ViewCast Osprey PCI, User Manual

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Osprey PCI User Guide
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Figure 63. AudioConfig
The choices are to allow Any Supported Rate, or to force the sampling rate to be 32 kHz, 44.1 kHz, or
48 kHz. If Any Supported Rate is selected, all three rates, 32, 44.1, and 48 kHz, are available for
selection by the Microsoft Kmixer driver. Kmixer, however, does not necessarily select the optimum
hardware rate for a given software rate. It may specify a 44.1 kHz hardware rate when supplying 16
kHz software rate to the application, for example. In this case it would be better to set the Preferred
Audio Sample Rate 32 kHz, so that downsampling is exactly 2:1.
When the audio input is SDI, the only sample rate that the Osprey hardware supports is 48 kHz. The
driver will override your setting here.
When the audio input is DV1394, you have to use this control to match your audio sample rate to
the actual rate of the incoming data. The two most common formats are 48 kHz/16-bit, and 32
kHz/12-bit. You may have to listen to a captured sample of your audio to determine whether the
sample rate is set correctly – if the pitch is incorrect, try the other setting.
Mono Source Mode
If set to Use Left Channel, then left channel audio data is copied to the right channel.
If set to Use Right Channel, then right channel audio data is copied to the left channel.
If set to Average Left and Right, no copying is done.
The Microsoft Kmixer component always averages both channels when converting to mono. If a
signal is present on, say, the left channel only, the Average mode will average the left channel with