android - MediaRecorder，录制音视频音量很低

Question

我在 android 项目上使用 MediaRecorder 来录制视频和音频文件。它可以正确录制，但两个文件的音量都非常低。

我用它来配置 MediaRecorder 来录制音频

String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
                    File folder = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + ConfigApp.RECORDINGS_FOLDER);
                    if (!folder.exists())
                        success = folder.mkdir();
                    if (success) {
                        mFileName = folder + timeStamp + ".m4a";
                        currentFile = mFileName;
                        chrono.setBase(SystemClock.elapsedRealtime());
                        chrono.start();
                        mRecorder = new MediaRecorder();
                        mRecorder.setAudioSource(MediaRecorder.AudioSource.CAMCORDER);
                        mRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
                        mRecorder.setOutputFile(mFileName);
                        mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);


                        try {
                            mRecorder.prepare();
                        } catch (IOException e) {
                            Log.e(TAG, "prepare() failed");
                        }
                        mRecorder.start();
                        handler.post(updateVisualizer);
                    }

当我录制视频时这是

// BEGIN_INCLUDE (configure_preview)
    mCamera = CameraHelper.getDefaultCameraInstance();
    // We need to make sure that our preview and recording video size are supported by the
    // camera. Query camera to find all the sizes and choose the optimal size given the
    // dimensions of our preview surface.
    Camera.Parameters parameters = mCamera.getParameters();
    List<Camera.Size> mSupportedPreviewSizes = parameters.getSupportedPreviewSizes();
    Camera.Size optimalSize = CameraHelper.getOptimalPreviewSize(mSupportedPreviewSizes,
            mSurfaceView.getWidth(), mSurfaceView.getHeight());

    // Use the same size for recording profile.
    CamcorderProfile profile = CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH);
    profile.videoFrameWidth = optimalSize.width;
    profile.videoFrameHeight = optimalSize.height;

    // likewise for the camera object itself.
    parameters.setPreviewSize(profile.videoFrameWidth, profile.videoFrameHeight);
    mCamera.setParameters(parameters);
    try {
        // Requires API level 11+, For backward compatibility use {@link setPreviewDisplay}
        // with {@link SurfaceView}
        mCamera.setPreviewDisplay(mSurfaceView.getHolder());
        mCamera.setDisplayOrientation(90);

    } catch (IOException e) {
        Log.e(TAG, "Surface texture is unavailable or unsuitable" + e.getMessage());
        return false;
    }
    // END_INCLUDE (configure_preview)


    // BEGIN_INCLUDE (configure_media_recorder)
    mMediaRecorder = new MediaRecorder();

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

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

    // Step 3: Set a CamcorderProfile (requires API Level 8 or higher)
    mMediaRecorder.setProfile(profile);

    // Step 4: Set output file
    String path  = getVideoFile(MediaStore.Files.FileColumns.MEDIA_TYPE_VIDEO).getAbsolutePath();
    currentFile = path;
    mMediaRecorder.setOutputFile(path);
    mMediaRecorder.setOrientationHint(270);

    // END_INCLUDE (configure_media_recorder)

    // Step 5: Prepare configured MediaRecorder
    try {
        mMediaRecorder.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;

除了 AudioSource.CAMCORDER 之外，我还在 setAudioSource 上尝试了其他选项，但音量总是很低

我需要配置任何额外的参数吗？

Answer 1

我在使用 MediaRecorder 时遇到了同样的问题，最终找到了正确的工作解决方案。以下是您需要为高质量录音做的一些修改:
mRecorder.setAudioEncodingBitRate(16*44100);
mRecorder.setAudioSamplingRate(44100);
stackoverflow 上的许多解决方案建议使用 .setAudioEncodingBiteRate(16)，但 16 太低而不能被视为无意义。

来源:@Grant 在 stackoverflow 上的回答 very poor quality of audio recorded on my droidx using MediaRecorder, why?