDER_INFO_MAX_FILESIZE_REACHED) {
                System.out.println("max sized reached");
                String path = Environment.getExternalStorageDirectory().getPath() + "/dataSound" + currFile + ".aac";
                File nextFile = new File(path);
                try {
                    FileOutputStream fos = new FileOutputStream(nextFile);
                    recorder.setNextOutputFile(fos.getFD());
                } catch (IOException e) {
                    e.printStackTrace();
                }
                String currPath = Environment.getExternalStorageDirectory().getPath() + "/dataSound" + (currFile - 1) + ".aac";
                sendDataPath = currPath;
                currFile++;
            }
        }
    });

但无济于事...

Answer 1

这意味着!bash -c 'mv cat.{0..499}.jpg /content/train'在setNextOutputFile() finish it's own work之前被调用。

因此，您应该等到documentation中讨论的文件准备完毕。

在切换到该输出之前，不使用该文件。申请将收到MEDIA_RECORDER_INFO_NEXT_OUTPUT_FILE_STARTED

您应该听以下文件信息：

prepare()

也使用下一个输出文件时。如果未使用前一个输出文件，则应用程序将无法设置新的输出文件。应用程序负责在调用recorder.setOnInfoListener(new MediaRecorder.OnInfoListener() { @Override public void onInfo(MediaRecorder mediaRecorder, int what, int extra) { if (what == MediaRecorder.MEDIA_RECORDER_INFO_MAX_FILESIZE_REACHED) recorder.setNextOutputFile(nextFile); } });之后清理未使用的文件。

Answer 2

根据文档，setNextOutputFile API必须在MediaRecorder.OnInfoListener上收到MEDIA_RECORDER_INFO_MAX_FILESIZE_APPROACHING的“内容”代码后立即调用

mediaRecorder.setOnInfoListener(new MediaRecorder.OnInfoListener() {
    @Override
    public void onInfo(MediaRecorder mr, int what, int extra) {
        Toast.makeText(RecordActivity.this, "MediaRecorder onInfo:"+what, Toast.LENGTH_LONG).show();
        Log.w("RecordActivity","MediaRecorder onInfo:"+what);
        if (what == MEDIA_RECORDER_INFO_MAX_FILESIZE_APPROACHING) {

            File mediaStorageDir = new File(Environment.getExternalStorageDirectory(), "MyRecordings");
            if (!mediaStorageDir.exists()){
                mediaStorageDir.mkdirs();
            }
            Date date= new java.util.Date();
            String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss")
                    .format(date.getTime());
            String mediaFilePath = mediaStorageDir.getPath() + File.separator +
                    "VID_"+ timeStamp + ".mp4";
            File mediaFile = new File(mediaFilePath);

            Log.e("RecordActivity",mediaFilePath);
            try {
                RandomAccessFile f = new RandomAccessFile(mediaFile, "rw");
                try {
                    mediaRecorder.setNextOutputFile(f.getFD());

                } finally {
                    f.close();
                }
            } catch(Exception ex) {
                Log.e("RecordActivity","",ex);
            }
        }
    }

});

Android Mediarecorder setNextOutputFile IllegalStateException

2 个答案: