VDiskIn and 'pitch ratio is greater then max allowed' error

Discussion:

Robert van Heumen

2014-09-26 12:58:47 UTC

Hi.
I created a class DiskPlayer to play files from harddisk. I'm using VDiskIn
with a fixed ratio of 1 for 4-channel audio files. This usually works fine,
but every now and then, when playing 4-channel WAV files, the error 'pitch
ratio is greater then max allowed' happens. I have no clue why this happens.
I'll attach the class file. Any help is appreciated!
Best,
Robert
DiskPlayer.sc
<http://new-supercollider-mailing-lists-forums-use-these.2681727.n2.nabble.com/file/n7613576/DiskPlayer.sc>

-----

*
Robert van Heumen
Composer and improvising musician
http://hardhatarea.com/
--
View this message in context: http://new-supercollider-mailing-lists-forums-use-these.2681727.n2.nabble.com/VDiskIn-and-pitch-ratio-is-greater-then-max-allowed-error-tp7613576.html
Sent from the SuperCollider Users New (Use this!!!!) mailing list archive at Nabble.com.

_______________________________________________
sc-users mailing list

info (subscription, etc.): http://www.beast.bham.ac.uk/research/sc_mailing_lists.shtml
archive: http://www.listarc.bham.ac.uk/marchives/sc-users/
search: http://www.listarc.bham.ac.uk/lists/sc-users/search/

Josh Parmenter

2014-09-26 13:50:47 UTC

Permalink

The max pitch ratio is determined as a function of your buffer size and the speed
You are trying to play at - if you don't have enough read into the buffer to playback at a higher rate, this will post. So - try making the base buffer size a higher power of two, and it should go away.
Best
Josh

/*
Josh Parmenter
www.realizedsound.net/josh
*/

Post by Robert van Heumen
Hi.
I created a class DiskPlayer to play files from harddisk. I'm using VDiskIn
with a fixed ratio of 1 for 4-channel audio files. This usually works fine,
but every now and then, when playing 4-channel WAV files, the error 'pitch
ratio is greater then max allowed' happens. I have no clue why this happens.
I'll attach the class file. Any help is appreciated!
Best,
Robert
DiskPlayer.sc
<http://new-supercollider-mailing-lists-forums-use-these.2681727.n2.nabble.com/file/n7613576/DiskPlayer.sc>
-----
*
Robert van Heumen
Composer and improvising musician
http://hardhatarea.com/
--
View this message in context: http://new-supercollider-mailing-lists-forums-use-these.2681727.n2.nabble.com/VDiskIn-and-pitch-ratio-is-greater-then-max-allowed-error-tp7613576.html
Sent from the SuperCollider Users New (Use this!!!!) mailing list archive at Nabble.com.
_______________________________________________
sc-users mailing list
info (subscription, etc.): http://www.beast.bham.ac.uk/research/sc_mailing_lists.shtml
archive: http://www.listarc.bham.ac.uk/marchives/sc-users/
search: http://www.listarc.bham.ac.uk/lists/sc-users/search/

_______________________________________________
sc-users mailing list

info (subscription, etc.): http://www.beast.bham.ac.uk/research/sc_mailing_lists.shtml
archive: http://www.listarc.bham.ac.uk/marchives/sc-users/
search: http://www.listarc.bham.ac.uk/lists/sc-users/search/

Robert van Heumen

2014-09-27 12:41:14 UTC

Permalink

Hi Josh,
I know about the correlation between buffer size and speed. The thing is, the rate is always 1 and the buffer size is always 65536. I can increase it, see if that works. But it’s puzzling to me.
Thanks,
Robert

Post by Josh Parmenter
The max pitch ratio is determined as a function of your buffer size and the speed
You are trying to play at - if you don't have enough read into the buffer to playback at a higher rate, this will post. So - try making the base buffer size a higher power of two, and it should go away.
Best
Josh
/*
Josh Parmenter
www.realizedsound.net/josh
*/

_______________________________________________
sc-users mailing list
info (subscription, etc.): http://www.beast.bham.ac.uk/research/sc_mailing_lists.shtml
archive: http://www.listarc.bham.ac.uk/marchives/sc-users/
search: http://www.listarc.bham.ac.uk/lists/sc-users/search/

Josh Parmenter

2014-09-27 19:06:07 UTC

Permalink

What is the sample rate for the file and the system?
The disk in ugens fill half the buffer space at a time - so - in this case 32768 for four channels is 8192 frames each go. It could be if you are running multiple instances with different buffers that the disk reads can't keep up. I kind of doubt it, but it is hard to say. Larger buffers, regardless, should help.
Best
Josh

/*
Josh Parmenter
www.realizedsound.net/josh
*/

Post by Robert van Heumen
Hi Josh,
I know about the correlation between buffer size and speed. The thing is, the rate is always 1 and the buffer size is always 65536. I can increase it, see if that works. But it’s puzzling to me.
Thanks,
Robert

_______________________________________________
sc-users mailing list
info (subscription, etc.): http://www.beast.bham.ac.uk/research/sc_mailing_lists.shtml
archive: http://www.listarc.bham.ac.uk/marchives/sc-users/
search: http://www.listarc.bham.ac.uk/lists/sc-users/search/

Robert van Heumen

2014-09-27 20:07:10 UTC

Permalink

Ah, I didnt realise that of course I need a bigger buffer size for 4 channel sound.
Ill do some testing.
Thanks.
Robert

Post by Josh Parmenter
What is the sample rate for the file and the system?
The disk in ugens fill half the buffer space at a time - so - in this case 32768 for four channels is 8192 frames each go. It could be if you are running multiple instances with different buffers that the disk reads can't keep up. I kind of doubt it, but it is hard to say. Larger buffers, regardless, should help.
Best
Josh
/*
Josh Parmenter
www.realizedsound.net/josh
*/

_______________________________________________
sc-users mailing list
info (subscription, etc.): http://www.beast.bham.ac.uk/research/sc_mailing_lists.shtml
archive: http://www.listarc.bham.ac.uk/marchives/sc-users/
search: http://www.listarc.bham.ac.uk/lists/sc-users/search/