fftools/ffmpeg: use a mutex for enc_stats_write()

It may be called concurrently from different threads to write into the
same file.

1 files changed, 4 insertions, 0 deletions

diff --git a/fftools/ffmpeg_enc.c b/fftools/ffmpeg_enc.c
index d774a7e008..57590a43a3 100644
--- a/fftools/ffmpeg_enc.c
+++ b/fftools/ffmpeg_enc.c
@@ -491,6 +491,8 @@ void enc_stats_write(OutputStream *ost, EncStats *es,
         ptsi = fd->dec.pts;
     }
 
+    pthread_mutex_lock(&es->lock);
+
     for (size_t i = 0; i < es->nb_components; i++) {
         const EncStatsComponent *c = &es->components[i];
 
@@ -538,6 +540,8 @@ void enc_stats_write(OutputStream *ost, EncStats *es,
     }
     avio_w8(io, '\n');
     avio_flush(io);
+
+    pthread_mutex_unlock(&es->lock);
 }
 
 static inline double psnr(double d)