<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div><br></div><blockquote type="cite"><div><br></div></blockquote><blockquote type="cite"><div><div dir="ltr">Dear all,<div><br></div><div>We are involved in a project with an embedded system based on SGTL5000 audio chip.</div><div>So following modules are involved:</div><div>- SGTL5000 driver</div><div>- Kernel: alsa</div><div>- Alsa-lib</div><div>- GStreamer</div><div>- Qt app</div><div><br></div><div>We had some problems to manage the audio card (SGTL5000) from GStreamer+alsamixer (amixer). For that reason me need to understand GStreamer source code in more detail.</div><div><br></div><div>Basically, we see that:</div><div>- SGTL5000 can be configured by I2C protocol messages to set active input (Line in OR Mic OR I2S_IN), internal audio switch and output (Line out)</div><div>- GStreamer "takes" audio input by alsasrc and "puts" audio output by alsasink</div><div>- How both match, meaning where does GStreamer "take" and "put" audio samples?</div><div>- ISSUE When audio comes from Line in and goes to Line out, volume element does nothing</div><div>(as if audio just flows from SGTL5000 line in to SGTL5000 line out WITHOUT being processed by GStreamer (software) volume element</div><div><br></div><div>(Hope I explained right)</div><div><br></div><div>QUESTION: Is there any document describing the platform (high level description) other than:</div><div>- Class description in <a href="http://www.freedesktop.org/software/gstreamer-sdk/data/docs/2012.5/gstreamer-0.10/">http://www.freedesktop.org/software/gstreamer-sdk/data/docs/2012.5/gstreamer-0.10/</a></div><div>- GStreamer Application Development Manual (0.10.36)</div><div><br></div><div><br></div><div>Regards,</div><div><br></div><div>Carlos de Paz</div><div><br></div></div> </div></blockquote></body></html>