avfilter/af_crossfeed: make options runtime configurable

doc/filters.texi

@@ -3278,6 +3278,10 @@ Set input gain. Default is 0.9.
 Set output gain. Default is 1.
 @end table
 
+@subsection Commands
+
+This filter supports the all above options as @ref{commands}.
+
 @section crystalizer
 Simple algorithm to expand audio dynamic range.
 

libavfilter/af_crossfeed.c

@@ -134,8 +134,20 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in)
     return ff_filter_frame(outlink, out);
 }
 
+static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
+                           char *res, int res_len, int flags)
+{
+    int ret;
+
+    ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags);
+    if (ret < 0)
+        return ret;
+
+    return config_input(ctx->inputs[0]);
+}
+
 #define OFFSET(x) offsetof(CrossfeedContext, x)
-#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
 
 static const AVOption crossfeed_options[] = {
     { "strength",  "set crossfeed strength",  OFFSET(strength),  AV_OPT_TYPE_DOUBLE, {.dbl=.2}, 0, 1, FLAGS },
@@ -175,4 +187,5 @@ AVFilter ff_af_crossfeed = {
     .inputs         = inputs,
     .outputs        = outputs,
     .flags          = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
+    .process_command = process_command,
 };