220 26169 <3c0fde91-671d-4751-955d-7b04cfa120bc@isocpp.org> article Path: news.gmane.org!not-for-mail From: alexander.zywicki@gmail.com Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Any interest to adding audio support to the std library? Date: Fri, 3 Jun 2016 21:04:20 -0700 (PDT) Lines: 449 Approved: news@gmane.org Message-ID: <3c0fde91-671d-4751-955d-7b04cfa120bc@isocpp.org> References: <5751B06A.4080501@mail1.stofanet.dk> <5290948.va25uYNizX@tjmaciei-mobl1> <1580229.cHEgQxCuA1@tjmaciei-mobl1> <62b7649a-5de5-4330-9bac-708375d36e2c@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_2708_1354587437.1465013060639" X-Trace: ger.gmane.org 1465013115 26159 80.91.229.3 (4 Jun 2016 04:05:15 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 4 Jun 2016 04:05:15 +0000 (UTC) To: ISO C++ Standard - Future Proposals Original-X-From: std-proposals+bncBCS7TY6DTQOBBRVGZG5AKGQEWS4NFCA@isocpp.org Sat Jun 04 06:05:10 2016 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qk0-f199.google.com ([209.85.220.199]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1b92ox-0003GO-Vd for gclcip-std-proposals@m.gmane.org; Sat, 04 Jun 2016 06:04:24 +0200 Original-Received: by mail-qk0-f199.google.com with SMTP id g77sf239039803qke.3 for ; Fri, 03 Jun 2016 21:04:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isocpp-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:message-id:in-reply-to:references:subject:mime-version :x-original-sender:reply-to:precedence:mailing-list:list-id :x-spam-checked-in-group:list-post:list-help:list-archive :list-subscribe:list-unsubscribe; bh=MYD3wZxeN8cPBCjMe6AAYUz6KbVUUDS+39JSagtc74w=; b=Ul55ktfOgJsJDDPLE9CKehwdojG0ET6dMgoYRcCvt0WkwC1X4zbH5Bqs+vM9pYEvFq qCA2hzo2GD8g2EGUWH83dekhPii2m2G4JVhOZy8ObsiZnD/F3yCSsFgQhex5pdEN50VK Y3GdDNZPVi3nsv66avD+zknpkypZ3WgA19if9OwM2g3FWpcma3Ua+07kakmgDmGDx9Yq JAOvyXHG08eWQkSC+4tNEfK8THoxqkULXWs+P0JSJxhIC+g5362SLHLH3g6mB8HKy0R7 ujSrN8hx8aAxweheqGexY3Kwu6EtVDfDGDP6vBudQwRwvs3p856C4Y1EbQtx0lUn0yF3 jkng== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:message-id:in-reply-to:references:subject:mime-version :x-original-sender:reply-to:precedence:mailing-list:list-id :x-spam-checked-in-group:list-post:list-help:list-archive :list-subscribe:list-unsubscribe; bh=MYD3wZxeN8cPBCjMe6AAYUz6KbVUUDS+39JSagtc74w=; b=dyvBThjf8onDvubu3tzrisz2EVf+j4X6Su/fGu2yFBQwwYLFWfSCkeiSEybznec40Z tlhhNTkrBRjR9W7hUkSfT08S+w9ay4lJNFANyC8waBtenW4y8KidR0Oa17+L+s7kEEwi j7tivr+M3D2peNIR8CenFTXRWxIqjKrzgCCVDb8TKj7v+8LR5QRlWjiWA3i4C0h4k2Ql WVwjKgCnDbbi9SJ5LTb5uaPNR3ZLe/Sf/FF1muCre0f+Z6qXnV2t13pw0ZfC9jVjMF7+ op08sK0UOz6/y+7rRcJNQ95S043+DzG9cbtPif0LjwSsa0jt4iGNxmFs35wVLDEx2jsh 5exA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:message-id:in-reply-to:references :subject:mime-version:x-original-sender:reply-to:precedence :mailing-list:list-id:x-spam-checked-in-group:list-post:list-help :list-archive:list-subscribe:list-unsubscribe; bh=MYD3wZxeN8cPBCjMe6AAYUz6KbVUUDS+39JSagtc74w=; b=ejd0WC8MFVXIE9B9BB1dNp1eNkh6H0a2u9JOZAZn66wgLPXrkqhjCYVM51e5CIct27 6L9+KSYfXRKpX/v3i0UTXazKJrKI1Yei9Xjkd5jv0WK8mBO4u+QnbdJtpYrKwJJlBSdh tyyay0HRX3LDn1yfgD4W0N91grLjPqG20EnQ+VxpwpO4+hqJ0Cc2g4ZmmPbsITxrhCTj LndiuWS4hlO37ohw1FRUprG11UDeTa71U+2CGIqKoaypcmYNrq9pU6+buPM+1tzHZ6C+ nVJ3BWdg/JbT72pFhjwGfCMGlq7/2LfoDYbEi54DyEY6CqhnGtGZLU+Xc3CEb59UziUC K/VA== X-Gm-Message-State: ALyK8tJTaQLcDjxYv2ygoHEmdW1+8J0OVSZ3UZ9e/6rGjgn5KnB5JjeLz9DP2h8VUI3qDQ== X-Received: by 10.140.29.101 with SMTP id a92mr5083257qga.24.1465013062920; Fri, 03 Jun 2016 21:04:22 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.36.92.16 with SMTP id q16ls158528itb.12.gmail; Fri, 03 Jun 2016 21:04:21 -0700 (PDT) X-Received: by 10.36.36.211 with SMTP id f202mr91892ita.8.1465013061921; Fri, 03 Jun 2016 21:04:21 -0700 (PDT) In-Reply-To: X-Original-Sender: alexander.zywicki@gmail.com Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Spam-Checked-In-Group: std-proposals@isocpp.org X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:26169 Archived-At: ------=_Part_2708_1354587437.1465013060639 Content-Type: multipart/alternative; boundary="----=_Part_2709_948455483.1465013060639" ------=_Part_2709_948455483.1465013060639 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable I have drafted up a list of basic definitions about how audio could be=20 represented based on your comment here. I think if we are to attempt to=20 move forward a consensus must be reached about the fundamental=20 representation of audio data the library will take.=20 C++ std::audio library theory and definitions: sample: a single sample of audio data. can be represented by a signed integer, float or double. must pass the following test to be a valid sample type: ((std::is_integral::value && std::is_signed::value) ||=20 std::is_floating_point::value) =3D=3D true or could be constrained by: std::is_arithmetic::value=3D=3Dtrue if unsigned samples are allowed/desired frame: a collection of 0-N samples each sample represents an individual channel of audio data indexable as an array (should N be runtime or compile time?) buffer: a collection of 0-N frames indexable as an array (should N be runtime or compile time?) ideally maintains a continous piece of memory to house its frames device /interface: a device recognized by the system as being capable of reading and=20 writing audio data can be polled for information regarding the capabilities of the=20 device/interface audio callback: a function/lambda/functor registered with the library to be called once= =20 per buffer interval sampling rate: the number of samples per second of audio data frame interval: the length of a frame in seconds (1.0/sample_rate) buffer interval: the length of a buffer in seconds (frame_interval*=20 buffer_size) What should be added/removed/edited or clarified? On Friday, June 3, 2016 at 9:11:26 PM UTC-5, Ron wrote: > > Okay, I've done some thinking here. The simplest solution should be the= =20 > correct one. I think the standard should stick to something very basic= =20 > here, otherwise we get into an area that is too complicated to implement.= =20 > All we should have in terms of a standard audio interface for C++ is: > > 1) A method for enumerating the interfaces on a machine. > 2) A method for getting each interfaces capabilities (supported rates, bi= t=20 > depths etc.). > 3) A method for activating a requested device for sending and receiving= =20 > frames in the requested format. > > Valid types for audio samples should be either a signed integer, a float= =20 > or a double. And that's pretty much it. Get audio input, put audio=20 > output. Anything other than that would be a different proposal all=20 > together. Audio, video or DSP processing in general should certainly be = a=20 > different proposal. > > But I would propose we also add an int24_t class into the standard for=20 > processing 24-bit samples. Something as simple as this would suffice for= =20 > now: > class int24_t > { > private: > int8_t val[3]; > }; > > Something more fully featured would be desirable, like this:=20 > https://github.com/RonNovy/CppDSP/blob/master/src/int24_t.h > But I guess that, would be another proposal. > > On Fri, Jun 3, 2016 at 6:47 PM, >=20 > wrote: > >> On Friday, June 3, 2016 at 8:30:49 PM UTC-5, Jeffrey Yasskin wrote: >> > On Fri, Jun 3, 2016 at 6:09 PM, Thiago Macieira = =20 >> wrote: >> > On s=C3=A1bado, 4 de junho de 2016 02:20:15 BRT Andrey Semashev wrote: >> > >> > > What is needed is a standardized interface for these different modul= es >> > >> > > to work with each other. The interface should also allow me, the >> > >> > > developer, to work with the media (e.g. create my own audio or image >> > >> > > filter or a new codec or a new device driver). >> > >> > >> > >> > That I agree with. >> > >> > >> > >> > But should the standard mandate that there should be at least one? How= =20 >> does >> > >> > someone write a plugin to the C++ Standard Library? Will we now mandat= e=20 >> this >> > >> > kind of ability? >> > >> > >> > >> > Yes. We already do this with things like the random engines. >> > >> > >> > If not, then will there be a requirement that the C++ library vendor= =20 >> provide >> > >> > it? If so, please think carefully how Apple should code libc++ to work= =20 >> on iOS. >> > >> > >> > >> > WebCrypto has an example of navigating a legal minefield for=20 >> implementers. >> > >> > >> > >> > Also remember to leave the legal speculation to lawyers. It's good to= =20 >> have the heads-up that "hey lawyers should look at this", but anything m= ore=20 >> is unwise. >> > >> > >> > Again, I think this is not material for the C++ Standard Library. >> > >> > >> > I think it's a great area for the C++ library to expand into. I'm=20 >> definitely worried about the expertise of the people writing the proposa= l=20 >> (e.g. if I proposed an audio library for C++, I should be laughed off th= e=20 >> stage), but we can overcome that by asking well-known audio users for th= eir=20 >> opinions before standardizing the proposal. >> > >> > >> > Jeffrey >> >> I agree about the issue of expertise. By no means would I call myself an= =20 >> expert, but I have a degree in audio engineering and a pretty solid gras= p=20 >> of the c++ language. Are there people out there more skilled than me at= =20 >> each topic? Of course, but that's why I am here, to get the opinions of= =20 >> those people if I can an figure out what needs to be done to make this= =20 >> library a reality. >> >> -- >> You received this message because you are subscribed to the Google Group= s=20 >> "ISO C++ Standard - Future Proposals" group. >> To unsubscribe from this group and stop receiving emails from it, send a= n=20 >> email to std-proposal...@isocpp.org . >> To post to this group, send email to std-pr...@isocpp.org . >> To view this discussion on the web visit=20 >> https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/62b7649a-5d= e5-4330-9bac-708375d36e2c%40isocpp.org >> . >> > > --=20 You received this message because you are subscribed to the Google Groups "= ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. To view this discussion on the web visit https://groups.google.com/a/isocpp= ..org/d/msgid/std-proposals/3c0fde91-671d-4751-955d-7b04cfa120bc%40isocpp.or= g. ------=_Part_2709_948455483.1465013060639 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
I have drafted up a list of basic definitions about how au= dio could be represented based on your comment here. I think if we are to a= ttempt to move forward a consensus must be reached about the fundamental re= presentation of audio data the library will take.

C++ std::audio library

theory and definitions:
=
=C2=A0=C2=A0=C2=A0 sample:
=C2=A0=C2=A0=C2=A0 a single sample of aud= io data.
=C2=A0=C2=A0=C2=A0 can be represented by a signed integer, floa= t or double.
=C2=A0=C2=A0=C2=A0 must pass the following test to be a val= id sample type:
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ((std::is_int= egral<T>::value && std::is_signed<T>::value) || std::is= _floating_point<T>::value) =3D=3D true
=C2=A0=C2=A0=C2=A0 or could= be constrained by:
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 std= ::is_arithmetic<T>::value=3D=3Dtrue
=C2=A0=C2=A0=C2=A0=C2=A0 if un= signed samples are allowed/desired

=C2=A0=C2=A0=C2=A0 frame:
=C2= =A0=C2=A0=C2=A0 a collection of 0-N samples
=C2=A0=C2=A0=C2=A0 each samp= le represents an individual channel of audio data
=C2=A0=C2=A0=C2=A0 ind= exable as an array
=C2=A0=C2=A0=C2=A0 (should N be runtime or compile ti= me?)

=C2=A0=C2=A0=C2=A0 buffer:
=C2=A0=C2=A0=C2=A0 a collection o= f 0-N frames
=C2=A0=C2=A0=C2=A0 indexable as an array
=C2=A0=C2=A0=C2= =A0 (should N be runtime or compile time?)
=C2=A0=C2=A0=C2=A0 ideally ma= intains a continous piece of memory to house its frames

=C2=A0=C2=A0= =C2=A0 device /interface:
=C2=A0=C2=A0=C2=A0 a device recognized by the = system as being capable of reading and writing audio data
=C2=A0=C2=A0= =C2=A0 can be polled for information regarding the capabilities of the devi= ce/interface


=C2=A0=C2=A0=C2=A0 audio callback:
=C2=A0=C2=A0= =C2=A0 a function/lambda/functor registered with the library to be called o= nce per buffer interval

=C2=A0=C2=A0=C2=A0 sampling rate: the number= of samples per second of audio data

=C2=A0=C2=A0=C2=A0 frame interv= al: the length of a frame in seconds (1.0/sample_rate)
=C2=A0=C2=A0=C2= =A0 buffer interval: the length of a buffer in seconds (frame_interval* buf= fer_size)

What should be added/remo= ved/edited or clarified?


On Friday, June 3, 2016 at = 9:11:26 PM UTC-5, Ron wrote:
Okay, I've done some thinking here.=C2=A0 The simpl= est solution should be the correct one.=C2=A0 I think the standard should s= tick to something very basic here, otherwise we get into an area that is to= o complicated to implement.=C2=A0 All we should have in terms of a standard= audio interface for C++ is:

1) A method for enume= rating the interfaces on a machine.
2) A method for getting each = interfaces capabilities (supported rates, bit depths etc.).
3) A = method for activating a requested device for sending and receiving frames i= n the requested format.

Valid types for audio samp= les should be either a signed integer, a float or a double.=C2=A0 And that&= #39;s pretty much it.=C2=A0 Get audio input, put audio output.=C2=A0 Anythi= ng other than that would be a different proposal all together.=C2=A0 Audio,= video or DSP processing in general should certainly be a different proposa= l.

But I would propose we also add an int24_t clas= s into the standard for processing 24-bit samples.=C2=A0 Something as simpl= e as this would suffice for now:
class int24_t
{
<= div>private:
=C2=A0 =C2=A0 int8_t val[3];
};
=
Something more fully featured would be desirable, like this:= https://github.com/RonNovy/CppD= SP/blob/master/src/int24_t.h
But I guess that, would be = another proposal.

On Fri, Ju= n 3, 2016 at 6:47 PM, <alexande...@gmail.com> wrote:
On Friday, June 3, 2016 at 8:30:= 49 PM UTC-5, Jeffrey Yasskin wrote:
> On Fri, Jun 3, 2016 at 6:09 PM, Thiago Macieira <thi...@ma= cieira.org> wrote:
> On s=C3=A1bado, 4 de junho de 2016 02:20:15 BRT Andrey Semashev wrote:=
>
> > What is needed is a standardized interface for these different mo= dules
>
> > to work with each other. The interface should also allow me, the<= br> >
> > developer, to work with the media (e.g. create my own audio or im= age
>
> > filter or a new codec or a new device driver).
>
>
>
> That I agree with.
>
>
>
> But should the standard mandate that there should be at least one? How= does
>
> someone write a plugin to the C++ Standard Library? Will we now mandat= e this
>
> kind of ability?
>
>
>
> Yes. We already do this with things like the random engines.
>
>
> If not, then will there be a requirement that the C++ library vendor p= rovide
>
> it? If so, please think carefully how Apple should code libc++ to work= on iOS.
>
>
>
> WebCrypto has an example of=C2=A0navigating a legal minefield for impl= ementers.
>
>
>
> Also remember to leave the legal speculation to lawyers. It's good= to have the heads-up that "hey lawyers should look at this", but= anything more is unwise.
>
>
> Again, I think this is not material for the C++ Standard Library.
>
>
> I think it's a great area for the C++ library to expand into. I= 9;m definitely worried about the expertise of the people writing the propos= al (e.g. if I proposed an audio library for C++, I should be laughed off th= e stage), but we can overcome that by asking well-known audio users for the= ir opinions before standardizing the proposal.
>
>
> Jeffrey

I agree about the issue of expertise. By no means would I call mysel= f an expert, but I have a degree in audio engineering and a pretty solid gr= asp of the c++ language. Are there people out there more skilled than me at= each topic? Of course, but that's why I am here, to get the opinions o= f those people if I can an figure out what needs to be done to make this li= brary a reality.

--
You received this message because you are subscribed to the Google Groups &= quot;ISO C++ Standard - Future Proposals" group.
To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposal...@isocpp.org.
To post to this group, send email to std-pr...@isocpp.org.
To view this discussion on the web visit https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/62b= 7649a-5de5-4330-9bac-708375d36e2c%40isocpp.org.

--
You received this message because you are subscribed to the Google Groups &= quot;ISO C++ Standard - Future Proposals" group.
To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposa= ls+unsubscribe@isocpp.org.
To post to this group, send email to std-proposals@isocpp.org.
To view this discussion on the web visit https://groups.google.= com/a/isocpp.org/d/msgid/std-proposals/3c0fde91-671d-4751-955d-7b04cfa120bc= %40isocpp.org.
------=_Part_2709_948455483.1465013060639-- ------=_Part_2708_1354587437.1465013060639 Content-Type: text/plain; charset=US-ASCII; name=std_audio_theories_concepts.txt Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=std_audio_theories_concepts.txt X-Attachment-Id: 6627695d-c41d-48ad-b42f-b3a67af03d47 Content-ID: <6627695d-c41d-48ad-b42f-b3a67af03d47> C++ std::audio library theory and definitions: sample: a single sample of audio data. can be represented by a signed integer, float or double. must pass the following test to be a valid sample type: ((std::is_integral::value && std::is_signed::value) || std::is_floating_point::value) == true or could be constrained by: std::is_arithmetic::value==true if unsigned samples are allowed/desired frame: a collection of 0-N samples each sample represents an individual channel of audio data indexable as an array (should N be runtime or compile time?) buffer: a collection of 0-N frames indexable as an array (should N be runtime or compile time?) ideally maintains a continous piece of memory to house its frames device /interface: a device recognized by the system as being capable of reading and writing audio data can be polled for information regarding the capabilities of the device/interface audio callback: a function/lambda/functor registered with the library to be called once per buffer interval sampling rate: the number of samples per second of audio data frame interval: the length of a frame in seconds (1.0/sample_rate) buffer interval: the length of a buffer in seconds (frame_interval* buffer_size) ------=_Part_2708_1354587437.1465013060639-- .