--- video/out/cocoa_common.m.orig
+++ video/out/cocoa_common.m
@@ -23,6 +23,7 @@
 #import <AppKit/AppKit.h>
 #include <mach/mach.h>
 #import <CoreVideo/CoreVideo.h>
+#import <AvailabilityMacros.h>
 
 #import "cocoa_common.h"
 #import "video/out/cocoa/window.h"
@@ -50,6 +51,11 @@
 
 #include "common/msg.h"
 
+/* not used on OS X < 10.8 */
+#if !defined(MAC_OS_X_VERSION_10_8) || MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_8
+#define kIOPMAssertionTypePreventUserIdleDisplaySleep CFSTR("PreventUserIdleDisplaySleep")
+#endif
+
 static CVReturn displayLinkCallback(CVDisplayLinkRef displayLink, const CVTimeStamp* now, 
                                     const CVTimeStamp* outputTime, CVOptionFlags flagsIn, 
                                     CVOptionFlags* flagsOut, void* displayLinkContext);