https://bugs.gentoo.org/961982
--- a/src/codec.cpp
+++ b/src/codec.cpp
@@ -450,3 +450,3 @@
 
-		self->was_keyframe_ = frame->key_frame;
+		self->was_keyframe_ = (frame->flags & AV_FRAME_FLAG_KEY);
 		self->was_bad_ = !got_frame;