pysdic.Image.evaluate_image_jacobian_dy_at_pixel_points

Image.evaluate_image_jacobian_dy_at_pixel_points(pixel_points)

Evaluate the Jacobian of the image at given pixel points along the \(y\)-axis (rows).

See also

• evaluate_image_at_pixel_points() for evaluating the image at pixel points.

• evaluate_image_jacobian_dx_at_pixel_points() for evaluating the Jacobian of the image at pixel points along the \(x\)-axis (columns).

Pixel out of bounds will be masked and the value at these points will be set to numpy.nan.

Warning

The interpolation function takes pixel_points as input, which are a swap of the camera’s image points ! See documentation of pycvcam (Artezaru/pycvcam) for more details on the name and usage of these points.

You can use pysdic.Camera.image_points_to_pixel_points() to achieve this conversion.

Note

The pixel_points will be converted to numpy.float64 type.

Parameters:

pixel_points (ArrayLike) – The pixel points at which to evaluate the Jacobian. The shape should be (\(N_p\), 2) where \(N_p\) is the number of points and each point is represented by its (row, column) coordinates.

Returns:

The evaluated Jacobian values with shape (\(N_p\),) or (\(N_p\), \(C\)) if color image in float64 dtype. If a pixel point is out of bounds, the corresponding value will be set to numpy.nan.

Return type:

numpy.ndarray