.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "11_demos\itom\dataProcessing\demo_CrossCorrelation_LiveImage.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. note::
        :class: sphx-glr-download-link-note

        :ref:`Go to the end <sphx_glr_download_11_demos_itom_dataProcessing_demo_CrossCorrelation_LiveImage.py>`
        to download the full example code.

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_11_demos_itom_dataProcessing_demo_CrossCorrelation_LiveImage.py:

Cross correlation of images
============================

In this demo the cross-correlation is calculated between two images
acquired via the integrated webcam of your PC.

.. GENERATED FROM PYTHON SOURCE LINES 7-113




.. rst-class:: sphx-glr-script-out

 .. code-block:: none

    Can not open camera with OpenCVGrabber. Probabel root cause: WebCam is not available.
    Used Itom Dummy Grabber instead.






|

.. code-block:: Python


    from itom import dataIO
    from itom import dataObject
    from itom import ui
    import numpy as np
    from numpy import fft


    # some methods
    def acquireImage1():
        g = cam.getAutoGrabbing()
        cam.setAutoGrabbing(False)
        cam.acquire()
        cam.copyVal(image1)
        gui.plot1["source"] = image1
        cam.setAutoGrabbing(g)


    def acquireImage2():
        g = cam.getAutoGrabbing()
        cam.setAutoGrabbing(False)
        cam.acquire()
        cam.copyVal(image2)
        gui.plot2["source"] = image2
        cam.setAutoGrabbing(g)


    def evaluate():
        """determines the offset between image1 and image2
        using cross-correlation and returns a tuple containing
        the shift in x and y-direction"""

        npImg1 = np.array(image1)
        npImg2 = np.array(image2)

        npImg1FFT = fft.fft2(npImg1)
        npImg2FFT = fft.fft2(npImg2)
        ccr = fft.ifft2(npImg1FFT * npImg2FFT.conj())
        ccr_abs = np.abs(ccr)  # np.ascontiguousarray(np.abs(ccr))

        [m, n] = ccr_abs.shape
        max_pos = np.argmax(ccr_abs)
        offset_x = max_pos % n
        offset_y = (max_pos - offset_x) / n

        if offset_x > n / 2:
            offset_x = offset_x - n
        if offset_y > m / 2:
            offset_y = offset_y - m

        gui.lbl_dx["text"] = "dx: " + str(offset_x)
        gui.lbl_dy["text"] = "dy: " + str(offset_y)


    def saveImages():
        filename = ui.getSaveFileName("Filename", filters="IDC (*.idc)", parent=gui)
        if filename:
            saveIDC(filename, {"image1": image1, "image2": image2})


    def loadImages():
        global image1
        global image2
        filename = ui.getOpenFileName("Filename", filters="IDC (*idc)", parent=gui)
        if filename:
            d = loadIDC(filename)
            image1 = d["image1"]
            image2 = d["image2"]
            gui.plot1["source"] = image1
            gui.plot2["source"] = image2


    # open camera (make it before you start this script)
    try:
        cam = dataIO("OpenCVGrabber", colorMode="gray")
    except:
        print("Can not open camera with OpenCVGrabber. Probabel root cause: WebCam is not available.")
        print("Used Itom Dummy Grabber instead.")
        cam = dataIO("DummyGrabber")

    # start camera
    cam.startDevice()

    # create data objects
    image1 = dataObject()
    image2 = dataObject()

    # create gui
    gui = ui("dialog.ui", ui.TYPEWINDOW)
    gui.btnAcquire1.connect("clicked()", acquireImage1)
    gui.btnAcquire2.connect("clicked()", acquireImage2)
    gui.btnLoad.connect("clicked()", loadImages)
    gui.btnSave.connect("clicked()", saveImages)
    gui.btnEval.connect("clicked()", evaluate)

    # show live image in upper plot
    if cam.name() != "FileGrabber":
        cam.setAutoGrabbing(True)
    else:
        cam.setAutoGrabbing(False)

    gui.plotLive["camera"] = cam
    gui.plotLive["keepAspectRatio"] = True
    gui.plotLive["yAxisFlipped"] = True

    gui.show()


.. rst-class:: sphx-glr-timing

   **Total running time of the script:** (0 minutes 0.484 seconds)


.. _sphx_glr_download_11_demos_itom_dataProcessing_demo_CrossCorrelation_LiveImage.py:

.. only:: html

  .. container:: sphx-glr-footer sphx-glr-footer-example

    .. container:: sphx-glr-download sphx-glr-download-jupyter

      :download:`Download Jupyter notebook: demo_CrossCorrelation_LiveImage.ipynb <demo_CrossCorrelation_LiveImage.ipynb>`

    .. container:: sphx-glr-download sphx-glr-download-python

      :download:`Download Python source code: demo_CrossCorrelation_LiveImage.py <demo_CrossCorrelation_LiveImage.py>`

    .. container:: sphx-glr-download sphx-glr-download-zip

      :download:`Download zipped: demo_CrossCorrelation_LiveImage.zip <demo_CrossCorrelation_LiveImage.zip>`