[Flac] 1.43 GB FLAC with 8-Hour Audio Inside... Decoding?

[Brian Willoughby]

You're running into the limits of other audio file formats.

AIFF and WAV both have limits.  Those two file formats absolutely  
cannot go beyond 4 GB because there are only 32-bit values for the  
lengths and sizes.  In addition, due to the fact that many operating  
systems default to signed numbers for 32-bit values, the more typical  
limitation is 2 GB, since negative sizes are meaningless.  There are  
operating system API which can handle the full unsigned 32-bit size  
and go all the way to 4 GB, but those are rare, and not many programs  
are written to use them.  For maximum compatibility, many programs  
refuse to go beyond 2 GB even thought they might be able to squeeze 4  
GB into a file.

What this all means is that stereo 16-bit 48 kHz audio has a maximum  
time limit of just over 3 hours (6 hours if you're lucky) when using  
AIFF or WAV.

There are a few solutions.

1) You could find a native FLAC player, and just listen to the 8-hour  
FLAC without converting.

2) You could use the --skip= and --until= parameters of the command- 
line flac to extract 3-hour segments that you can piece together  
later to make the full 8-hour piece.  You could use something like  
Logic to concatenate the AIFF (or WAV) files.  In other words, you'd  
have multiple files, each with a different part.  I'm not quite sure  
exactly what parameters you'd need to use to make sure that the first  
sample of the second file is immediately after the last sample of the  
first file, etc.  But I do know that Logic will piece together  
multiple files like this without a glitch.

3) You could wait for someone to write a direct FLAC to CAF  
extraction utility, because CAF does not have the 4 GB or 2 GB limit,  
and thus a single CAF file could hold the entire uncompressed 8-hour  
24/48 stereo audio.  Obviously, this isn't the most practical option  
for you now, but I point it out because it would be a great tool to  
have for exactly your situation.

P.S.  I feel your pain, because I have a portable recorder which  
streams directly to FLAC, and I have sometimes made recordings that  
are too long to fit into AIFF or WAV!  I had to learn these tricks in  
order to master the recordings into other formats, since listening to  
the raw FLAC is not optimal if you want processed audio.

Brian Willoughby
Sound Consulting


On Oct 5, 2009, at 22:25, Nathan Hevenstone wrote:
> Audacity results:
>
> It actually did save the file correctly, and the extracted WAV  
> itself is 5.14 GBs!  Problem is, Windows Media Player says the  
> track is only 1 hour and 47 minutes long, which is incorrect (as I  
> said before, it's an 8-hour track, meant for 8-hours of sleep)...
>
> So I played it in Quicktime, iTunes, and Nero Player just to be  
> sure.  Both QuickTime and iTunes only played 1 hour and 47  
> minutes.  Nero, on the other hand, only showed 1 hour and 47  
> minutes, but when it got to the end of that, it kept playing.
>
> I am so confused, and I really need help.  How do I decode this  
> extra-large FLAC file correctly so I can burn this series to a  
> DVD-9 and be done with it?
>
> On Tue, Oct 6, 2009 at 00:50, Nathan Hevenstone  
> <jimmyrrpage at gmail.com> wrote:
>> Ok, so here's the deal...
>>
>> I've been having a lot of trouble sleeping, so I've done some  
>> research and discovered this program called "Hemi-Sync".  I  
>> decided to torrent it from the Pirate Bay to try it out before  
>> spending my money.  What I torrented worked incredibly, so bought  
>> it, then torrented another Hemi-Sync program: Lucid Dreaming.   
>> It's a DVD-Audio program.
>>
>> What I torrented came with 4 tracks.  The first three tracks are  
>> 90 minutes each.  The 4th track is 8 hours long.  It is this 4th  
>> track I'm having trouble with.
>>
>> The first 3 files decoded from FLAC to 48 kHZ 16 bits Stereo (1536  
>> kbps) WAV without a problem.  The 4th one, however, simply will  
>> not decode.  I have used both Trader's Little Helper and FLAC  
>> Frontend.  I have torrented NCH Switch Sound File Converter, and  
>> nothing happened there (it decoded the file, but in two second,  
>> and the 1.43 GB FLAC file became a 2.76 KB WAV file).  I'm trying  
>> Audacity now, but I have mostly doubts... and I'll let y'all know  
>> if it works.