Playing BBC R3 FLAC files recorded by nightly VLC

[Vangelis forthnet]

 People, people...

 When I first mentioned VLC-3.0.0-git (Nightly) as a means of
recording the R3 flac MPEG-DASH stream, it was never my
intention to contribute to the creation of a protracted OT thread;
my references to VLC were terse on purpose and assumed some
user familiarity; even if that wasn't the case, VLC has
online documentation
http://www.videolan.org/support/
wiki
https://wiki.videolan.org/Documentation:VLC_for_dummies
https://wiki.videolan.org/Knowledge_Base
forum
https://forum.videolan.org/
and user mailing list:
https://mailman.videolan.org/listinfo/vlc
Any more niche queries can be usually
answered by searching specialised fora
like videohelp, doom9, hydrogenaudio etc.

@Richard (and possibly others):
Yes, you need to preconfigure your VLC recordings
directory prior to starting a stream recording (any stream);
never mind setting a recording filename, VLC can work its
way creating meaningful unique filenames with timestamps
(e.g. vlc-record-2017-08-06-22h38m21s-Radio 3 lossless-.ogg).

VLC Nightly issues:

 Just a WORD OF CAUTION for those having an installed
VLC 2.2.x copy on Windows: the default/user settings of VLC are
stored in %APPDATA%\vlc ; you'd better make a backup of that
dir prior to executing VLC 3.0.0-git; 2.2.x vs 3.0.0 settings are
not fully interchangeable; 3.0.0-git version, even when run from an
unzipped package (like Richard did) will still write on %APPDATA%\
and overwrite 2.2.x's settings.
As I'm on a 32bit OS, I have always used the win32.7z packages
of nightly and never had any issues opening the "Media ->
Open Network Stream" popup and pasting a URL there...

ogg recording playback issues:

 As Jim has said, the whole technique of streaming FLAC
encoded audio data via MPEG-DASH (FLAC encapsulation
inside the MP4 container and creation of a segmented mp4 stream)
is still quite experimental; as such, recording of that stream by VLC
is even more so...
Playback of the recorded .ogg file is supported by VLC 3 itself,
BUT NOT by previous VLC versions.
A few other software players also do, like latest PotPlayer
(released and beta versions) and the released (1.7.13) and
beta (1.7.13.60) versions of MPC-HC (which uses the FFmpeg
based LAV Filters); MPC-BE will start to play the file, but will
crash towards the end of the recording.

.ogg recording extracting issues:

 I had already mentioned these towards the end of previous post:
http://lists.infradead.org/pipermail/get_iplayer/2017-August/010957.html
Please understand that the RAW flac stream inside the OGG
container is the product of concatenation of successive DASH segments,
so not really a proper flac stream; the whole situation is similar to iso6 
mp4
files created by dash stream dumping; these are not standard mp4 files,
and in the case of GiP ffmpeg is needed to remux them properly
into a standard MP4 variant palatable to most (soft|hard)ware MP4 players.
Perhaps in the not so far future, ffmpeg will be patched to
losslessly extract this dash-flac ES from a container, for the
moment though it's necessary to losslessly recode to flac
to make this possible (and reduce FFmpeg verbosity to -v 8
to remove all the DTS warnings...).
BTW, my command

ffmpeg -v 8 -stats -i "vlc-record-2017-08-03-01h36m18s-Radio 3
lossless-.ogg" -vn -c:a flac "Radio 3 lossless.flac"

is in essence identical to RS's

ffmpeg -i=<infile>.ogg -f=flac -sample_fmt=s16 <outfile>.flac

as "-f flac -sample_fmt=s16" forces ffmpeg to use the flac encoder

@all:
For the nth time, the BBC DO NOT PROVIDE R3 AOD
as lossless flac encodes, certainly not in their browser embedded
DASH player (Flash is unsuitable for the task); hence no FLAC
is retrievable via GiP! It is pure speculation (at best, very premature... )
to discuss now what will happen in the future...

Audacity has come up in the past in this list (I think't was CJB
who suggested it for audio recordings on-the-fly).
Audacity and many other so-called audio recorders
(I occasionally use mp3DirectCut) are acting as man-in-the-middle
and making use of the so-called "analog loop(hole)"
https://en.wikipedia.org/wiki/Analog_hole
as detailed by Richard in
http://lists.infradead.org/pipermail/get_iplayer/2017-August/010979.html
VLC-3.0.0 (and patched FFmpeg) will produce
digital clones of the flac stream.

@Paul Thornett
 You are, of course, entitled to your own opinion,
but I can't find personally any justification for your overall
aversion to VLC; I think it's a hugely versatile Audio-Video
open-source application, that has saved the day for me
on countless occasions...
 And please, can you refrain from discussing BBC
geo-blocking circumvention methods in this list?
The list maintainer has explicitly stated in the past
that such topics are not tolerated here...
(And as you've discovered yourself, the beeb are
on a constant battle blacklisting many of these methods...).
FWIW, the test R3 live flac stream is not geo-filtered,
can be accessed DIRECT...
Enjoy it while you (and I) can, because if it ever makes it
into a standard R3 feature, it'll be UK-only (as I suspect
the beeb can't afford the huge bandwidth costs of
serving a 550kbps stream globally!).

@jim web
The longest recording of the R3 live flac stream I ever
did with my patched FFmpeg was 4 hour long; I did
not witness any gaps; judging from past GiP experience,
loss of segments of an HLS/DASH stream may happen
when latency is introduced or some technical fault at the
server side (e.g. overload); so many factors come into play
that it's impossible to control everything on the client side;
when your ffmpeg errors out, what is the exact nature of the
error and does it resume recording afterwards?
(it's doubtful it matters, but the crypto lib on my compile is the
non-free libressl, openssl fork; have you used GnuTLS yourself?)

 I used to use ffmpeg in the past for live stream recordings,
but when, for whatever reason, there were streaming outages,
the recording would end abruptly; VLC auto picks-up the
recording when the streaming resumes, so I've switched to VLC...

> because flac becomes standard
> and gip can then fetch it. :-)

The definition of "wishful thinking" there, Jim? :-)

Best regards,
Vangelis.