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40 lines
1.3 KiB
Text
40 lines
1.3 KiB
Text
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level plugin by thomas <thomas@apestaart.org>
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this plugin signals:
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- running time since last EOS/start
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- channel
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- RMS level
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- peak level
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- decaying peak level
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over the given interval.
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This is useful for a VU meter display and for plotting out the signal graph.
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The VU meter can either display RMS, or display immediate peak level and
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have the falloff decaying peak level displayed as a line.
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The interval for signal emission, ttl of decay peak, and falloff of decay peak
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can all be set.
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The element only takes unsigned data in; it could be extended to signed as
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well, if separate fast chain functions are made that displaces the incoming
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data to its midpoint (ie, 0,65535 should be mapped to -32768, 32767)
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There are two demo apps, apps and plot. apps will create some GTK sliders
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to display the volume. plot will output data readable by gnuplot.
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Here is a sample plot script to plot output of the plot command that was
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stored to plot.dat
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set xlabel "Seconds"
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set ylabel "dB"
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set yrange [-60:0]
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plot 'plot.dat' using 1:2 title 'L RMS' with lines, \
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'plot.dat' using 1:3 title 'L peak' with lines, \
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'plot.dat' using 1:4 title 'L decay' with lines
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plot 'plot.dat' using 1:5 title 'R RMS' with lines, \
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'plot.dat' using 1:6 title 'R peak' with lines, \
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'plot.dat' using 1:7 title 'R decay' with lines
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