Let's develop an open-source media archive standard

From: der Mouse <mouse_at_Rodents.Montreal.QC.CA>
Date: Wed Aug 11 17:21:41 2004

> What shall we do with analog audio? Sample at 44.1KHz / 16-bit PCM
> and call it done?

No! Please! Not for archival purposes! 44.1KHz is good enough for
casual listening, for most people, but it is not good enough for
archival - and for a serious audiophile, it's not enough even for
listening.

If I had analog audio to digitize for archival purposes, I'd aim for
1MHz sample rate and at least 24bit (preferably 32bit) A->D. It seems
like overkill by today's standards, but storing a couple of orders of
magnitude more data is cheap compared to discovering you need - or even
just want - data that simply isn't there now that the original's gone.

Of course, this is a choice to be made by the person converting the
analog data to digital. I think the format spec should be able to
describe whatever that person chooses; I think it would be a _very_ bad
idea to assume anything about what that choice will be. The format
should be able to handle anything from 3 bits/sample compressed sound
such as I get from my voice modem, or even less, to multi-MHz sample
rates at hundreds of bits per sample (8-eg, channel 32bpp = 256 bits
per sampling tick). For audio, you probably could get away with
capping it at a few GHz sample rate - I'm not sure air can carry
frequences that high - but I see no reason to impose any limit.

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Received on Wed Aug 11 2004 - 17:21:41 BST