diff --git a/libavformat/segafilm.c b/libavformat/segafilm.c
index 4c6b68426c..800f8e7287 100644
--- a/libavformat/segafilm.c
+++ b/libavformat/segafilm.c
@@ -233,6 +233,7 @@ static int film_read_header(AVFormatContext *s)
             else if (film->audio_type != AV_CODEC_ID_NONE)
                 audio_frame_counter += (film->sample_table[i].sample_size /
                     (film->audio_channels * film->audio_bits / 8));
+            film->sample_table[i].keyframe = 1;
         } else {
             film->sample_table[i].stream = film->video_stream_index;
             film->sample_table[i].pts = AV_RB32(&scratch[8]) & 0x7FFFFFFF;