diff --git a/libavfilter/vf_nnedi.c b/libavfilter/vf_nnedi.c
index 4229150668..b273c13944 100644
--- a/libavfilter/vf_nnedi.c
+++ b/libavfilter/vf_nnedi.c
@@ -903,7 +903,7 @@ static void subtract_mean_predictor(PredictorCoefficients *model)
 
     double softmax_means[256]; // Average of individual softmax filters.
     double elliott_means[256]; // Average of individual elliott filters.
-    double mean_filter[48 * 6]; // Pointwise average of all softmax filters.
+    double mean_filter[48 * 6] = { 0 }; // Pointwise average of all softmax filters.
     double mean_bias;
 
     // Quality 1.