Re: Monitoring Level While Capturing



On Mon, 3 Jul 2006 15:34:01 -0700, James wrote:

Thanks for the response. When you refer to a number of capture buffers, do
you mean copy the small buffer that's actually doing the capture to a series
of private buffers that total at least two seconds of capture time before
writing to disk?

No, I'm referring to the actual capture buffers. As Windows can get busy
with things from time to time you need several capture buffers in queue for
the driver to write to in the event that your app can't respond for a
while. This doesn't affect latency as under normal circumstances you as
still receiving the buffers as soon as they are completed, but if things
get backlogged you will get a number of buffers quickly delivered when
things get caught up. In mission critical recording I use up to 10 seconds
worth of capture buffers (around 100 buffers).

And yes, it pays to buffer before writing to disk as well if you have the
disk writing in a separate thread. This technique is sometimes called
double-buffering.

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