| Message ID | 20180512202435.6479-2-onemda@gmail.com |
|---|---|
| State | New |
| Headers | show |
On Sat, May 12, 2018 at 10:24:35PM +0200, Paul B Mahol wrote: > For better control of denoising. > > Signed-off-by: Paul B Mahol <onemda@gmail.com> > --- > doc/filters.texi | 4 ++++ > libavfilter/vf_nlmeans.c | 5 ++++- > 2 files changed, 8 insertions(+), 1 deletion(-) > > diff --git a/doc/filters.texi b/doc/filters.texi > index d77c67eb10..60ce18298b 100644 > --- a/doc/filters.texi > +++ b/doc/filters.texi > @@ -11420,6 +11420,10 @@ Set research size. > Same as @option{r} but for chroma planes. > > The default value is @var{0} and means automatic. > + > +@item a > +Set denoising amount. Lower values reduces blurring. > +Default value is @var{1.0} and means full denoising. I'm not so fond of adding another semantically identical option to "strength". Do you have some literature on such an option?
On 5/18/18, Clement Boesch <u@pkh.me> wrote: > On Sat, May 12, 2018 at 10:24:35PM +0200, Paul B Mahol wrote: >> For better control of denoising. >> >> Signed-off-by: Paul B Mahol <onemda@gmail.com> >> --- >> doc/filters.texi | 4 ++++ >> libavfilter/vf_nlmeans.c | 5 ++++- >> 2 files changed, 8 insertions(+), 1 deletion(-) >> >> diff --git a/doc/filters.texi b/doc/filters.texi >> index d77c67eb10..60ce18298b 100644 >> --- a/doc/filters.texi >> +++ b/doc/filters.texi >> @@ -11420,6 +11420,10 @@ Set research size. >> Same as @option{r} but for chroma planes. >> >> The default value is @var{0} and means automatic. >> + >> +@item a >> +Set denoising amount. Lower values reduces blurring. >> +Default value is @var{1.0} and means full denoising. > > I'm not so fond of adding another semantically identical option to > "strength". Do you have some literature on such an option? It is not identical, you need certain math skills to get it.
diff --git a/doc/filters.texi b/doc/filters.texi index d77c67eb10..60ce18298b 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -11420,6 +11420,10 @@ Set research size. Same as @option{r} but for chroma planes. The default value is @var{0} and means automatic. + +@item a +Set denoising amount. Lower values reduces blurring. +Default value is @var{1.0} and means full denoising. @end table @section nnedi diff --git a/libavfilter/vf_nlmeans.c b/libavfilter/vf_nlmeans.c index 6c9c9d312d..ac6380bb83 100644 --- a/libavfilter/vf_nlmeans.c +++ b/libavfilter/vf_nlmeans.c @@ -53,6 +53,7 @@ typedef struct NLMeansContext { int chroma_w, chroma_h; double pdiff_scale; // invert of the filtering parameter (sigma*10) squared double sigma; // denoising strength + double amount; // denoising amount int patch_size, patch_hsize; // patch size and half size int patch_size_uv, patch_hsize_uv; // patch size and half size for chroma planes int research_size, research_hsize; // research size and half size @@ -77,6 +78,7 @@ static const AVOption nlmeans_options[] = { { "pc", "patch size for chroma planes", OFFSET(patch_size_uv), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 99, FLAGS }, { "r", "research window", OFFSET(research_size), AV_OPT_TYPE_INT, { .i64 = 7*2+1 }, 0, 99, FLAGS }, { "rc", "research window for chroma planes", OFFSET(research_size_uv), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 99, FLAGS }, + { "a", "denoising amount", OFFSET(amount), AV_OPT_TYPE_DOUBLE, { .dbl = 1.0 }, 0.001, 1.0, FLAGS }, { NULL } }; @@ -528,13 +530,14 @@ static av_cold int init(AVFilterContext *ctx) int i; NLMeansContext *s = ctx->priv; const double h = s->sigma * 10.; + const double a = 1. / (s->amount * s->amount); s->pdiff_scale = 1. / (h * h); s->max_meaningful_diff = -log(1/255.) / s->pdiff_scale; s->pdiff_lut_scale = 1./s->max_meaningful_diff * WEIGHT_LUT_SIZE; av_assert0((s->max_meaningful_diff - 1) * s->pdiff_lut_scale < FF_ARRAY_ELEMS(s->weight_lut)); for (i = 0; i < WEIGHT_LUT_SIZE; i++) - s->weight_lut[i] = exp(-i / s->pdiff_lut_scale * s->pdiff_scale); + s->weight_lut[i] = exp((-i / s->pdiff_lut_scale * s->pdiff_scale) * a); CHECK_ODD_FIELD(research_size, "Luma research window"); CHECK_ODD_FIELD(patch_size, "Luma patch");
For better control of denoising. Signed-off-by: Paul B Mahol <onemda@gmail.com> --- doc/filters.texi | 4 ++++ libavfilter/vf_nlmeans.c | 5 ++++- 2 files changed, 8 insertions(+), 1 deletion(-)