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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Audiointerleave is not something that I have seen before but I will give it a try. Thanks for mentioning it.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I will test the synchronization by generating a pure tone sine wave source, tee-ing it into two channels/streams, applying some LADSPA filters to only one of the channels, then mixing them back together with audiomixer (related to audiointerleave). Audiomixer is also supposed to preserve timing like audiointerleave so it is a good proxy. I will choose filters that undo each other (e.g. gain = +6dB follow by gain = -6dB) and I will invert the waveform . During mixing they should cancel each other if the timing is correct. This will be easy to verify by ear by sending the mixed audio to headphones.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><b>From:</b> gstreamer-devel [mailto:gstreamer-devel-bounces@lists.freedesktop.org] <b>On Behalf Of </b>Nicolas Dufresne<br><b>Sent:</b> Monday, December 11, 2017 8:10 PM<br><b>To:</b> Discussion of the development of and with GStreamer <gstreamer-devel@lists.freedesktop.org><br><b>Subject:</b> Re: keeping multiple audio streams synchronized when applying LADSPA filters<o:p></o:p></p><div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>As long as the segment and timestamp are carried (should be handled by the ladspa wrapper plugin) you can later recombine the output with audiointerleave a rewrite of interleave that do proper synchronization. Note that ladspa (same for lv2) wrappers might not cover 100% of the existing filters, I would recommend to tests your filters individually first to make sure they work. If not, ping us again ;-)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div></body></html>