Need help - how to change velocity/tempo using OpenAL?

Audio and Graphics
#1

Using the very lightly-documented examples here (http://www.coronalabs.com/blog/2011/07/27/the-secretundocumented-audio-apis-in-corona-sdk/) I’ve managed to be able to up the pitch an octave using this:

al.Source(source, al.PITCH, 2)

But now the sound is playing at 2x tempo.  I’m assuming that using al.SpeedOfSound or al.Velocity or some other method I can utilize OpenAl to bring the tempo back down to 1x.   I’ve been searching far and wide and can’t seem to come up with any good examples or documentation.

Can anyone help?  Thanks!

#2

Anyone from Corona able to help with this?  Pitch changes working great, just struggling with how to alter tempo… 

#3

Because its undocumented really can’t offer support on the undocumented features, but I’ll ask and see if there is any engineering time to look into how this works.

Rob

#4

Sounds great - thanks Rob.  The link to the “secret undocumented…” page has a lot of info on it but only seems to apply to a few types of function calls - pitch and position.   And, the lua demo on github also only addresses pitch and position.  But, there appears to be a number of other exposed functions here.  Really just need some pointers and maybe a few quick examples to point me in the right direction.  Otherwise I’m developing blind here.  Resouces online for this are a bit lacking, and even trying to decipher the C code in the documentation I have been able to find, then applying that to some test Lua code in Corona, hasn’t worked…

#5

Have the engineers looked that this?

 http://theamazingaudioengine.com

I wonder if it could be integrated with Corona (or maybe as plugin)?

#6

iOS only so I dont think that aligns with Corona’s cross-platform objective.

#7

Anyone from Corona able to help with this?  Pitch changes working great, just struggling with how to alter tempo… 

#8

Because its undocumented really can’t offer support on the undocumented features, but I’ll ask and see if there is any engineering time to look into how this works.

Rob

#9

Sounds great - thanks Rob.  The link to the “secret undocumented…” page has a lot of info on it but only seems to apply to a few types of function calls - pitch and position.   And, the lua demo on github also only addresses pitch and position.  But, there appears to be a number of other exposed functions here.  Really just need some pointers and maybe a few quick examples to point me in the right direction.  Otherwise I’m developing blind here.  Resouces online for this are a bit lacking, and even trying to decipher the C code in the documentation I have been able to find, then applying that to some test Lua code in Corona, hasn’t worked…

#10

Have the engineers looked that this?

 http://theamazingaudioengine.com

I wonder if it could be integrated with Corona (or maybe as plugin)?

#11

iOS only so I dont think that aligns with Corona’s cross-platform objective.