diff --git a/src/OpenColorIO/ops/gamma/GammaOpCPU.cpp b/src/OpenColorIO/ops/gamma/GammaOpCPU.cpp
index ace0006ca8..3ebfd67e34 100644
--- a/src/OpenColorIO/ops/gamma/GammaOpCPU.cpp
+++ b/src/OpenColorIO/ops/gamma/GammaOpCPU.cpp
@@ -538,7 +538,10 @@ void GammaMoncurveOpCPUFwd::apply(const void * inImg, void * outImg, long numPix
 
     for(long idx=0; idx<numPixels; ++idx)
     {
-        const float pixel[4] = { in[0], in[1], in[2], in[3] };
+        const float pixel[4] = { std::max(0.0f, in[0]),
+                                 std::max(0.0f, in[1]),
+                                 std::max(0.0f, in[2]),
+                                 std::max(0.0f, in[3]) };
 
         const float data[4] = { std::pow(pixel[0] * red[0] + red[1], red[2]),
                                 std::pow(pixel[1] * grn[0] + grn[1], grn[2]),
@@ -627,7 +630,10 @@ void GammaMoncurveOpCPURev::apply(const void * inImg, void * outImg, long numPix
 
     for(long idx=0; idx<numPixels; ++idx)
     {
-        const float pixel[4] = { in[0], in[1], in[2], in[3] };
+        const float pixel[4] = { std::max(0.0f, in[0]),
+                                 std::max(0.0f, in[1]),
+                                 std::max(0.0f, in[2]),
+                                 std::max(0.0f, in[3]) };
 
         const float data[4] = { std::pow(pixel[0], red[0]) * red[1] - red[2],
                                 std::pow(pixel[1], grn[0]) * grn[1] - grn[2],