+ if (_film->audio_channels() == 0 && _film->minimum_audio_channels() > 0) {
+ /* Put audio in where there is none at all */
+ int64_t af = video_frames_to_audio_frames (_video_frames_out, 48000, _film->dcp_frame_rate ());
+ while (af) {
+ int64_t const this_time = min (af, 24000L);
+ shared_ptr<AudioBuffers> out (new AudioBuffers (_film->minimum_audio_channels(), this_time));
+ out->make_silent ();
+ out->set_frames (this_time);
+ write_audio (out);
+
+ af -= this_time;
+ }
+ }
+