diff --git a/include/media/IOMX.h b/include/media/IOMX.h
index 176f72d..dd13fea 100644
--- a/include/media/IOMX.h
+++ b/include/media/IOMX.h
@@ -38,8 +38,8 @@
 public:
     DECLARE_META_INTERFACE(OMX);
 
-    typedef void *buffer_id;
-    typedef void *node_id;
+    typedef uint32_t buffer_id;
+    typedef uint32_t node_id;
 
     // Given a node_id and the calling process' pid, returns true iff
     // the implementation of the OMX interface lives in the same