From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id 508004660D for ; Sun, 25 Jun 2023 14:25:48 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 8FA8D68C156; Sun, 25 Jun 2023 17:25:46 +0300 (EEST) Received: from relay2-d.mail.gandi.net (relay2-d.mail.gandi.net [217.70.183.194]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 8896A68BE25 for ; Sun, 25 Jun 2023 17:25:39 +0300 (EEST) X-GND-Sasl: michael@niedermayer.cc Received: by mail.gandi.net (Postfix) with ESMTPSA id BCD9D40007 for ; Sun, 25 Jun 2023 14:25:38 +0000 (UTC) Date: Sun, 25 Jun 2023 16:25:37 +0200 From: Michael Niedermayer To: FFmpeg development discussions and patches Message-ID: <20230625142537.GC3250409@pb2> References: <20230618222805.4054410-1-michael@niedermayer.cc> <20230623111728.GM3250409@pb2> <59E3CAAC-DA7F-424B-ABC1-1E300EA83571@remlab.net> <20230623181241.GN3250409@pb2> MIME-Version: 1.0 In-Reply-To: Subject: Re: [FFmpeg-devel] [PATCH v2] avformat: add Software Defined Radio support X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Content-Type: multipart/mixed; boundary="===============2061475298754200800==" Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: --===============2061475298754200800== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="nQHD+3g9yI+EYXJy" Content-Disposition: inline --nQHD+3g9yI+EYXJy Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Jun 24, 2023 at 10:27:13PM +0200, R=E9mi Denis-Courmont wrote: >=20 >=20 > Le 23 juin 2023 20:12:41 GMT+02:00, Michael Niedermayer a =E9crit=A0: > >Hi > > > >On Fri, Jun 23, 2023 at 06:37:18PM +0200, R=E9mi Denis-Courmont wrote: > >> Hi, > >>=20 > >> Le 23 juin 2023 13:17:28 GMT+02:00, Michael Niedermayer a =E9crit=A0: > >> >On Fri, Jun 23, 2023 at 10:34:10AM +0800, Kieran Kunhya wrote: > >> >> FFmpeg is not the place for SDR. SDR is as large and complex as the > >> >> entirety of multimedia. > >> >>=20 > >> >> What next, is FFmpeg going to implement TCP in userspace, Wifi, Eth= ernet, > >> >> an entire 4G and 5G stack? > >> > > >> >https://en.wikipedia.org/wiki/Straw_man > >> > > >> >What my patch is doing is adding support for AM demodulation, the AM > >> >specific code is like 2 pages. The future plan for FM demodulation wi= ll > >> >not add alot of code either. DAB/DVB should also not be anything big > >> >(if that is implemented at all by anyone) > >>=20 > >> Literally every one of those layer-2 protocols has a lower-level API a= lready on Linux, and typically they are, or would be, backends to libavdevi= ce. > >>=20 > >> (Specifically AM and FM are supported by V4L radio+ALSA; DAB and DVB b= y Linux-DVB. 4G and 5G are network devices.) > > > >4 problems > >* FFmpeg is not "linux only". >=20 > And then what? Whether you like it or not, radio signal processing sits o= n top of OS-specific APIs to access whatever bus or hardware. You can't mak= e this OS-independent whether it's in FFmpeg or elsewhere. >=20 > At best you can write or reuse platform abstraction layers (such as libus= b). Maybe. >=20 > In other words, whether this ends up in FFmpeg or not has absolutely no b= earing on this "problem" as you call it. >=20 > But it doesn't end here. Audio input on Linux is normally exposed with AL= SA modules (hw/plughw if the driver is in kernel, but it doesn't have to be= ), and other OSes have equivalent APIs. A sound (pun unintended) implementa= tion of AM or FM would actually be an ALSA module, and *maybe* also PA and = PW modules. (They don't have to be kernel mode drivers.) >=20 > ...Not an FFmpeg device or demux. >=20 speaking of layers. IMHO the kernel and driver layer should end with the IQ data for SDR. Thats OS specific. After that the whole chain should be largely OS and HW independent turning IQ data to a decoded video and audio stream for DVB is the same on = every OS as complex as it may be. We could feed this back into ALSA on linux but i doubt that would be used a= lot more likely players would link to the library directly that turns IQ -> vid= eo+audio even more so because for the player it would be the same on every platform otherwise the player would have to support platform specific interfaces and= not just one per platform either i think thx [...] --=20 Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Those who are too smart to engage in politics are punished by being governed by those who are dumber. -- Plato=20 --nQHD+3g9yI+EYXJy Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABEIAB0WIQSf8hKLFH72cwut8TNhHseHBAsPqwUCZJhOXQAKCRBhHseHBAsP q6IAAKCC7HH09pmlQWa8G4xyEwmJ5zUNrQCfX/RCuzOjdwYoF1z7L7B6wwwLiik= =RgmS -----END PGP SIGNATURE----- --nQHD+3g9yI+EYXJy-- --===============2061475298754200800== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe". --===============2061475298754200800==--