Hi Emma,

thanks for you reply, I tried already to load the image as gray scale and after your suggestion to convert the image (should be the same) but I got the following error message:

RuntimeWarning: divide by zero encountered in true_divide

  return (2.0 / np.pi) * np.arctan((l2 + l1) / (l2 - l1))

D:\Anaconda\lib\site-packages\skimage\feature\corner.py:421: RuntimeWarning: invalid value encountered in true_divide

  return (2.0 / np.pi) * np.arctan((l2 + l1) / (l2 - l1))

C:/Users/stefanie/PycharmProjects/BluVision/Testing/shape_index.py:27: RuntimeWarning: invalid value encountered in less

  point_y, point_x = np.where(np.abs(s - target) < delta)

C:/Users/stefanie/PycharmProjects/BluVision/Testing/shape_index.py:36: RuntimeWarning: invalid value encountered in less

  point_y_s, point_x_s = np.where(np.abs(s_smooth - target) < delta)

Traceback (most recent call last):

  File "C:/Users/stefanie/PycharmProjects/BluVision/Testing/shape_index.py", line 59, in <module>

    ax2.plot_surface(x, y, image, linewidth=0, alpha=0.5)

  File "D:\Anaconda\lib\site-packages\mpl_toolkits\mplot3d\axes3d.py", line 1612, in plot_surface

    X, Y, Z = np.broadcast_arrays(X, Y, Z)

  File "D:\Anaconda\lib\site-packages\numpy\lib\stride_tricks.py", line 252, in broadcast_arrays

    shape = _broadcast_shape(*args)

  File "D:\Anaconda\lib\site-packages\numpy\lib\stride_tricks.py", line 187, in _broadcast_shape

    b = np.broadcast(*args[:32])

ValueError: shape mismatch: objects cannot be broadcast to a single shape

I would love to open an issue or even to try a pull request. Since this would be the first time, I would need some help and might come back to you if it is OK for you. I notice quite often an uncertainty in the documentation about loading images, so I am glad to help to improve it.

Cheers

Stefanie

Am Di., 1. Jan. 2019 um 22:50 Uhr schrieb Emmanuelle Gouillart <emmanuelle.gouillart@normalesup.org>:

Hi Stefanie,

happy new year to you too :-). I had a quick look at the code of
feature.shape_index, and the function requires a 2D (hence grayscale
image). Can you check that the function works on color.rgb2gray(image)?

This also means that the docstring is incorrect, we should say

image: 2D array

instead of

image : ndarray

Would you mind opening an issue for this? (or even submitting a pull
request?)

All the best
Emma

On Tue, Jan 01, 2019 at 08:48:52PM +0100, Stefanie Lück wrote:
> Hi everybody,

> first of all I wish you a happy new year :)

> I have a problem with the Shape Index example. When I try with my image (shape 
> (778, 1802, 3)) I am getting the following error message:

> Traceback (most recent call last):
>   File "C:/Users/stefanie/PycharmProjects/BluVision/Testing/shape_index.py",
> line 16, in <module>
>     s = shape_index(image)
>   File "D:\Anaconda\lib\site-packages\skimage\feature\corner.py", line 419, in
> shape_index
>     l1, l2 = hessian_matrix_eigvals(H)
> ValueError: too many values to unpack (expected 2)

> System:
> scikit-image 0.14.1
> Windows 10
> Python 3.6

> Any suggestions?
> Thanks
> Stefanie



> _______________________________________________
> scikit-image mailing list -- scikit-image@python.org
> To unsubscribe send an email to scikit-image-leave@python.org
_______________________________________________
scikit-image mailing list -- scikit-image@python.org
To unsubscribe send an email to scikit-image-leave@python.org