OGG file playback: fails on OSX 10.11.6, works on Ubuntu 16.04 LTS?

schneesonne

Hi,

my problem is that OpenSesame 3.1.4 doesn't play my OGG sound stimuli on OSX 10.11.6. The experiment runs as it should, but instead of playing the sound, I only hear a crack whenever a new sound file should be played.

When opening the same experiment with the same OGG files in OpenSesame 3.1.4b1 on Ubuntu 16.04 LTS the sound playback works fine. Stand-alone playback of the OGG files on OSX with any audio player also works well.

Thanks for any hints on solving the playback issue on OSX 10.11.6.

Nikolay

Jarik

Hi Nikolay,

Converting to .wav might work.

Best,
Jarik

sebastiaan

I understood that there's a general problem with sound playback on (some) Mac OS systems. (Right @Daniel?) So it's probably not specific to the file format.

If converting to .wav doesn't resolve the issue, then you could consider using pyaudio, which is a different library for sound playback. If you search this forum, you'll find plenty of examples, and you can also find some examples on their own site:

• https://people.csail.mit.edu/hubert/pyaudio/

Cheers!
Sebastiaan

Daniel

Hi guys,

Yes, audio playback is a disaster on mac, and this is all due to the pygame libraries being a mess; especially since the update to MacOS Sierra lately.

I somehow managed to get sound to work for media_player_mpy by addressing the pygame.mixer library myself (which opensesame uses for audio playback), but if I try using the sampler/synth items, I only hear a popping noise. I don't see anything wrong with how these items use pygame.mixer at first sight, so I have no clue why it is being so difficult.

I don't think pygame will improve or get fixed in this regard, so our best bet would be to find another library to replace it with. The python-mediadecoder library behind media_player_mpy should also be able to decode stand-alone audio files (since it uses ffmpeg), but I haven't gotten around extending it to do so.

All in all, I think it will be a while before we have this problem solved...