blob: 0abdd3db04c32071e3117af578058329373b0271 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
|
Notes on Core Audio Implementation of PortAudio
by Phil Burk and Darren Gibbs
Document last updated October 18, 2002
WHAT WORKS
Output with very low latency, <10 msec.
Half duplex input or output.
Full duplex
The paFLoat32, paInt16, paInt8, paUInt8 sample formats.
Pa_GetCPULoad()
Pa_StreamTime()
KNOWN BUGS OR LIMITATIONS
The iMic supports multiple sample rates.
But there is a bug when changing sample rates:
Run patest_record.c at rate A - it works.
Then run patest_record.c at rate B - it FAIL!
Then run patest_record.c again at rate B - it works!
DEVICE MAPPING
CoreAudio devices can support both input and output. But the sample
rates supported may be different. So we have map one or two PortAudio
device to each CoreAudio device depending on whether it supports
input, output or both.
When we query devices, we first get a list of CoreAudio devices. Then
we scan the list and add a PortAudio device for each CoreAudio device
that supports input. Then we make a scan for output devices.
(minor change to test CVS)
|
