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Josh Coalson
2005-03-31, 15:03
--- Vidur Apparao <vidur (AT) slimdevices (DOT) com> wrote:
> Steinar Bjaerum wrote:
>
> >..
> >
> >Please correct me if I am wrong, but:
> >
> >The Flac file consists of frames which are the smallest entity that
> can be
> >decoded independently. The Seekpoints in the SEEKTABLE metablocks
> are
> >located at frame boundaries. The start sample of a track is
> typically
> >located in the middle of a frame. In order to start playing a track
> at the
> >correct position, the entire frame containing the start sample of
> the track
> >needs to be decoded, and the samples in the frame prior to the track
> start
> >sample needs to be thrown away (these samples belong to the previous
> track).
> >Similarly, the frame containing the end sample of the track needs
> special
> >treatment.
> >
> >It is feasible to let Perl parse the SEEKTABLE and have the server
> start
> >streaming at the frame containing the start sample of the track.
> However,
> >the Flac decoder in the client needs to get additional information
> about the
> >samples that need to be thrown away after decoding the frames
> containing the
> >start and end samples of the track. This means that it is not just a
> Perl
> >parsing job that has to be done in order to avoid transcoding the
> cued
> >Flacs. However, I'm sure the guys at SlimDevices can do it!
> >
> >
>
> You are absolutely correct. If we did cuesheet-based seeking within
> the
> server, we'd have to start streaming to the SB2 from the start
> position
> of the frame *and* send the decoder the number of frames to drop at
> the
> start and end of the stream.
>
> Thanks for your vote of confidence. ;-)
> --Vidur

sorry I'm late to the party (I'm the guy who started FLAC),
just recently joined the lists. I missed most of the context
but is there something I can answer or maybe add to flac
that would facilitate cuesheet support? I'm still coming up
to speed on the code and workings of slimserver/squeezebox,
so I'm not sure how cuesheet-based seeking works, but another
possibility is to decode/chop/reencode any partial start/end
frame on the server side. (as long as there was a mechanism in
perl to do this.) that way the seeking protocol would not
have to be changed.

Josh




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Gordon Harris
2005-03-31, 21:41
Josh Coalson <xflac@...> writes:

> sorry I'm late to the party (I'm the guy who started FLAC),
> just recently joined the lists.

Welcome aboard, Josh!

Daryle A. Tilroe
2005-03-31, 22:05
Josh Coalson wrote:

> sorry I'm late to the party (I'm the guy who started FLAC),
> just recently joined the lists. I missed most of the context

WOW! I thought the name looked familiar. It's like having a
celebrity in our midst. You will find many of your followers
here; divided along track vs. CD lines; but still united in their
devotion to FLAC. ;-)

--
Daryle A. Tilroe

Jay Sissom
2005-04-01, 11:36
This is more of a general question about Flac encoding. Quite a few
people are using it, but I've found the tools that I've looked at are
just a little difficult to deal with. I used CDex and iTunes to rip
CD's to mp3's. Is there an open source tool like that for Flac? So
far, all the tools I've seen require multiple steps for ripping, CDDB
then flac conversion. I have Windows, Mac OS and Linux, but would
prefer a Windows or Mac OS tool because Linux is my server.

Thanks
Jay


On Apr 1, 2005 10:58 AM, Steinar Bjaerum <steinar.bjaerum (AT) online (DOT) no> wrote:
> > --- Vidur Apparao <vidur (AT) slimdevices (DOT) com> wrote:
> > > Steinar Bjaerum wrote:
> > >
> > > >..
> > > >
> > > >Please correct me if I am wrong, but:
> > > >
> > > >The Flac file consists of frames which are the smallest entity that
> > > can be
> > > >decoded independently. The Seekpoints in the SEEKTABLE metablocks
> > > are
> > > >located at frame boundaries. The start sample of a track is
> > > typically
> > > >located in the middle of a frame. In order to start playing a track
> > > at the
> > > >correct position, the entire frame containing the start sample of
> > > the track
> > > >needs to be decoded, and the samples in the frame prior to the track
> > > start
> > > >sample needs to be thrown away (these samples belong to the previous
> > > track).
> > > >Similarly, the frame containing the end sample of the track needs
> > > special
> > > >treatment.
> > > >
> > > >It is feasible to let Perl parse the SEEKTABLE and have the server
> > > start
> > > >streaming at the frame containing the start sample of the track.
> > > However,
> > > >the Flac decoder in the client needs to get additional information
> > > about the
> > > >samples that need to be thrown away after decoding the frames
> > > containing the
> > > >start and end samples of the track. This means that it is not just a
> > > Perl
> > > >parsing job that has to be done in order to avoid transcoding the
> > > cued
> > > >Flacs. However, I'm sure the guys at SlimDevices can do it!
> > > >
> > > >
> > >
> > > You are absolutely correct. If we did cuesheet-based seeking within
> > > the
> > > server, we'd have to start streaming to the SB2 from the start
> > > position
> > > of the frame *and* send the decoder the number of frames to drop at
> > > the
> > > start and end of the stream.
> > >
> > > Thanks for your vote of confidence. ;-)
> > > --Vidur
> >
> > sorry I'm late to the party (I'm the guy who started FLAC),
> > just recently joined the lists. I missed most of the context
> > but is there something I can answer or maybe add to flac
> > that would facilitate cuesheet support? I'm still coming up
> > to speed on the code and workings of slimserver/squeezebox,
> > so I'm not sure how cuesheet-based seeking works, but another
> > possibility is to decode/chop/reencode any partial start/end
> > frame on the server side. (as long as there was a mechanism in
> > perl to do this.) that way the seeking protocol would not
> > have to be changed.
> >
> > Josh
> >
>
> Josh,
>
> Great.
> Having the possibility of contributions from you, Sean will hopefully not
> pursue the idea of abandoning support for whole-album CUE-embedded FLACs,
> http://lists.slimdevices.com/archives/discuss/2005-March/046973.html
>
> To extract a single track from an album-FLAC without complete transcoding,
> you suggest to re-encode only the first and last frame of the track on the
> server before streaming to the client, and stream the other frames as is.
> This means that the first frame would be shorter than the other frames. How
> does that relate to the "FLAC subset" format described at
> http://flac.sourceforge.net/format.html#subset where it is stated that to be
> truly streamable the block size should be constant?
>
> I am not at all an expert on this, just an idea: Do you consider
> functionality for sample-accurate extraction of a track from a CUE-embedded
> FLAC to a separate standalone format compliant FLAC stream to be generic
> enough to be added to libFLAC? I know this can be easily done by using the
> index points to decode and then encode (as is currently done in SlimServer).
> I'm thinking about a more efficient method that could take advantage of the
> fact that both the input and output is FLAC.
>
> Steinar
>
>
>

Thomas B. Malsbury
2005-04-01, 11:53
When I re-ripped all my CDs to Flac, I used dbPowerAmp with the add-on
Flac Codec. It worked very well for me.

http://www.dbpoweramp.com/dmc.htm

The only problem that I have is that all my ripping, tagging and storage
was done in a Windows environment and my SlimServer runs on a linux
box. Since the upgrade to 6.0 some files with special characters were
not found since the language sets were not specified in my samba share.
This seems to be more a Linux-Windows problem in my setup and not a
problem with SlimServer 6.0. Just the changes in 6.0 manifested a
problem with my setup. Dan Sully is already aware and helped me track
down the problem. I just wanted to through that out there since you
mentioned you might be moving your files from one OS to another after
the ripping process.

Tom Malsbury




Jay Sissom wrote:

>This is more of a general question about Flac encoding. Quite a few
>people are using it, but I've found the tools that I've looked at are
>just a little difficult to deal with. I used CDex and iTunes to rip
>CD's to mp3's. Is there an open source tool like that for Flac? So
>far, all the tools I've seen require multiple steps for ripping, CDDB
>then flac conversion. I have Windows, Mac OS and Linux, but would
>prefer a Windows or Mac OS tool because Linux is my server.
>
>Thanks
>Jay
>
>

Mark Bennett
2005-04-01, 12:24
CDEx can be configured to encode to Flac - it's what I used to use
before I went Linux....

See the last post in:
http://www.hydrogenaudio.org/forums/lofiversion/index.php/t12909.html

for details.


On Fri, 2005-04-01 at 13:36 -0500, Jay Sissom wrote:
> This is more of a general question about Flac encoding. Quite a few
> people are using it, but I've found the tools that I've looked at are
> just a little difficult to deal with. I used CDex and iTunes to rip
> CD's to mp3's. Is there an open source tool like that for Flac? So
> far, all the tools I've seen require multiple steps for ripping, CDDB
> then flac conversion. I have Windows, Mac OS and Linux, but would
> prefer a Windows or Mac OS tool because Linux is my server.
>
> Thanks
> Jay
>

--
"The biggest problem encountered while trying to design a system that
was completely foolproof, was, that people tended to underestimate the
ingenuity of complete fools." (Douglas Adams)

Daryle A. Tilroe
2005-04-01, 21:32
Jay Sissom wrote:

> This is more of a general question about Flac encoding. Quite a few
> people are using it, but I've found the tools that I've looked at are
> just a little difficult to deal with. I used CDex and iTunes to rip
> CD's to mp3's. Is there an open source tool like that for Flac? So
> far, all the tools I've seen require multiple steps for ripping, CDDB
> then flac conversion. I have Windows, Mac OS and Linux, but would
> prefer a Windows or Mac OS tool because Linux is my server.

I really think this should be in the Wiki or FAQ or something. Someone
seems to ask once a month without checking the archives. So yet again
with EAC here are some links:

http://www.saunalahti.fi/cse/EAC/
http://home-12.tiscali-business.nl/~tpm54044/eac/eac2.htm

Really quite painless. EAC does all the ripping, CDDB tagging, and
FLAC encoding in one shot with queueing to boot.

--
Daryle A. Tilroe