diff --git a/gst-libs/gst/codecparsers/gstmpeg4parser.h b/gst-libs/gst/codecparsers/gstmpeg4parser.h
index be17bb418f..7916c28898 100644
--- a/gst-libs/gst/codecparsers/gstmpeg4parser.h
+++ b/gst-libs/gst/codecparsers/gstmpeg4parser.h
@@ -24,6 +24,11 @@
 #include <gst/gst.h>
 #include <gst/codecparsers/codecparsers-prelude.h>
 
+#ifndef GST_USE_UNSTABLE_API
+#warning "The MPEG4 parsing library is unstable API and may change in future."
+#warning "You can define GST_USE_UNSTABLE_API to avoid this warning."
+#endif
+
 G_BEGIN_DECLS
 
 typedef struct _GstMpeg4VisualObjectSequence    GstMpeg4VisualObjectSequence;
diff --git a/gst-libs/gst/codecparsers/gstvp8parser.h b/gst-libs/gst/codecparsers/gstvp8parser.h
index 23a432d69e..2e56e6fb29 100644
--- a/gst-libs/gst/codecparsers/gstvp8parser.h
+++ b/gst-libs/gst/codecparsers/gstvp8parser.h
@@ -27,6 +27,11 @@
 #include <gst/gst.h>
 #include <gst/codecparsers/codecparsers-prelude.h>
 
+#ifndef GST_USE_UNSTABLE_API
+#warning "The VP8 parsing library is unstable API and may change in future."
+#warning "You can define GST_USE_UNSTABLE_API to avoid this warning."
+#endif
+
 G_BEGIN_DECLS
 
 typedef struct _GstVp8FrameHdr          GstVp8FrameHdr;