Error de aserción (scn == 3 || scn == 4) en void cv :: cvtColor (cv :: InputArray Android

Estoy tratando de convertir un Mat a un valor de escala de grises para que pueda obtener el valor numérico de un píxel. Estoy recibiendo una "Aserción fallida (scn == 3 || scn == 4) en void cv :: cvtColor (cv :: InputArray error" en android. Sé que me perdí algo pero no sé lo que es .

código

• Rotar la imagen desde los datos del sensor de orientación
• Imprimir contenido de matriz opencv en Java
• Ejemplo de OpenCV Template Matching en Android
• JavaCV - Rendimiento a una superficie GL
• Cómo detectar los límites de una página de pasaporte con OpenCV?

import android.nfc.Tag; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.util.Log; import android.view.Menu; import android.view.MenuItem; import android.view.SurfaceView; import android.hardware.camera2.CameraCaptureSession; import org.opencv.android.BaseLoaderCallback; import org.opencv.android.CameraBridgeViewBase; import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener2; import org.opencv.android.JavaCameraView; import org.opencv.android.LoaderCallbackInterface; import org.opencv.android.OpenCVLoader; import org.opencv.core.CvType; import org.opencv.core.Mat; import org.opencv.core.MatOfKeyPoint; import org.opencv.core.MatOfPoint; import org.opencv.imgproc.Imgproc; import org.opencv.highgui.Highgui; public class testActivity extends AppCompatActivity implements CvCameraViewListener2 { private BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this) { @Override public void onManagerConnected(int status){ switch (status){ case LoaderCallbackInterface.SUCCESS: { mOpenCvCameraView.enableView(); break; } default: { super.onManagerConnected(status); } } } }; private JavaCameraView mOpenCvCameraView; Mat bgrPixel; Mat grayPixel; Mat rgbMat; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_test); mOpenCvCameraView = (JavaCameraView) findViewById(R.id.testVideoView); mOpenCvCameraView.setMaxFrameSize(240,320); mOpenCvCameraView.setVisibility(SurfaceView.VISIBLE); mOpenCvCameraView.setCvCameraViewListener(this); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. //getMenuInflater().inflate(R.menu.menu_main, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle action bar item clicks here. The action bar will // automatically handle clicks on the Home/Up button, so long // as you specify a parent activity in AndroidManifest.xml. int id = item.getItemId(); getSupportActionBar().hide(); //noinspection SimplifiableIfStatement if (id == R.id.action_settings) { return true; } return super.onOptionsItemSelected(item); } public void onDestroy() { super.onDestroy(); if (mOpenCvCameraView != null) mOpenCvCameraView.disableView(); } public void onResume() { super.onResume(); if (!OpenCVLoader.initDebug()) { OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_9, this, mLoaderCallback); } else { mLoaderCallback.onManagerConnected(LoaderCallbackInterface.SUCCESS); } } @Override public void onPause() { super.onPause(); if (mOpenCvCameraView != null) mOpenCvCameraView.disableView(); } @Override public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) { if(rgbMat == null){ rgbMat = inputFrame.rgba(); bgrPixel= rgbMat.submat(1,1,2,2).clone(); grayPixel = new Mat(); Imgproc.cvtColor(bgrPixel, grayPixel, Imgproc.COLOR_BGR2GRAY,1); } rgbMat= inputFrame.rgba(); return rgbMat; } @Override public void onCameraViewStarted(int width, int height) { } @Override public void onCameraViewStopped() { bgrPixel.release(); grayPixel.release(); rgbMat.release(); } } 

Gato de registro

 08-18 14:44:37.649 17571-17884/bluemage.systems.displaylatencytester E/cv::error()﹕ OpenCV Error: Assertion failed (scn == 3 || scn == 4) in void cv::cvtColor(cv::InputArray, cv::OutputArray, int, int), file /home/reports/ci/slave_desktop/50-SDK/opencv/modules/imgproc/src/color.cpp, line 3737 08-18 14:44:37.650 17571-17884/bluemage.systems.displaylatencytester E/org.opencv.imgproc﹕ imgproc::cvtColor_10() caught cv::Exception: /home/reports/ci/slave_desktop/50-SDK/opencv/modules/imgproc/src/color.cpp:3737: error: (-215) scn == 3 || scn == 4 in function void cv::cvtColor(cv::InputArray, cv::OutputArray, int, int) 08-18 14:44:37.659 17571-17884/bluemage.systems.displaylatencytester E/AndroidRuntime﹕ FATAL EXCEPTION: Thread-4081 Process: bluemage.systems.displaylatencytester, PID: 17571 CvException [org.opencv.core.CvException: cv::Exception: /home/reports/ci/slave_desktop/50-SDK/opencv/modules/imgproc/src/color.cpp:3737: error: (-215) scn == 3 || scn == 4 in function void cv::cvtColor(cv::InputArray, cv::OutputArray, int, int) ] at org.opencv.imgproc.Imgproc.cvtColor_0(Native Method) at org.opencv.imgproc.Imgproc.cvtColor(Imgproc.java:4244) at bluemage.systems.displaylatencytester.testActivity.onCameraFrame(testActivity.java:117) at org.opencv.android.CameraBridgeViewBase.deliverAndDrawFrame(CameraBridgeViewBase.java:387) at org.opencv.android.JavaCameraView$CameraWorker.run(JavaCameraView.java:328) at java.lang.Thread.run(Thread.java:818) 

 if(rgbMat == null){ rgbMat = inputFrame.rgba(); bgrPixel= rgbMat.submat(1,1,2,2).clone(); grayPixel = new Mat(); Imgproc.cvtColor(bgrPixel, grayPixel, Imgproc.COLOR_BGR2GRAY,1); }