From 16e03179ee3952b733d555b8b4f9d198fe145a45 Mon Sep 17 00:00:00 2001
From: Marcin Kostrzewski <komar86311@gmail.com>
Date: Sun, 29 Jan 2023 22:51:25 +0100
Subject: [PATCH] Structural similarity comparison method

---
 comparisons.py   | 6 +++++-
 main.py          | 3 ++-
 requirements.txt | 3 ++-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/comparisons.py b/comparisons.py
index 7ff6a72..a4defff 100644
--- a/comparisons.py
+++ b/comparisons.py
@@ -1,6 +1,6 @@
 import cv2
 import numpy as np
-
+from skimage.metrics import structural_similarity
 
 def histogram_comparison(data_a: np.ndarray, data_b: np.ndarray) -> dict:
   hsv_a = cv2.cvtColor(data_a, cv2.COLOR_BGR2HSV)
@@ -23,3 +23,7 @@ def histogram_comparison(data_a: np.ndarray, data_b: np.ndarray) -> dict:
     'intersection': cv2.compareHist(hist_a, hist_b, 2),
     'bhattacharyya-distance': cv2.compareHist(hist_a, hist_b, 3),
   }
+
+
+def structural_similarity_index(data_a: np.ndarray, data_b: np.ndarray) -> float:
+  return structural_similarity(cv2.cvtColor(data_a, cv2.COLOR_BGR2GRAY), cv2.cvtColor(data_b, cv2.COLOR_BGR2GRAY))
diff --git a/main.py b/main.py
index 1fb59c7..8046255 100644
--- a/main.py
+++ b/main.py
@@ -3,7 +3,7 @@ import cv2
 import numpy as np
 import matplotlib.pyplot as plt
 
-from comparisons import histogram_comparison
+from comparisons import histogram_comparison, structural_similarity_index
 
 # Allows imports from the style transfer submodule
 sys.path.append('DCT-Net')
@@ -44,6 +44,7 @@ def compare_with_anime_characters(data: np.ndarray) -> int:
   data_rescaled = cv2.resize(data, example_face.shape[:2])
   plot_two_images(example_face, data_rescaled)
   print(histogram_comparison(data_rescaled, example_face))
+  print(f'structural-similarity: {structural_similarity_index(data_rescaled, example_face)}')
 
 
 def transfer_to_anime(img: np.ndarray):
diff --git a/requirements.txt b/requirements.txt
index 45b2c87..33c4fb9 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -7,4 +7,5 @@ beautifulsoup4==4.11.1
 lxml==4.9.2
 opencv-python==4.7.0.68
 torch==1.13.1
-matplotlib==3.6.3
\ No newline at end of file
+matplotlib==3.6.3
+scikit-image==0.19.3
\ No newline at end of file