avfilter/avf_showspectrum: finally fix log scaler

Signed-off-by: Paul B Mahol <onemda@gmail.com>

diff --git a/libavfilter/avf_showspectrum.c b/libavfilter/avf_showspectrum.c
index 6e73b9e55aa15cc40cac25886d3d1f24116103a7..48d811e2c4279e29ec719bed0a68fd9a50e78204 100644 (file)
--- a/libavfilter/avf_showspectrum.c
+++ b/libavfilter/avf_showspectrum.c
@@ -581,7 +581,7 @@ static int plot_spectrum_column(AVFilterLink *inlink, AVFrame *insamples)
                 a = pow(a, 0.20);
                 break;
             case LOG:
-                a = 1 + log10(FFMAX(FFMIN(1, a), 1e-6)) / 5; // zero = -120dBFS
+                a = 1 + log10(FFMAX(FFMIN(1, a * w), 1e-6)) / 6; // zero = -120dBFS
                 break;
             default:
                 av_assert0(0);