Question

我正在尝试在Android Studio上制作视频流应用。我想启动摄像机并将数据发送到笔记本电脑上的我自己的服务器。但是首先，我试图开始录制视频。

我从这里https://developer.android.com/guide/topics/media/camera#java开始遵循了该教程，但遇到了一些问题。

我为mediaRecorder设置了摄像机，音频和视频源，文件格式，配置文件，输出文件。然后，当我尝试设置预览显示（mediaRecorder.setPreviewDisplay( mPreview.getHolder().getSurface());）时，出现以下错误：

“ E / MediaRecorderJNI：应用程序丢失了表面”

然后，当我尝试使用mediaRecorder.prepare()时，它将崩溃：

“无效的预览图”

mPreview变量被声明为mPreview = new CameraPreview(this, mCamera);（其中CameraPreview是上面链接中显示的类）。

您有什么建议，如何预防？谢谢！

private boolean prepareVideoRecorder() {

    mCamera = getCameraInstance(whichCamera);
    mPreview = new CameraPreview(this, mCamera);
    FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
    preview.addView(mPreview);

    mediaRecorder = new MediaRecorder();

    // Step 1: Unlock and set camera to MediaRecorder
    mCamera.unlock();
    mediaRecorder.setCamera(mCamera);

    // Step 2: Set sources
    mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
    mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);

    // Customise your profile based on a pre-existing profile
    CamcorderProfile profile = CamcorderProfile.get(Camera.CameraInfo.CAMERA_FACING_FRONT,CamcorderProfile.QUALITY_LOW);
    profile.fileFormat = MediaRecorder.OutputFormat.MPEG_4;
    profile.videoCodec = MediaRecorder.VideoEncoder.MPEG_4_SP;
    profile.videoFrameHeight = 240;
    profile.videoFrameWidth = 320;
    profile.videoBitRate = 15;

    // Apply to MediaRecorder
    mediaRecorder.setProfile(profile);

    // Step 3: Set a CamcorderProfile (requires API Level 8 or higher)
    // Step 4: Set output file      
        mediaRecorder.setOutputFile(getOutputMediaFile(MEDIA_TYPE_VIDEO).toString());

    // Step 5: Set the preview output
    **// 1: HERE I set the previewDisplay.**
    mediaRecorder.setPreviewDisplay(mPreview.getHolder().getSurface());

    // Step 6: Prepare configured MediaRecorder
    try {
        **// 2: HERE will crash with "invalid surface preview"**
        mediaRecorder.prepare();
    } catch (IllegalStateException e) {
        Log.d(TAG, "IllegalStateException preparing MediaRecorder: " + e.getMessage());
        releaseMediaRecorder();
        return false;
    } catch (IOException e) {
        Log.d(TAG, "IOException preparing MediaRecorder: " + e.getMessage());
        releaseMediaRecorder();
        return false;
    }
    return true;
}

mediaRecorder.setPreviewDisplay出现问题-无效的表面

0 个答案: