lavfi/decimate: switch to an AVOption-based system

doc/filters.texi

@@ -2452,11 +2452,6 @@ The main use of this filter is for very-low-bitrate encoding
 (e.g. streaming over dialup modem), but it could in theory be used for
 fixing movies that were inverse-telecined incorrectly.
 
-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:
-@option{max}:@option{hi}:@option{lo}:@option{frac}.
-
 A description of the accepted options follows.
 
 @table @option

libavfilter/avfilter.c

@@ -664,6 +664,7 @@ int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque
         !strcmp(filter->filter->name,  "crop"      ) ||
         !strcmp(filter->filter->name,  "cropdetect") ||
         !strcmp(filter->filter->name,  "curves"    ) ||
+        !strcmp(filter->filter->name,  "decimate"  ) ||
         !strcmp(filter->filter->name,  "delogo"    ) ||
         !strcmp(filter->filter->name,  "drawbox"   ) ||
         !strcmp(filter->filter->name,  "drawtext"  ) ||

libavfilter/vf_decimate.c

@@ -244,8 +244,6 @@ static const AVFilterPad decimate_outputs[] = {
     { NULL }
 };
 
-static const char *const shorthand[] = { "max", "hi", "lo", "frac", NULL };
-
 AVFilter avfilter_vf_decimate = {
     .name        = "decimate",
     .description = NULL_IF_CONFIG_SMALL("Remove near-duplicate frames."),
@@ -257,5 +255,4 @@ AVFilter avfilter_vf_decimate = {
     .inputs        = decimate_inputs,
     .outputs       = decimate_outputs,
     .priv_class    = &decimate_class,
-    .shorthand     = shorthand,
 };