Update Frame.h

Author: jonoomph

include/Frame.h

@@ -250,7 +250,7 @@ namespace openshot
 		const unsigned char* GetPixels(int row);
 
 		/// Check a specific pixel color value (returns True/False)
-		bool CheckPixel(int row, int col, int red, int green, int blue, int alpha);
+		bool CheckPixel(int row, int col, int red, int green, int blue, int alpha, int threshold);
 
 		/// Get height of image
 		int GetHeight();