image.cpp: fix MAE computation

Fixes #442.
mmp · Oct 9, 2024 · 710bc1a · 710bc1a
1 parent 2cc9d5b
commit 710bc1a
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/pbrt/util/image.cpp b/src/pbrt/util/image.cpp
@@ -557,7 +557,7 @@ ImageChannelValues Image::MAE(const ImageChannelDesc &desc, const Image &ref,
             ImageChannelValues vref = ref.GetChannels({x, y}, refDesc);
 
             for (int c = 0; c < desc.size(); ++c) {
-                double error = double(v[c]) - double(vref[c]);
+                double error = std::abs(double(v[c]) - double(vref[c]));
                 if (IsInf(error))
                     continue;
                 sumError[c] += error;