<div> Hi,   This is my first mail to this group. I have been working on gstreamer since a few days. Read most of the docs and experimented few things like writing new audio sink plugin.   But I am not very much clear about some of the concepts. Can anybody explain me on the following?   <ol style="MARGIN-TOP: 0in" type="1"> <li style="MARGIN: 0in 0in 0pt">Typefind and autoplugging :</li></ol>  I wanted to know how a media player application builds a pipeline by itself, just by the media filename. Does the gstreamer loads all the plugins in the GST_PLUGIN_PATH whenever gstreamer is initialized? If not when will it load the exact plugin required to handle a particular media type. In the docs, it is written that, gstreamer uses a typefind element which iterates through all the plugins which implement typefind functionality. And when a plugin which can handle that media is found, it emits a signal. So does it mean that to load a plugin to handle a particular format, all the plugins in the system needs to be loaded? If not how can the typefind function of a plugin be called without loading it?   Also I read about the elements "playbin" and "decodebin". Do these elements help the application to build the pipeline dynamically? If so what mechanism do they use to build the pipeline?   <ol style="MARGIN-TOP: 0in" type="1" start="2"> <li style="MARGIN: 0in 0in 0pt">XML and Registry in gstreamer:</li></ol> In the docs it is written that XML is used internally to manage the plugin registry. The plugin registry is a file that contains the definition of all the plugins GStreamer knows about to have quick access to the specifics of the plugins.   When is this registry.xml file generated first time? And how is it generated? How is this file used in gstreamer? Is it used for loading plugins dynamically?   Thanks in advance for any sort of help. Regards,</div> <div> Pavan</div>