patchify 0.2

A library that helps you split image into small, overlappable patches, and merge patches back into the original image.

patchify

patchfy can split images into small overlappable patches by given patch cell size, and merge patches into original image.

This library provides two functions: patchify, unpatchify.

Usage:

patchify(image_to_patch, patch_shape, step=1)

Example:
2D images:

#This will split the image into small images of shape [3,3]
patches = patchify(image, (3, 3), step=1)

3D images:

#This will split the image into small images of shape [3,3,3]
patches = patchify(image, (3, 3, 3), step=1)

Patches can merged using:

unpatchify(patches_to_merge, merged_image_size)

Example:

reconstructed_image = unpatchify(patches, image.shape)

This will reconstruct the original image that was patchified in previous code.

A full example:

2D images

import numpy as np
from patchify import patchify, unpatchify

image = np.array([[1,2,3,4], [5,6,7,8], [9,10,11,12]])

patches = patchify(image, (2,2), step=1) # split image into 2*3 small 2*2 patches.

assert patches.shape == (2, 3, 2, 2)
reconstructed_image = unpatchify(patches, image.shape)

assert (reconstructed_image == image).all()

3D images

import numpy as np
from patchify import patchify, unpatchify

image = np.random.rand(512,512,3)

patches = patchify(image, (2,2,3), step=1) # patch shape [2,2,3]
print(patches.shape) # (511, 511, 1, 2, 2, 3). Total patches created: 511x511x1

assert patches.shape == (511, 511, 1, 2, 2, 3)
reconstructed_image = unpatchify(patches, image.shape)
print(reconstructed_image.shape) # (512, 512, 3)

assert (reconstructed_image == image).all()