using macro define

app/src/main/cpp/visualizer/execute_fft.cpp

@@ -202,11 +202,11 @@ int init_visualizer(filter_sys_t *p_filter)
     p_filter->data = nullptr;
     p_filter->data_size = 0;
     p_filter->nb_samples = 0;
-    if (FIXED_FFT) {
-        p_filter->out_samples = 1 << 9;
-    } else {
-        p_filter->out_samples = FFT_BUFFER_SIZE;
-    }
+#ifdef FIXED_FFT
+    p_filter->out_samples = 512;
+#else
+    p_filter->out_samples = FFT_BUFFER_SIZE;
+#endif
     p_filter->output = (int8_t *) (malloc(p_filter->out_samples * sizeof(int8_t)));
     return 0;
 }
@@ -386,9 +386,9 @@ release:
 
 void fft_once(filter_sys_t *p_sys)
 {
-    if (FIXED_FFT) {
-        fft_fixed(p_sys);
-    } else {
-        fft_float(p_sys);
-    }
+#ifdef FIXED_FFT
+    fft_fixed(p_sys);
+#else
+    fft_float(p_sys);
+#endif
 }