[Flac-dev] 96k/24-bit BWF encoding

[Justin Waddell]

I converted the file to AIFF and then encoded with flac (with no
warnings this time) and the same problem occurred. So it looks like
the problem could be with the 96k/24 bit implementation of flac in
various media players - foobar2000 is the only one found so far to
play the file correctly from about 8 players on both windows and
linux.

We originally thought the problem might have been with the software
producing the file as we only had files produced by an old version of
cube-tec's Quadriga software. However we have a second source of BWFs
now, and the same problem occurs.

On 5/7/07, Brian Willoughby <brianw at sounds.wa.com> wrote:
> Hi Justin,
>
> I have a suggestion, but it may not be very convenient.  You could
> try converting the 24/96 BWF to AIFF, and then use flac to compress
> the 24/96 AIFF.  There is no difference in audio quality between the
> FLAC file generated from BWF (WAV) vs. AIFF, so perhaps this extra
> step will solve your problem in the short term.  Sorry I haven't used
> BWF or WAV very frequently, but 24/96 AIFF compresses fine, and I
> have verified this on many occasions.
>
> What software are you using to create the BWF?  There was a case on
> the Flac mailing list recently where the WAV file was incorrectly
> formatted, and the same warning appeared.  If that is the case, using
> software which correctly implements the WAV format will give better
> results.
>
> Brian W.
>
>
> On May 6, 2007, at 17:37, Justin Waddell wrote:
>
> I am attempting to use flac to encode 96k/24-bit broadcast wav (BWF)
> files. BWFs are wav files with some extra meta-data chunks, and is the
> favoured archival format for many institutions around the world.
>
> These files are encoded successfully by flac, however the resulting
> flac file is not playable on all flac players - it plays successfully
> in foobar2000 but is silent in winamp, and when using the illuminable
> plugin for windows media player it informs me that a codec to play the
> file could not be found. Other flac files play successfully in winamp
> and windows media player.
>
> The flac encoder does give a warning during the encoding process:
>
> WARNING: legacy WAVE file has format type 1 but bits-per-sample=24
>
> Looking at the specs for WAV files, it appears that for 24-bit files
> should have their format code set to WAVE_FORMAT_EXTENSIBLE, but these
> files are still set to WAVE_FORMAT_PCM. Could this be the source of
> the problem? If not, do you have any other ideas?
>
> I can provide example files if wanted.
>
> Thanks,
>
> Justin
>
>