mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-11-24 10:41:04 +00:00
40 lines
1.3 KiB
Text
40 lines
1.3 KiB
Text
|
level plugin by thomas <thomas@apestaart.org>
|
||
|
|
|
||
|
|
this plugin signals:
|
||
|
|
- running time since last EOS/start
|
||
|
|
- channel
|
||
|
|
- RMS level
|
||
|
|
- peak level
|
||
|
|
- decaying peak level
|
||
|
|
over the given interval.
|
||
|
|
|
||
|
|
This is useful for a VU meter display and for plotting out the signal graph.
|
||
|
|
The VU meter can either display RMS, or display immediate peak level and
|
||
|
|
have the falloff decaying peak level displayed as a line.
|
||
|
|
|
||
|
|
The interval for signal emission, ttl of decay peak, and falloff of decay peak
|
||
|
|
can all be set.
|
||
|
|
|
||
|
|
The element only takes unsigned data in; it could be extended to signed as
|
||
|
|
well, if separate fast chain functions are made that displaces the incoming
|
||
|
|
data to its midpoint (ie, 0,65535 should be mapped to -32768, 32767)
|
||
|
|
|
||
|
|
There are two demo apps, apps and plot. apps will create some GTK sliders
|
||
|
|
to display the volume. plot will output data readable by gnuplot.
|
||
|
|
|
||
|
|
Here is a sample plot script to plot output of the plot command that was
|
||
|
|
stored to plot.dat
|
||
|
|
|
||
|
|
set xlabel "Seconds"
|
||
|
|
set ylabel "dB"
|
||
|
|
set yrange [-60:0]
|
||
|
|
plot 'plot.dat' using 1:2 title 'L RMS' with lines, \
|
||
|
|
'plot.dat' using 1:3 title 'L peak' with lines, \
|
||
|
|
'plot.dat' using 1:4 title 'L decay' with lines
|
||
|
|
|
||
|
|
plot 'plot.dat' using 1:5 title 'R RMS' with lines, \
|
||
|
|
'plot.dat' using 1:6 title 'R peak' with lines, \
|
||
|
|
'plot.dat' using 1:7 title 'R decay' with lines
|
||
|
|
|
||
|
|
|