Question

我正在尝试添加手动相机控制新的曝光值和ISO值。我正在使用Camera2Basic示例。我现在面临的问题是我是Android新手。我试着看着L-Camera，但它在Scala中让我更加困惑。

我尝试了以下更改，但没有更新图像的预览。

 private void createCameraPreviewSession() {
    try {
        SurfaceTexture texture = mTextureView.getSurfaceTexture();
        assert texture != null;

        // We configure the size of default buffer to be the size of camera preview we want.
        texture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight());

        // This is the output Surface we need to start preview.
        Surface surface = new Surface(texture);

        // We set up a CaptureRequest.Builder with the output Surface.
        mPreviewRequestBuilder
                = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
        mPreviewRequestBuilder.addTarget(surface);

        // Here, we create a CameraCaptureSession for camera preview.
        mCameraDevice.createCaptureSession(Arrays.asList(surface, mImageReader.getSurface()),
                new CameraCaptureSession.StateCallback() {

                    @Override
                    public void onConfigured(@NonNull CameraCaptureSession cameraCaptureSession) {
                        // The camera is already closed
                        if (null == mCameraDevice) {
                            return;
                        }

                        // When the session is ready, we start displaying the preview.
                        mCaptureSession = cameraCaptureSession;
                        try {
                            // Auto focus should be continuous for camera preview.
                            mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE,
                                    CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);

                            mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE,
                                    CaptureRequest.CONTROL_AE_MODE_OFF);

                            mPreviewRequestBuilder.set(CaptureRequest.SENSOR_EXPOSURE_TIME,Long.valueOf("100000"));
                            mPreviewRequestBuilder.set(CaptureRequest.SENSOR_SENSITIVITY,1600);

                            // Flash is automatically enabled when necessary.
                            setAutoFlash(mPreviewRequestBuilder);

                            // Finally, we start displaying the camera preview.
                            mPreviewRequest = mPreviewRequestBuilder.build();
                            mCaptureSession.setRepeatingRequest(mPreviewRequest,
                                    mCaptureCallback, mBackgroundHandler);
                        } catch (CameraAccessException e) {
                            e.printStackTrace();
                        }
                    }

                    @Override
                    public void onConfigureFailed(
                            @NonNull CameraCaptureSession cameraCaptureSession) {
                        showToast("Failed");
                    }
                }, null
        );
    } catch (CameraAccessException e) {
        e.printStackTrace();
    }
}

Answer 1

首先，您必须将模板更改为TEMPLATE_STILL_CAPTURE或TEMPLATE_MANUAL，才能在预览中看到值的变化。另外，请记住将CONTROL_AE_MODE和'CONTROL_MODE'设置为OFF。

此控件仅在android.control.aeMode或android.control.mode设置为OFF时有效;否则自动曝光算法将覆盖此值。

来自Android Developer

其次，设置您的值：

builder.set(CaptureRequest.SENSOR_SENSITIVITY, isoValue);
builder.set(CaptureRequest.SENSOR_EXPOSURE_TIME, exposureTimeValueInMilliseconds);

最后，在完成所有更改后，请不要忘记使用CaptureSession.setRepeatingRequest

更新预览

希望它会对你有所帮助！

Answer 2

所以我对我的代码进行了以下更改。

mPreviewRequestBuilder
    = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_MANUAL);
mPreviewRequestBuilder.addTarget(surface);


mPreviewRequestBuilder.set(CaptureRequest.CONTROL_MODE,
    CaptureRequest.CONTROL_MODE_OFF);

mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE,
    CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);

mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE,
    CaptureRequest.CONTROL_AE_MODE_OFF);

mPreviewRequestBuilder.set(CaptureRequest.SENSOR_EXPOSURE_TIME,Long.valueOf("22000"));
mPreviewRequestBuilder.set(CaptureRequest.SENSOR_SENSITIVITY,200);

mCaptureSession.setRepeatingRequest(mPreviewRequest,
    mCaptureCallback, mBackgroundHandler);

然而，我得到了一个奇怪的预览，其中有许多绿灯作为输入。

这是https://postimg.org/image/yl95e6qht/

这就像使用我内置的相机应用程序一样：https://postimg.org/image/lvjnwquj5/

Answer 3

这将解决问题：

mPreviewBuilder.set(
    CaptureRequest.CONTROL_AWB_MODE, 
    CaptureRequest.CONTROL_AWB_MODE_AUTO
);

Answer 4

在使用Camera 2 API进行手动曝光时，我也遇到绿色拍摄问题。我可以通过仅停用CONTROL_AE_MODE而不是同时CONTROL_AE_MODE和CONTROL_MODE来解决此问题。这是我的配置：

final CaptureRequest.Builder captureBuilder = cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);

captureBuilder.set(CaptureRequest.CONTROL_AE_MODE, CameraCharacteristics.CONTROL_AE_MODE_OFF);
captureBuilder.set(CaptureRequest.CONTROL_MODE, CameraCharacteristics.CONTROL_MODE_AUTO);
captureBuilder.set(CaptureRequest.SENSOR_EXPOSURE_TIME, Long.valueOf("8000000")); // 8000000 ns = 8 ms

在android camera2API中控制传感器ISO和曝光时间

4 个答案: