+
+ OutputAudioFrame const len = audio_length() * output_audio_frame_rate() / content_audio_frame_rate ();
+
+ /* XXX: this depends on whether, alongside this audio, we are running video slower or faster than
+ it should be. The calculation above works out the output audio frames assuming that we are just
+ resampling the audio: it would be incomplete if, for example, we were running this audio alongside
+ 25fps video that was being run at 24fps.
+ */