diff --git a/libavcodec/av1dec.c b/libavcodec/av1dec.c
index 6114cb78e6..4dcde234c6 100644
--- a/libavcodec/av1dec.c
+++ b/libavcodec/av1dec.c
@@ -177,7 +177,7 @@ static uint8_t get_shear_params_valid(AV1DecContext *s, int idx)
     int16_t alpha, beta, gamma, delta, divf, divs;
     int64_t v, w;
     int32_t *param = &s->cur_frame.gm_params[idx][0];
-    if (param[2] < 0)
+    if (param[2] <= 0)
         return 0;
 
     alpha = av_clip_int16(param[2] - (1 << AV1_WARPEDMODEL_PREC_BITS));