diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h
index 086e9fed36..9a6b277c2a 100644
--- a/libavfilter/avfilter.h
+++ b/libavfilter/avfilter.h
@@ -199,7 +199,7 @@ typedef struct AVFilterBufferRef {
  * Copy properties of src to dst, without copying the actual data
  */
 attribute_deprecated
-void avfilter_copy_buffer_ref_props(AVFilterBufferRef *dst, AVFilterBufferRef *src);
+void avfilter_copy_buffer_ref_props(AVFilterBufferRef *dst, const AVFilterBufferRef *src);
 
 /**
  * Add a new reference to a buffer.
diff --git a/libavfilter/buffer.c b/libavfilter/buffer.c
index a62618440b..885e9caf96 100644
--- a/libavfilter/buffer.c
+++ b/libavfilter/buffer.c
@@ -150,7 +150,7 @@ int avfilter_copy_frame_props(AVFilterBufferRef *dst, const AVFrame *src)
     return 0;
 }
 
-void avfilter_copy_buffer_ref_props(AVFilterBufferRef *dst, AVFilterBufferRef *src)
+void avfilter_copy_buffer_ref_props(AVFilterBufferRef *dst, const AVFilterBufferRef *src)
 {
     // copy common properties
     dst->pts             = src->pts;