[openal] Why ReconstructHrirs in makehrtf?

[Chris Robinson]

On 09/28/2016 09:44 AM, Christian Hoene wrote:
> I do not understand why you need the ReconstructHrirs to generate the HRTFs?
> Actually, all the other signal processing function in makehrtf, are they
> specific to the KEMAR data set?

Hi.

Cool work. I've been hoping to support the SOFA format with makehrtf, 
but haven't gotten the time to.

ReconstructHrirs is used to generate the minimum phase response, which 
drastically cuts down on the impulse response size and makes it more 
efficient to apply in real-time. In the case of KEMAR, it reduces the 
512-sample impulse response to a delay + 32-sample impulse response (it 
does the same for any data set that isn't already minimum phase).

None of the functions are specific to the KEMAR data set, though the 
need for using a given function depends on the data set (e.g. 
ResampleHrirs is unneeded if the input and output samples rates are the 
same, ReconstructHrirs is unneeded if the input is already minimum phase).

Hope that helps. Good luck!