[clug] Broadcast wav format

[Paul Wayper]

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Mike Carden wrote:
> On 3/23/07, Ian Matters <ian at matters.id.au> wrote:
>> There's an article on BWF in Wikipedia.  Maybe this will help.
>>
>> See: http://en.wikipedia.org/wiki/Broadcast_wave_format
> 
> Thanks Ian. I'm familiar with that and with the EBU links to the
> 'standard' at the end of the wiki article. I reckon by now I'm also
> well acquainted with every web page on the net that has any indexable
> content on the format and on its close friend WAV. :-)
> 
> BWF extends WAV in ways intended to make it suitable for professional
> and archival use, but it appears that it's a case of building a vault
> on quicksand. WAV is proprietary, poorly documented (to my surprise)
> and rarely implemented twice the same way. BWF has lofty goals, but
> almost nobody has implemented them. Those that have done so[1],
> appear to have mucked it up, and even if it's done right it relies on
> WAV being done properly everywhere. Which it isn't.

WAV is actually a variant of RIFF, which is another lofty 'interchange
standard' that failed because what was being transferred was never
consistently specified.  Half the problem with WAV, I reckon, is that half the
WAV writer software out there probably glommed the headers together using
guesswork, chewing gum and yoghurt and eschewed anything as helpful as a
specification document.

> So when someone well-meaning creates some 'archival quality' stereo
> audio at 96000 samples per second and 24 bits per sample linear pulse
> code modulation, it turns out that the resulting file is only useful
> if players ignore important formatting bits of the headers. So anyone
> trying to move such a file to a more sustainable format like, for
> instance, FLAC, will find themselves with a nigh unplayable but
> perfectly valid FLAC file.

One thought is to make a fairly simple filter that 'corrects' the WAV info and
feed that into FLAC through stdin.  Or simply strip off the bad headers and
send it straight in as raw PCM.

I assume the source recordings are not available?

HTH,

Paul
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