diff --git a/src/main.cpp b/src/main.cpp
index 74fec1a..b1aeb6c 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -289,9 +289,12 @@ int perfromOperation(int operation, char** fileNames, const Config& config)
 			return -1;
 		}
 		
-		cvtColor(inImages[0], inImages[0], cv::COLOR_BGR2GRAY);
+		if(inImages[0].channels() > 1)
+			cvtColor(inImages[0], inImages[0], cv::COLOR_BGR2GRAY);
+		if(inImages[0].type() != CV_32FC1)
 		inImages[0].convertTo(inImages[0], CV_32F);
 		
+		Log(Log::DEBUG)<<"applyCurve";
 		applyCurve(inImages[0], curve);
 	}
 	else if(operation == CREATE_CURVE)