[FFmpeg-cvslog] avfilter/af_drmeter: improve measurement precision

[Paul B Mahol]

ffmpeg | branch: master | Paul B Mahol <onemda at gmail.com> | Thu Nov 18 22:14:11 2021 +0100| [8c150d3d9794c29a54bbdf2f2a88066277c7197e] | committer: Paul B Mahol

avfilter/af_drmeter: improve measurement precision

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=8c150d3d9794c29a54bbdf2f2a88066277c7197e
---

 libavfilter/af_drmeter.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/libavfilter/af_drmeter.c b/libavfilter/af_drmeter.c
index 1ff769a29f..6e0d80a3f1 100644
--- a/libavfilter/af_drmeter.c
+++ b/libavfilter/af_drmeter.c
@@ -26,7 +26,7 @@
 #include "avfilter.h"
 #include "internal.h"
 
-#define BINS 10000
+#define BINS 32768
 
 typedef struct ChannelStats {
     uint64_t nb_samples;
@@ -75,8 +75,8 @@ static void finish_block(ChannelStats *p)
 
     rms = sqrt(2 * p->sum / p->nb_samples);
     peak = p->peak;
-    rms_bin = av_clip(rms * BINS, 0, BINS);
-    peak_bin = av_clip(peak * BINS, 0, BINS);
+    rms_bin = av_clip(lrintf(rms * BINS), 0, BINS);
+    peak_bin = av_clip(lrintf(peak * BINS), 0, BINS);
     p->rms[rms_bin]++;
     p->peaks[peak_bin]++;
 
@@ -158,7 +158,7 @@ static void print_stats(AVFilterContext *ctx)
 
         for (i = BINS, j = 0; i >= 0 && j < 0.2 * p->blknum; i--) {
             if (p->rms[i]) {
-                rmssum += SQR(i / (double)BINS) * p->rms[i];
+                rmssum += SQR(i / (double)BINS);
                 j += p->rms[i];
             }
         }