avfilter/vf_lut3d: allow to control when to upload CLUT for haldclut

doc/filters.texi

@@ -13793,6 +13793,10 @@ The Hald CLUT input can be a simple picture or a complete video stream.
 The filter accepts the following options:
 
 @table @option
+@item clut
+Set which CLUT video frames will be processed from second input stream,
+can be @var{first} or @var{all}. Default is @var{all}.
+
 @item shortest
 Force termination when the shortest input terminates. Default is @code{0}.
 @item repeatlast

libavfilter/lut3d.h

@@ -66,6 +66,8 @@ typedef struct LUT3DContext {
     avfilter_action_func *interp;
     Lut3DPreLut prelut;
 #if CONFIG_HALDCLUT_FILTER
+    int clut;
+    int got_clut;
     uint8_t clut_rgba_map[4];
     int clut_step;
     int clut_bits;

libavfilter/vf_lut3d.c

@@ -1217,6 +1217,11 @@ static int process_command(AVFilterContext *ctx, const char *cmd, const char *ar
 static const AVOption lut3d_haldclut_options[] = {
 #if CONFIG_LUT3D_FILTER
     { "file", "set 3D LUT file name", OFFSET(file), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
+#endif
+#if CONFIG_HALDCLUT_FILTER
+    { "clut", "when to process CLUT", OFFSET(clut), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, .flags = TFLAGS, "clut" },
+    {   "first", "process only first CLUT, ignore rest", 0, AV_OPT_TYPE_CONST, {.i64=0}, .flags = TFLAGS, "clut" },
+    {   "all",   "process all CLUTs",                    0, AV_OPT_TYPE_CONST, {.i64=1}, .flags = TFLAGS, "clut" },
 #endif
     COMMON_OPTIONS
 };
@@ -1519,12 +1524,15 @@ static int update_apply_clut(FFFrameSync *fs)
         return ret;
     if (!second)
         return ff_filter_frame(ctx->outputs[0], master);
-    if (lut3d->clut_float)
-        update_clut_float(ctx->priv, second);
-    else if (lut3d->clut_planar)
-        update_clut_planar(ctx->priv, second);
-    else
-        update_clut_packed(ctx->priv, second);
+    if (lut3d->clut || !lut3d->got_clut) {
+        if (lut3d->clut_float)
+            update_clut_float(ctx->priv, second);
+        else if (lut3d->clut_planar)
+            update_clut_planar(ctx->priv, second);
+        else
+            update_clut_packed(ctx->priv, second);
+        lut3d->got_clut = 1;
+    }
     out = apply_lut(inlink, master);
     return ff_filter_frame(ctx->outputs[0], out);
 }