diff --git a/unittest/CMakeLists.txt b/unittest/CMakeLists.txt
index bb1de53..2493a74 100644
--- a/unittest/CMakeLists.txt
+++ b/unittest/CMakeLists.txt
@@ -4,5 +4,6 @@ add_subdirectory(IlmImfCtl)
 if (CTL_BUILD_TOOLS)
     add_subdirectory(ctlrender)
     add_subdirectory(exrdpx)
+    add_subdirectory(exr_ctl_exr)
 endif()
 
diff --git a/unittest/exr_ctl_exr/CMakeLists.txt b/unittest/exr_ctl_exr/CMakeLists.txt
new file mode 100644
index 0000000..34189cc
--- /dev/null
+++ b/unittest/exr_ctl_exr/CMakeLists.txt
@@ -0,0 +1,31 @@
+if(NOT DEFINED EXR_CTL_EXR_BUILD_DIR)
+    set(EXR_CTL_EXR_BUILD_DIR "${CMAKE_BINARY_DIR}/OpenEXR_CTL/exr_ctl_exr")
+    message("exr_ctl_exr build director: ${EXR_CTL_EXR_BUILD_DIR}")
+endif()
+
+if(NOT DEFINED EXR_CTL_EXR_EXECUTABLE_PATH)
+    set(EXR_CTL_EXR_EXECUTABLE_PATH "${EXR_CTL_EXR_BUILD_DIR}/exr_ctl_exr")
+    message("exr_ctl_exr test executable: ${EXR_CTL_EXR_EXECUTABLE_PATH}")
+endif()
+
+set(EXR_CTL_EXR_OUTPUT_FOLDER "${CMAKE_BINARY_DIR}/unittest/exr_ctl_exr/output")
+message("exr_ctl_exr test output folder will be created at: ${EXR_CTL_EXR_OUTPUT_FOLDER}")
+add_custom_target(exr-ctl-exr-build-time-make-directory ALL
+    COMMAND ${CMAKE_COMMAND} -E make_directory ${EXR_CTL_EXR_OUTPUT_FOLDER})
+
+set(TEST_FILES "${PROJECT_SOURCE_DIR}/unittest/exr_ctl_exr")
+
+# copy CTL files to build folder
+add_custom_target(
+    exr-ctl-exr-build-time-copy-CTL-file1 ALL
+  COMMAND ${CMAKE_COMMAND} -E copy 
+    ${TEST_FILES}/change_saturation.ctl 
+    "${EXR_CTL_EXR_BUILD_DIR}")
+
+if(OpenEXR_FOUND)
+
+    add_test(NAME "exr-ctl-exr-noargs" COMMAND ${EXR_CTL_EXR_EXECUTABLE_PATH} -C change_saturation "${TEST_FILES}/marci-512.exr" "${EXR_CTL_EXR_OUTPUT_FOLDER}/exr-ctl-exr-noargs.exr" WORKING_DIRECTORY "${EXR_CTL_EXR_BUILD_DIR}")
+    # set CTL_MODULE_PATH environment variable before running exr_ctl_exr
+    #set_property(TEST "exr-ctl-exr-noargs" PROPERTY ENVIRONMENT_MODIFICATION "CTL_MODULE_PATH=./")
+
+endif()
diff --git a/unittest/exr_ctl_exr/change_saturation.ctl b/unittest/exr_ctl_exr/change_saturation.ctl
new file mode 100644
index 0000000..33914a5
--- /dev/null
+++ b/unittest/exr_ctl_exr/change_saturation.ctl
@@ -0,0 +1,131 @@
+///////////////////////////////////////////////////////////////////////////
+// Copyright (c) 2013 Academy of Motion Picture Arts and Sciences 
+// ("A.M.P.A.S."). Portions contributed by others as indicated.
+// All rights reserved.
+// 
+// A worldwide, royalty-free, non-exclusive right to copy, modify, create
+// derivatives, and use, in source and binary forms, is hereby granted, 
+// subject to acceptance of this license. Performance of any of the 
+// aforementioned acts indicates acceptance to be bound by the following 
+// terms and conditions:
+//
+//  * Copies of source code, in whole or in part, must retain the 
+//    above copyright notice, this list of conditions and the 
+//    Disclaimer of Warranty.
+//
+//  * Use in binary form must retain the above copyright notice, 
+//    this list of conditions and the Disclaimer of Warranty in the
+//    documentation and/or other materials provided with the distribution.
+//
+//  * Nothing in this license shall be deemed to grant any rights to 
+//    trademarks, copyrights, patents, trade secrets or any other 
+//    intellectual property of A.M.P.A.S. or any contributors, except 
+//    as expressly stated herein.
+//
+//  * Neither the name "A.M.P.A.S." nor the name of any other 
+//    contributors to this software may be used to endorse or promote 
+//    products derivative of or based on this software without express 
+//    prior written permission of A.M.P.A.S. or the contributors, as 
+//    appropriate.
+// 
+// This license shall be construed pursuant to the laws of the State of 
+// California, and any disputes related thereto shall be subject to the 
+// jurisdiction of the courts therein.
+//
+// Disclaimer of Warranty: THIS SOFTWARE IS PROVIDED BY A.M.P.A.S. AND 
+// CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, 
+// BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS 
+// FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT ARE DISCLAIMED. IN NO 
+// EVENT SHALL A.M.P.A.S., OR ANY CONTRIBUTORS OR DISTRIBUTORS, BE LIABLE 
+// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, RESITUTIONARY, 
+// OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 
+// THE POSSIBILITY OF SUCH DAMAGE.
+//
+// WITHOUT LIMITING THE GENERALITY OF THE FOREGOING, THE ACADEMY 
+// SPECIFICALLY DISCLAIMS ANY REPRESENTATIONS OR WARRANTIES WHATSOEVER 
+// RELATED TO PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS IN THE ACADEMY 
+// COLOR ENCODING SYSTEM, OR APPLICATIONS THEREOF, HELD BY PARTIES OTHER 
+// THAN A.M.P.A.S., WHETHER DISCLOSED OR UNDISCLOSED.
+///////////////////////////////////////////////////////////////////////////
+
+//
+// Function change_saturation() saturates or desaturates an RGB image by
+// converting the pixels to CIELAB, multiplying the a* and b* components
+// by a caller-supplied factor, sScale, and converting back to RGB.
+//
+// Parameters:
+//
+//	R, G, B			Input pixel value
+//
+//	ROut, GOut, BOut	Output pixel value
+//
+//	sScale			Saturation scale factor:
+//				sScale > 1 increases saturation,
+//				0 <= sScale < 1 decreases saturation,
+//
+//	chromaticities		CIE (x,y) coordinates of the primaries
+//				and white point for the input and output
+//				pixels
+//
+//	whiteLuminance		Luminance of pixels with R = G = B = 1
+//
+//	adoptedNeutral		CIE (x,y) coordinates of the white stimulus
+//				for RGB-to-LAB and LAB-to-RGB conversion.
+//				Decreasing or increasing saturation makes
+//				the pixel colors move towards or away from
+//				the adoptedNeutral value.
+//
+
+void
+change_saturation
+    (output varying half ROut,
+     output varying half GOut,
+     output varying half BOut,
+     varying half R,
+     varying half G,
+     varying half B,
+     float adoptedNeutral[2],
+     Chromaticities chromaticities,
+     float whiteLuminance = 1.0,
+     float sScale = 1.0)
+{
+    //
+    // Compute the XYZ coordinates of the white stimulus.
+    //
+
+    float XYZn[3];
+    XYZn[0] = adoptedNeutral[0] * whiteLuminance / adoptedNeutral[1];
+    XYZn[1] = whiteLuminance;
+    XYZn[2] = whiteLuminance / adoptedNeutral[1] - XYZn[0] - whiteLuminance;
+
+    //
+    // Convert input RGB value first to XYZ, then to LAB
+    //
+
+    float toXYZ[4][4] = RGBtoXYZ (chromaticities, whiteLuminance);
+    float RGB[3] = {R, G, B};
+    float XYZ[3] = mult_f3_f44 (RGB, toXYZ);
+    float Lab[3] = XYZtoLab (XYZ, XYZn);
+
+    //
+    // Change saturation by scaling the a* and b* coordinates.
+    //
+
+    Lab[1] = Lab[1] * sScale;
+    Lab[2] = Lab[2] * sScale;
+
+    //
+    // Convert back to XYZ and then to RGB
+    //
+
+    XYZ = LabtoXYZ (Lab, XYZn);
+    float toRGB[4][4] = XYZtoRGB (chromaticities, whiteLuminance);
+    RGB = mult_f3_f44 (XYZ, toRGB);
+    ROut = RGB[0];
+    GOut = RGB[1];
+    BOut = RGB[2];
+}
diff --git a/unittest/exr_ctl_exr/marci-512.exr b/unittest/exr_ctl_exr/marci-512.exr
new file mode 100644
index 0000000..04ce5a5
Binary files /dev/null and b/unittest/exr_ctl_exr/marci-512.exr differ