I need a system where the starting of the playback/recording has systematic (and minimal) delays.
When I do a test with two computers (with accurate GPS clocks) running two shell script:
Script in computer 1:
---------------------
STARTTIME1=`date +%y%m%d%H%M%S%N`
echo 'Recording started at' $STARTTIME1
nice -n -20 arecord -D plughw:0,1 -t wav -f cd -d 60 $FILENAME
STOPTIME1=`date +%y%m%d%H%M%S%N`
echo 'Recording stopped at' $STOPTIME1
Script in computer 2: --------------------- STARTTIME2=`date +%y%m%d%H%M%S%N` echo 'Playback started at' $STARTTIME2 nice -n -20 aplay -D plughw:0,0,0 -f cd track_xx.wav STOPTIME2=`date +%y%m%d%H%M%S%N` echo 'Playback stopped at' $STOPTIME2
The scripts are launched from crontab and the output of the computer 2 is connected to input of computer 1.
There are systematic delays in the variables STARTTIME2 and STOPTIME2 (within 1ms, good enough!) (the playback) and in the variable STARTTIME1. BUT when I look inside the captured file FILENAME, there is a random (!?!) delay within 500 ms in the audio and the variable STOPTIME2 has a random delay within 1000ms (doesn't correlate very well with the delay in the captured audio).
I wonder if there is something to do with the recording (ALSA 0.9.6., card RME Digi96/8 PST using ADAT optical input). Does the random delay have something to do with the initialization of the sound driver? Or is there a better way to test this delay?
Yours, panu
------------------------------------------------------- This SF.net email is sponsored by: SF.net Giveback Program. Does SourceForge.net help you be more productive? Does it help you create better code? SHARE THE LOVE, and help us help YOU! Click Here: http://sourceforge.net/donate/ _______________________________________________ Alsa-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-user
