avfilter/vf_lut2: add timeline support to tlut2 filter

Signed-off-by: Paul B Mahol <onemda@gmail.com>

libavfilter/vf_lut2.c

@@ -401,18 +401,26 @@ static av_cold int init(AVFilterContext *ctx)
 
 static int tlut2_filter_frame(AVFilterLink *inlink, AVFrame *frame)
 {
-    LUT2Context *s = inlink->dst->priv;
-    AVFilterLink *outlink = inlink->dst->outputs[0];
+    AVFilterContext *ctx = inlink->dst;
+    LUT2Context *s = ctx->priv;
+    AVFilterLink *outlink = ctx->outputs[0];
 
     if (s->prev_frame) {
-        AVFrame *out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
-        if (!out) {
-            av_frame_free(&s->prev_frame);
-            s->prev_frame = frame;
-            return AVERROR(ENOMEM);
+        AVFrame *out;
+
+        if (ctx->is_disabled) {
+            out = av_frame_clone(frame);
+        } else {
+            out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+            if (!out) {
+                av_frame_free(&s->prev_frame);
+                s->prev_frame = frame;
+                return AVERROR(ENOMEM);
+            }
+
+            av_frame_copy_props(out, frame);
+            s->lut2(s, out, frame, s->prev_frame);
         }
-        av_frame_copy_props(out, frame);
-        s->lut2(s, out, frame, s->prev_frame);
         av_frame_free(&s->prev_frame);
         s->prev_frame = frame;
         return ff_filter_frame(outlink, out);
@@ -454,6 +462,7 @@ AVFilter ff_vf_tlut2 = {
     .uninit        = uninit,
     .inputs        = tlut2_inputs,
     .outputs       = tlut2_outputs,
+    .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
 };
 
 #endif