[FFmpeg-devel] [PATCH] lavfi/boxblur: add support to named options

Stefano Sabatini stefasab at gmail.com
Fri Feb 22 20:02:44 CET 2013


On date Thursday 2013-02-21 21:04:26 +0100, Clément Bœsch encoded:
> On Wed, Feb 20, 2013 at 03:45:32PM +0100, Stefano Sabatini wrote:
> > TODO: bump micro
> > ---
> >  doc/filters.texi         |   50 +++++++++++++++++++----------
> >  libavfilter/vf_boxblur.c |   80 +++++++++++++++++++++++++++++++---------------
> >  2 files changed, 88 insertions(+), 42 deletions(-)
> > 
> > diff --git a/doc/filters.texi b/doc/filters.texi
> > index 3be8363..2a03d69 100644
> > --- a/doc/filters.texi
> > +++ b/doc/filters.texi
> > @@ -1782,17 +1782,30 @@ considered black, and defaults to 32.
> >  
> >  Apply boxblur algorithm to the input video.
> >  
> > -This filter accepts the parameters:
> > - at var{luma_radius}:@var{luma_power}:@var{chroma_radius}:@var{chroma_power}:@var{alpha_radius}:@var{alpha_power}
> > +The filter accepts parameters as a list of @var{key}=@var{value}
> > +pairs, separated by ":". If the key of the first options is omitted,
> > +the arguments are interpreted according to the syntax
> > + at option{luma_radius}:@option{luma_power}:@option{chroma_radius}:@option{chroma_power}:@option{alpha_radius}:@option{alpha_power}.
> >  
> > -Chroma and alpha parameters are optional, if not specified they default
> > -to the corresponding values set for @var{luma_radius} and
> > - at var{luma_power}.
> > +A description of the accepted parameters follows.
> >  
> > - at var{luma_radius}, @var{chroma_radius}, and @var{alpha_radius} represent
> > -the radius in pixels of the box used for blurring the corresponding
> > -input plane. They are expressions, and can contain the following
> > -constants:
> > + at table @option
> > + at item luma_radius, lr
> > + at item chroma_radius, cr
> > + at item alpha_radius, ar
> > +Set an expression for the box radius in pixels used for blurring the
> > +corresponding input plane.
> > +
> > +The radius value must be a non-negative number, and must not be
> > +greater than the value of the expression @code{min(w,h)/2} for the
> > +luma and alpha planes, and of @code{min(cw,ch)/2} for the chroma
> > +planes.
> > +
> > +Default value for @option{luma_radius} is "2".  If not specified,
> > + at option{chroma_radius} and @option{alpha_radius} default to the
> > +corresponding value set for @option{luma_radius}.
> > +
> > +The expressions can contain the following constants:
> >  @table @option
> >  @item w, h
> >  the input width and height in pixels
> > @@ -1805,13 +1818,18 @@ horizontal and vertical chroma subsample values. For example for the
> >  pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
> >  @end table
> >  
> > -The radius must be a non-negative number, and must not be greater than
> > -the value of the expression @code{min(w,h)/2} for the luma and alpha planes,
> > -and of @code{min(cw,ch)/2} for the chroma planes.
> > + at item luma_power, lp
> > + at item chroma_power, cp
> > + at item alpha_power, ap
> > +Specify how many times the boxblur filter is applied to the
> > +corresponding plane.
> >  
> > - at var{luma_power}, @var{chroma_power}, and @var{alpha_power} represent
> > -how many times the boxblur filter is applied to the corresponding
> > -plane.
> > +Default value for @option{luma_power} is 2.  If not specified,
> > + at option{chroma_power} and @option{alpha_power} default to the
> > +corresponding value set for @option{luma_power}.
> > +
> > +A value of 0 will disable the effect.
> > + at end table
> >  
> >  Some examples follow:
> >  
> > @@ -1827,7 +1845,7 @@ boxblur=2:1
> >  @item
> >  Set luma radius to 2, alpha and chroma radius to 0
> >  @example
> > -boxblur=2:1:0:0:0:0
> > +boxblur=2:1:cr=0:ar=0
> >  @end example
> >  
> >  @item
> > diff --git a/libavfilter/vf_boxblur.c b/libavfilter/vf_boxblur.c
> > index 9ee3ea5..4ba4157 100644
> > --- a/libavfilter/vf_boxblur.c
> > +++ b/libavfilter/vf_boxblur.c
> > @@ -28,6 +28,7 @@
> >  #include "libavutil/avstring.h"
> >  #include "libavutil/common.h"
> >  #include "libavutil/eval.h"
> > +#include "libavutil/opt.h"
> >  #include "libavutil/pixdesc.h"
> >  #include "avfilter.h"
> >  #include "formats.h"
> > @@ -57,15 +58,14 @@ enum var_name {
> >  typedef struct {
> >      int radius;
> >      int power;
> > +    char *radius_expr;
> >  } FilterParam;
> >  
> >  typedef struct {
> > +    const AVClass *class;
> >      FilterParam luma_param;
> >      FilterParam chroma_param;
> >      FilterParam alpha_param;
> > -    char luma_radius_expr  [256];
> > -    char chroma_radius_expr[256];
> > -    char alpha_radius_expr [256];
> >  
> >      int hsub, vsub;
> >      int radius[4];
> > @@ -73,6 +73,30 @@ typedef struct {
> >      uint8_t *temp[2]; ///< temporary buffer used in blur_power()
> >  } BoxBlurContext;
> >  
> > +#define OFFSET(x) offsetof(BoxBlurContext, x)
> > +#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
> > +
> > +static const AVOption boxblur_options[] = {
> > +    { "luma_radius", "set luma radius", OFFSET(luma_param.radius_expr), AV_OPT_TYPE_STRING, {.str="2"}, .flags = FLAGS },
> > +    { "lr",          "set luma radius", OFFSET(luma_param.radius_expr), AV_OPT_TYPE_STRING, {.str="2"}, .flags = FLAGS },
> > +    { "luma_power",  "set luma power",  OFFSET(luma_param.power), AV_OPT_TYPE_INT, {.i64=2}, 0, INT_MAX, .flags = FLAGS },
> > +    { "lp",          "set luma power",  OFFSET(luma_param.power), AV_OPT_TYPE_INT, {.i64=2}, 0, INT_MAX, .flags = FLAGS },
> > +
> > +    { "chroma_radius", "set chroma radius", OFFSET(chroma_param.radius_expr), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
> > +    { "cr",            "set chroma radius", OFFSET(chroma_param.radius_expr), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
> > +    { "chroma_power",  "set chroma power",  OFFSET(chroma_param.power), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, .flags = FLAGS },
> > +    { "cp",            "set chroma power",  OFFSET(chroma_param.power), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, .flags = FLAGS },
> > +
> > +    { "alpha_radius", "set alpha radius", OFFSET(alpha_param.radius_expr), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
> > +    { "ar",           "set alpha radius", OFFSET(alpha_param.radius_expr), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
> > +    { "alpha_power",  "set alpha power",  OFFSET(alpha_param.power), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, .flags = FLAGS },
> > +    { "ap",           "set alpha power",  OFFSET(alpha_param.power), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, .flags = FLAGS },
> > +
> > +    { NULL }
> > +};
> > +
> > +AVFILTER_DEFINE_CLASS(boxblur);
> > +
> >  #define Y 0
> >  #define U 1
> >  #define V 2
> > @@ -81,35 +105,36 @@ typedef struct {
> >  static av_cold int init(AVFilterContext *ctx, const char *args)
> >  {
> >      BoxBlurContext *boxblur = ctx->priv;
> > -    int e;
> > +    static const char *shorthand[] = {
> > +        "luma_radius",   "luma_power",
> > +        "chroma_radius", "chroma_power",
> > +        "alpha_radius",  "alpha_power",
> > +        NULL
> > +    };
> > +    int ret;
> >  
> > -    if (!args) {
> > -        av_log(ctx, AV_LOG_ERROR,
> > -               "Filter expects 2 or 4 or 6 arguments, none provided\n");
> > -        return AVERROR(EINVAL);
> > -    }
> > +    boxblur->class = &boxblur_class;
> > +    av_opt_set_defaults(boxblur);
> >  
> > -    e = sscanf(args, "%255[^:]:%d:%255[^:]:%d:%255[^:]:%d",
> > -               boxblur->luma_radius_expr,   &boxblur->luma_param  .power,
> > -               boxblur->chroma_radius_expr, &boxblur->chroma_param.power,
> > -               boxblur->alpha_radius_expr,  &boxblur->alpha_param .power);
> > +    if ((ret = av_opt_set_from_string(boxblur, args, shorthand, "=", ":")) < 0)
> > +        return ret;
> >  
> > -    if (e != 2 && e != 4 && e != 6) {
> > -        av_log(ctx, AV_LOG_ERROR,
> > -               "Filter expects 2 or 4 or 6 params, provided %d\n", e);
> > -        return AVERROR(EINVAL);
> > +    /* fill missing params */
> > +    if (!boxblur->chroma_param.radius_expr) {
> > +        boxblur->chroma_param.radius_expr = strdup(boxblur->luma_param.radius_expr);
> 
> av_strdup()

Fixed.

> 
> > +        if (!boxblur->chroma_param.radius_expr)
> > +            return AVERROR(ENOMEM);
> >      }
> > -
> > -    if (e < 4) {
> > +    if (boxblur->chroma_param.power < 0)
> >          boxblur->chroma_param.power = boxblur->luma_param.power;
> > -        av_strlcpy(boxblur->chroma_radius_expr, boxblur->luma_radius_expr,
> > -                   sizeof(boxblur->chroma_radius_expr));
> > +
> > +    if (!boxblur->alpha_param.radius_expr) {
> > +        boxblur->alpha_param.radius_expr = strdup(boxblur->luma_param.radius_expr);
> 
> ditto
> 
> Note: is the expression freed in this case? I'm asking because an
> av_free() would have fail.

Fixed.

[...] 
> LGTM if tested otherwise

Applied, thanks.
-- 
FFmpeg = Fancy & Fierce Majestic Ponderous Ermetic Game


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