add demo code

README.md

@@ -1,6 +1,6 @@
 ---
-title: Sklearn Vector Quantization
-emoji: 📚
+title: sklearn Vector Quantization
+emoji: 📊
 colorFrom: red
 colorTo: green
 sdk: gradio

app.py

@@ -0,0 +1,92 @@
+import gradio as gr
+import matplotlib.pyplot as plt
+from sklearn.preprocessing import KBinsDiscretizer
+from PIL import Image
+import numpy as np
+
+
+def build_init_plot(img_array: np.ndarray) -> tuple[str, plt.Figure]:
+    init_text = (f"The dimension of the image is {img_array.shape}\n"
+          f"The data used to encode the image is of type {img_array.dtype}\n"
+          f"The number of bytes taken in RAM is {img_array.nbytes}")
+
+    fig, ax = plt.subplots(ncols=2, figsize=(12, 4))
+
+    ax[0].imshow(img_array, cmap=plt.cm.gray)
+    ax[0].axis("off")
+    ax[0].set_title("Rendering of the image")
+    ax[1].hist(img_array.ravel(), bins=256)
+    ax[1].set_xlabel("Pixel value")
+    ax[1].set_ylabel("Count of pixels")
+    ax[1].set_title("Distribution of the pixel values")
+    _ = fig.suptitle("Original image")
+
+    return init_text, fig
+
+
+def build_compressed_plot(compressed_image, img_array, sampling: str) -> plt.Figure:
+    compressed_text = (f"The number of bytes taken in RAM is {compressed_image.nbytes}\n"
+          f"Compression ratio: {compressed_image.nbytes / img_array.nbytes}\n"
+          f"Type of the compressed image: {compressed_image.dtype}")
+    
+    sampling = sampling if sampling == "uniform" else "K-Means"
+    
+    fig, ax = plt.subplots(ncols=2, figsize=(12, 4))
+    ax[0].imshow(compressed_image, cmap=plt.cm.gray)
+    ax[0].axis("off")
+    ax[0].set_title("Rendering of the image")
+    ax[1].hist(compressed_image.ravel(), bins=256)
+    ax[1].set_xlabel("Pixel value")
+    ax[1].set_ylabel("Count of pixels")
+    ax[1].set_title("Sub-sampled distribution of the pixel values")
+    _ = fig.suptitle(f"Original compressed using 3 bits and a {sampling} strategy")
+
+    return compressed_text, fig
+
+
+def infer(img_array: np.ndarray, sampling: str):
+    # greyscale_image = input_image.convert("L")
+    # img_array = np.array(greyscale_image)
+
+    #raccoon_face = face(gray=True)
+    init_text, init_fig = build_init_plot(img_array)
+    
+    n_bins = 8
+    encoder = KBinsDiscretizer(
+        n_bins=n_bins, encode="ordinal", strategy=sampling, random_state=0
+    )
+    compressed_image = encoder.fit_transform(img_array.reshape(-1, 1)).reshape(
+        img_array.shape
+    )
+
+    compressed_text, compressed_fig = build_compressed_plot(compressed_image,
+                                                            img_array,
+                                                            sampling)
+
+    bin_edges = encoder.bin_edges_[0]
+    bin_center = bin_edges[:-1] + (bin_edges[1:] - bin_edges[:-1]) / 2
+
+    comparison_fig, ax = plt.subplots()
+    ax.hist(img_array.ravel(), bins=256)
+    color = "tab:orange"
+    for center in bin_center:
+        ax.axvline(center, color=color)
+        ax.text(center - 10, ax.get_ybound()[1] + 100, f"{center:.1f}", color=color)
+
+    return init_text, init_fig, compressed_text, compressed_fig, comparison_fig
+
+
+gr.Interface(
+    title="Vector Quantization with scikit-learn",
+    description="""<p style="text-align: center;">This is an interactive demo for the <a href="https://scikit-learn.org/stable/auto_examples/cluster/plot_face_compress.html">Vector Quantization Tutorial</a> from scikit-learn.
+    </br>You can upload an image and choose from two sampling methods - *uniform* and *kmeans*.</p>""",
+    fn=infer, 
+    inputs=[gr.Image(image_mode="L", label="Input Image"),
+            gr.Dropdown(choices=["uniform", "kmeans"], label="Sampling Method")], 
+    outputs=[gr.Text(label="Original Image Stats"),
+             gr.Plot(label="Original Image Histogram"),
+             gr.Text(label="Compressed Image Stats"), 
+             gr.Plot(label="Compressed Image Histogram"),
+             gr.Plot(label="Pixel Distribution Comparison")],
+    examples=[["examples/hamster.jpeg", "uniform"],
+              ["examples/racoon.png", "kmeans"]]).launch()

requirements.txt

@@ -0,0 +1,3 @@
+matplotlib==3.6.3
+scikit-learn==1.2.1
+scipy