From dc8e83b4e01cb4e0d3f6fa1d181e0b7d1a89c191 Mon Sep 17 00:00:00 2001
From: Paul B Mahol <onemda@gmail.com>
Date: Fri, 4 Mar 2022 13:33:05 +0100
Subject: [PATCH] avfilter/f_ebur128: make sure frame is writable before
 writing to it

---
 libavfilter/f_ebur128.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libavfilter/f_ebur128.c b/libavfilter/f_ebur128.c
index 35fe9bc6be..1149b2a9cd 100644
--- a/libavfilter/f_ebur128.c
+++ b/libavfilter/f_ebur128.c
@@ -818,6 +818,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
                 y_loudness_lu_graph = lu_to_y(ebur128, loudness_3000 - ebur128->target);
                 y_loudness_lu_gauge = lu_to_y(ebur128, gauge_value);
 
+                av_frame_make_writable(pic);
                 /* draw the graph using the short-term loudness */
                 p = pic->data[0] + ebur128->graph.y*pic->linesize[0] + ebur128->graph.x*3;
                 for (y = 0; y < ebur128->graph.h; y++) {