From b081209514523095ccb05cc5b3afdbb01d48751c Mon Sep 17 00:00:00 2001 From: St33v Date: Wed, 26 Jan 2022 23:10:32 +1100 Subject: rename --- speakerWatchdog.txt | 65 ----------------------------------------------------- 1 file changed, 65 deletions(-) delete mode 100644 speakerWatchdog.txt (limited to 'speakerWatchdog.txt') diff --git a/speakerWatchdog.txt b/speakerWatchdog.txt deleted file mode 100644 index d78c40a..0000000 --- a/speakerWatchdog.txt +++ /dev/null @@ -1,65 +0,0 @@ -#! /bin/bash -# Workaround for stupd 'powersave' 'feature' of Creative Speakers -# -# SJP 11 Dec 2021 -# -# This is just a stub for now - -# Which device is the audio output going to? - -# st33v@cr4y:~$ grep RUNNING /proc/asound/card*/pcm*/sub*/status -# /proc/asound/card2/pcm0p/sub0/status:state: RUNNING - -# That is fine, but the status remains as 'RUNNING' even after the speakers have turned themselves off... -# So I'm going down the track of periodically sending a 'sound' to a loopback device -# sudo modprobe snd-aloop -# Now aply -l shows a new 'card' called Loopback. - - -record one second of default stream: - -$ rec -d -n trim 0 1 stat - - rec sox in record mode - -d default input - -n direct output to /dev/null - trim 0 1 duration 1 second - stat - -Output: - -Input File : 'default' (pulseaudio) -Channels : 2 -Sample Rate : 48000 -Precision : 16-bit -Sample Encoding: 16-bit Signed Integer PCM - -In:0.00% 00:00:01.02 [00:00:00.00] Out:48.0k [ | ] Clip:0 -Samples read: 96000 -Length (seconds): 1.000000 -Scaled by: 2147483647.0 -Maximum amplitude: 0.000000 -Minimum amplitude: 0.000000 -Midline amplitude: 0.000000 -Mean norm: 0.000000 -Mean amplitude: 0.000000 -RMS amplitude: 0.000000 -Maximum delta: 0.000000 -Minimum delta: 0.000000 -Mean delta: 0.000000 -RMS delta: 0.000000 -Rough frequency: -2147483648 -Done. - -So if Max amplitude = 0 then we have silence! - -to generate a tone that is not audible: -play -n synth 1 sine 40 fade .2 0 - - play sox alias - -n dummy input file - synth synthesise a sound - sine sine wave [the default, so not strictly necessary] - 40 Hz - fade fade in from zero volume to max volume over 200 msec. - '0' says fade out at end over same period. -- cgit v1.3