C++/VB - Question about DirectSound notifications

Hey gang,
I've created a DirectSound test application with the capture notifier
set to 50 indexes (16000-2-byte samples (640 bytes) at 20 ms each).
So I would expect my callback thread to be called 50 times per second
with the buffersizes of 640 bytes.  I'm not seeing this.  What I am
seeing is (using MM timestamps as a test) is about 36 to 38 events per
second with some "woken-up" event durations at 0 ms and others with 50
ms.  What can I do to configure Directsound capture notifier to wake
up my thread every 20 ms with the correct buffer sizes?  My thread is
using ::MsgWaitForMultipleObjects().
/Loren

  Chris P. replied...

For one don't use MsgWaitForMultipleObjects().  Use WaitForSingleObject()
or WaitForMultipleObjects().

The event notifications in DirectSound are somewhat broken.  It is
particularly bad if there are multiple DirectSound applications running as
you will receive the other applications events as well.

--
http://www.chrisnet.net/code.htm
[MS MVP for DirectShow / MediaFoundation]

  Loren Rogers replied...

()
s

Thanks Chris,
What I wound up doing and it seems to work is wake up every 100 ms
(3200 bytes in this case) and then break that buffer into 5 smaller
buffers (640 bytes).  I need the smaller sample sizes for encoding/
network packetization.

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