自动曝光不适用于Android Camera API v1

Question

我试图将相机功能作为我应用程序的一部分，而且我一直坚持使用相机预览步骤。

我想了解为什么如果没有明亮的光线，预览图像会保持黑暗。 这是我在开始预览之前设置的params：

mParameters = mCamera.getParameters();
List<Camera.Size> mSupportedPreviewSizes = mParameters.getSupportedPreviewSizes();
Camera.Size optimalSize = CameraHelper.getOptimalPreviewSize(mSupportedPreviewSizes, DEFAULT_PREVIEW_WIDTH, DEFAULT_PREVIEW_HEIGHT);

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

// likewise for the camera object itself.
mParameters.setPreviewSize(mProfile.videoFrameWidth, mProfile.videoFrameHeight);

// Set correct video width and height according to screen rotation
transformMatrixHelper.setVideoDimensions(optimalSize.width, optimalSize.height);
if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) {
    transformMatrixHelper.setVideoDimensions(optimalSize.height, optimalSize.width);
}
transformMatrixHelper.clearInitTextureDimension();

mParameters.setPreviewFpsRange(MAX_FPS, MAX_FPS);
mParameters.setWhiteBalance(Camera.Parameters.WHITE_BALANCE_AUTO);

// Auto-focus
if (mParameters.getSupportedFocusModes().contains(Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO)) {
    mParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO);
}

// Auto-exposure
if (mParameters.isAutoExposureLockSupported()) {
    mParameters.setAutoExposureLock(false);
}

mCamera.setParameters(mParameters);

预览后，我没有调用任何camera.autoFocus(callback)方法。 如果有人帮助我，我将非常感激，谢谢。