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Elastic transformation of an image in Python
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import numpy as np | |
from scipy.ndimage.interpolation import map_coordinates | |
from scipy.ndimage.filters import gaussian_filter | |
def elastic_transform(image, alpha, sigma, random_state=None): | |
"""Elastic deformation of images as described in [Simard2003]_. | |
.. [Simard2003] Simard, Steinkraus and Platt, "Best Practices for | |
Convolutional Neural Networks applied to Visual Document Analysis", in | |
Proc. of the International Conference on Document Analysis and | |
Recognition, 2003. | |
""" | |
if random_state is None: | |
random_state = np.random.RandomState(None) | |
shape = image.shape | |
dx = gaussian_filter((random_state.rand(*shape) * 2 - 1), sigma, mode="constant", cval=0) * alpha | |
dy = gaussian_filter((random_state.rand(*shape) * 2 - 1), sigma, mode="constant", cval=0) * alpha | |
dz = np.zeros_like(dx) | |
x, y, z = np.meshgrid(np.arange(shape[0]), np.arange(shape[1]), np.arange(shape[2])) | |
print x.shape | |
indices = np.reshape(y+dy, (-1, 1)), np.reshape(x+dx, (-1, 1)), np.reshape(z, (-1, 1)) | |
distored_image = map_coordinates(image, indices, order=1, mode='reflect') | |
return distored_image.reshape(image.shape) |
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which augement did you apply for dataset @bigfred76