lavfi/showspectrum: add priv_class and flags to options

libavfilter/avf_showspectrum.c

@@ -47,10 +47,11 @@ typedef struct {
 } ShowSpectrumContext;
 
 #define OFFSET(x) offsetof(ShowSpectrumContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 
 static const AVOption showspectrum_options[] = {
-    { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "640x480"}, 0, 0 },
-    { "s",    "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "640x480"}, 0, 0 },
+    { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "640x480"}, 0, 0, FLAGS },
+    { "s",    "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "640x480"}, 0, 0, FLAGS },
     { NULL },
 };
 
@@ -311,4 +312,6 @@ AVFilter avfilter_avf_showspectrum = {
         },
         { .name = NULL }
     },
+
+    .priv_class = &showspectrum_class,
 };