Abstract: A facility for completing a set of operations is described. Under the control of an application, the facility registers the background task to perform the set of operations. In response to the registration of the background task, the facility repeatedly invokes the background task to perform the set of operations.

Abstract: An off-host audio engine interface exposes audio processing capabilities to a host. The interface receives offloaded audio streams and a host-processed audio stream from the host. The off-host audio engine processes the offloaded audio streams individually to create off-host-processed audio streams. The host-processed audio stream is mixed with the off-host-processed streams to create a mixed stream. The mixed stream undergoes audio processing by the off-host engine. The off-host audio engine provides output and reference audio streams based on the mixed audio stream. The reference stream can be provided to the host via the interface. Via the interface, the host can control local and global audio processing performed by the off-host engine by enabling or disabling local and global processing, and by enabling or disabling local and global audio processing components of the off-host audio engine.

Abstract: An off-host audio engine interface exposes audio processing capabilities to a host. The interface receives offloaded audio streams and a host-processed audio stream from the host. The off-host audio engine processes the offloaded audio streams individually to create off-host-processed audio streams. The host-processed audio stream is mixed with the off-host-processed streams to create a mixed stream. The mixed stream undergoes audio processing by the off-host engine. The off-host audio engine provides output and reference audio streams based on the mixed audio stream. The reference stream can be provided to the host via the interface. Via the interface, the host can control local and global audio processing performed by the off-host engine by enabling or disabling local and global processing, and by enabling or disabling local and global audio processing components of the off-host audio engine.

Abstract: The driving of an audio device that supports two or more audio modes is accomplished by associating a first physical device object of an audio device with a first device identifier, the first physical device object representing a first audio mode enumerated by a bus enumerator; associating a second physical device object of an audio device with a second device identifier, the second physical device object representing a second audio mode enumerated by the bus enumerator; and if the first device identifier matches the second device identifier, enabling a coupled kernel streaming audio interface compatible with both the first physical device object and the second physical device object.

Abstract: Systems and methods for parsing flexible audio codec topologies are described. In one aspect, codec topology information is obtained from an audio codec. The codec topology information includes a list of processing node connections and configuration default data for respective processing nodes associated with the audio codec. The codec topology information is evaluated to identify valid audio codec topologies based on set of valid connection path criteria.

Abstract: The driving of an audio device that supports two or more audio modes is accomplished by associating a first physical device object of an audio device with a first device identifier, the first physical device object representing a first audio mode enumerated by a bus enumerator; associating a second physical device object of an audio device with a second device identifier, the second physical device object representing a second audio mode enumerated by the bus enumerator; and if the first device identifier matches the second device identifier, enabling a coupled kernel streaming audio interface compatible with both the first physical device object and the second physical device object.

Abstract: Systems and methods for parsing flexible audio codec topologies are described. In one aspect, codec topology information is obtained from an audio codec. The codec topology information includes a list of processing node connections and configuration default data for respective processing nodes associated with the audio codec. The codec topology information is evaluated to identify valid audio codec topologies based on set of valid connection path criteria.

Abstract: An audio signal processing device has input and output devices, a processor, an accelerator device in communication with the foregoing, and a memory for a storing a driver containing multiple filters of an audio filter graph. The driver controls the accelerator device. The filters contained within the driver can be executed by the accelerator device. Each filter transforms and outputs audio data in a predetermined manner. One filter mixes audio data received by the input device and another renders the mixed audio data for output by the output device. Global effect filters and acoustic cancellation filters can follow the mixing filter to, respectively, achieve a global effect on all input audio data and to cancel echoes therefrom.