diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 28eed989be75e15a3538ccd838b5a947e223caa9..5cc0a6461b8ee1751d199b6b0cb1e9b0f9bebd16 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -4,7 +4,7 @@ SET(sources firewirecamera.cpp firewireserver.cpp firewireexceptions.cpp ptg_cam
 SET(headers firewirecamera.h firewireserver.h firewireexceptions.h ptg_camera.h bumblebee.h ladybug.h)
 
 #find the cv support and set HAVE_OPENCV_H for the conditional compilation
-FIND_PACKAGE(OpenCV)
+FIND_PACKAGE(OpenCV 2.4)
 
 if (OpenCV_FOUND) 
   if (${OpenCV_VERSION_MAJOR} GREATER 1)
diff --git a/src/bumblebee.cpp b/src/bumblebee.cpp
index 08d50e866450522c4ecddb4904dff1e21d2117b2..6cbcfe5d1775ae4b3550765e2d796728651b139f 100755
--- a/src/bumblebee.cpp
+++ b/src/bumblebee.cpp
@@ -4,6 +4,7 @@
 #include <string.h>
 #include <fcntl.h>
 #include <math.h>
+#include <unistd.h>
 
 CBumblebee::CBumblebee(dc1394_t *firewire,uint64_t camera_id):CPTGCamera(firewire,camera_id)
 {
diff --git a/src/ladybug.cpp b/src/ladybug.cpp
index a0831ecbf1e984f4864f8f580d907d5ece3f92b0..7364aaf2c6d94f7383b13f79b45199a20a9b59ec 100755
--- a/src/ladybug.cpp
+++ b/src/ladybug.cpp
@@ -4,6 +4,7 @@
 #include <string.h>
 #include <fcntl.h>
 #include <math.h>
+#include <unistd.h>
 
 CLadyBug::CLadyBug(dc1394_t *firewire,uint64_t camera_id):CPTGCamera(firewire,camera_id)
 {