diff --git a/libraries/AP_OpticalFlow/AP_OpticalFlow_CXOF.cpp b/libraries/AP_OpticalFlow/AP_OpticalFlow_CXOF.cpp
index cc59af5562..36278346bf 100644
--- a/libraries/AP_OpticalFlow/AP_OpticalFlow_CXOF.cpp
+++ b/libraries/AP_OpticalFlow/AP_OpticalFlow_CXOF.cpp
@@ -32,7 +32,7 @@
 
 #include <AP_HAL/AP_HAL.h>
 #include "AP_OpticalFlow_CXOF.h"
-#include <AP_Math/edc.h>
+#include <AP_Math/crc.h>
 #include <AP_AHRS/AP_AHRS.h>
 #include <AP_SerialManager/AP_SerialManager.h>
 #include <utility>
diff --git a/libraries/AP_OpticalFlow/AP_OpticalFlow_PX4Flow.cpp b/libraries/AP_OpticalFlow/AP_OpticalFlow_PX4Flow.cpp
index f0e12c2fe4..5d7cc190bb 100644
--- a/libraries/AP_OpticalFlow/AP_OpticalFlow_PX4Flow.cpp
+++ b/libraries/AP_OpticalFlow/AP_OpticalFlow_PX4Flow.cpp
@@ -18,7 +18,7 @@
 
 #include <AP_HAL/AP_HAL.h>
 #include "AP_OpticalFlow_PX4Flow.h"
-#include <AP_Math/edc.h>
+#include <AP_Math/crc.h>
 #include <AP_AHRS/AP_AHRS.h>
 #include <AP_HAL/I2CDevice.h>
 #include <utility>
diff --git a/libraries/AP_OpticalFlow/AP_OpticalFlow_Pixart.cpp b/libraries/AP_OpticalFlow/AP_OpticalFlow_Pixart.cpp
index a3311e3bf0..4ca794d555 100644
--- a/libraries/AP_OpticalFlow/AP_OpticalFlow_Pixart.cpp
+++ b/libraries/AP_OpticalFlow/AP_OpticalFlow_Pixart.cpp
@@ -21,7 +21,7 @@
  */
 
 #include <AP_HAL/AP_HAL.h>
-#include <AP_Math/edc.h>
+#include <AP_Math/crc.h>
 #include <AP_AHRS/AP_AHRS.h>
 #include <utility>
 #include "OpticalFlow.h"