9 Apr
2009
9 Apr
'09
10:24 a.m.
Hi all,
I am using mplayer, sox and tee to capture streaming internet radio
and send it both to an audio recognition program and to a file
(recording).
This is how I do it:
mplayer -playlist {url} -nocache -af volnorm -msglevel all=1 -nolirc
-vc dummy -vo null -ao pcm:file={$fifo1} &
sox -S {$fifo1} -c 1 -r 8000 -t wav - resample | tee {$recording} |
tee {$fifo2} & ......
$fifo1 and $fifo2 are named pipes, $fifo2 is processed by an audio
recognition program. The idea is that the audio is converted to low
quality wav (8000Hz mono) after which it is fed to the program and
simultaneously recorded.
This works great most of the time but sometimes the recording is too
long/slow or too short/fast. Sometimes the speed is slighly wrong and
sometimes it is terribly wrong. When the speed is too slow, I notice
that the file is also much larger and if I open the file in Audacity,
the program tells me that the duration of the recording is for example
two hours in stead of 1 hour (when the speed is twice as slow as it
should be). Below is a list of three recordings that are the product
of this setup. The middle one is larger and when I play it back it is
three times too slow.
55M 2009-04-09 07:00 /data/station_recordings/48_20090409-0600.wav
152M 2009-04-09 06:00 /data/station_recordings/48_20090409-0500.wav
55M 2009-04-09 05:00 /data/station_recordings/48_20090409-0400.wav
My guess is that it has something to do with the sample rate. If
anyone has any idea where this goes wrong or what I could do to try to
fix it, please let me know.
Arnold.
9 Apr
9 Apr
10:53 a.m.
New subject: audio recording through pipe using mplayer and sox sometimes has incorrect speed
On Thu, Apr 9, 2009 at 8:24 AM, Arnold Obdeijn <arnold.obdeijn(a)gmail.com> wrote:
Hi all,
I am using mplayer, sox and tee to capture streaming internet radio
and send it both to an audio recognition program and to a file
(recording).
This is how I do it:
mplayer -playlist {url} -nocache -af volnorm -msglevel all=1 -nolirc
-vc dummy -vo null -ao pcm:file={$fifo1} &
sox -S {$fifo1} -c 1 -r 8000 -t wav - resample | tee {$recording} |
tee {$fifo2} & ......
$fifo1 and $fifo2 are named pipes, $fifo2 is processed by an audio
recognition program. The idea is that the audio is converted to low
quality wav (8000Hz mono) after which it is fed to the program and
simultaneously recorded.
Not that I want to suggest anything to massively off-topic, but I hope
you realize that this is a perfect example of the kind of scenario
that JACK was designed to handle.
Sharing streaming data between programs via pipes is not a great idea
- the buffer associated with a pipe is rather small, and scheduling
delays for the programs reading from the pipe can cause data loss etc.
This doesn't matter if both the writer to the pipe and the reader can
both run "as needed", but when one of them is connected to an i/o
source (eg. the network , or an audio interface) which doesn't buffer
very much and has real deadlines, the whole design is almost destined
to fail or at least be very fragile.
12:44 p.m.
New subject: audio recording through pipe using mplayer and sox sometimes has incorrect speed
On Thu, Apr 9, 2009 at 5:53 AM, Paul Davis <paul(a)linuxaudiosystems.com> wrote:
On Thu, Apr 9, 2009 at 8:24 AM, Arnold Obdeijn
<arnold.obdeijn(a)gmail.com> wrote:
Seconding the jack recommendation, I would recommend using xmms with
the jack output plugin, and record its output with jack_capture.
Mplayer also has a jack output plugin, but xmms has better playlist
support and onscreen controls.
Hi all,
I am using mplayer, sox and tee to capture streaming internet radio
and send it both to an audio recognition program and to a file
(recording).
This is how I do it:
mplayer -playlist {url} -nocache -af volnorm -msglevel all=1 -nolirc
-vc dummy -vo null -ao pcm:file={$fifo1} &
sox -S {$fifo1} -c 1 -r 8000 -t wav - resample | tee {$recording} |
tee {$fifo2} & ......
$fifo1 and $fifo2 are named pipes, $fifo2 is processed by an audio
recognition program. The idea is that the audio is converted to low
quality wav (8000Hz mono) after which it is fed to the program and
simultaneously recorded.
Not that I want to suggest anything to massively off-topic, but I hope
you realize that this is a perfect example of the kind of scenario
that JACK was designed to handle.
Sharing streaming data between programs via pipes is not a great idea
- the buffer associated with a pipe is rather small, and scheduling
delays for the programs reading from the pipe can cause data loss etc.
This doesn't matter if both the writer to the pipe and the reader can
both run "as needed", but when one of them is connected to an i/o
source (eg. the network , or an audio interface) which doesn't buffer
very much and has real deadlines, the whole design is almost destined
to fail or at least be very fragile.
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev(a)lists.linuxaudio.org
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
12:49 p.m.
New subject: audio recording through pipe using mplayer and sox sometimes has incorrect speed
On Thu, Apr 09, 2009 at 07:44:41AM -0700, Justin Smith wrote:
xmms is dead.
> I am using
mplayer, sox and tee to capture streaming internet radio
> mplayer -playlist {url} -nocache -af volnorm -msglevel all=1 -nolirc
Seconding the jack recommendation, I would recommend using xmms with Mplayer also has a jack output plugin, but xmms has
better playlist
support and onscreen controls.
He's capturing internet radio, so he won't probably change stations.
Regarding onscreen control: read the manpage or use gmplayer.
However, you might want to have a look at qmmp.
Cheerio
--
mail: adi(a)thur.de http://adi.thur.de PGP/GPG: key via keyserver
4:17 p.m.
New subject: audio recording through pipe using mplayer and sox sometimes has incorrect speed
On Thu, Apr 9, 2009 at 8:53 AM, Paul Davis <paul(a)linuxaudiosystems.com> wrote:
On Thu, Apr 9, 2009 at 8:24 AM, Arnold Obdeijn
<arnold.obdeijn(a)gmail.com> wrote:
On that note, is there a JACK command-line utility that is as easy to
use as "|"?
That would be cool, if a, b, and c were JACK-enabled applications:
$ jack-pipe a : b : c
So much faster than opening up qjackctl and making connections
manually. Okay, clearly this doesn't handle multichannel very well
however.
Steve
Hi all,
I am using mplayer, sox and tee to capture streaming internet radio
and send it both to an audio recognition program and to a file
(recording).
This is how I do it:
mplayer -playlist {url} -nocache -af volnorm -msglevel all=1 -nolirc
-vc dummy -vo null -ao pcm:file={$fifo1} &
sox -S {$fifo1} -c 1 -r 8000 -t wav - resample | tee {$recording} |
tee {$fifo2} & ......
$fifo1 and $fifo2 are named pipes, $fifo2 is processed by an audio
recognition program. The idea is that the audio is converted to low
quality wav (8000Hz mono) after which it is fed to the program and
simultaneously recorded.
Not that I want to suggest anything to massively off-topic, but I hope
you realize that this is a perfect example of the kind of scenario
that JACK was designed to handle.
4:28 p.m.
New subject: audio recording through pipe using mplayer and sox sometimes has incorrect speed
On Thu, Apr 9, 2009 at 11:17 AM, Stephen Sinclair <radarsat1(a)gmail.com> wrote:
On Thu, Apr 9, 2009 at 8:53 AM, Paul Davis
<paul(a)linuxaudiosystems.com> wrote:
Off the top of my head, something could be put together with a shell
script using the jack_connect program. If you are OK with a single
purpose script that runs and connects two specific known programs,
this will be easy, making it work with arbitrary programs provided as
arguments is better done with something like lash, or patch-bay
persistence.
On Thu, Apr 9, 2009 at 8:24 AM, Arnold Obdeijn
<arnold.obdeijn(a)gmail.com> wrote:
On that note, is there a JACK command-line utility that is as easy to
use as "|"?
That would be cool, if a, b, and c were JACK-enabled applications:
$ jack-pipe a : b : c
So much faster than opening up qjackctl and making connections
manually. Okay, clearly this doesn't handle multichannel very well
however.
Steve
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev(a)lists.linuxaudio.org
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Hi all,
I am using mplayer, sox and tee to capture streaming internet radio
and send it both to an audio recognition program and to a file
(recording).
This is how I do it:
mplayer -playlist {url} -nocache -af volnorm -msglevel all=1 -nolirc
-vc dummy -vo null -ao pcm:file={$fifo1} &
sox -S {$fifo1} -c 1 -r 8000 -t wav - resample | tee {$recording} |
tee {$fifo2} & ......
$fifo1 and $fifo2 are named pipes, $fifo2 is processed by an audio
recognition program. The idea is that the audio is converted to low
quality wav (8000Hz mono) after which it is fed to the program and
simultaneously recorded.
Not that I want to suggest anything to massively off-topic, but I hope
you realize that this is a perfect example of the kind of scenario
that JACK was designed to handle.
4:34 p.m.
New subject: audio recording through pipe using mplayer and sox sometimes has incorrect speed
On Thu, Apr 9, 2009 at 2:28 PM, Justin Smith <noisesmith(a)gmail.com> wrote:
On Thu, Apr 9, 2009 at 11:17 AM, Stephen Sinclair
<radarsat1(a)gmail.com> wrote:
> On Thu, Apr 9, 2009 at 8:53 AM, Paul Davis <paul(a)linuxaudiosystems.com> wrote:
>> On Thu, Apr 9, 2009 at 8:24 AM, Arnold Obdeijn <arnold.obdeijn(a)gmail.com>
wrote:
>>>
> On that note, is there a JACK command-line utility that is as easy to
> use as "|"?
>
> That would be cool, if a, b, and c were JACK-enabled applications:
>
> $ jack-pipe a : b : c
>
>
> So much faster than opening up qjackctl and making connections
> manually. Okay, clearly this doesn't handle multichannel very well
> however.
[ ... ]
Off the top of my head, something could be put
together with a shell
script using the jack_connect program. If you are OK with a single
purpose script that runs and connects two specific known programs,
this will be easy, making it work with arbitrary programs provided as
arguments is better done with something like lash, or patch-bay
persistence.
to be more specific:
----------------------
#!/bin/sh
jackd ... jack arguments here ... &
sleep 2
clientNumberOne &
sleep 2
client NumberThree &
sleep 2
jack_connect system:playback_1 clientNumberOne:in_1
jack_connect system:playback_2 clientNumberOne:in_1
jack_connect system:playback_1 clientNumberTwo:in_1
jack_connect system:playback_2 clientNumberTwo:in_2
----------------------
signal handling to shut down jackd and the two clients is left as an
exercise for the interested.
--p
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev(a)lists.linuxaudio.org
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
5:06 p.m.
New subject: audio recording through pipe using mplayer and sox sometimes has incorrect speed
On that note, is there a JACK command-line utility
that is as easy to
use as "|"?
That would be cool, if a, b, and c were JACK-enabled applications:
$ jack-pipe a : b : c
The gstreamer framework has a pipe-like approach.
See, for instance, the examples here:
http://linux.die.net/man/1/gst-launch-0.10
HTH,
L
5:19 p.m.
New subject: audio recording through pipe using mplayer and sox sometimes has incorrect speed
On Thu, Apr 9, 2009 at 3:06 PM, Luis Garrido
<luisgarrido(a)users.sourceforge.net> wrote:
GStreamer is strictly an *intra* application framework. It has
capability (other than interfacing with JACK) to connect multiple
applications.
On that note,
is there a JACK command-line utility that is as easy to
use as "|"?
That would be cool, if a, b, and c were JACK-enabled applications:
$ jack-pipe a : b : c
The gstreamer framework has a pipe-like approach.
8:28 p.m.
New subject: audio recording through pipe using mplayer and sox sometimes has incorrect speed
GStreamer is strictly an *intra* application
framework. It has
capability (other than interfacing with JACK) to connect multiple
applications.
Indeed (you obviously meant it *hasn't* the capability, of course.)
I didn't explicit clearly the context of my answer, sorry. I was more
thinking about the OP's situation and offering another possibility:
instead of jackifying his audio recognition program he could turn it
into a gstreamer plugin. There are advantages and disadvantages to
each of those solutions. A gstreamer plugin would be somewhat more
complicated to develop but in turn he wouldn't need mplayer, sox or
any external plumbing.
L
18 Apr
18 Apr
7:28 a.m.
New subject: audio recording through pipe using mplayer and sox sometimes has incorrect speed
On Thu, 2009-04-09 at 14:34 -0400, Paul Davis wrote:
On Thu, Apr 9, 2009 at 2:28 PM, Justin Smith
<noisesmith(a)gmail.com> wrote:
Off the top of my head, something could be put together with a shell
It'd be nice to have a utility in jack that would work like this:
jack_waitForClient clientNumberOneName
or something similar... returns when the named port is available
(hopefully signalling that the application is ready, at least from the
point of view of jack connections)
-- Fernando
script using the jack_connect program. If you are
OK with a single
purpose script that runs and connects two specific known programs,
this will be easy, making it work with arbitrary programs provided as
arguments is better done with something like lash, or patch-bay
persistence.
to be more specific:
----------------------
#!/bin/sh
jackd ... jack arguments here ... &
sleep 2
clientNumberOne &
sleep 2 client NumberThree &
sleep 2
jack_connect system:playback_1 clientNumberOne:in_1
jack_connect system:playback_2 clientNumberOne:in_1
jack_connect system:playback_1 clientNumberTwo:in_1
jack_connect system:playback_2 clientNumberTwo:in_2
----------------------
signal handling to shut down jackd and the two clients is left as an
exercise for the interested.
--p
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev(a)lists.linuxaudio.org
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev(a)lists.linuxaudio.org
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
5515
days inactive
5524
days old
linux-audio-dev@lists.linuxaudio.org
10 comments
7 participants
participants (7)
-
adi＠drcomp.erfurt.thur.de -
Arnold Obdeijn -
Fernando Lopez-Lezcano -
Justin Smith -
Luis Garrido -
Paul Davis -
Stephen Sinclair