diff --git a/rawimage.cpp b/rawimage.cpp
index 36ec0f2..c4878d1 100644
--- a/rawimage.cpp
+++ b/rawimage.cpp
@@ -243,11 +243,6 @@ void calcStats(const T *data, size_t n, size_t w, RawImage::Stats &stats)
     {
         T mmin = *std::min_element(min, min + 4);
         T mmax = *std::max_element(max, max + 4);
-        for(int i=0; i<4; i++)
-        {
-            histogram[i].clear();
-            histogram[i].resize(histSize, 0);
-        }
 
         T a = 1.0 / (mmax - mmin);
         T b = -mmin / (mmax - mmin);
@@ -261,6 +256,12 @@ void calcStats(const T *data, size_t n, size_t w, RawImage::Stats &stats)
         // calculate histogram again
         if(mmin < 0.0 || mmax > 1.0)
         {
+            for(int i=0; i<4; i++)
+            {
+                histogram[i].clear();
+                histogram[i].resize(histSize, 0);
+            }
+
             for(size_t i = 0; i < n; i++)
             {
                 histFunc(data[i*ch], 0);