Hi list,
I have a SuperCollider project that I wish to run headless on a
Raspberry Pi 3. While it has no GUI, one of the classes that I defined
inherits from another QT dependent class so it's necessary to use Xvfb
when not using X forwardin over ssh or running headless.
To test, I'm using SuperCollider file (.scd) which pushes the Pi quite a
bit, to the point where there are occasional jack overruns when I launch
sclang and the scd file manually in a terminal. It's pushed hard, but
does run without failing.
What I'm having trouble with is getting it to run from startup. When I
run it manually, the 4 CPU cores of the Pi are running at between 40 and
55% capacity. All fine. However when I run from startup (and if I'm able
to make a reading before it locks up), the CPUs run at between 70-100%.
I am able to run less demanding scd files with no problems at startup,
just not the more demanding ones.
To run from startup there is a crontab entry for the user pi with the
following:
@reboot cd /home/pi && ./runproject.sh
The runproject.sh script contains the following:
#!/bin/bash
PATH=$PATH:/usr/local/bin
sleep 10
export DISPLAY=:99
Xvfb $DISPLAY -screen 0 1024x768x16 &
sleep 5
/usr/bin/jackd -P75 -dalsa -dhw:0 -r44100 -p1024 -n3 -P&
sleep 15
cd /home/pi
sclang project.scd
exit 0
It's not normally necessary to run jackd independently of sclang, but I
found it helped to avoid heavy distortion from overruns. I'm
experimenting with various sleep values in various positions too, but I
can't seem to emulate a manual start in the terminal. Usually, when
running demanding scd files, an autostart from cron results in far more
overruns or the system freezing up entirely. I've piped the standard out
sclang to file and there's no errors.
Can anyone suggest a better approach?
Thanks,
Iain
This sequence, is needed to make my USB-to-MIDI cable work while
connected from the beginning:
1. Power on the Linux box
2. Wait until all processes are running and connected
3. Power on the keyboard
I'm connecting ALSA MIDI and JACK via aj-snapshot after all processes
are up.
If I use ALSA MIDI, via a2jmidid or a2jmidi_bridge, the above is
needed. If I use JACK MIDI, the keyboard has to be on first. Any
thoughts as to whether this is to be expected?
--
Jonathan E. Brickman jeb(a)ponderworthy.com (785)233-9977
Hear us at http://ponderworthy.comcom -- CDs and MP3 now available!
Music of compassion; fire, and life!!!
I read this mailing list via Gmane and it appears like it has been
unsubscribed about a week ago. Anybody have any idea how one can
reenable this?
--
David Kastrup
Hey hey,
I'm just trying to concatenate two mpeg4 videos that I have created with
ffmpeg. One has a series of images (a true video), the other just has a still.
Here's how they were created:
ffmpeg -loop 1 -y -i image.jpg -i sound.wav -acodec aac -vcodec mpeg4 -s
1280x720 -shortest result.mp4
(the options from -vcodec to -s were later exchanged for the ones in the
commandline below, almost same result)
ffmpeg -r 24 -start_number 1 -i image%03d.jpg -c:v libx264 -r 24 -pix_fmt
yuv420p -i sound.wav -acodec aac out.mp4
(swapped the first commandline for everything from -c:v to -pix_fmt)
For concatenation I tried:
ffmpeg -f concat -safe 0 -i mylist.txt -c copy output.mp4
(where mylist.txt contained lines:
file file1.mp4
...
I also tried converting the mpeg4s to intermediate .ts files:
ffmpeg -i input1.mp4 -c copy -bsf:v h264_mp4toannexb -f mpegts
intermediate1.ts
...
And then used:
ffmpeg -i "concat:intermediate1.ts|intermediate2.ts" -c copy -bsf:a
aac_adtstoasc output.mp4
With the original options for the first and second video, the direct
concatenation failed, because they apparently had different video/image
formats.
After rerendering the still, they'd concatenate, but only play the first
(moving) video correctly and then just skip through the rest. The same for the
second concatenation method with intermediate .ts files.
Can anyone point out where I went wrong. Or even better give me a few correct
commandlines. :)
--------
* website: http://juliencoder.de - for summer is a state of sound
* SoundCloud: https://soundcloud.com/jeanette_c
Don't care about money
It doesn't give me half the thrill <3
(Britney Spears)
Hey hey everyone,
it's been a long time, since I worked with WFS. It appears that SWONDER is
really dead now and so I'm looking for a different tool, in which I could set
up audio for WFS using the console. Parameter control over OSC or MIDI would
be nice, so it could be hooked up to Csound. Any ideas are welcome.
Best wishes,
Jeanette
--------
* website: http://juliencoder.de - for summer is a state of sound
* SoundCloud: https://soundcloud.com/jeanette_c
Where are you now, what have you found
Where is your heart, when I'm not around <3
(Britney Spears)
Anyone got any experience of this unit. It looks very good (on paper), seems to
have been in production for about 4 years, and is a very attractive price from
the usual suspects.
It appears to be class complient, and unlike many others doesn't have a lot of
internal routing and effects. This suits me fine - no obscure windows only
software controls!
--
Will J Godfrey
http://www.musically.me.uk
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.
Greetings,
Does anyone here have experience with rtl-sdr, ideally on Fedora ? I'll
receive my hardware tomorrow, I'd like to get up & running asap, so any
tips would be much appreciated.
I'm on Fedora 23, and I already know about http://rtlsdr.org/ and
http://www.rtlsdr.com/.
Btw, I'm interested in this stuff because of a relevant module for
VCV-Rack (and because it looks like fun).
Best,
dp
