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can we change the block size?

From: Robert O'Callahan <robert@ocallahan.org>
Date: Tue, 1 Jan 2013 00:11:45 +1300
Message-ID: <CAOp6jLYhECQEDPuJWwHFyTxRRMJ07syofoCLq5M9PHTd8xg4ew@mail.gmail.com>
To: public-audio@w3.org
The spec requires block processing with 128 sample-frames per block. This
can be a bit inconvenient when interfacing with other code. For example,
the code at http://www.webrtc.org/ wants to capture, send and receive audio
in chunks of exactly 10ms. So when using Web Audio with that WebRTC code,
it would be nice to have 10ms be a whole number of Web Audio blocks.
Unfortunately that means choosing a sample rate which is a multiple of
128*100, which common sample rates aren't.

If the standard block size was 32 samples instead, then for common sample
rates such as 16KHz, 32KHz and 48KHz 10ms would be an exact number of Web
Audio blocks. Is there any reason why we can't or shouldn't do that?

BTW what are the actual constraints on the block size in the spec? Does it
only affect the sampling of k-rate parameters?

Thanks,
Rob
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Received on Monday, 31 December 2012 11:12:13 UTC

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