lavfi/vsrc: switch to ff_filter_frame.

libavfilter/vsrc_cellauto.c

@@ -319,11 +319,7 @@ static int request_frame(AVFilterLink *outlink)
 #ifdef DEBUG
     show_cellauto_row(outlink->src);
 #endif
-
-    ff_start_frame(outlink, avfilter_ref_buffer(picref, ~0));
-    ff_draw_slice(outlink, 0, cellauto->h, 1);
-    ff_end_frame(outlink);
-    avfilter_unref_buffer(picref);
+    ff_filter_frame(outlink, picref);
 
     return 0;
 }

libavfilter/vsrc_life.c

@@ -439,11 +439,7 @@ static int request_frame(AVFilterLink *outlink)
 #ifdef DEBUG
     show_life_grid(outlink->src);
 #endif
-
-    ff_start_frame(outlink, avfilter_ref_buffer(picref, ~0));
-    ff_draw_slice(outlink, 0, life->h, 1);
-    ff_end_frame(outlink);
-    avfilter_unref_buffer(picref);
+    ff_filter_frame(outlink, picref);
 
     return 0;
 }

libavfilter/vsrc_mptestsrc.c

@@ -355,11 +355,7 @@ static int request_frame(AVFilterLink *outlink)
     }
 
     test->frame_nb++;
-
-    ff_start_frame(outlink, avfilter_ref_buffer(picref, ~0));
-    ff_draw_slice(outlink, 0, picref->video->h, 1);
-    ff_end_frame(outlink);
-    avfilter_unref_buffer(picref);
+    ff_filter_frame(outlink, picref);
 
     return 0;
 }