b47db27181
Return error if opened in mono mode cuz not supported.
Add support for Pa_GetCPULoad();
Fixed timestamp in callback and Pa_StreamTime() (Thanks n++k for the advice!)
Check for invalid sample rates and return an error.
Check for getenv("PA_MIN_LATEWNCY_MSEC") to set latency externally.
Better error checking for invalid channel counts and invalid devices.
34 lines
1.1 KiB
Text
34 lines
1.1 KiB
Text
Notes on Core Audio Implementation of PortAudio
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by Phil Burk and Darren Gibbs
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Document last updated March 20, 2002
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WHAT WORKS
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Output with very low latency, <10 msec.
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Half duplex input or output.
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Full duplex on the same CoreAudio device.
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The paFLoat32, paInt16, paInt8, paUInt8 sample formats.
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Pa_GetCPULoad()
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Pa_StreamTime()
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KNOWN BUGS OR LIMITATIONS
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We do not yet support simultaneous input and output on different
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devices. Note that some CoreAudio devices like the Roland UH30 look
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like one device but are actually two different CoreAudio devices. The
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BuiltIn audio is typically one CoreAudio device.
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Mono doesn't work.
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DEVICE MAPPING
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CoreAudio devices can support both input and output. But the sample
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rates supported may be different. So we have map one or two PortAudio
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device to each CoreAudio device depending on whether it supports
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input, output or both.
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When we query devices, we first get a list of CoreAudio devices. Then
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we scan the list and add a PortAudio device for each CoreAudio device
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that supports input. Then we make a scan for output devices.
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