From b3b268a9a9e9dff993813103bc759f9274dfa729 Mon Sep 17 00:00:00 2001 From: Martin Vignali Date: Fri, 30 Mar 2018 22:36:01 +0200 Subject: [PATCH 6/7] avfilter/showvolume : use some kind of log scale for display --- libavfilter/avf_showvolume.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/libavfilter/avf_showvolume.c b/libavfilter/avf_showvolume.c index d97e5de3af..06e3b46b0e 100644 --- a/libavfilter/avf_showvolume.c +++ b/libavfilter/avf_showvolume.c @@ -251,7 +251,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples) AVFilterLink *outlink = ctx->outputs[0]; ShowVolumeContext *s = ctx->priv; const int step = s->step; - int c, i, j, k; + int c, i, j, k, max_draw; AVFrame *out; if (!s->out || s->out->width != outlink->w || @@ -297,8 +297,9 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples) s->values[c * VAR_VARS_NB + VAR_VOLUME] = 20.0 * log10(max); max = av_clipf(max, 0, 1); + max_draw = -1 * (outlink->h * log10(max) * 0.5); - for (j = outlink->h - outlink->h * max; j < s->w; j++) { + for (j = max_draw; j < s->w; j++) { uint8_t *dst = s->out->data[0] + j * s->out->linesize[0] + c * (s->b + s->h) * 4; for (k = 0; k < s->h; k++) { AV_WN32A(&dst[k * 4], lut[s->w - j - 1]); @@ -325,11 +326,12 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples) s->values[c * VAR_VARS_NB + VAR_VOLUME] = 20.0 * log10(max); max = av_clipf(max, 0, 1); + max_draw = s->w + (log10(max) * 0.5 * s->w); for (j = 0; j < s->h; j++) { uint8_t *dst = s->out->data[0] + (c * s->h + c * s->b + j) * s->out->linesize[0]; - for (k = 0; k < s->w * max; k++) { + for (k = 0; k < max_draw; k++) { AV_WN32A(dst + k * 4, lut[k]); if (k & step) k += step; -- 2.14.3 (Apple Git-98)