Added FFT methods

docs/project-demo/demo-material/helper-functions.py

@@ -4,7 +4,10 @@ from os.path import abspath
 import datetime
 import matplotlib.pyplot as plt
 from tqdm import tqdm
-import random
+import numpy as np
+import random 
+from PIL import Image
+import requests
 
 # Export's video frames
 def video_to_frames(path):
@@ -79,4 +82,41 @@ def list_dir_abs(directory):
 
 def pickRandomNum(paths, num):
     ranPaths = random.choices(paths, k=num)
-    return ranPaths
+    return ranPaths
+
+def showImage(path):
+    image = cv2.imread(path)
+    image = cv2.cvtColor(image, cv2.COLOR_BGR2RGB)
+    plt.imshow(image)
+    plt.show()
+
+def showDiscreteFFT(image):
+    fftImage = np.fft.fft2(image)
+    fftShift = np.fft.fftshift(fftImage)
+    magnitude = 20 * np.log(np.abs(fftShift))
+    
+    fig = plt.figure(figsize=(15, 6))
+    fig.add_subplot(1, 2, 1)
+    plt.imshow(image, cmap="gray")
+    fig.add_subplot(1, 2, 2)
+    plt.imshow(magnitude, cmap="gray")
+    fig.tight_layout()
+    plt.show()
+
+def loadImageFromURL(url):
+    response = requests.get(url)
+    image = Image.open(requests.get(url, stream=True).raw)
+    return image
+
+def PILToNumpy(image):
+    image = np.array(image)
+    return image
+
+def URL2FFT(url):
+    image = loadImageFromURL(url)
+    if image.mode == "RGB":
+        image = PILToNumpy(image)
+        image = cv2.cvtColor(image, cv2.COLOR_RGB2GRAY)
+    else:
+        image = PILToNumpy(image)
+    showDiscreteFFT(image)