IAudioCaptureClient Interface

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IAudioCaptureClient Interface

The IAudioCaptureClient interface enables a client to read input data from a capture endpoint buffer. The client obtains a reference to the IAudioCaptureClient interface on a stream object by calling the IAudioClient::GetService method with parameter riid set to REFIID IID_IAudioCaptureClient.

The methods in this interface manage the movement of data packets that contain capture data. The length of a data packet is expressed as the number of audio frames in the packet. The size of an audio frame is specified by the nBlockAlign member of the WAVEFORMATEX (or WAVEFORMATEXTENSIBLE) structure that the client obtains by calling the IAudioClient::GetMixFormat method. The size in bytes of an audio frame equals the number of channels in the stream multiplied by the sample size per channel. For example, the frame size is four bytes for a stereo (2-channel) stream with 16-bit samples. A packet always contains an integral number of audio frames.

When releasing an IAudioCaptureClient interface instance, the client must call the Release method of the instance from the same thread as the call to IAudioClient::GetService that created the object.

For a code example that uses the IAudioCaptureClient interface, see Capturing a Stream.

IAudioCaptureClient inherits from the IUnknown interface. In addition to the methods inherited from IUnknown, IAudioCaptureClient supports the following methods.

Method Description
GetBuffer Retrieves a pointer to the next available packet of data in the capture endpoint buffer.
GetNextPacketSize Retrieves the number of frames in the next data packet in the capture endpoint buffer.
ReleaseBuffer Releases the buffer.


Client: Windows Vista

Header: Include Audioclient.h.

See Also

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