Hi, Eugene.Actually, I think you want to support WAVE_FORMAT_EXTENSIBLE in your driver. It's a more recent format descriptor than WAVE_FORMAT_PCM that provides a way to specify bit depth and channel location. I believe it is required when using more than two channels of audio and/or audio samples with a depth of more than 16 bits.
You can find more information at: http://www.microsoft.com/whdc/device/audio/multichaud.mspx http://msdn.microsoft.com/library/en-us/Audio_d/hh/Audio_d/aud-design_35c3556b-05e1-4a90-97a3-e9945d400ee1.xml.asp Hope that helps! -Dan ----- Original Message -----
Date: Wed, 13 Dec 2006 11:55:49 +0600 From: Eugene Muzychenko <emuzychenko@xxxxxxxxx> Subject: [wdmaudiodev] Distinguish between basic and extensible formats Hello! Does anybody know how to correctly distinguish between basic and extensible audio formats in the driver? Working under Windows 2000 and XP, my driver periodically get the KSDATAFORMAT descriptor with KSDATAFORMAT_SPECIFIER_WAVEFORMATEX specifier from the sysaudio driver. Checking the WaveFormatEx descriptor, the driver finds WAVE_FORMAT_EXTENSIBLE in wFormatTag field and a zero in the cbSize field. Must the driver reject such format descriptor as invalid or simply ignore the WAVE_FORMAT_EXTENSIBLE, assuming there is WAVE_FORMAT_PCM? SubFormat parameter in the KSDATAFORMAT descriptor is KSDATAFORMAT_SUBTYPE_PCM. Regards, Eugene
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