From ee7353cfde7a4dc88e607d6730fd9463b76451c3 Mon Sep 17 00:00:00 2001
From: Benjamin Loison <12752145+Benjamin-Loison@users.noreply.github.com>
Date: Sat, 27 Apr 2024 15:58:29 +0200
Subject: [PATCH] Correct `iterativeMean` implementation for images

Otherwise get:

```
Traceback (most recent call last):
  File "/home/benjamin/robust_image_source_identification_on_modern_smartphones/datasets/raise/./extract_noise.py", line 148, in <module>
    treatImage(imageFileName, color = color)
  File "/home/benjamin/robust_image_source_identification_on_modern_smartphones/datasets/raise/./extract_noise.py", line 114, in treatImage
    estimatedPrnuIterativeMean.add(imageNoiseNpArray)
  File "/home/benjamin/robust_image_source_identification_on_modern_smartphones/datasets/raise/utils.py", line 34, in add
    self.mean = ((self.mean * self.numberOfElementsInMean) + element) / (self.numberOfElementsInMean + 1)
                  ~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
TypeError: unsupported operand type(s) for *: 'NoneType' and 'int'
```
---
 datasets/raise/utils.py | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/datasets/raise/utils.py b/datasets/raise/utils.py
index 258c80a..1ce8916 100644
--- a/datasets/raise/utils.py
+++ b/datasets/raise/utils.py
@@ -31,5 +31,8 @@ class iterativeMean:
     numberOfElementsInMean = 0
 
     def add(self, element):
-        self.mean = ((self.mean * self.numberOfElementsInMean) + element) / (self.numberOfElementsInMean + 1)
-        self.numberOfElementsInMean += 1
\ No newline at end of file
+        if self.mean is None:
+            self.mean = element
+        else:
+            self.mean = ((self.mean * self.numberOfElementsInMean) + element) / (self.numberOfElementsInMean + 1)
+        self.numberOfElementsInMean += 1