diff --git a/ffmpeg.c b/ffmpeg.c
index 0b1b1be..b3977ab 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -1072,6 +1072,8 @@ static void pre_process_video_frame(AVInputStream *ist, AVPicture *picture, void
             buf = NULL;
             picture2 = picture;
         }
+        else
+          dec->coded_frame->interlaced_frame = 0;
     } else {
         picture2 = picture;
     }