diff --git a/libavcodec/aacenc_utils.h b/libavcodec/aacenc_utils.h
index 41a62961e1..07f733746b 100644
--- a/libavcodec/aacenc_utils.h
+++ b/libavcodec/aacenc_utils.h
@@ -28,6 +28,7 @@
 #ifndef AVCODEC_AACENC_UTILS_H
 #define AVCODEC_AACENC_UTILS_H
 
+#include "libavutil/internal.h"
 #include "aac.h"
 #include "aacenctab.h"
 #include "aactab.h"
@@ -122,7 +123,10 @@ static inline float find_form_factor(int group_len, int swb_size, float thresh,
             if (s >= ethresh) {
                 nzl += 1.0f;
             } else {
-                nzl += powf(s / ethresh, nzslope);
+                if (nzslope == 2.f)
+                    nzl += (s / ethresh) * (s / ethresh);
+                else
+                    nzl += ff_fast_powf(s / ethresh, nzslope);
             }
         }
         if (e2 > thresh) {
diff --git a/libavutil/internal.h b/libavutil/internal.h
index da76ca26d3..340e18bc5d 100644
--- a/libavutil/internal.h
+++ b/libavutil/internal.h
@@ -314,6 +314,22 @@ static av_always_inline float ff_exp10f(float x)
     return exp2f(M_LOG2_10 * x);
 }
 
+/**
+ * Compute x^y for floating point x, y. Note: this function is faster than the
+ * libm variant due to mainly 2 reasons:
+ * 1. It does not handle any edge cases. In particular, this is only guaranteed
+ * to work correctly for x > 0.
+ * 2. It is not as accurate as a standard nearly "correctly rounded" libm variant.
+ * @param x base
+ * @param y exponent
+ * @return x^y
+ */
+static av_always_inline float ff_fast_powf(float x, float y)
+{
+    return expf(logf(x) * y);
+}
+
+
 /**
  * A wrapper for open() setting O_CLOEXEC.
  */