diff --git a/libavfilter/af_amerge.c b/libavfilter/af_amerge.c
index 591d672c48..0a0a79fd29 100644
--- a/libavfilter/af_amerge.c
+++ b/libavfilter/af_amerge.c
@@ -27,12 +27,13 @@
 #include "libavutil/bprint.h"
 #include "libavutil/channel_layout.h"
 #include "libavutil/opt.h"
-#include "libswresample/swresample.h" // only for SWR_CH_MAX
 #include "avfilter.h"
 #include "audio.h"
 #include "bufferqueue.h"
 #include "internal.h"
 
+#define SWR_CH_MAX 32
+
 typedef struct {
     const AVClass *class;
     int nb_inputs;