'Sound' package likey has no way to set sample format

[sergstesh]

Looking into PortAudio documentation, e.g. at https://files.portaudio.com/docs/v19-doxydocs-dev/portaudio_8h.html#a4582d93c2c2e60e12be3d74c5fe00b , which describes 'PaSampleFormat' type, I see that there is a number of sample formats supported.

Also in https://files.portaudio.com/docs/v19-doxydocs-dev/portaudio_8h_source.html I see on line #498 '#define paCustomFormat ((PaSampleFormat) 0x00010000)' . I in practice specifically need S24_3LE for the capture stream of CX31993 because it's the only 24 bit format the ADC supports.

Looking into https://jefffessler.github.io/Sound.jl/stable/methods/#Methods-list I don't see a way to set sample format.

Am I missing something ?

For that matter, looking into https://github.com/JuliaAudio/PortAudio.jl I am not sure it implements setting sample format - I mean number of bits per sample and how the bits are packed in a sample - again, I particularly need S24_3LE.

At the moment I've implemented my code the Linux-only way using 'aplay' and 'arecord' - the two utilities allow me to set whatever sample format supported by the card. I would rather prefer to implement my code cross=platform way.

[JeffFessler]

The input signal to the sound function is x::AbstractArray which is quite general.
If your data is of that type then Sound can accept it.
That input is simply passed to PortAudio; if you get an error there then you should post an issue in that repo.
My guess is you will need to go even lower and work with https://github.com/JuliaAudio/SampledSignals.jl

[sergstesh]

My guess is you will need to go even lower and work with https://github.com/JuliaAudio/SampledSignals.jl

I visited the link before opening this issue and didn't find what I was looking for. I.e. IMO nothing that is stuff like S24_3LE.

Am I missing something ?

[sergstesh]

The input signal to the sound function is x::AbstractArray which is quite general.

I do not understand whether the quoted statement is relevant for the reported issue.

If I understand you correctly, the quoted statement is about the following https://jefffessler.github.io/Sound.jl/stable/methods/#Sound.sound :

Play monophonic audio signal x at sampling rate S samples per second through default audio output device using the PortAudio package. Caller must specify S unless a framerate method is defined for x.

First of all, I am at the moment interested in specifying capture format (pay attention to "ADC" in my opening statement - which is not DAC) rather than in playback format.

[JeffFessler]

Ah sorry, I overlooked the "ADC" focus.
The only input-related function here is record https://github.com/JeffFessler/Sound.jl/blob/main/src/record.jl
And that function in turn simply calls PortAudio's read function so I think you'll have to look there.
TBH, Sound was designed primarily for DAC in a course setting, and ADC is just a small add-on.
I welcome PRs but I won't have time to work on enhancing record myself.

[sergstesh]

Ah sorry, I overlooked the "ADC" focus. The only input-related function here is record https://github.com/JeffFessler/Sound.jl/blob/main/src/record.jl And that function in turn simply calls PortAudio's read function so I think you'll have to look there. TBH, Sound was designed primarily for DAC in a course setting, and ADC is just a small add-on. I welcome PRs but I won't have time to work on enhancing record myself.

Then I suggest to update the package documentation to state there is no way to explicitly set sample format the way PortAudio "C" library allows to do it.