+ slow_refresh ();
+}
+
+void
+FilmViewer::recreate_butler ()
+{
+ bool const was_running = stop ();
+ _butler.reset ();
+
+ if (!_film) {
+ return;
+ }
+
+ AudioMapping map = AudioMapping (_film->audio_channels(), _audio_channels);
+
+ if (_audio_channels != 2 || _film->audio_channels() < 3) {
+ for (int i = 0; i < min (_film->audio_channels(), _audio_channels); ++i) {
+ map.set (i, i, 1);
+ }
+ } else {
+ /* Special case: stereo output, at least 3 channel input.
+ Map so that Lt = L(-3dB) + Ls(-3dB) + C(-6dB) + Lfe(-10dB)
+ Rt = R(-3dB) + Rs(-3dB) + C(-6dB) + Lfe(-10dB)
+ */
+ map.set (dcp::LEFT, 0, 1 / sqrt(2)); // L -> Lt
+ map.set (dcp::RIGHT, 1, 1 / sqrt(2)); // R -> Rt
+ map.set (dcp::CENTRE, 0, 1 / 2.0); // C -> Lt
+ map.set (dcp::CENTRE, 1, 1 / 2.0); // C -> Rt
+ map.set (dcp::LFE, 0, 1 / sqrt(10)); // Lfe -> Lt
+ map.set (dcp::LFE, 1, 1 / sqrt(10)); // Lfe -> Rt
+ map.set (dcp::LS, 0, 1 / sqrt(2)); // Ls -> Lt
+ map.set (dcp::RS, 1, 1 / sqrt(2)); // Rs -> Rt
+ }
+
+ _butler.reset (new Butler(_player, map, _audio_channels, bind(&PlayerVideo::force, _1, AV_PIX_FMT_RGB24), false, true));
+ if (!Config::instance()->sound() && !_audio.isStreamOpen()) {
+ _butler->disable_audio ();
+ }