How to use .npz file

[priyamp23]

After sampling, a .npz file is being created. Please let me know - how to handle that and how to create images out of it so that I can see what samples are being created?

[isaacjones99]

You may have worked this out by now, but .npz files are created by the Numpy library and can be loaded using np.load. The data inside is stored in a dictionary-like structure, and you can access it using keys. In this case the keys will be arr_0 and arr_1, where the first contains a list of images and the second contains labels (if class conditioning was used).

You can check what keys are saved within a .npz file with list(data.keys()).

Here's an example of how to load and visualize the samples using Matplotlib:

import numpy as np  # Import numpy
import matplotlib.pyplot as plt  # Import matplotlib

samples_path = "tmp/samples_4x128x128x3.npz"  # Path to the samples .npz file

# Load the .npz file
data = np.load(samples_path)

# Access images and labels
images = data.get('arr_0') 
labels = data.get('arr_1') 

# Visualize the samples
fig, axes = plt.subplots(nrows=1, ncols=4, figsize=(12, 6))

for i, ax in enumerate(axes.flatten()):
    ax.imshow(images[i])
    if labels is not None:
        ax.set_title(labels[i])
    ax.set_axis_off()

plt.tight_layout()
plt.show()

In this example I've set the number of columns to four because that's how many samples I generated but you can increase the number of rows and columns to display more samples.