Question

我很困惑为什么我不能使用OutputFormat.OUTPUT_FORMAT_MPEG2TS作为Android版本2.3.6设备上MediaRecorder.setOutputFormat方法调用的参数？

在android源代码中有这个代码位：

/**
* Defines the output format. These constants are used with
* {@link MediaRecorder#setOutputFormat(int)}.
*/
public final class OutputFormat {
    /* Do not change these values without updating their counterparts
    * in include/media/mediarecorder.h!
    */
    private OutputFormat() {}
    public static final int DEFAULT = 0;
    /** 3GPP media file format*/
    public static final int THREE_GPP = 1;
    /** MPEG4 media file format*/
    public static final int MPEG_4 = 2;

    /** The following formats are audio only .aac or .amr formats **/
    /** @deprecated  Deprecated in favor of AMR_NB */
    /** Deprecated in favor of MediaRecorder.OutputFormat.AMR_NB */
    /** AMR NB file format */
    public static final int RAW_AMR = 3;
    /** AMR NB file format */
    public static final int AMR_NB = 3;
    /** AMR WB file format */
    public static final int AMR_WB = 4;
    /** @hide AAC ADIF file format */
    public static final int AAC_ADIF = 5;
    /** @hide AAC ADTS file format */
    public static final int AAC_ADTS = 6;

    /** @hide Stream over a socket, limited to a single stream */
    public static final int OUTPUT_FORMAT_RTP_AVP = 7;

    /** @hide H.264/AAC data encapsulated in MPEG2/TS */
    public static final int OUTPUT_FORMAT_MPEG2TS = 8;
};

测试设备是三星galaxy note，显示android版本2.3.6。

MediaRecorder.setAudioSource（7）调用不会引发错误，即使它也是隐藏选项（MediaRecorder.AudioSource.VOICE_COMMUNICATION == 7）。

MediaRecorder.setOutputFormat（8）调用抛出异常whit这个日志输出：

    03-21 17:45:27.330: E/MediaRecorder(30622): setOutputFormat failed: -2147483648

以下是MediaRecorder.setOutputFormat来电时失败的代码：

import java.io.IOException;

import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.media.CamcorderProfile;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.view.WindowManager;

public class CameraStreamer extends Activity implements OnClickListener, SurfaceHolder.Callback 
{
    MediaRecorder recorder;
    SurfaceHolder holder;
    boolean recording = false;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);

        recorder = new MediaRecorder();
        initRecorder();

        setContentView(R.layout.main);
        SurfaceView cameraView = (SurfaceView) findViewById(R.id.CameraView);
        holder = cameraView.getHolder();
        holder.addCallback(this);
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

        cameraView.setClickable(true);
        cameraView.setOnClickListener(this);
    }
    private void initRecorder() {
        recorder.setAudioSource(7); //MediaRecorder.AudioSource.VOICE_COMMUNICATION); //MediaRecorder.AudioSource.MIC);
        recorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);

        recorder.setOutputFormat(8); //MediaRecorder.OutputFormat.OUTPUT_FORMAT_MPEG2TS);

        // for reference only
        CamcorderProfile cpHigh = CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH);

        int width=320, height=240;
        recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AAC);
        recorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264);
        recorder.setVideoSize(width, height);
        recorder.setVideoFrameRate(25);
        recorder.setVideoEncodingBitRate(cpHigh.videoBitRate);
        recorder.setAudioEncodingBitRate(cpHigh.audioBitRate);
        recorder.setAudioChannels(1);
        recorder.setAudioSamplingRate(cpHigh.audioSampleRate);

        // recorder.setProfile(cpHigh); // This sets format, framerate, size, bitrate, channels, sampling rate, encoders

        recorder.setOutputFile("/sdcard/videocapture_example.ts");
        recorder.setMaxDuration(50000); // 50 seconds
        recorder.setMaxFileSize(5000000); // Approximately 5 megabytes
    }
    private void prepareRecorder() {
        recorder.setPreviewDisplay(holder.getSurface());

        try {
            recorder.prepare();
        } catch (IllegalStateException e) {
            e.printStackTrace();
            finish();
        } catch (IOException e) {
            e.printStackTrace();
            finish();
        }
    }
    public void onClick(View v) {
        if (recording) {
            recorder.stop();
            recording = false;

            // Let's initRecorder so we can record again
            initRecorder();
            prepareRecorder();
        } else {
            recording = true;
            recorder.start();
        }
    }

    public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
        // TODO Auto-generated method stub

    }

    public void surfaceCreated(SurfaceHolder arg0) {
        prepareRecorder();
    }

    public void surfaceDestroyed(SurfaceHolder arg0) {
        if (recording) {
            recorder.stop();
            recording = false;
        }
        recorder.release();
        finish();
    }

}

Answer 1

实际上，这一切都取决于特定设备上的硬件和软件实现。

运行android 4.0的三星galaxy note可以在文件或套接字描述符中输出MPEG-TS流。

如何在android设备上指定OUTPUT_FORMAT_MPEG2TS

1 个答案: