openpiv.pyprocess.get_coordinates

openpiv.pyprocess.get_coordinates(image_size: Tuple[int, int], search_area_size: int, overlap: int, center_on_field: bool = True) → Tuple[ndarray, ndarray][source]

Compute the x, y coordinates of the centers of the interrogation windows. for the SQUARE windows only, see also get_rect_coordinates

the origin (0,0) is like in the image, top left corner positive x is an increasing column index from left to right positive y is increasing row index, from top to bottom

Parameters

  • image_size (two elements tuple) – a two dimensional tuple for the pixel size of the image first element is number of rows, second element is the number of columns.

  • search_area_size (int) – the size of the search area windows, sometimes it’s equal to the interrogation window size in both frames A and B

  • overlap (int = 0 (default is no overlap)) – the number of pixel by which two adjacent interrogation windows overlap.

Returns

  • x (2d np.ndarray) – a two dimensional array containing the x coordinates of the interrogation window centers, in pixels.

  • y (2d np.ndarray) – a two dimensional array containing the y coordinates of the interrogation window centers, in pixels.

    Coordinate system 0,0 is at the top left corner, positive x to the right, positive y from top downwards, i.e. image coordinate system