Browse Source

avfilter/vf_zscale: add support for setting scaling filter parameters

param_a/b are utilized for this.
tags/n4.4
Jan Ekström 4 years ago
parent
commit
58e59396f5
2 changed files with 14 additions and 0 deletions
  1. +7
    -0
      doc/filters.texi
  2. +7
    -0
      libavfilter/vf_zscale.c

+ 7
- 0
doc/filters.texi View File

@@ -22393,6 +22393,13 @@ Possible values are:

@item npl
Set the nominal peak luminance.

@item param_a
Parameter A for scaling filters. Parameter "b" for bicubic, and the number of
filter taps for lanczos.

@item param_b
Parameter B for scaling filters. Parameter "c" for bicubic.
@end table

The values of the @option{w} and @option{h} options are expressions


+ 7
- 0
libavfilter/vf_zscale.c View File

@@ -101,6 +101,8 @@ typedef struct ZScaleContext {
char *size_str;
double nominal_peak_luminance;
int approximate_gamma;
double param_a;
double param_b;

char *w_expr; ///< width expression string
char *h_expr; ///< height expression string
@@ -601,6 +603,8 @@ static int filter_frame(AVFilterLink *link, AVFrame *in)
s->params.resample_filter_uv = s->filter;
s->params.nominal_peak_luminance = s->nominal_peak_luminance;
s->params.allow_approximate_gamma = s->approximate_gamma;
s->params.filter_param_a = s->params.filter_param_a_uv = s->param_a;
s->params.filter_param_b = s->params.filter_param_b_uv = s->param_b;

format_init(&s->src_format, in, desc, s->colorspace_in,
s->primaries_in, s->trc_in, s->range_in, s->chromal_in);
@@ -897,6 +901,9 @@ static const AVOption zscale_options[] = {
{ "cin", "set input chroma location", OFFSET(chromal_in), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_CHROMA_BOTTOM, FLAGS, "chroma" },
{ "npl", "set nominal peak luminance", OFFSET(nominal_peak_luminance), AV_OPT_TYPE_DOUBLE, {.dbl = NAN}, 0, DBL_MAX, FLAGS },
{ "agamma", "allow approximate gamma", OFFSET(approximate_gamma), AV_OPT_TYPE_BOOL, {.i64 = 1}, 0, 1, FLAGS },
{ "param_a", "parameter A, which is parameter \"b\" for bicubic, "
"and the number of filter taps for lanczos", OFFSET(param_a), AV_OPT_TYPE_DOUBLE, {.dbl = NAN}, -DBL_MAX, DBL_MAX, FLAGS },
{ "param_b", "parameter B, which is parameter \"c\" for bicubic", OFFSET(param_b), AV_OPT_TYPE_DOUBLE, {.dbl = NAN}, -DBL_MAX, DBL_MAX, FLAGS },
{ NULL }
};



Loading…
Cancel
Save