Struct MTAudioProcessingTap

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pub struct MTAudioProcessingTap { /* private fields */ }

Available on crate feature MTAudioProcessingTap only.

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Apple’s documentation

Implementations§

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impl MTAudioProcessingTap

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pub unsafe fn create( allocator: Option<&CFAllocator>, callbacks: NonNull<MTAudioProcessingTapCallbacks>, flags: MTAudioProcessingTapCreationFlags, tap_out: NonNull<*const MTAudioProcessingTap>, ) -> i32

Available on crate features objc2-core-audio-types and objc2-core-media only.

Create a new processing tap.

This function creates a processing tap. The processing tap will then be used to process decoded data. The processing is performed on audio either before or after any effects or other processing (varispeed, etc) is applied by the audio queue.

Parameter allocator: The allocator to use to allocate memory for the new tap. Pass NULL or kCFAllocatorDefault to use the current default allocator.

Parameter callbacks: Callbacks struct. MTAudioProcessingTap will make a copy of this struct.

Parameter flags: Flags that are used to control aspects of the processing tap. Valid flags are:

kMTAudioProcessingTapCreationFlag_PreEffects: processing is done before any further effects are applied by the audio queue to the audio.
kMTAudioProcessingTapCreationFlag_PostEffects: processing is done after all processing is done, including that of other taps.

Parameter tapOut: The processing tap object.

Returns: An OSStatus result code.

§Safety

callbacks must be a valid pointer.
tap_out must be a valid pointer.

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pub unsafe fn storage(&self) -> NonNull<c_void>

Used by a processing tap to retrieve a custom storage pointer.

Parameter tap: The processing tap.

Returns: The tapStorage returned by the init callback.

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pub unsafe fn source_audio( &self, number_frames: CMItemCount, buffer_list_in_out: NonNull<AudioBufferList>, flags_out: mut MTAudioProcessingTapFlags, time_range_out: mut CMTimeRange, number_frames_out: *mut CMItemCount, ) -> i32

Available on crate features objc2-core-audio-types and objc2-core-media only.

Used by a processing tap to retrieve source audio.

This function may only be called from the processing tap’s callback.

Parameter tap: The processing tap.

Parameter numberFrames: The number of frames the processing tap requires for its processing.

Parameter bufferListInOut: The audio buffer list which will contain the source data. On input, all fields except for the buffer pointers must be filled in. If the buffer pointers are NULL (recommended), non-NULL pointers will be returned and system owns the source buffers; these buffers are only applicable for the duration of the processing tap callback. If the buffer pointers are non-NULL, then they must be big enough to hold numberFrames, and the source data will be copied into these buffers.

Parameter flagsOut: Flags to describe state about the input requested, e.g., discontinuity/complete. Can be NULL.

Parameter timeRangeOut: The asset time range corresponding to the provided source audio frames. Can be NULL.

Parameter numberFramesOut: The number of source frames that have been provided. Can be NULL. This can be less than the number of requested frames specified in numberFrames.

Returns: An OSStatus result code.

§Safety

buffer_list_in_out must be a valid pointer.
flags_out must be a valid pointer or null.
time_range_out must be a valid pointer or null.
number_frames_out must be a valid pointer or null.

Methods from Deref<Target = CFType>§

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pub fn downcast_ref<T>(&self) -> Option<&T>
where T: ConcreteType,

Attempt to downcast the type to that of type T.

This is the reference-variant. Use CFRetained::downcast if you want to convert a retained type. See also ConcreteType for more details on which types support being converted to.

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pub fn retain_count(&self) -> usize

Get the reference count of the object.

This function may be useful for debugging. You normally do not use this function otherwise.

Beware that some things (like CFNumbers, small CFStrings etc.) may not have a normal retain count for optimization purposes, and can return usize::MAX in that case.