Hello folks, with my first post on this ML I'm glad to announce a new plugin called span. I have written a plugin that can receive PCM-data from other plugins (e.g. mp3ng) to compute frequency-data and to provide them to other plugins to display a 'Sp'ectrum 'An'alyzer. It is meant as a kind of middleware between these providers and clients to be as generic as needed to be able to implement the visualisation on all kinds of output-devices (OSD, lcd, graphlcd, framebuffer, etc.). It is available at http://lcr.vdr-developer.org/ There's a thread also at http://www.vdr-portal.de/board/thread.php?postid=513343#post513343 providing the latest information. @Klaus: Is there an obstacle to get all plugins that support some kind of service? s.th like static cPlugin **CallAllServicePlugins(const char *Id, void *Data = NULL); that returns a list of all plugins supporting the requested service. I would like to use it to collect the names of all data-providers and all visualization-clients. Kindly yours Christian Leuschen Abstract from the plugins's README: This is a 'Sp'ectrum 'An'alyzer Plugin for the Video Disk Recorder (VDR). Requirements: VDR & (lib)fftw3 Description: A plugin that can receive PCM-data from other plugins (e.g. mp3ng) to compute frequency-data and to provide them to other plugins to display a 'Sp'ectrum 'An'alyzer. It is meant as a kind of middleware between these providers and clients to be as generic as needed to be able to implement the visualisation on all kinds of output-devices (OSD, lcd, graphlcd, framebuffer, etc.). Sketch of the architecture: | Data-provider sends PCM-data ---> | SpAn-plugin | >--- Visualization-clients request the spectrum-data "making s.th. handsome out of it" | Installation: cd /put/your/path/here/VDR/PLUGINS/src tar -xzf /put/your/path/here/vdr-span-X.Y.Z.tar.bz2 ln -s span-X.Y.Z span cd /put/your/path/here/VDR make make plugins ./vdr -P span Setup: Activate spectrum analyzer? yes/no De-(Activates) the plugin. yes: The plugin receives data (only if clients also request data) and on request hands the results over to clients. no: In this case all data provider- and visualization-plugins are rejected when trying to hand over data or to request results. Use logarithmic diagram yes/no A (yet naive) try to equalize the heights of the bars a bit. Lower frequencies are prevailing which results in an "high dynamic range of the heights of the bars" (= mostly few extremely high bars on the left, further right more decreasing or even no bars at all). yes: Suspends a "no" at "Use pure (unequalized) data". Scaling of the heights of the bars is done logarithmically. no: No logarithmic scaling is done. Tips to improve this way of equalizing are warmly welcome! Hide mainmenu entry yes/no Should be self-explanatory. At the moment there is no use of displaying the plugin's entry in the main menu. See ToDo (way below) for the reason. Use pure (unequalized) data yes/no yes: Really compute the pure data without equalizing anyhow. no: Values of higher frequencies are emphasized resulting in a "bit nicer way of displaying the frequencies" than with pure data. Notes: - Tested on VDR-1.4.0 with a FF-DVB-s 2MB (CPU = PIII 1,2GHz) with mp3ng-plugin as self-made data provider as well as visualization-client. Additionally the lcdproc-plugin was used as visualization-client, but just as a proof-of-concept. Thus, there were two clients active simultaneously. - I would be very glad if the authors of plugins for rendering vdr-information on (external) displays (graphlcd/graphtft/lcdproc/etc.) or the OSD (mp3(ng)/ cdda/radio?/muggle?) used the data provided by this plugin to visualize a spectrum analyzer. Generic example how to use it: // Please see the "real" README for the "HowTo". TODO: - Test the stuff with cdda-plugin (provider) and graphlcd-plugin (visualization) - Test it on my streaming-client (it's a PIII 450MHz with DXR3 now) - Implement the output of the names of all data-source- and visualization-plugins on selecting the mainmenu's entry. A change in the "Plugin-Service-Protocol" could be neccessary to support getting ALL plugins that can handle a service. - Implement bar-peaks and their fall off
