From edfc6bde788569e82488f44ccde8f905422962b3 Mon Sep 17 00:00:00 2001
From: Pavel Krajcevski <pavel@cs.unc.edu>
Date: Tue, 26 Aug 2014 13:34:35 -0400
Subject: [PATCH] Be a little more defensive about calculating SSIM

---
 Base/src/Image.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Base/src/Image.cpp b/Base/src/Image.cpp
index ea18b36..7240e7a 100644
--- a/Base/src/Image.cpp
+++ b/Base/src/Image.cpp
@@ -316,6 +316,11 @@ double Image<PixelType>::ComputeSSIM(Image<PixelType> *other) {
   const uint32 filterSz = 11;
   const double filterSigma = 1.5;
 
+  if(img1.GetWidth() < filterSz || img1.GetHeight() < filterSz ||
+     img2.GetWidth() < filterSz || img2.GetHeight() < filterSz) {
+    return -1.0;
+  }
+
   Image<IPixel> mu1 = FilterValid(img1, filterSz, filterSigma);
   Image<IPixel> mu2 = FilterValid(img2, filterSz, filterSigma);