Remove empty folder in analysis/compression_analysis (#897)

* Add compression_analysis

removing analysis/compression_analysis to just compression_analysis

* Delete PSNR-example-base.png

* Delete PSNR-example-comp-10.jpg

* Delete compressed_image.png

* Delete example_image.jpg

* Delete example_wikipedia_image.jpg

* Delete original_image.png

* Delete psnr.py

compression_analysis/psnr.py

@@ -0,0 +1,40 @@
+"""
+	Peak signal-to-noise ratio - PSNR - https://en.wikipedia.org/wiki/Peak_signal-to-noise_ratio
+    Soruce: https://tutorials.techonical.com/how-to-calculate-psnr-value-of-two-images-using-python/
+"""
+
+import math
+import os
+
+import cv2
+import numpy as np
+
+def psnr(original, contrast):
+    mse = np.mean((original - contrast) ** 2)
+    if mse == 0:
+        return 100
+    PIXEL_MAX = 255.0
+    PSNR = 20 * math.log10(PIXEL_MAX / math.sqrt(mse))
+    return PSNR
+
+
+def main():
+    dir_path = os.path.dirname(os.path.realpath(__file__))
+    # Loading images (original image and compressed image)
+    original = cv2.imread(os.path.join(dir_path, 'original_image.png'))
+    contrast = cv2.imread(os.path.join(dir_path, 'compressed_image.png'), 1)
+
+    original2 = cv2.imread(os.path.join(dir_path, 'PSNR-example-base.png'))
+    contrast2 = cv2.imread(os.path.join(dir_path, 'PSNR-example-comp-10.jpg'), 1)
+
+    # Value expected: 29.73dB
+    print("-- First Test --")
+    print(f"PSNR value is {psnr(original, contrast)} dB")
+
+    # # Value expected: 31.53dB (Wikipedia Example)
+    print("\n-- Second Test --")
+    print(f"PSNR value is {psnr(original2, contrast2)} dB")
+
+
+if __name__ == '__main__':
+    main()